diff mbox series

[v11,2/2] i2c: aspeed: support ast2600 i2c new register mode driver

Message ID 20230430041712.3247998-3-ryan_chen@aspeedtech.com
State Superseded
Headers show
Series Add ASPEED AST2600 I2Cv2 controller driver | expand

Commit Message

Ryan Chen April 30, 2023, 4:17 a.m. UTC
Add i2c new register mode driver to support AST2600 i2c
new register mode. AST2600 i2c controller have legacy and
new register mode. The new register mode have global register
support 4 base clock for scl clock selection, and new clock
divider mode. The i2c new register mode have separate register
set to control i2c master and slave.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
---
 MAINTAINERS                      |    9 +
 drivers/i2c/busses/Kconfig       |   11 +
 drivers/i2c/busses/Makefile      |    1 +
 drivers/i2c/busses/i2c-ast2600.c | 1596 ++++++++++++++++++++++++++++++
 4 files changed, 1617 insertions(+)
 create mode 100644 drivers/i2c/busses/i2c-ast2600.c

Comments

Andy Shevchenko May 2, 2023, 8:32 p.m. UTC | #1
On Sun, Apr 30, 2023 at 12:17:12PM +0800, Ryan Chen wrote:
> Add i2c new register mode driver to support AST2600 i2c
> new register mode. AST2600 i2c controller have legacy and
> new register mode. The new register mode have global register
> support 4 base clock for scl clock selection, and new clock
> divider mode. The i2c new register mode have separate register
> set to control i2c master and slave.

...

> +#include <linux/clk.h>
> +#include <linux/err.h>
> +#include <linux/i2c.h>
> +#include <linux/io.h>
> +#include <linux/slab.h>
> +#include <linux/delay.h>
> +#include <linux/reset.h>
> +#include <linux/module.h>
> +#include <linux/interrupt.h>
> +#include <linux/completion.h>
> +#include <linux/of.h>
> +#include <linux/of_irq.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/regmap.h>
> +#include <linux/of_device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/i2c-smbus.h>

Ordered?

...

> +#define AST2600_GLOBAL_INIT				\
> +			(AST2600_I2CG_CTRL_NEW_REG |	\
> +			AST2600_I2CG_CTRL_NEW_CLK_DIV)

Make just a one TAB and put the last two lines on the single one.

...

> +#define I2CCG_DIV_CTRL 0xC6411208

Is it decimal? Is it combination of bitfields? Can you add a comment what is
this magic?

...

> +struct ast2600_i2c_timing_table {
> +	u32 divisor;
> +	u32 timing;
> +};

Is it even used?

...

> +enum xfer_mode {
> +	BYTE_MODE = 0,

Why explicit assignment?

> +	BUFF_MODE,
> +	DMA_MODE,
> +};

...

> +	base_clk1 = (i2c_bus->apb_clk * 10) / ((((clk_div_reg & 0xff) + 2) * 10) / 2);
> +	base_clk2 = (i2c_bus->apb_clk * 10) /
> +			(((((clk_div_reg >> 8) & 0xff) + 2) * 10) / 2);
> +	base_clk3 = (i2c_bus->apb_clk * 10) /
> +			(((((clk_div_reg >> 16) & 0xff) + 2) * 10) / 2);
> +	base_clk4 = (i2c_bus->apb_clk * 10) /
> +			(((((clk_div_reg >> 24) & 0xff) + 2) * 10) / 2);

The same equation is used per each byte of clk_div_reg? Can it be rewritten to
avoid this and using loop, so you will have an array of base_clk to be filled?

Don't forget to use GENMASK().

...

> +	if ((i2c_bus->apb_clk / i2c_bus->bus_frequency) <= 32) {
> +		baseclk_idx = 0;
> +		divisor = DIV_ROUND_UP(i2c_bus->apb_clk, i2c_bus->bus_frequency);
> +	} else if ((base_clk1 / i2c_bus->bus_frequency) <= 32) {
> +		baseclk_idx = 1;
> +		divisor = DIV_ROUND_UP(base_clk1, i2c_bus->bus_frequency);
> +	} else if ((base_clk2 / i2c_bus->bus_frequency) <= 32) {
> +		baseclk_idx = 2;
> +		divisor = DIV_ROUND_UP(base_clk2, i2c_bus->bus_frequency);
> +	} else if ((base_clk3 / i2c_bus->bus_frequency) <= 32) {
> +		baseclk_idx = 3;
> +		divisor = DIV_ROUND_UP(base_clk3, i2c_bus->bus_frequency);

Will be optimized with above suggestion, I believe.

> +	} else {
> +		baseclk_idx = 4;
> +		divisor = DIV_ROUND_UP(base_clk4, i2c_bus->bus_frequency);
> +		inc = 0;
> +		while ((divisor + inc) > 32) {
> +			inc |= divisor & 0x1;
> +			divisor >>= 1;
> +			baseclk_idx++;
> +		}
> +		divisor += inc;

I think the above loop can be rewritten to have better representation.

> +	}

...

> +	baseclk_idx &= 0xf;

GENMASK()?

...

> +	scl_low = ((divisor * 9) / 16) - 1;
> +	scl_low = min_t(u32, scl_low, 0xf);

This can be done in one line. Also, why not 15?

...

> +	scl_high = (divisor - scl_low - 2) & 0xf;

GENMASK()?

...

> +	data = ((scl_high - 1) << 20) | (scl_high << 16) | (scl_low << 12) | (baseclk_idx);

Too many parentheses.

...

> +	/* due to master slave is common buffer, so need force the master stop not issue */
> +	if (readl(i2c_bus->reg_base + AST2600_I2CM_CMD_STS) & 0xffff) {

GENMASK() ?

> +		writel(0, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
> +		i2c_bus->cmd_err = -EBUSY;
> +		writel(0, i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> +		complete(&i2c_bus->cmd_complete);
> +	}

...

> +	/* send start */
> +	dev_dbg(i2c_bus->dev, "[%d] %sing %d byte%s %s 0x%02x\n",
> +		i2c_bus->msgs_index, msg->flags & I2C_M_RD ? "read" : "write",

str_read_write() ?

> +		msg->len, msg->len > 1 ? "s" : "",
> +		msg->flags & I2C_M_RD ? "from" : "to", msg->addr);

...

> +				for (i = 0; i < xfer_len; i++) {
> +					wbuf[i % 4] = msg->buf[i];
> +					if (i % 4 == 3)
> +						writel(*(u32 *)wbuf, i2c_bus->buf_base + i - 3);

Err.. There can be alignment issues.

> +				}
> +				if (--i % 4 != 3)
> +					writel(*(u32 *)wbuf, i2c_bus->buf_base + i - (i % 4));

The above code is ugly. Can you think about it and write in a better way?

...

> +				for (i = 0; i < xfer_len; i++) {
> +					wbuf[i % 4] = msg->buf[i2c_bus->master_xfer_cnt + i];
> +					if (i % 4 == 3)
> +						writel(*(u32 *)wbuf, i2c_bus->buf_base + i - 3);
> +				}
> +				if (--i % 4 != 3)
> +					writel(*(u32 *)wbuf, i2c_bus->buf_base + i - (i % 4));

Ditto.

...

Do you have similar code pieces? Why not doing it in a separate function with
parameters?

...

> +	return ast2600_i2c_master_irq(i2c_bus) ? IRQ_HANDLED : IRQ_NONE;

IRQ_RETVAL() ?

...

> +	writel(0xfffffff, i2c_bus->reg_base + AST2600_I2CM_ISR);

GENMASK()

...

> +	writel(0xfffffff, i2c_bus->reg_base + AST2600_I2CS_ISR);

Ditto.

> +	if (i2c_bus->mode == BYTE_MODE) {
> +		writel(0xffff, i2c_bus->reg_base + AST2600_I2CS_IER);

Ditto.

> +	} else {
> +		/* Set interrupt generation of I2C slave controller */
> +		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_IER);
> +	}

...

> +	WARN_ON(!i2c_bus->slave);

Why?

...

> +static const struct of_device_id ast2600_i2c_bus_of_table[] = {
> +	{
> +		.compatible = "aspeed,ast2600-i2cv2",
> +	},
> +	{}
> +};

> +

Redundant blank line.

> +MODULE_DEVICE_TABLE(of, ast2600_i2c_bus_of_table);

...

> +	i2c_bus = devm_kzalloc(dev, sizeof(*i2c_bus), GFP_KERNEL);
> +	if (!i2c_bus)
> +		return dev_err_probe(dev, -ENOMEM, "no memory allocated\n");

No. We do not print error message for ENOMEM.
You homework to find why.

...

> +	if (of_property_read_bool(pdev->dev.of_node, "aspeed,enable-dma"))

device_property_read_bool() ?

> +		i2c_bus->mode = DMA_MODE;

...

> +	if (i2c_bus->mode == BUFF_MODE) {
> +		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +		if (res && resource_size(res) >= 2) {
> +			i2c_bus->buf_base = devm_ioremap_resource(dev, res);
> +
> +			if (!IS_ERR_OR_NULL(i2c_bus->buf_base))
> +				i2c_bus->buf_size = resource_size(res) / 2;
> +		} else {
> +			i2c_bus->mode = BYTE_MODE;
> +		}
> +	}

Can be done without additional checks and with a simple call to
devm_platform_ioremap_resource(). No?

...

> +	/* i2c timeout counter: use base clk4 1Mhz,
> +	 * per unit: 1/(1000/4096) = 4096us
> +	 */

Wrong multi-line style of the comment.

...

> +	ret = of_property_read_u32(dev->of_node,
> +				   "i2c-scl-clk-low-timeout-us",
> +				   &i2c_bus->timeout);
> +	if (!ret)
> +		i2c_bus->timeout /= 4096;

What is this and why I2C core timings (standard) can't be utilized here?

...

> +	ret = of_property_read_u32(dev->of_node, "clock-frequency", &i2c_bus->bus_frequency);
> +	if (ret < 0) {
> +		dev_warn(dev, "Could not read clock-frequency property\n");
> +		i2c_bus->bus_frequency = 100000;
> +	}

There are macro for standard speeds. Moreover, there is a function to parse
properties, no need to open code.

...

> +	i2c_bus->adap.dev.of_node = dev->of_node;

device_set_node()

...

> +	if (of_property_read_bool(dev->of_node, "smbus-alert")) {

Doesn't core have already support for this?

> +		i2c_bus->alert_enable = true;
> +		i2c_bus->ara = i2c_new_smbus_alert_device(&i2c_bus->adap, &i2c_bus->alert_data);
> +		if (!i2c_bus->ara)
> +			dev_warn(dev, "Failed to register ARA client\n");
> +
> +		writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER | AST2600_I2CM_SMBUS_ALT,
> +		       i2c_bus->reg_base + AST2600_I2CM_IER);
> +	} else {
> +		i2c_bus->alert_enable = false;
> +		/* Set interrupt generation of I2C master controller */
> +		writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER,
> +		       i2c_bus->reg_base + AST2600_I2CM_IER);
> +	}

...

> +	dev_info(dev, "%s [%d]: adapter [%d khz] mode [%d]\n",
> +		 dev->of_node->name, i2c_bus->adap.nr, i2c_bus->bus_frequency / 1000,
> +		 i2c_bus->mode);

Useless noise.
Ryan Chen May 7, 2023, 2:21 a.m. UTC | #2
Hello Andy,
> 
> On Sun, Apr 30, 2023 at 12:17:12PM +0800, Ryan Chen wrote:
> > Add i2c new register mode driver to support AST2600 i2c new register
> > mode. AST2600 i2c controller have legacy and new register mode. The
> > new register mode have global register support 4 base clock for scl
> > clock selection, and new clock divider mode. The i2c new register mode
> > have separate register set to control i2c master and slave.
> 
> ...
> 
> > +#include <linux/clk.h>
> > +#include <linux/err.h>
> > +#include <linux/i2c.h>
> > +#include <linux/io.h>
> > +#include <linux/slab.h>
> > +#include <linux/delay.h>
> > +#include <linux/reset.h>
> > +#include <linux/module.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/completion.h>
> > +#include <linux/of.h>
> > +#include <linux/of_irq.h>
> > +#include <linux/mfd/syscon.h>
> > +#include <linux/regmap.h>
> > +#include <linux/of_device.h>
> > +#include <linux/dma-mapping.h>
> > +#include <linux/i2c-smbus.h>
> 
> Ordered?
Update by alphabetical order

#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/i2c-smbus.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/slab.h>
> ...
> 
> > +#define AST2600_GLOBAL_INIT				\
> > +			(AST2600_I2CG_CTRL_NEW_REG |	\
> > +			AST2600_I2CG_CTRL_NEW_CLK_DIV)
> 
> Make just a one TAB and put the last two lines on the single one.

Update by following. 

#define AST2600_GLOBAL_INIT		\
	(AST2600_I2CG_CTRL_NEW_REG |	\
	 AST2600_I2CG_CTRL_NEW_CLK_DIV)
> ...
> 
> > +#define I2CCG_DIV_CTRL 0xC6411208
> 
> Is it decimal? Is it combination of bitfields? Can you add a comment what is
> this magic?
> 
This have been comment in previous line. I will move above of this magic code.
/*
 * APB clk : 100Mhz
 * div	: scl		: baseclk [APB/((div/2) + 1)] : tBuf [1/bclk * 16]
 * I2CG10[31:24] base clk4 for i2c auto recovery timeout counter (0xC6)
 * I2CG10[23:16] base clk3 for Standard-mode (100Khz) min tBuf 4.7us
 * 0x3c : 100.8Khz	: 3.225Mhz					  : 4.96us
 * 0x3d : 99.2Khz	: 3.174Mhz					  : 5.04us
 * 0x3e : 97.65Khz	: 3.125Mhz					  : 5.12us
 * 0x40 : 97.75Khz	: 3.03Mhz					  : 5.28us
 * 0x41 : 99.5Khz	: 2.98Mhz					  : 5.36us (default)
 * I2CG10[15:8] base clk2 for Fast-mode (400Khz) min tBuf 1.3us
 * 0x12 : 400Khz	: 10Mhz						  : 1.6us
 * I2CG10[7:0] base clk1 for Fast-mode Plus (1Mhz) min tBuf 0.5us
 * 0x08 : 1Mhz		: 20Mhz						  : 0.8us
 */
> ...
> 
> > +struct ast2600_i2c_timing_table {
> > +	u32 divisor;
> > +	u32 timing;
> > +};
> 
> Is it even used?
> 
Will remove. 
> ...
> 
> > +enum xfer_mode {
> > +	BYTE_MODE = 0,
> 
> Why explicit assignment?

Will remove.
> 
> > +	BUFF_MODE,
> > +	DMA_MODE,
> > +};
> 
> ...
> 
> > +	base_clk1 = (i2c_bus->apb_clk * 10) / ((((clk_div_reg & 0xff) + 2) * 10) /
> 2);
> > +	base_clk2 = (i2c_bus->apb_clk * 10) /
> > +			(((((clk_div_reg >> 8) & 0xff) + 2) * 10) / 2);
> > +	base_clk3 = (i2c_bus->apb_clk * 10) /
> > +			(((((clk_div_reg >> 16) & 0xff) + 2) * 10) / 2);
> > +	base_clk4 = (i2c_bus->apb_clk * 10) /
> > +			(((((clk_div_reg >> 24) & 0xff) + 2) * 10) / 2);
> 
> The same equation is used per each byte of clk_div_reg? Can it be rewritten to
> avoid this and using loop, so you will have an array of base_clk to be filled?
> 
> Don't forget to use GENMASK().
> 
Will update for loop.
	for (i = 0; i < AST2600_NUM_CLK_DIV_BYTES; i++) {
		u32 byte_val = (clk_div_reg >> (i * 8)) & GENMASK(7, 0);
		base_clk[i] = (i2c_bus->apb_clk * 10) / ((byte_val + 2) * 5);
	}
> ...
> 
> > +	if ((i2c_bus->apb_clk / i2c_bus->bus_frequency) <= 32) {
> > +		baseclk_idx = 0;
> > +		divisor = DIV_ROUND_UP(i2c_bus->apb_clk,
> i2c_bus->bus_frequency);
> > +	} else if ((base_clk1 / i2c_bus->bus_frequency) <= 32) {
> > +		baseclk_idx = 1;
> > +		divisor = DIV_ROUND_UP(base_clk1, i2c_bus->bus_frequency);
> > +	} else if ((base_clk2 / i2c_bus->bus_frequency) <= 32) {
> > +		baseclk_idx = 2;
> > +		divisor = DIV_ROUND_UP(base_clk2, i2c_bus->bus_frequency);
> > +	} else if ((base_clk3 / i2c_bus->bus_frequency) <= 32) {
> > +		baseclk_idx = 3;
> > +		divisor = DIV_ROUND_UP(base_clk3, i2c_bus->bus_frequency);
> 
> Will be optimized with above suggestion, I believe.

Will up with previous
> 
> > +	} else {
> > +		baseclk_idx = 4;
> > +		divisor = DIV_ROUND_UP(base_clk4, i2c_bus->bus_frequency);
> > +		inc = 0;
> > +		while ((divisor + inc) > 32) {
> > +			inc |= divisor & 0x1;
> > +			divisor >>= 1;
> > +			baseclk_idx++;
> > +		}
> > +		divisor += inc;
> 
> I think the above loop can be rewritten to have better representation.
> 
Will up with previous

> > +	}
> 
> ...
> 
> > +	baseclk_idx &= 0xf;
> 
> GENMASK()?
> 
Will update 
> ...
> 
> > +	scl_low = ((divisor * 9) / 16) - 1;
> > +	scl_low = min_t(u32, scl_low, 0xf);
> 
> This can be done in one line. Also, why not 15?
> 
> ...
> 
> > +	scl_high = (divisor - scl_low - 2) & 0xf;
> 
> GENMASK()?
Will update

> 
> ...
> 
> > +	data = ((scl_high - 1) << 20) | (scl_high << 16) | (scl_low << 12) |
> > +(baseclk_idx);
> 
> Too many parentheses.
Update to 
data = ((scl_high - 1) << 20) | (scl_high << 16) | (scl_low << 12) | baseclk_idx;

> 
> ...
> 
> > +	/* due to master slave is common buffer, so need force the master stop
> not issue */
> > +	if (readl(i2c_bus->reg_base + AST2600_I2CM_CMD_STS) & 0xffff) {
> 
> GENMASK() ?
> 
> > +		writel(0, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
> > +		i2c_bus->cmd_err = -EBUSY;
> > +		writel(0, i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> > +		complete(&i2c_bus->cmd_complete);
> > +	}
> 
> ...
> 
> > +	/* send start */
> > +	dev_dbg(i2c_bus->dev, "[%d] %sing %d byte%s %s 0x%02x\n",
> > +		i2c_bus->msgs_index, msg->flags & I2C_M_RD ? "read" : "write",
> 
> str_read_write() ?
Sorry do you mean there have a function call str_read_write?
Can you point me where it is for refer?
> 
> > +		msg->len, msg->len > 1 ? "s" : "",
> > +		msg->flags & I2C_M_RD ? "from" : "to", msg->addr);
> 
> ...
> 
> > +				for (i = 0; i < xfer_len; i++) {
> > +					wbuf[i % 4] = msg->buf[i];
> > +					if (i % 4 == 3)
> > +						writel(*(u32 *)wbuf, i2c_bus->buf_base + i - 3);
> 
> Err.. There can be alignment issues.

Will update
> 
> > +				}
> > +				if (--i % 4 != 3)
> > +					writel(*(u32 *)wbuf, i2c_bus->buf_base + i - (i % 4));
> 
> The above code is ugly. Can you think about it and write in a better way?
Sorry, that is because the register only support for 4 byte align write.
That the reason I need put for byte write to 4 byte align write.
> 
> ...
> 
> > +				for (i = 0; i < xfer_len; i++) {
> > +					wbuf[i % 4] = msg->buf[i2c_bus->master_xfer_cnt + i];
> > +					if (i % 4 == 3)
> > +						writel(*(u32 *)wbuf, i2c_bus->buf_base + i - 3);
> > +				}
> > +				if (--i % 4 != 3)
> > +					writel(*(u32 *)wbuf, i2c_bus->buf_base + i - (i % 4));
> 
> Ditto.
Will update

> 
> ...
> 
> Do you have similar code pieces? Why not doing it in a separate function with
> parameters?
> 
I will think it to be MICRO function call.
> ...
> 
> > +	return ast2600_i2c_master_irq(i2c_bus) ? IRQ_HANDLED : IRQ_NONE;
> 
> IRQ_RETVAL() ?
Sorry, most return is handled or not handled.
Do you mean replace it just " return IRQ_RETVAL(ret);"

> 
> ...
> 
> > +	writel(0xfffffff, i2c_bus->reg_base + AST2600_I2CM_ISR);
> 
> GENMASK()
> 
Will Update
> ...
> 
> > +	writel(0xfffffff, i2c_bus->reg_base + AST2600_I2CS_ISR);
> 
> Ditto.
Will Update
> 
> > +	if (i2c_bus->mode == BYTE_MODE) {
> > +		writel(0xffff, i2c_bus->reg_base + AST2600_I2CS_IER);
> 
> Ditto.
Will Update
> 
> > +	} else {
> > +		/* Set interrupt generation of I2C slave controller */
> > +		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
> AST2600_I2CS_IER);
> > +	}
> 
> ...
> 
> > +	WARN_ON(!i2c_bus->slave);
> 
> Why?
It can be removed. 
> 
> ...
> 
> > +static const struct of_device_id ast2600_i2c_bus_of_table[] = {
> > +	{
> > +		.compatible = "aspeed,ast2600-i2cv2",
> > +	},
> > +	{}
> > +};
> 
> > +
> 
> Redundant blank line.
Will removed.
> 
> > +MODULE_DEVICE_TABLE(of, ast2600_i2c_bus_of_table);
> 
> ...
> 
> > +	i2c_bus = devm_kzalloc(dev, sizeof(*i2c_bus), GFP_KERNEL);
> > +	if (!i2c_bus)
> > +		return dev_err_probe(dev, -ENOMEM, "no memory allocated\n");
> 
> No. We do not print error message for ENOMEM.
> You homework to find why.
> 
Got it, will update.

> ...
> 
> > +	if (of_property_read_bool(pdev->dev.of_node, "aspeed,enable-dma"))
> 
> device_property_read_bool() ?
> 
> > +		i2c_bus->mode = DMA_MODE;
> 
> ...
> 
> > +	if (i2c_bus->mode == BUFF_MODE) {
> > +		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> > +		if (res && resource_size(res) >= 2) {
> > +			i2c_bus->buf_base = devm_ioremap_resource(dev, res);
> > +
> > +			if (!IS_ERR_OR_NULL(i2c_bus->buf_base))
> > +				i2c_bus->buf_size = resource_size(res) / 2;
> > +		} else {
> > +			i2c_bus->mode = BYTE_MODE;
> > +		}
> > +	}
> 
> Can be done without additional checks and with a simple call to
> devm_platform_ioremap_resource(). No?
> 
Sorry, I can't catch your point, can you guide me more about it?
> ...
> 
> > +	/* i2c timeout counter: use base clk4 1Mhz,
> > +	 * per unit: 1/(1000/4096) = 4096us
> > +	 */
> 
> Wrong multi-line style of the comment.
> 
Will update to
/*
 * i2c timeout counter: use base clk4 1Mhz,
 * per unit: 1/(1000/4096) = 4096us
 */
> ...
> 
> > +	ret = of_property_read_u32(dev->of_node,
> > +				   "i2c-scl-clk-low-timeout-us",
> > +				   &i2c_bus->timeout);
> > +	if (!ret)
> > +		i2c_bus->timeout /= 4096;
> 
> What is this and why I2C core timings (standard) can't be utilized here?
It is scl clk timout setting. That have been discuss with following.
https://lore.kernel.org/lkml/20230314221614.24205-1-andi.shyti@kernel.org/T/

> 
> ...
> 
> > +	ret = of_property_read_u32(dev->of_node, "clock-frequency",
> &i2c_bus->bus_frequency);
> > +	if (ret < 0) {
> > +		dev_warn(dev, "Could not read clock-frequency property\n");
> > +		i2c_bus->bus_frequency = 100000;
> > +	}
> 
> There are macro for standard speeds. Moreover, there is a function to parse
> properties, no need to open code.
> 
Will update
ret = of_property_read_u32(dev->of_node, "clock-frequency", &bus_freq);
if (ret < 0) {
    dev_warn(dev, "Could not read clock-frequency property\n");
    i2c_bus->bus_frequency = I2C_SPEED_STANDARD;
} else {
    i2c_bus->bus_frequency = bus_freq;
}
> ...
> 
> > +	i2c_bus->adap.dev.of_node = dev->of_node;
> 
> device_set_node()
> 
> ...
> 
> > +	if (of_property_read_bool(dev->of_node, "smbus-alert")) {
> 
> Doesn't core have already support for this?
Will remove it. 
> 
> > +		i2c_bus->alert_enable = true;
> > +		i2c_bus->ara = i2c_new_smbus_alert_device(&i2c_bus->adap,
> &i2c_bus->alert_data);
> > +		if (!i2c_bus->ara)
> > +			dev_warn(dev, "Failed to register ARA client\n");
> > +
> > +		writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER |
> AST2600_I2CM_SMBUS_ALT,
> > +		       i2c_bus->reg_base + AST2600_I2CM_IER);
> > +	} else {
> > +		i2c_bus->alert_enable = false;
> > +		/* Set interrupt generation of I2C master controller */
> > +		writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER,
> > +		       i2c_bus->reg_base + AST2600_I2CM_IER);
> > +	}
> 
> ...
> 
> > +	dev_info(dev, "%s [%d]: adapter [%d khz] mode [%d]\n",
> > +		 dev->of_node->name, i2c_bus->adap.nr, i2c_bus->bus_frequency /
> 1000,
> > +		 i2c_bus->mode);
> 
> Useless noise.
> 
Will remove it.

Thanks your review.

Best Regards,
Ryan Chen.
Andy Shevchenko May 8, 2023, 12:38 p.m. UTC | #3
On Sun, May 07, 2023 at 02:21:10AM +0000, Ryan Chen wrote:
> > On Sun, Apr 30, 2023 at 12:17:12PM +0800, Ryan Chen wrote:

...

> > > +#define AST2600_GLOBAL_INIT				\
> > > +			(AST2600_I2CG_CTRL_NEW_REG |	\
> > > +			AST2600_I2CG_CTRL_NEW_CLK_DIV)
> > 
> > Make just a one TAB and put the last two lines on the single one.
> 
> Update by following. 
> 
> #define AST2600_GLOBAL_INIT		\
> 	(AST2600_I2CG_CTRL_NEW_REG |	\
> 	 AST2600_I2CG_CTRL_NEW_CLK_DIV)

As I mentioned the last two can occupy a single line.

...

> > > +	/* send start */
> > > +	dev_dbg(i2c_bus->dev, "[%d] %sing %d byte%s %s 0x%02x\n",
> > > +		i2c_bus->msgs_index, msg->flags & I2C_M_RD ? "read" : "write",
> > 
> > str_read_write() ?
> Sorry do you mean there have a function call str_read_write?
> Can you point me where it is for refer?

string_helpers.h.

> > > +		msg->len, msg->len > 1 ? "s" : "",
> > > +		msg->flags & I2C_M_RD ? "from" : "to", msg->addr);

...

> > > +				if (--i % 4 != 3)
> > > +					writel(*(u32 *)wbuf, i2c_bus->buf_base + i - (i % 4));
> > 
> > The above code is ugly. Can you think about it and write in a better way?
> Sorry, that is because the register only support for 4 byte align write.
> That the reason I need put for byte write to 4 byte align write.

Yes, that's fine. The problem is in _how_ the driver does it. We have a lot of
helpers in the kernel to access unaligned data.

...

> > > +	return ast2600_i2c_master_irq(i2c_bus) ? IRQ_HANDLED : IRQ_NONE;
> > 
> > IRQ_RETVAL() ?
> Sorry, most return is handled or not handled.
> Do you mean replace it just " return IRQ_RETVAL(ret);"

Have you had a chance to look in the implementation of IRQ_RETVAL() ?
I believe if you do, you will find the answer to your question.

...

> > > +	if (i2c_bus->mode == BUFF_MODE) {
> > > +		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> > > +		if (res && resource_size(res) >= 2) {
> > > +			i2c_bus->buf_base = devm_ioremap_resource(dev, res);
> > > +
> > > +			if (!IS_ERR_OR_NULL(i2c_bus->buf_base))
> > > +				i2c_bus->buf_size = resource_size(res) / 2;
> > > +		} else {
> > > +			i2c_bus->mode = BYTE_MODE;
> > > +		}
> > > +	}
> > 
> > Can be done without additional checks and with a simple call to
> > devm_platform_ioremap_resource(). No?
> > 
> Sorry, I can't catch your point, can you guide me more about it?

	if (BUFF_MODE) {
		void __iomem buf_base;

		buf_base = devm_platform_ioremap_and_get_resource(pdev, 1, &res);
		if (IS_ERR(buf_base))
			mode = BYTE_MODE;
		else {
			->buf_base = buf_base;
			->buf_size = ...
		}
	}

...

> > > +	ret = of_property_read_u32(dev->of_node, "clock-frequency",
> > &i2c_bus->bus_frequency);
> > > +	if (ret < 0) {
> > > +		dev_warn(dev, "Could not read clock-frequency property\n");
> > > +		i2c_bus->bus_frequency = 100000;
> > > +	}
> > 
> > There are macro for standard speeds. Moreover, there is a function to parse
> > properties, no need to open code.
> > 
> Will update
> ret = of_property_read_u32(dev->of_node, "clock-frequency", &bus_freq);
> if (ret < 0) {
>     dev_warn(dev, "Could not read clock-frequency property\n");
>     i2c_bus->bus_frequency = I2C_SPEED_STANDARD;
> } else {
>     i2c_bus->bus_frequency = bus_freq;
> }

No, just use the I2C core API to fill this property in the specific i2c_timings
structure.
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 749710e22b4d..433ec2309441 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1924,6 +1924,15 @@  F:	Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2400-i2c-ic.
 F:	drivers/i2c/busses/i2c-aspeed.c
 F:	drivers/irqchip/irq-aspeed-i2c-ic.c
 
+ARM/ASPEED I2CV2 DRIVER
+M:	Ryan Chen <ryan_chen@aspeedtech.com>
+R:	Andrew Jeffery <andrew@aj.id.au>
+L:	linux-i2c@vger.kernel.org
+L:	openbmc@lists.ozlabs.org (moderated for non-subscribers)
+S:	Maintained
+F:	Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml
+F:	drivers/i2c/busses/i2c-ast2600.c
+
 ARM/ASPEED MACHINE SUPPORT
 M:	Joel Stanley <joel@jms.id.au>
 R:	Andrew Jeffery <andrew@aj.id.au>
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 7284206b278b..4f6935866257 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -389,6 +389,17 @@  config I2C_ALTERA
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-altera.
 
+config I2C_AST2600
+	tristate "Aspeed I2C v2 Controller"
+	depends on ARCH_ASPEED || COMPILE_TEST
+	select I2C_SMBUS
+	help
+	  If you say yes to this option, support will be included for the
+	  Aspeed I2C controller with new register set.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-ast2600.
+
 config I2C_ASPEED
 	tristate "Aspeed I2C Controller"
 	depends on ARCH_ASPEED || COMPILE_TEST
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index c5cac15f075c..d0ab4d45781c 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -38,6 +38,7 @@  obj-$(CONFIG_I2C_POWERMAC)	+= i2c-powermac.o
 obj-$(CONFIG_I2C_ALTERA)	+= i2c-altera.o
 obj-$(CONFIG_I2C_AMD_MP2)	+= i2c-amd-mp2-pci.o i2c-amd-mp2-plat.o
 obj-$(CONFIG_I2C_ASPEED)	+= i2c-aspeed.o
+obj-$(CONFIG_I2C_AST2600)	+= i2c-ast2600.o
 obj-$(CONFIG_I2C_AT91)		+= i2c-at91.o
 i2c-at91-objs			:= i2c-at91-core.o i2c-at91-master.o
 ifeq ($(CONFIG_I2C_AT91_SLAVE_EXPERIMENTAL),y)
diff --git a/drivers/i2c/busses/i2c-ast2600.c b/drivers/i2c/busses/i2c-ast2600.c
new file mode 100644
index 000000000000..405405373e1c
--- /dev/null
+++ b/drivers/i2c/busses/i2c-ast2600.c
@@ -0,0 +1,1596 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ASPEED AST2600 new register set I2C controller driver
+ *
+ * Copyright (C) ASPEED Technology Inc.
+ */
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/reset.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/completion.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/of_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/i2c-smbus.h>
+
+/*
+ * APB clk : 100Mhz
+ * div	: scl		: baseclk [APB/((div/2) + 1)] : tBuf [1/bclk * 16]
+ * I2CG10[31:24] base clk4 for i2c auto recovery timeout counter (0xC6)
+ * I2CG10[23:16] base clk3 for Standard-mode (100Khz) min tBuf 4.7us
+ * 0x3c : 100.8Khz	: 3.225Mhz					  : 4.96us
+ * 0x3d : 99.2Khz	: 3.174Mhz					  : 5.04us
+ * 0x3e : 97.65Khz	: 3.125Mhz					  : 5.12us
+ * 0x40 : 97.75Khz	: 3.03Mhz					  : 5.28us
+ * 0x41 : 99.5Khz	: 2.98Mhz					  : 5.36us (default)
+ * I2CG10[15:8] base clk2 for Fast-mode (400Khz) min tBuf 1.3us
+ * 0x12 : 400Khz	: 10Mhz						  : 1.6us
+ * I2CG10[7:0] base clk1 for Fast-mode Plus (1Mhz) min tBuf 0.5us
+ * 0x08 : 1Mhz		: 20Mhz						  : 0.8us
+ */
+#define AST2600_I2CG_ISR			0x00
+#define AST2600_I2CG_SLAVE_ISR		0x04
+#define AST2600_I2CG_OWNER		0x08
+#define AST2600_I2CG_CTRL		0x0C
+#define AST2600_I2CG_CLK_DIV_CTRL	0x10
+
+#define AST2600_I2CG_SLAVE_PKT_NAK	BIT(4)
+#define AST2600_I2CG_M_S_SEPARATE_INTR	BIT(3)
+#define AST2600_I2CG_CTRL_NEW_REG	BIT(2)
+#define AST2600_I2CG_CTRL_NEW_CLK_DIV	BIT(1)
+
+#define AST2600_GLOBAL_INIT				\
+			(AST2600_I2CG_CTRL_NEW_REG |	\
+			AST2600_I2CG_CTRL_NEW_CLK_DIV)
+#define I2CCG_DIV_CTRL 0xC6411208
+
+/* 0x00 : I2CC Master/Slave Function Control Register  */
+#define AST2600_I2CC_FUN_CTRL		0x00
+#define AST2600_I2CC_SLAVE_ADDR_RX_EN		BIT(20)
+#define AST2600_I2CC_MASTER_RETRY_MASK		GENMASK(19, 18)
+#define AST2600_I2CC_MASTER_RETRY(x)		(((x) & GENMASK(1, 0)) << 18)
+#define AST2600_I2CC_BUS_AUTO_RELEASE		BIT(17)
+#define AST2600_I2CC_M_SDA_LOCK_EN			BIT(16)
+#define AST2600_I2CC_MULTI_MASTER_DIS		BIT(15)
+#define AST2600_I2CC_M_SCL_DRIVE_EN			BIT(14)
+#define AST2600_I2CC_MSB_STS				BIT(9)
+#define AST2600_I2CC_SDA_DRIVE_1T_EN		BIT(8)
+#define AST2600_I2CC_M_SDA_DRIVE_1T_EN		BIT(7)
+#define AST2600_I2CC_M_HIGH_SPEED_EN		BIT(6)
+/* reserver 5 : 2 */
+#define AST2600_I2CC_SLAVE_EN			BIT(1)
+#define AST2600_I2CC_MASTER_EN			BIT(0)
+
+/* 0x04 : I2CC Master/Slave Clock and AC Timing Control Register #1 */
+#define AST2600_I2CC_AC_TIMING		0x04
+#define AST2600_I2CC_TTIMEOUT(x)			(((x) & GENMASK(4, 0)) << 24)
+#define AST2600_I2CC_TCKHIGHMIN(x)			(((x) & GENMASK(3, 0)) << 20)
+#define AST2600_I2CC_TCKHIGH(x)			(((x) & GENMASK(3, 0)) << 16)
+#define AST2600_I2CC_TCKLOW(x)			(((x) & GENMASK(3, 0)) << 12)
+#define AST2600_I2CC_THDDAT(x)			(((x) & GENMASK(1, 0)) << 10)
+#define AST2600_I2CC_TOUTBASECLK(x)			(((x) & GENMASK(1, 0)) << 8)
+#define AST2600_I2CC_TBASECLK(x)			((x) & GENMASK(3, 0))
+
+/* 0x08 : I2CC Master/Slave Transmit/Receive Byte Buffer Register */
+#define AST2600_I2CC_STS_AND_BUFF		0x08
+#define AST2600_I2CC_TX_DIR_MASK			GENMASK(31, 29)
+#define AST2600_I2CC_SDA_OE				BIT(28)
+#define AST2600_I2CC_SDA_O				BIT(27)
+#define AST2600_I2CC_SCL_OE				BIT(26)
+#define AST2600_I2CC_SCL_O				BIT(25)
+
+#define AST2600_I2CC_SCL_LINE_STS			BIT(18)
+#define AST2600_I2CC_SDA_LINE_STS			BIT(17)
+#define AST2600_I2CC_BUS_BUSY_STS			BIT(16)
+
+#define AST2600_I2CC_GET_RX_BUFF(x)			(((x) >> 8) & GENMASK(7, 0))
+
+/* 0x0C : I2CC Master/Slave Pool Buffer Control Register  */
+#define AST2600_I2CC_BUFF_CTRL		0x0C
+#define AST2600_I2CC_GET_RX_BUF_LEN(x)		(((x) >> 24) & GENMASK(5, 0))
+#define AST2600_I2CC_SET_RX_BUF_LEN(x)		(((((x) - 1) & GENMASK(4, 0)) << 16) | BIT(0))
+#define AST2600_I2CC_SET_TX_BUF_LEN(x)		(((((x) - 1) & GENMASK(4, 0)) << 8) | BIT(0))
+#define AST2600_I2CC_GET_TX_BUF_LEN(x)		((((x) >> 8) & GENMASK(4, 0)) + 1)
+
+/* 0x10 : I2CM Master Interrupt Control Register */
+#define AST2600_I2CM_IER			0x10
+/* 0x14 : I2CM Master Interrupt Status Register   : WC */
+#define AST2600_I2CM_ISR			0x14
+
+#define AST2600_I2CM_PKT_TIMEOUT			BIT(18)
+#define AST2600_I2CM_PKT_ERROR			BIT(17)
+#define AST2600_I2CM_PKT_DONE			BIT(16)
+
+#define AST2600_I2CM_BUS_RECOVER_FAIL		BIT(15)
+#define AST2600_I2CM_SDA_DL_TO			BIT(14)
+#define AST2600_I2CM_BUS_RECOVER			BIT(13)
+#define AST2600_I2CM_SMBUS_ALT			BIT(12)
+
+#define AST2600_I2CM_SCL_LOW_TO			BIT(6)
+#define AST2600_I2CM_ABNORMAL			BIT(5)
+#define AST2600_I2CM_NORMAL_STOP			BIT(4)
+#define AST2600_I2CM_ARBIT_LOSS			BIT(3)
+#define AST2600_I2CM_RX_DONE			BIT(2)
+#define AST2600_I2CM_TX_NAK				BIT(1)
+#define AST2600_I2CM_TX_ACK				BIT(0)
+
+/* 0x18 : I2CM Master Command/Status Register   */
+#define AST2600_I2CM_CMD_STS		0x18
+#define AST2600_I2CM_PKT_ADDR(x)			(((x) & GENMASK(6, 0)) << 24)
+#define AST2600_I2CM_PKT_EN				BIT(16)
+#define AST2600_I2CM_SDA_OE_OUT_DIR			BIT(15)
+#define AST2600_I2CM_SDA_O_OUT_DIR			BIT(14)
+#define AST2600_I2CM_SCL_OE_OUT_DIR			BIT(13)
+#define AST2600_I2CM_SCL_O_OUT_DIR			BIT(12)
+#define AST2600_I2CM_RECOVER_CMD_EN			BIT(11)
+
+#define AST2600_I2CM_RX_DMA_EN			BIT(9)
+#define AST2600_I2CM_TX_DMA_EN			BIT(8)
+/* Command Bit */
+#define AST2600_I2CM_RX_BUFF_EN			BIT(7)
+#define AST2600_I2CM_TX_BUFF_EN			BIT(6)
+#define AST2600_I2CM_STOP_CMD			BIT(5)
+#define AST2600_I2CM_RX_CMD_LAST			BIT(4)
+#define AST2600_I2CM_RX_CMD				BIT(3)
+
+#define AST2600_I2CM_TX_CMD				BIT(1)
+#define AST2600_I2CM_START_CMD			BIT(0)
+
+/* 0x1C : I2CM Master DMA Transfer Length Register	 */
+#define AST2600_I2CM_DMA_LEN		0x1C
+/* Tx Rx support length 1 ~ 4096 */
+#define AST2600_I2CM_SET_RX_DMA_LEN(x)	((((x) & GENMASK(11, 0)) << 16) | BIT(31))
+#define AST2600_I2CM_SET_TX_DMA_LEN(x)	(((x) & GENMASK(11, 0)) | BIT(15))
+
+/* 0x20 : I2CS Slave Interrupt Control Register   */
+#define AST2600_I2CS_IER			0x20
+/* 0x24 : I2CS Slave Interrupt Status Register	 */
+#define AST2600_I2CS_ISR			0x24
+
+#define AST2600_I2CS_ADDR_INDICATE_MASK	GENMASK(31, 30)
+#define AST2600_I2CS_SLAVE_PENDING			BIT(29)
+
+#define AST2600_I2CS_WAIT_TX_DMA			BIT(25)
+#define AST2600_I2CS_WAIT_RX_DMA			BIT(24)
+
+#define AST2600_I2CS_ADDR3_NAK			BIT(22)
+#define AST2600_I2CS_ADDR2_NAK			BIT(21)
+#define AST2600_I2CS_ADDR1_NAK			BIT(20)
+
+#define AST2600_I2CS_ADDR_MASK			GENMASK(19, 18)
+#define AST2600_I2CS_PKT_ERROR			BIT(17)
+#define AST2600_I2CS_PKT_DONE			BIT(16)
+#define AST2600_I2CS_INACTIVE_TO			BIT(15)
+
+#define AST2600_I2CS_SLAVE_MATCH			BIT(7)
+#define AST2600_I2CS_ABNOR_STOP			BIT(5)
+#define AST2600_I2CS_STOP				BIT(4)
+#define AST2600_I2CS_RX_DONE_NAK			BIT(3)
+#define AST2600_I2CS_RX_DONE			BIT(2)
+#define AST2600_I2CS_TX_NAK				BIT(1)
+#define AST2600_I2CS_TX_ACK				BIT(0)
+
+/* 0x28 : I2CS Slave CMD/Status Register   */
+#define AST2600_I2CS_CMD_STS		0x28
+#define AST2600_I2CS_ACTIVE_ALL			GENMASK(18, 17)
+#define AST2600_I2CS_PKT_MODE_EN			BIT(16)
+#define AST2600_I2CS_AUTO_NAK_NOADDR		BIT(15)
+#define AST2600_I2CS_AUTO_NAK_EN			BIT(14)
+
+#define AST2600_I2CS_ALT_EN				BIT(10)
+#define AST2600_I2CS_RX_DMA_EN			BIT(9)
+#define AST2600_I2CS_TX_DMA_EN			BIT(8)
+#define AST2600_I2CS_RX_BUFF_EN			BIT(7)
+#define AST2600_I2CS_TX_BUFF_EN			BIT(6)
+#define AST2600_I2CS_RX_CMD_LAST			BIT(4)
+
+#define AST2600_I2CS_TX_CMD				BIT(2)
+
+#define AST2600_I2CS_DMA_LEN		0x2C
+#define AST2600_I2CS_SET_RX_DMA_LEN(x)	(((((x) - 1) & GENMASK(11, 0)) << 16) | BIT(31))
+#define AST2600_I2CS_RX_DMA_LEN_MASK	(GENMASK(11, 0) << 16)
+
+#define AST2600_I2CS_SET_TX_DMA_LEN(x)	((((x) - 1) & GENMASK(11, 0)) | BIT(15))
+#define AST2600_I2CS_TX_DMA_LEN_MASK	GENMASK(11, 0)
+
+/* I2CM Master DMA Tx Buffer Register   */
+#define AST2600_I2CM_TX_DMA			0x30
+/* I2CM Master DMA Rx Buffer Register	*/
+#define AST2600_I2CM_RX_DMA			0x34
+/* I2CS Slave DMA Tx Buffer Register   */
+#define AST2600_I2CS_TX_DMA			0x38
+/* I2CS Slave DMA Rx Buffer Register   */
+#define AST2600_I2CS_RX_DMA			0x3C
+
+#define AST2600_I2CS_ADDR_CTRL		0x40
+
+#define	AST2600_I2CS_ADDR3_MASK		GENMASK(22, 16)
+#define	AST2600_I2CS_ADDR2_MASK		GENMASK(14, 8)
+#define	AST2600_I2CS_ADDR1_MASK		GENMASK(6, 0)
+
+#define AST2600_I2CM_DMA_LEN_STS		0x48
+#define AST2600_I2CS_DMA_LEN_STS		0x4C
+
+#define AST2600_I2C_GET_TX_DMA_LEN(x)		((x) & GENMASK(12, 0))
+#define AST2600_I2C_GET_RX_DMA_LEN(x)		(((x) >> 16) & GENMASK(12, 0))
+
+/* 0x40 : Slave Device Address Register */
+#define AST2600_I2CS_ADDR3_ENABLE			BIT(23)
+#define AST2600_I2CS_ADDR3(x)			((x) << 16)
+#define AST2600_I2CS_ADDR2_ENABLE			BIT(15)
+#define AST2600_I2CS_ADDR2(x)			((x) << 8)
+#define AST2600_I2CS_ADDR1_ENABLE			BIT(7)
+#define AST2600_I2CS_ADDR1(x)			(x)
+
+#define I2C_SLAVE_MSG_BUF_SIZE		256
+
+#define AST2600_I2C_DMA_SIZE		4096
+
+#define MASTER_TRIGGER_LAST_STOP	(AST2600_I2CM_RX_CMD_LAST | AST2600_I2CM_STOP_CMD)
+#define SLAVE_TRIGGER_CMD	(AST2600_I2CS_ACTIVE_ALL | AST2600_I2CS_PKT_MODE_EN)
+
+#define AST_I2C_TIMEOUT_CLK		0x2
+
+struct ast2600_i2c_timing_table {
+	u32 divisor;
+	u32 timing;
+};
+
+enum xfer_mode {
+	BYTE_MODE = 0,
+	BUFF_MODE,
+	DMA_MODE,
+};
+
+struct ast2600_i2c_bus {
+	struct i2c_adapter		adap;
+	struct device			*dev;
+	void __iomem			*reg_base;
+	struct regmap			*global_regs;
+	struct reset_control		*rst;
+	int				irq;
+	enum xfer_mode			mode;
+	struct clk			*clk;
+	u32				apb_clk;
+	u32				bus_frequency;
+	int				slave_operate;
+	u32				timeout;
+	/* smbus alert */
+	bool			alert_enable;
+	struct i2c_smbus_alert_setup	alert_data;
+	struct i2c_client		*ara;
+	/* Multi-master */
+	bool				multi_master;
+	/* master structure */
+	int				cmd_err;
+	struct completion		cmd_complete;
+	struct i2c_msg			*msgs;
+	size_t				buf_index;
+	/* cur xfer msgs index*/
+	int				msgs_index;
+	int				msgs_count;
+	u8				*master_safe_buf;
+	dma_addr_t			master_dma_addr;
+	/*total xfer count */
+	int				master_xfer_cnt;
+	/* Buffer mode */
+	void __iomem			*buf_base;
+	size_t				buf_size;
+	/* Slave structure */
+	int				slave_xfer_len;
+	int				slave_xfer_cnt;
+#ifdef CONFIG_I2C_SLAVE
+	unsigned char			*slave_dma_buf;
+	dma_addr_t			slave_dma_addr;
+	struct i2c_client		*slave;
+#endif
+};
+
+static u32 ast2600_select_i2c_clock(struct ast2600_i2c_bus *i2c_bus)
+{
+	unsigned long base_clk1;
+	unsigned long base_clk2;
+	unsigned long base_clk3;
+	unsigned long base_clk4;
+	int baseclk_idx;
+	u32 clk_div_reg;
+	u32 scl_low;
+	u32 scl_high;
+	int divisor;
+	int inc = 0;
+	u32 data;
+
+	regmap_read(i2c_bus->global_regs, AST2600_I2CG_CLK_DIV_CTRL, &clk_div_reg);
+	base_clk1 = (i2c_bus->apb_clk * 10) / ((((clk_div_reg & 0xff) + 2) * 10) / 2);
+	base_clk2 = (i2c_bus->apb_clk * 10) /
+			(((((clk_div_reg >> 8) & 0xff) + 2) * 10) / 2);
+	base_clk3 = (i2c_bus->apb_clk * 10) /
+			(((((clk_div_reg >> 16) & 0xff) + 2) * 10) / 2);
+	base_clk4 = (i2c_bus->apb_clk * 10) /
+			(((((clk_div_reg >> 24) & 0xff) + 2) * 10) / 2);
+
+	if ((i2c_bus->apb_clk / i2c_bus->bus_frequency) <= 32) {
+		baseclk_idx = 0;
+		divisor = DIV_ROUND_UP(i2c_bus->apb_clk, i2c_bus->bus_frequency);
+	} else if ((base_clk1 / i2c_bus->bus_frequency) <= 32) {
+		baseclk_idx = 1;
+		divisor = DIV_ROUND_UP(base_clk1, i2c_bus->bus_frequency);
+	} else if ((base_clk2 / i2c_bus->bus_frequency) <= 32) {
+		baseclk_idx = 2;
+		divisor = DIV_ROUND_UP(base_clk2, i2c_bus->bus_frequency);
+	} else if ((base_clk3 / i2c_bus->bus_frequency) <= 32) {
+		baseclk_idx = 3;
+		divisor = DIV_ROUND_UP(base_clk3, i2c_bus->bus_frequency);
+	} else {
+		baseclk_idx = 4;
+		divisor = DIV_ROUND_UP(base_clk4, i2c_bus->bus_frequency);
+		inc = 0;
+		while ((divisor + inc) > 32) {
+			inc |= divisor & 0x1;
+			divisor >>= 1;
+			baseclk_idx++;
+		}
+		divisor += inc;
+	}
+	divisor = min_t(int, divisor, 32);
+	baseclk_idx &= 0xf;
+	scl_low = ((divisor * 9) / 16) - 1;
+	scl_low = min_t(u32, scl_low, 0xf);
+	scl_high = (divisor - scl_low - 2) & 0xf;
+	/* Divisor : Base Clock : tCKHighMin : tCK High : tCK Low  */
+	data = ((scl_high - 1) << 20) | (scl_high << 16) | (scl_low << 12) | (baseclk_idx);
+	if (i2c_bus->timeout) {
+		data |= AST2600_I2CC_TOUTBASECLK(AST_I2C_TIMEOUT_CLK);
+		data |= AST2600_I2CC_TTIMEOUT(i2c_bus->timeout);
+	}
+
+	return data;
+}
+
+static u8 ast2600_i2c_recover_bus(struct ast2600_i2c_bus *i2c_bus)
+{
+	int ret = 0;
+	u32 ctrl;
+	u32 state;
+	int r;
+
+	dev_dbg(i2c_bus->dev, "%d-bus recovery bus [%x]\n", i2c_bus->adap.nr,
+		readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
+
+	ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+	writel(ctrl & ~(AST2600_I2CC_MASTER_EN | AST2600_I2CC_SLAVE_EN),
+	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+	writel(readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL) | AST2600_I2CC_MASTER_EN,
+	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+	reinit_completion(&i2c_bus->cmd_complete);
+	i2c_bus->cmd_err = 0;
+
+	/* Check 0x14's SDA and SCL status */
+	state = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+	if (!(state & AST2600_I2CC_SDA_LINE_STS) && (state & AST2600_I2CC_SCL_LINE_STS)) {
+		writel(AST2600_I2CM_RECOVER_CMD_EN, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+		r = wait_for_completion_timeout(&i2c_bus->cmd_complete, i2c_bus->adap.timeout);
+		if (r == 0) {
+			dev_dbg(i2c_bus->dev, "recovery timed out\n");
+			ret = -ETIMEDOUT;
+		} else {
+			if (i2c_bus->cmd_err) {
+				dev_dbg(i2c_bus->dev, "recovery error\n");
+				ret = -EPROTO;
+			}
+		}
+	}
+
+	dev_dbg(i2c_bus->dev, "Recovery done [%x]\n",
+		readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
+	if (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) & AST2600_I2CC_BUS_BUSY_STS) {
+		dev_dbg(i2c_bus->dev, "Can't recover bus [%x]\n",
+			readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
+		ret = -EPROTO;
+	}
+
+	writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+	return ret;
+}
+
+#ifdef CONFIG_I2C_SLAVE
+static void ast2600_i2c_slave_packet_dma_irq(struct ast2600_i2c_bus *i2c_bus, u32 sts)
+{
+	int slave_rx_len;
+	u32 cmd = 0;
+	u8 value;
+	int i;
+
+	sts &= ~(AST2600_I2CS_SLAVE_PENDING);
+	/* Handle i2c slave timeout condition */
+	if (AST2600_I2CS_INACTIVE_TO & sts) {
+		cmd = SLAVE_TRIGGER_CMD;
+		cmd |= AST2600_I2CS_RX_DMA_EN;
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_ISR);
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		return;
+	}
+
+	sts &= ~(AST2600_I2CS_PKT_DONE | AST2600_I2CS_PKT_ERROR);
+
+	switch (sts) {
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_RX_DMA:
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+		slave_rx_len = AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
+						      AST2600_I2CS_DMA_LEN_STS));
+		for (i = 0; i < slave_rx_len; i++) {
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED,
+					&i2c_bus->slave_dma_buf[i]);
+		}
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_STOP:
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE_NAK |
+			AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_RX_DMA |
+			AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_RX_DONE_NAK | AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_STOP:
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+		if (sts & AST2600_I2CS_SLAVE_MATCH)
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+
+		slave_rx_len = AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
+						      AST2600_I2CS_DMA_LEN_STS));
+		for (i = 0; i < slave_rx_len; i++) {
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED,
+					&i2c_bus->slave_dma_buf[i]);
+		}
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		if (sts & AST2600_I2CS_STOP)
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
+		break;
+
+	/* it is Mw data Mr coming -> it need send tx */
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_TX_DMA:
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_TX_DMA:
+		/* it should be repeat start read */
+		if (sts & AST2600_I2CS_SLAVE_MATCH)
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+
+		slave_rx_len = AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
+						      AST2600_I2CS_DMA_LEN_STS));
+		for (i = 0; i < slave_rx_len; i++) {
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED,
+					&i2c_bus->slave_dma_buf[i]);
+		}
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED,
+				&i2c_bus->slave_dma_buf[0]);
+		writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
+		writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_TX_DMA:
+		/* First Start read */
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED,
+				&i2c_bus->slave_dma_buf[0]);
+		writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
+		break;
+	case AST2600_I2CS_WAIT_TX_DMA:
+		/* it should be next start read */
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_PROCESSED,
+				&i2c_bus->slave_dma_buf[0]);
+		writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
+		writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
+		break;
+	case AST2600_I2CS_TX_NAK | AST2600_I2CS_STOP:
+		/* it just tx complete */
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
+		cmd = 0;
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+		break;
+	case AST2600_I2CS_STOP:
+		cmd = 0;
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		break;
+	default:
+		dev_dbg(i2c_bus->dev, "unhandled slave isr case %x, sts %x\n", sts,
+			readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
+		break;
+	}
+
+	if (cmd)
+		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+	writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_ISR);
+	readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
+}
+
+static void ast2600_i2c_slave_packet_buff_irq(struct ast2600_i2c_bus *i2c_bus, u32 sts)
+{
+	int slave_rx_len = 0;
+	u32 cmd = 0;
+	u8 value;
+	int i;
+
+	/* due to master slave is common buffer, so need force the master stop not issue */
+	if (readl(i2c_bus->reg_base + AST2600_I2CM_CMD_STS) & 0xffff) {
+		writel(0, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+		i2c_bus->cmd_err = -EBUSY;
+		writel(0, i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		complete(&i2c_bus->cmd_complete);
+	}
+
+	/* Handle i2c slave timeout condition */
+	if (AST2600_I2CS_INACTIVE_TO & sts) {
+		writel(SLAVE_TRIGGER_CMD, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_ISR);
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		i2c_bus->slave_operate = 0;
+		return;
+	}
+
+	sts &= ~(AST2600_I2CS_PKT_DONE | AST2600_I2CS_PKT_ERROR);
+
+	if (sts & AST2600_I2CS_SLAVE_MATCH)
+		i2c_bus->slave_operate = 1;
+
+	switch (sts) {
+	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_WAIT_RX_DMA |
+		 AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_SLAVE_PENDING |
+		 AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_SLAVE_PENDING |
+		 AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_STOP:
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		fallthrough;
+	case AST2600_I2CS_SLAVE_PENDING |
+		 AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
+	case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
+	case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH:
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+		cmd = SLAVE_TRIGGER_CMD;
+		if (sts & AST2600_I2CS_RX_DONE) {
+			slave_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+							       AST2600_I2CC_BUFF_CTRL));
+			for (i = 0; i < slave_rx_len; i++) {
+				value = readb(i2c_bus->buf_base + 0x10 + i);
+				i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED, &value);
+			}
+		}
+		if (readl(i2c_bus->reg_base + AST2600_I2CS_CMD_STS) & AST2600_I2CS_RX_BUFF_EN)
+			cmd = 0;
+		else
+			cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_BUFF_EN;
+
+		writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		break;
+	case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_RX_DONE:
+		cmd = SLAVE_TRIGGER_CMD;
+		slave_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+						       AST2600_I2CC_BUFF_CTRL));
+		for (i = 0; i < slave_rx_len; i++) {
+			value = readb(i2c_bus->buf_base + 0x10 + i);
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED, &value);
+		}
+		cmd |= AST2600_I2CS_RX_BUFF_EN;
+		writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		break;
+	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_WAIT_RX_DMA |
+				AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+		cmd = SLAVE_TRIGGER_CMD;
+		slave_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+								 AST2600_I2CC_BUFF_CTRL));
+		for (i = 0; i < slave_rx_len; i++) {
+			value = readb(i2c_bus->buf_base + 0x10 + i);
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED, &value);
+		}
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		cmd |= AST2600_I2CS_RX_BUFF_EN;
+		writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		break;
+	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+		cmd = SLAVE_TRIGGER_CMD;
+		slave_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+								 AST2600_I2CC_BUFF_CTRL));
+		for (i = 0; i < slave_rx_len; i++) {
+			value = readb(i2c_bus->buf_base + 0x10 + i);
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED, &value);
+		}
+		/* workaround for avoid next start with len != 0 */
+		writel(BIT(0), i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		break;
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+		cmd = SLAVE_TRIGGER_CMD;
+		slave_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+								 AST2600_I2CC_BUFF_CTRL));
+		for (i = 0; i < slave_rx_len; i++) {
+			value = readb(i2c_bus->buf_base + 0x10 + i);
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED, &value);
+		}
+		/* workaround for avoid next start with len != 0 */
+		writel(BIT(0), i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		break;
+	case AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_SLAVE_MATCH:
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
+		writeb(value, i2c_bus->buf_base);
+		writel(AST2600_I2CC_SET_TX_BUF_LEN(1),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_BUFF_EN;
+		break;
+	case AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_RX_DONE:
+	case AST2600_I2CS_WAIT_TX_DMA:
+		if (sts & AST2600_I2CS_RX_DONE) {
+			slave_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+							AST2600_I2CC_BUFF_CTRL));
+			for (i = 0; i < slave_rx_len; i++) {
+				value = readb(i2c_bus->buf_base + 0x10 + i);
+				i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED, &value);
+			}
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
+		} else {
+			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
+		}
+		writeb(value, i2c_bus->buf_base);
+		writel(AST2600_I2CC_SET_TX_BUF_LEN(1),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_BUFF_EN;
+		break;
+	/* workaround : trigger the cmd twice to fix next state keep 1000000 */
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_BUFF_EN;
+		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+		break;
+
+	case AST2600_I2CS_TX_NAK | AST2600_I2CS_STOP:
+	case AST2600_I2CS_STOP:
+		cmd = SLAVE_TRIGGER_CMD;
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		break;
+	default:
+		dev_dbg(i2c_bus->dev, "unhandled slave isr case %x, sts %x\n", sts,
+			readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
+		break;
+	}
+
+	if (cmd)
+		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+	writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_ISR);
+	readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
+
+	if ((sts & AST2600_I2CS_STOP) && !(sts & AST2600_I2CS_SLAVE_PENDING))
+		i2c_bus->slave_operate = 0;
+}
+
+static void ast2600_i2c_slave_byte_irq(struct ast2600_i2c_bus *i2c_bus, u32 sts)
+{
+	u32 i2c_buff = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+	u32 cmd = AST2600_I2CS_ACTIVE_ALL;
+	u8 byte_data;
+	u8 value;
+
+	switch (sts) {
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+		/* first address match is address */
+		byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
+		break;
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
+		byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED, &byte_data);
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_TX_DMA:
+		cmd |= AST2600_I2CS_TX_CMD;
+		byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED, &byte_data);
+		writel(byte_data, i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+		break;
+	case AST2600_I2CS_TX_ACK | AST2600_I2CS_WAIT_TX_DMA:
+		cmd |= AST2600_I2CS_TX_CMD;
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_PROCESSED, &byte_data);
+		writel(byte_data, i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+		break;
+	case AST2600_I2CS_STOP:
+	case AST2600_I2CS_STOP | AST2600_I2CS_TX_NAK:
+		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
+		break;
+	default:
+		dev_dbg(i2c_bus->dev, "unhandled pkt isr %x\n", sts);
+		break;
+	}
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+	writel(sts, i2c_bus->reg_base + AST2600_I2CS_ISR);
+	readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
+}
+
+static int ast2600_i2c_slave_irq(struct ast2600_i2c_bus *i2c_bus)
+{
+	u32 ier = readl(i2c_bus->reg_base + AST2600_I2CS_IER);
+	u32 isr = readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
+
+	if (!(isr & ier))
+		return 0;
+
+	/* Slave interrupt coming after Master package done
+	 * So need handle master first.
+	 */
+	if (readl(i2c_bus->reg_base + AST2600_I2CM_ISR) & AST2600_I2CM_PKT_DONE)
+		return 0;
+
+	isr &= ~(AST2600_I2CS_ADDR_INDICATE_MASK);
+
+	if (AST2600_I2CS_ADDR1_NAK & isr)
+		isr &= ~AST2600_I2CS_ADDR1_NAK;
+
+	if (AST2600_I2CS_ADDR2_NAK & isr)
+		isr &= ~AST2600_I2CS_ADDR2_NAK;
+
+	if (AST2600_I2CS_ADDR3_NAK & isr)
+		isr &= ~AST2600_I2CS_ADDR3_NAK;
+
+	if (AST2600_I2CS_ADDR_MASK & isr)
+		isr &= ~AST2600_I2CS_ADDR_MASK;
+
+	if (AST2600_I2CS_PKT_DONE & isr) {
+		if (i2c_bus->mode == DMA_MODE)
+			ast2600_i2c_slave_packet_dma_irq(i2c_bus, isr);
+		else
+			ast2600_i2c_slave_packet_buff_irq(i2c_bus, isr);
+	} else {
+		ast2600_i2c_slave_byte_irq(i2c_bus, isr);
+	}
+
+	return 1;
+}
+#endif
+
+static int ast2600_i2c_do_start(struct ast2600_i2c_bus *i2c_bus)
+{
+	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+	int xfer_len = 0;
+	int i;
+	u32 cmd;
+
+	cmd = AST2600_I2CM_PKT_EN | AST2600_I2CM_PKT_ADDR(msg->addr) | AST2600_I2CM_START_CMD;
+
+	/* send start */
+	dev_dbg(i2c_bus->dev, "[%d] %sing %d byte%s %s 0x%02x\n",
+		i2c_bus->msgs_index, msg->flags & I2C_M_RD ? "read" : "write",
+		msg->len, msg->len > 1 ? "s" : "",
+		msg->flags & I2C_M_RD ? "from" : "to", msg->addr);
+
+	i2c_bus->master_xfer_cnt = 0;
+	i2c_bus->buf_index = 0;
+
+	if (msg->flags & I2C_M_RD) {
+		cmd |= AST2600_I2CM_RX_CMD;
+		if (i2c_bus->mode == DMA_MODE) {
+			/* dma mode */
+			cmd |= AST2600_I2CM_RX_DMA_EN;
+
+			if (msg->flags & I2C_M_RECV_LEN) {
+				xfer_len = 1;
+			} else {
+				if (msg->len > AST2600_I2C_DMA_SIZE) {
+					xfer_len = AST2600_I2C_DMA_SIZE;
+				} else {
+					xfer_len = msg->len;
+					if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+						cmd |= MASTER_TRIGGER_LAST_STOP;
+				}
+			}
+			writel(AST2600_I2CM_SET_RX_DMA_LEN(xfer_len - 1),
+			       i2c_bus->reg_base + AST2600_I2CM_DMA_LEN);
+			i2c_bus->master_safe_buf = i2c_get_dma_safe_msg_buf(msg, 1);
+			if (!i2c_bus->master_safe_buf)
+				return -ENOMEM;
+			i2c_bus->master_dma_addr =
+				dma_map_single(i2c_bus->dev,
+					       i2c_bus->master_safe_buf, msg->len, DMA_FROM_DEVICE);
+			if (dma_mapping_error(i2c_bus->dev, i2c_bus->master_dma_addr)) {
+				i2c_put_dma_safe_msg_buf(i2c_bus->master_safe_buf, msg, false);
+				i2c_bus->master_safe_buf = NULL;
+				return -ENOMEM;
+			}
+			writel(i2c_bus->master_dma_addr, i2c_bus->reg_base + AST2600_I2CM_RX_DMA);
+		} else if (i2c_bus->mode == BUFF_MODE) {
+			/* buff mode */
+			cmd |= AST2600_I2CM_RX_BUFF_EN;
+			if (msg->flags & I2C_M_RECV_LEN) {
+				dev_dbg(i2c_bus->dev, "smbus read\n");
+				xfer_len = 1;
+			} else {
+				if (msg->len > i2c_bus->buf_size) {
+					xfer_len = i2c_bus->buf_size;
+				} else {
+					xfer_len = msg->len;
+					if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+						cmd |= MASTER_TRIGGER_LAST_STOP;
+				}
+			}
+			writel(AST2600_I2CC_SET_RX_BUF_LEN(xfer_len),
+			       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		} else {
+			/* byte mode */
+			xfer_len = 1;
+			if (msg->flags & I2C_M_RECV_LEN) {
+				dev_dbg(i2c_bus->dev, "smbus read\n");
+			} else {
+				if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count) {
+					if (msg->len == 1)
+						cmd |= MASTER_TRIGGER_LAST_STOP;
+				}
+			}
+		}
+	} else {
+		if (i2c_bus->mode == DMA_MODE) {
+			/* dma mode */
+			if (msg->len > AST2600_I2C_DMA_SIZE) {
+				xfer_len = AST2600_I2C_DMA_SIZE;
+			} else {
+				if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+					cmd |= AST2600_I2CM_STOP_CMD;
+				xfer_len = msg->len;
+			}
+
+			if (xfer_len) {
+				cmd |= AST2600_I2CM_TX_DMA_EN | AST2600_I2CM_TX_CMD;
+				writel(AST2600_I2CM_SET_TX_DMA_LEN(xfer_len - 1),
+				       i2c_bus->reg_base + AST2600_I2CM_DMA_LEN);
+				i2c_bus->master_safe_buf = i2c_get_dma_safe_msg_buf(msg, 1);
+				if (!i2c_bus->master_safe_buf)
+					return -ENOMEM;
+				i2c_bus->master_dma_addr =
+					dma_map_single(i2c_bus->dev, i2c_bus->master_safe_buf,
+						       msg->len, DMA_TO_DEVICE);
+				if (dma_mapping_error(i2c_bus->dev, i2c_bus->master_dma_addr)) {
+					i2c_put_dma_safe_msg_buf(i2c_bus->master_safe_buf,
+								 msg, false);
+					i2c_bus->master_safe_buf = NULL;
+					return -ENOMEM;
+				}
+				writel(i2c_bus->master_dma_addr,
+				       i2c_bus->reg_base + AST2600_I2CM_TX_DMA);
+			}
+		} else if (i2c_bus->mode == BUFF_MODE) {
+			u8 wbuf[4];
+			/* buff mode */
+			if (msg->len > i2c_bus->buf_size) {
+				xfer_len = i2c_bus->buf_size;
+			} else {
+				if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+					cmd |= AST2600_I2CM_STOP_CMD;
+				xfer_len = msg->len;
+			}
+			if (xfer_len) {
+				cmd |= AST2600_I2CM_TX_BUFF_EN | AST2600_I2CM_TX_CMD;
+				if (readl(i2c_bus->reg_base + AST2600_I2CS_ISR))
+					return -ENOMEM;
+				writel(AST2600_I2CC_SET_TX_BUF_LEN(xfer_len),
+				       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+				if (readl(i2c_bus->reg_base + AST2600_I2CS_ISR))
+					return -ENOMEM;
+				for (i = 0; i < xfer_len; i++) {
+					wbuf[i % 4] = msg->buf[i];
+					if (i % 4 == 3)
+						writel(*(u32 *)wbuf, i2c_bus->buf_base + i - 3);
+				}
+				if (--i % 4 != 3)
+					writel(*(u32 *)wbuf, i2c_bus->buf_base + i - (i % 4));
+			}
+			if (readl(i2c_bus->reg_base + AST2600_I2CS_ISR))
+				return -ENOMEM;
+		} else {
+			/* byte mode */
+			if (msg->len <= 1 && (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count))
+				cmd |= AST2600_I2CM_STOP_CMD;
+
+			if (msg->len) {
+				cmd |= AST2600_I2CM_TX_CMD;
+				xfer_len = 1;
+				writel(msg->buf[0], i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+			} else {
+				xfer_len = 0;
+			}
+		}
+	}
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+	return 0;
+}
+
+static int ast2600_i2c_is_irq_error(u32 irq_status)
+{
+	if (irq_status & AST2600_I2CM_ARBIT_LOSS)
+		return -EAGAIN;
+	if (irq_status & (AST2600_I2CM_SDA_DL_TO | AST2600_I2CM_SCL_LOW_TO))
+		return -EBUSY;
+	if (irq_status & (AST2600_I2CM_ABNORMAL))
+		return -EPROTO;
+
+	return 0;
+}
+
+static void ast2600_i2c_master_package_irq(struct ast2600_i2c_bus *i2c_bus, u32 sts)
+{
+	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+	u32 cmd = AST2600_I2CM_PKT_EN;
+	int xfer_len;
+	int i;
+
+	sts &= ~AST2600_I2CM_PKT_DONE;
+	writel(AST2600_I2CM_PKT_DONE, i2c_bus->reg_base + AST2600_I2CM_ISR);
+	switch (sts) {
+	case AST2600_I2CM_PKT_ERROR:
+		i2c_bus->cmd_err = -EAGAIN;
+		complete(&i2c_bus->cmd_complete);
+		break;
+	case AST2600_I2CM_PKT_ERROR | AST2600_I2CM_TX_NAK: /* a0 fix for issue */
+		fallthrough;
+	case AST2600_I2CM_PKT_ERROR | AST2600_I2CM_TX_NAK | AST2600_I2CM_NORMAL_STOP:
+		i2c_bus->cmd_err = -ENXIO;
+		complete(&i2c_bus->cmd_complete);
+		break;
+	case AST2600_I2CM_NORMAL_STOP:
+		/* write 0 byte only have stop isr */
+		i2c_bus->msgs_index++;
+		if (i2c_bus->msgs_index < i2c_bus->msgs_count) {
+			if (ast2600_i2c_do_start(i2c_bus)) {
+				i2c_bus->cmd_err = -ENOMEM;
+				complete(&i2c_bus->cmd_complete);
+			}
+		} else {
+			i2c_bus->cmd_err = i2c_bus->msgs_index;
+			complete(&i2c_bus->cmd_complete);
+		}
+		break;
+	case AST2600_I2CM_TX_ACK:
+	case AST2600_I2CM_TX_ACK | AST2600_I2CM_NORMAL_STOP:
+		if (i2c_bus->mode == DMA_MODE)
+			xfer_len = AST2600_I2C_GET_TX_DMA_LEN(readl(i2c_bus->reg_base +
+							  AST2600_I2CM_DMA_LEN_STS));
+		else if (i2c_bus->mode == BUFF_MODE)
+			xfer_len = AST2600_I2CC_GET_TX_BUF_LEN(readl(i2c_bus->reg_base +
+							   AST2600_I2CC_BUFF_CTRL));
+		else
+			xfer_len = 1;
+
+		i2c_bus->master_xfer_cnt += xfer_len;
+
+		if (i2c_bus->master_xfer_cnt == msg->len) {
+			if (i2c_bus->mode == DMA_MODE) {
+				dma_unmap_single(i2c_bus->dev, i2c_bus->master_dma_addr, msg->len,
+						 DMA_TO_DEVICE);
+				i2c_put_dma_safe_msg_buf(i2c_bus->master_safe_buf, msg, true);
+				i2c_bus->master_safe_buf = NULL;
+			}
+			i2c_bus->msgs_index++;
+			if (i2c_bus->msgs_index == i2c_bus->msgs_count) {
+				i2c_bus->cmd_err = i2c_bus->msgs_index;
+				complete(&i2c_bus->cmd_complete);
+			} else {
+				if (ast2600_i2c_do_start(i2c_bus)) {
+					i2c_bus->cmd_err = -ENOMEM;
+					complete(&i2c_bus->cmd_complete);
+				}
+			}
+		} else {
+			/* do next tx */
+			cmd |= AST2600_I2CM_TX_CMD;
+			if (i2c_bus->mode == DMA_MODE) {
+				cmd |= AST2600_I2CM_TX_DMA_EN;
+				xfer_len = msg->len - i2c_bus->master_xfer_cnt;
+				if (xfer_len > AST2600_I2C_DMA_SIZE) {
+					xfer_len = AST2600_I2C_DMA_SIZE;
+				} else {
+					if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+						cmd |= AST2600_I2CM_STOP_CMD;
+				}
+				writel(AST2600_I2CM_SET_TX_DMA_LEN(xfer_len - 1),
+				       i2c_bus->reg_base + AST2600_I2CM_DMA_LEN);
+				writel(i2c_bus->master_dma_addr + i2c_bus->master_xfer_cnt,
+				       i2c_bus->reg_base + AST2600_I2CM_TX_DMA);
+			} else if (i2c_bus->mode == BUFF_MODE) {
+				u8 wbuf[4];
+
+				cmd |= AST2600_I2CM_TX_BUFF_EN;
+				xfer_len = msg->len - i2c_bus->master_xfer_cnt;
+				if (xfer_len > i2c_bus->buf_size) {
+					xfer_len = i2c_bus->buf_size;
+				} else {
+					if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+						cmd |= AST2600_I2CM_STOP_CMD;
+				}
+				for (i = 0; i < xfer_len; i++) {
+					wbuf[i % 4] = msg->buf[i2c_bus->master_xfer_cnt + i];
+					if (i % 4 == 3)
+						writel(*(u32 *)wbuf, i2c_bus->buf_base + i - 3);
+				}
+				if (--i % 4 != 3)
+					writel(*(u32 *)wbuf, i2c_bus->buf_base + i - (i % 4));
+				writel(AST2600_I2CC_SET_TX_BUF_LEN(xfer_len),
+				       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+			} else {
+				/* byte */
+				if ((i2c_bus->msgs_index + 1 == i2c_bus->msgs_count) &&
+				    ((i2c_bus->master_xfer_cnt + 1) == msg->len)) {
+					cmd |= AST2600_I2CM_STOP_CMD;
+				}
+				writel(msg->buf[i2c_bus->master_xfer_cnt],
+				       i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+			}
+			writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+		}
+		break;
+	case AST2600_I2CM_RX_DONE:
+#ifdef CONFIG_I2C_SLAVE
+		/* Workaround for master/slave package mode enable rx done stuck issue
+		 * When master go for first read (RX_DONE), slave mode will also effect
+		 * Then controller will send nack, not operate anymore.
+		 */
+		if (readl(i2c_bus->reg_base + AST2600_I2CS_CMD_STS) & AST2600_I2CS_PKT_MODE_EN) {
+			u32 slave_cmd = readl(i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+
+			writel(0, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+			writel(slave_cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+		}
+		fallthrough;
+#endif
+	case AST2600_I2CM_RX_DONE | AST2600_I2CM_NORMAL_STOP:
+		/* do next rx */
+		if (i2c_bus->mode == DMA_MODE) {
+			xfer_len = AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
+								    AST2600_I2CM_DMA_LEN_STS));
+		} else if (i2c_bus->mode == BUFF_MODE) {
+			xfer_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+								     AST2600_I2CC_BUFF_CTRL));
+			for (i = 0; i < xfer_len; i++)
+				msg->buf[i2c_bus->master_xfer_cnt + i] =
+					readb(i2c_bus->buf_base + 0x10 + i);
+		} else {
+			xfer_len = 1;
+			msg->buf[i2c_bus->master_xfer_cnt] =
+				AST2600_I2CC_GET_RX_BUFF(readl(i2c_bus->reg_base +
+						     AST2600_I2CC_STS_AND_BUFF));
+		}
+
+		if (msg->flags & I2C_M_RECV_LEN) {
+			msg->len = msg->buf[0] + ((msg->flags & I2C_CLIENT_PEC) ? 2 : 1);
+			msg->len = min_t(unsigned int, msg->len, I2C_SMBUS_BLOCK_MAX);
+			msg->flags &= ~I2C_M_RECV_LEN;
+		}
+		i2c_bus->master_xfer_cnt += xfer_len;
+
+		if (i2c_bus->master_xfer_cnt == msg->len) {
+			if (i2c_bus->mode == DMA_MODE) {
+				dma_unmap_single(i2c_bus->dev, i2c_bus->master_dma_addr, msg->len,
+						 DMA_FROM_DEVICE);
+				i2c_put_dma_safe_msg_buf(i2c_bus->master_safe_buf, msg, true);
+				i2c_bus->master_safe_buf = NULL;
+			}
+
+			i2c_bus->msgs_index++;
+			if (i2c_bus->msgs_index == i2c_bus->msgs_count) {
+				i2c_bus->cmd_err = i2c_bus->msgs_index;
+				complete(&i2c_bus->cmd_complete);
+			} else {
+				if (ast2600_i2c_do_start(i2c_bus)) {
+					i2c_bus->cmd_err = -ENOMEM;
+					complete(&i2c_bus->cmd_complete);
+				}
+			}
+		} else {
+			/* next rx */
+			cmd |= AST2600_I2CM_RX_CMD;
+			if (i2c_bus->mode == DMA_MODE) {
+				cmd |= AST2600_I2CM_RX_DMA_EN;
+				xfer_len = msg->len - i2c_bus->master_xfer_cnt;
+				if (xfer_len > AST2600_I2C_DMA_SIZE) {
+					xfer_len = AST2600_I2C_DMA_SIZE;
+				} else {
+					if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+						cmd |= MASTER_TRIGGER_LAST_STOP;
+				}
+				writel(AST2600_I2CM_SET_RX_DMA_LEN(xfer_len - 1),
+				       i2c_bus->reg_base + AST2600_I2CM_DMA_LEN);
+				writel(i2c_bus->master_dma_addr + i2c_bus->master_xfer_cnt,
+				       i2c_bus->reg_base + AST2600_I2CM_RX_DMA);
+			} else if (i2c_bus->mode == BUFF_MODE) {
+				cmd |= AST2600_I2CM_RX_BUFF_EN;
+				xfer_len = msg->len - i2c_bus->master_xfer_cnt;
+				if (xfer_len > i2c_bus->buf_size) {
+					xfer_len = i2c_bus->buf_size;
+				} else {
+					if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+						cmd |= MASTER_TRIGGER_LAST_STOP;
+				}
+				writel(AST2600_I2CC_SET_RX_BUF_LEN(xfer_len),
+				       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+			} else {
+				if ((i2c_bus->msgs_index + 1 == i2c_bus->msgs_count) &&
+				    ((i2c_bus->master_xfer_cnt + 1) == msg->len)) {
+					cmd |= MASTER_TRIGGER_LAST_STOP;
+				}
+			}
+			writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+		}
+		break;
+	default:
+		dev_dbg(i2c_bus->dev, "unhandled sts %x\n", sts);
+		break;
+	}
+}
+
+static int ast2600_i2c_master_irq(struct ast2600_i2c_bus *i2c_bus)
+{
+	u32 sts = readl(i2c_bus->reg_base + AST2600_I2CM_ISR);
+	u32 ier = readl(i2c_bus->reg_base + AST2600_I2CM_IER);
+	u32 ctrl = 0;
+
+	if (!i2c_bus->alert_enable)
+		sts &= ~AST2600_I2CM_SMBUS_ALT;
+
+	if (AST2600_I2CM_BUS_RECOVER_FAIL & sts) {
+		writel(AST2600_I2CM_BUS_RECOVER_FAIL, i2c_bus->reg_base + AST2600_I2CM_ISR);
+		ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+		writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+		writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+		i2c_bus->cmd_err = -EPROTO;
+		complete(&i2c_bus->cmd_complete);
+		return 1;
+	}
+
+	if (AST2600_I2CM_BUS_RECOVER & sts) {
+		writel(AST2600_I2CM_BUS_RECOVER, i2c_bus->reg_base + AST2600_I2CM_ISR);
+		i2c_bus->cmd_err = 0;
+		complete(&i2c_bus->cmd_complete);
+		return 1;
+	}
+
+	if (AST2600_I2CM_SMBUS_ALT & sts) {
+		if (ier & AST2600_I2CM_SMBUS_ALT) {
+			/* Disable ALT INT */
+			writel(ier & ~AST2600_I2CM_SMBUS_ALT, i2c_bus->reg_base + AST2600_I2CM_IER);
+			i2c_handle_smbus_alert(i2c_bus->ara);
+			writel(AST2600_I2CM_SMBUS_ALT, i2c_bus->reg_base + AST2600_I2CM_ISR);
+			dev_err(i2c_bus->dev,
+				"ast2600_master_alert_recv bus id %d, Disable Alt, Please Imple\n",
+				i2c_bus->adap.nr);
+			return 1;
+		}
+	}
+
+	i2c_bus->cmd_err = ast2600_i2c_is_irq_error(sts);
+	if (i2c_bus->cmd_err) {
+		writel(AST2600_I2CM_PKT_DONE, i2c_bus->reg_base + AST2600_I2CM_ISR);
+		complete(&i2c_bus->cmd_complete);
+		return 1;
+	}
+
+	if (AST2600_I2CM_PKT_DONE & sts) {
+		ast2600_i2c_master_package_irq(i2c_bus, sts);
+		return 1;
+	}
+
+	return 0;
+}
+
+static irqreturn_t ast2600_i2c_bus_irq(int irq, void *dev_id)
+{
+	struct ast2600_i2c_bus *i2c_bus = dev_id;
+
+#ifdef CONFIG_I2C_SLAVE
+	if (readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL) & AST2600_I2CC_SLAVE_EN) {
+		if (ast2600_i2c_slave_irq(i2c_bus))
+			return IRQ_HANDLED;
+	}
+#endif
+	return ast2600_i2c_master_irq(i2c_bus) ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static int ast2600_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+	struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(adap);
+	unsigned long timeout;
+	int ret;
+
+	/* If bus is busy in a single master environment, attempt recovery. */
+	if (!i2c_bus->multi_master &&
+	    (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) & AST2600_I2CC_BUS_BUSY_STS)) {
+		ret = ast2600_i2c_recover_bus(i2c_bus);
+		if (ret)
+			return ret;
+	}
+
+#ifdef CONFIG_I2C_SLAVE
+	if (i2c_bus->mode == BUFF_MODE) {
+		if (i2c_bus->slave_operate)
+			return -EBUSY;
+		/* disable slave isr */
+		writel(0, i2c_bus->reg_base + AST2600_I2CS_IER);
+		if (readl(i2c_bus->reg_base + AST2600_I2CS_ISR) || i2c_bus->slave_operate) {
+			writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_IER);
+			return -EBUSY;
+		}
+	}
+#endif
+
+	i2c_bus->cmd_err = 0;
+	i2c_bus->msgs = msgs;
+	i2c_bus->msgs_index = 0;
+	i2c_bus->msgs_count = num;
+	reinit_completion(&i2c_bus->cmd_complete);
+	ret = ast2600_i2c_do_start(i2c_bus);
+#ifdef CONFIG_I2C_SLAVE
+	/* avoid race condication slave is wait and master wait 1st slave operate */
+	if (i2c_bus->mode == BUFF_MODE)
+		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_IER);
+#endif
+	if (ret)
+		goto master_out;
+	timeout = wait_for_completion_timeout(&i2c_bus->cmd_complete, i2c_bus->adap.timeout);
+	if (timeout == 0) {
+		u32 isr = readl(i2c_bus->reg_base + AST2600_I2CM_ISR);
+		u32 i2c_status = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+
+		dev_dbg(i2c_bus->dev, "timeout isr[%x], sts[%x]\n", isr, i2c_status);
+		if (isr || (i2c_status & AST2600_I2CC_TX_DIR_MASK)) {
+			u32 ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+			writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+			writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+#ifdef CONFIG_I2C_SLAVE
+			if (ctrl & AST2600_I2CC_SLAVE_EN) {
+				u32 cmd = SLAVE_TRIGGER_CMD;
+
+				if (i2c_bus->mode == DMA_MODE) {
+					cmd |= AST2600_I2CS_RX_DMA_EN;
+					writel(i2c_bus->slave_dma_addr,
+					       i2c_bus->reg_base + AST2600_I2CS_RX_DMA);
+					writel(i2c_bus->slave_dma_addr,
+					       i2c_bus->reg_base + AST2600_I2CS_TX_DMA);
+					writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
+					       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+				} else if (i2c_bus->mode == BUFF_MODE) {
+					cmd = SLAVE_TRIGGER_CMD;
+				} else {
+					cmd &= ~AST2600_I2CS_PKT_MODE_EN;
+				}
+				writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+			}
+#endif
+		}
+		ret = -ETIMEDOUT;
+	} else {
+		ret = i2c_bus->cmd_err;
+	}
+
+	dev_dbg(i2c_bus->dev, "bus%d-m: %d end\n", i2c_bus->adap.nr, i2c_bus->cmd_err);
+
+master_out:
+	if (i2c_bus->mode == DMA_MODE) {
+		kfree(i2c_bus->master_safe_buf);
+	    i2c_bus->master_safe_buf = NULL;
+	}
+
+	return ret;
+}
+
+static void ast2600_i2c_init(struct ast2600_i2c_bus *i2c_bus)
+{
+	struct platform_device *pdev = to_platform_device(i2c_bus->dev);
+	u32 fun_ctrl = AST2600_I2CC_BUS_AUTO_RELEASE | AST2600_I2CC_MASTER_EN;
+
+	/* I2C Reset */
+	writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+	if (of_property_read_bool(pdev->dev.of_node, "multi-master"))
+		i2c_bus->multi_master = true;
+	else
+		fun_ctrl |= AST2600_I2CC_MULTI_MASTER_DIS;
+
+	/* Enable Master Mode */
+	writel(fun_ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+	/* disable slave address */
+	writel(0, i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
+
+	/* Set AC Timing */
+	writel(ast2600_select_i2c_clock(i2c_bus), i2c_bus->reg_base + AST2600_I2CC_AC_TIMING);
+
+	/* Clear Interrupt */
+	writel(0xfffffff, i2c_bus->reg_base + AST2600_I2CM_ISR);
+
+#ifdef CONFIG_I2C_SLAVE
+	/* for memory buffer initial */
+	if (i2c_bus->mode == DMA_MODE) {
+		i2c_bus->slave_dma_buf =
+			dmam_alloc_coherent(i2c_bus->dev, I2C_SLAVE_MSG_BUF_SIZE,
+					    &i2c_bus->slave_dma_addr, GFP_KERNEL);
+		if (!i2c_bus->slave_dma_buf)
+			return;
+	}
+
+	writel(0xfffffff, i2c_bus->reg_base + AST2600_I2CS_ISR);
+
+	if (i2c_bus->mode == BYTE_MODE) {
+		writel(0xffff, i2c_bus->reg_base + AST2600_I2CS_IER);
+	} else {
+		/* Set interrupt generation of I2C slave controller */
+		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_IER);
+	}
+#endif
+}
+
+#ifdef CONFIG_I2C_SLAVE
+static int ast2600_i2c_reg_slave(struct i2c_client *client)
+{
+	struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(client->adapter);
+	u32 cmd = SLAVE_TRIGGER_CMD;
+
+	if (i2c_bus->slave)
+		return -EINVAL;
+
+	dev_dbg(i2c_bus->dev, "slave addr %x\n", client->addr);
+
+	writel(0, i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
+	writel(AST2600_I2CC_SLAVE_EN | readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL),
+	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+	/* trigger rx buffer */
+	if (i2c_bus->mode == DMA_MODE) {
+		cmd |= AST2600_I2CS_RX_DMA_EN;
+		writel(i2c_bus->slave_dma_addr, i2c_bus->reg_base + AST2600_I2CS_RX_DMA);
+		writel(i2c_bus->slave_dma_addr, i2c_bus->reg_base + AST2600_I2CS_TX_DMA);
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+	} else if (i2c_bus->mode == BUFF_MODE) {
+		cmd = SLAVE_TRIGGER_CMD;
+	} else {
+		cmd &= ~AST2600_I2CS_PKT_MODE_EN;
+	}
+
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+	i2c_bus->slave = client;
+	/* Set slave addr. */
+	writel(client->addr | AST2600_I2CS_ADDR1_ENABLE,
+	       i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
+
+	return 0;
+}
+
+static int ast2600_i2c_unreg_slave(struct i2c_client *slave)
+{
+	struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(slave->adapter);
+
+	WARN_ON(!i2c_bus->slave);
+
+	/* Turn off slave mode. */
+	writel(~AST2600_I2CC_SLAVE_EN & readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL),
+	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+	writel(readl(i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL) & ~AST2600_I2CS_ADDR1_MASK,
+	       i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
+
+	i2c_bus->slave = NULL;
+
+	return 0;
+}
+#endif
+
+static u32 ast2600_i2c_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA;
+}
+
+static const struct i2c_algorithm i2c_ast2600_algorithm = {
+	.master_xfer = ast2600_i2c_master_xfer,
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+	.reg_slave = ast2600_i2c_reg_slave,
+	.unreg_slave = ast2600_i2c_unreg_slave,
+#endif
+	.functionality = ast2600_i2c_functionality,
+};
+
+static const struct of_device_id ast2600_i2c_bus_of_table[] = {
+	{
+		.compatible = "aspeed,ast2600-i2cv2",
+	},
+	{}
+};
+
+MODULE_DEVICE_TABLE(of, ast2600_i2c_bus_of_table);
+
+static int ast2600_i2c_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	struct ast2600_i2c_bus *i2c_bus;
+	struct resource *res;
+	u32 global_ctrl;
+	int ret = 0;
+
+	i2c_bus = devm_kzalloc(dev, sizeof(*i2c_bus), GFP_KERNEL);
+	if (!i2c_bus)
+		return dev_err_probe(dev, -ENOMEM, "no memory allocated\n");
+
+	i2c_bus->reg_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(i2c_bus->reg_base))
+		return PTR_ERR(i2c_bus->reg_base);
+
+	i2c_bus->rst = devm_reset_control_get_shared(dev, NULL);
+	if (IS_ERR(i2c_bus->rst))
+		return dev_err_probe(dev, PTR_ERR(i2c_bus->rst), "Missing reset ctrl\n");
+
+	reset_control_deassert(i2c_bus->rst);
+
+	i2c_bus->global_regs = syscon_regmap_lookup_by_phandle(np, "aspeed,global-regs");
+	if (IS_ERR(i2c_bus->global_regs))
+		return PTR_ERR(i2c_bus->global_regs);
+
+	regmap_read(i2c_bus->global_regs, AST2600_I2CG_CTRL, &global_ctrl);
+	if ((global_ctrl & AST2600_GLOBAL_INIT) != AST2600_GLOBAL_INIT) {
+		regmap_write(i2c_bus->global_regs, AST2600_I2CG_CTRL, AST2600_GLOBAL_INIT);
+		regmap_write(i2c_bus->global_regs, AST2600_I2CG_CLK_DIV_CTRL, I2CCG_DIV_CTRL);
+	}
+
+	i2c_bus->slave_operate = 0;
+	i2c_bus->dev = dev;
+	i2c_bus->mode = BUFF_MODE;
+
+	if (of_property_read_bool(pdev->dev.of_node, "aspeed,enable-dma"))
+		i2c_bus->mode = DMA_MODE;
+
+	if (i2c_bus->mode == BUFF_MODE) {
+		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+		if (res && resource_size(res) >= 2) {
+			i2c_bus->buf_base = devm_ioremap_resource(dev, res);
+
+			if (!IS_ERR_OR_NULL(i2c_bus->buf_base))
+				i2c_bus->buf_size = resource_size(res) / 2;
+		} else {
+			i2c_bus->mode = BYTE_MODE;
+		}
+	}
+
+	/* i2c timeout counter: use base clk4 1Mhz,
+	 * per unit: 1/(1000/4096) = 4096us
+	 */
+	ret = of_property_read_u32(dev->of_node,
+				   "i2c-scl-clk-low-timeout-us",
+				   &i2c_bus->timeout);
+	if (!ret)
+		i2c_bus->timeout /= 4096;
+
+	init_completion(&i2c_bus->cmd_complete);
+
+	i2c_bus->irq = platform_get_irq(pdev, 0);
+	if (i2c_bus->irq < 0)
+		return i2c_bus->irq;
+
+	platform_set_drvdata(pdev, i2c_bus);
+
+	i2c_bus->clk = devm_clk_get(i2c_bus->dev, NULL);
+	if (IS_ERR(i2c_bus->clk))
+		return dev_err_probe(i2c_bus->dev, PTR_ERR(i2c_bus->clk), "Can't get clock\n");
+
+	i2c_bus->apb_clk = clk_get_rate(i2c_bus->clk);
+
+	ret = of_property_read_u32(dev->of_node, "clock-frequency", &i2c_bus->bus_frequency);
+	if (ret < 0) {
+		dev_warn(dev, "Could not read clock-frequency property\n");
+		i2c_bus->bus_frequency = 100000;
+	}
+
+	/* Initialize the I2C adapter */
+	i2c_bus->adap.owner = THIS_MODULE;
+	i2c_bus->adap.algo = &i2c_ast2600_algorithm;
+	i2c_bus->adap.retries = 0;
+	i2c_bus->adap.dev.parent = i2c_bus->dev;
+	i2c_bus->adap.dev.of_node = dev->of_node;
+	i2c_bus->adap.algo_data = i2c_bus;
+	strscpy(i2c_bus->adap.name, pdev->name, sizeof(i2c_bus->adap.name));
+	i2c_set_adapdata(&i2c_bus->adap, i2c_bus);
+
+	ast2600_i2c_init(i2c_bus);
+
+	ret = devm_request_irq(dev, i2c_bus->irq, ast2600_i2c_bus_irq, 0,
+			       dev_name(dev), i2c_bus);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "Unable to request irq %d\n", i2c_bus->irq);
+
+	if (of_property_read_bool(dev->of_node, "smbus-alert")) {
+		i2c_bus->alert_enable = true;
+		i2c_bus->ara = i2c_new_smbus_alert_device(&i2c_bus->adap, &i2c_bus->alert_data);
+		if (!i2c_bus->ara)
+			dev_warn(dev, "Failed to register ARA client\n");
+
+		writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER | AST2600_I2CM_SMBUS_ALT,
+		       i2c_bus->reg_base + AST2600_I2CM_IER);
+	} else {
+		i2c_bus->alert_enable = false;
+		/* Set interrupt generation of I2C master controller */
+		writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER,
+		       i2c_bus->reg_base + AST2600_I2CM_IER);
+	}
+
+	ret = devm_i2c_add_adapter(dev, &i2c_bus->adap);
+	if (ret)
+		return ret;
+
+	dev_info(dev, "%s [%d]: adapter [%d khz] mode [%d]\n",
+		 dev->of_node->name, i2c_bus->adap.nr, i2c_bus->bus_frequency / 1000,
+		 i2c_bus->mode);
+
+	return 0;
+}
+
+static int ast2600_i2c_remove(struct platform_device *pdev)
+{
+	struct ast2600_i2c_bus *i2c_bus = platform_get_drvdata(pdev);
+
+	/* Disable everything. */
+	writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+	writel(0, i2c_bus->reg_base + AST2600_I2CM_IER);
+
+	i2c_del_adapter(&i2c_bus->adap);
+	devm_free_irq(&pdev->dev, i2c_bus->irq, i2c_bus);
+
+#ifdef CONFIG_I2C_SLAVE
+	/* for memory buffer initial */
+	if (i2c_bus->mode == DMA_MODE)
+		dmam_free_coherent(i2c_bus->dev, I2C_SLAVE_MSG_BUF_SIZE,
+				   i2c_bus->slave_dma_buf, i2c_bus->slave_dma_addr);
+#endif
+
+	return 0;
+}
+
+static struct platform_driver ast2600_i2c_bus_driver = {
+	.probe = ast2600_i2c_probe,
+	.remove = ast2600_i2c_remove,
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.of_match_table = ast2600_i2c_bus_of_table,
+	},
+};
+module_platform_driver(ast2600_i2c_bus_driver);
+
+MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>");
+MODULE_DESCRIPTION("ASPEED AST2600 I2C Controller Driver");
+MODULE_LICENSE("GPL");