[0/4] Add GPIO support for RDA8810PL SoC

Hello,

This patchset adds GPIO controller support for RDA Micro RDA8810PL
SoC. This SoC has 4 GPIO controllers and each handles 32 GPIOs. Except
GPIOC, all controllers are capable of generating edge/level interrupts
from first 8 GPIO lines. The pinctrl part for this SoC will be added
later.

This driver has been validated on 96Boards OrangePi i96 board from
Shenzhen Xunlong Software Co.,Limited with libgpiod.

Thanks,
Mani

Manivannan Sadhasivam (4):
  dt-bindings: gpio: Add devicetree binding for RDA Micro GPIO
    controller
  gpio: Add RDA Micro GPIO controller support
  ARM: dts: Add RDA8810PL GPIO controllers
  MAINTAINERS: Add entry for RDA Micro GPIO driver and binding

 .../devicetree/bindings/gpio/gpio-rda.yaml    |  50 +++
 MAINTAINERS                                   |   2 +
 arch/arm/boot/dts/rda8810pl.dtsi              |  48 +++
 drivers/gpio/Kconfig                          |   8 +
 drivers/gpio/Makefile                         |   1 +
 drivers/gpio/gpio-rda.c                       | 334 ++++++++++++++++++
 6 files changed, 443 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpio/gpio-rda.yaml
 create mode 100644 drivers/gpio/gpio-rda.c

-- 
2.17.1

Hi Bartosz,

Thanks for the quick review! Please find the reply inline.

On Mon, Oct 14, 2019 at 04:25:29PM +0200, Bartosz Golaszewski wrote:
> niedz., 13 paź 2019 o 13:40 Manivannan Sadhasivam

> <manivannan.sadhasivam@linaro.org> napisał(a):

> >

> > Add support for GPIO controller from RDA Micro.

> 

> Looks nice and clean, just a couple nits.

> 

> >

> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

> > ---

> >  drivers/gpio/Kconfig    |   8 +

> >  drivers/gpio/Makefile   |   1 +

> >  drivers/gpio/gpio-rda.c | 334 ++++++++++++++++++++++++++++++++++++++++

> >  3 files changed, 343 insertions(+)

> >  create mode 100644 drivers/gpio/gpio-rda.c

> >

> > diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig

> > index 38e096e6925f..71826e61fdb3 100644

> > --- a/drivers/gpio/Kconfig

> > +++ b/drivers/gpio/Kconfig

> > @@ -435,6 +435,14 @@ config GPIO_RCAR

> >         help

> >           Say yes here to support GPIO on Renesas R-Car SoCs.

> >

> > +config GPIO_RDA

> > +       bool "RDA Micro GPIO controller support"

> > +       depends on ARCH_RDA || COMPILE_TEST

> > +       depends on OF_GPIO

> > +       select GPIOLIB_IRQCHIP

> > +       help

> > +         Say Y here to support RDA Micro GPIO controller.

> > +

> >  config GPIO_REG

> >         bool

> >         help

> > diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile

> > index d2fd19c15bae..5c68c9a48fa3 100644

> > --- a/drivers/gpio/Makefile

> > +++ b/drivers/gpio/Makefile

> > @@ -115,6 +115,7 @@ obj-$(CONFIG_GPIO_PXA)                      += gpio-pxa.o

> >  obj-$(CONFIG_GPIO_RASPBERRYPI_EXP)     += gpio-raspberrypi-exp.o

> >  obj-$(CONFIG_GPIO_RC5T583)             += gpio-rc5t583.o

> >  obj-$(CONFIG_GPIO_RCAR)                        += gpio-rcar.o

> > +obj-$(CONFIG_GPIO_RDA)                 += gpio-rda.o

> >  obj-$(CONFIG_GPIO_RDC321X)             += gpio-rdc321x.o

> >  obj-$(CONFIG_GPIO_REG)                 += gpio-reg.o

> >  obj-$(CONFIG_ARCH_SA1100)              += gpio-sa1100.o

> > diff --git a/drivers/gpio/gpio-rda.c b/drivers/gpio/gpio-rda.c

> > new file mode 100644

> > index 000000000000..5a4adeb25f72

> > --- /dev/null

> > +++ b/drivers/gpio/gpio-rda.c

> > @@ -0,0 +1,334 @@

> > +// SPDX-License-Identifier: GPL-2.0-only

> > +/*

> > + * RDA Micro GPIO driver

> > + *

> > + * Copyright (C) 2012 RDA Micro Inc.

> > + * Copyright (C) 2019 Manivannan Sadhasivam

> > + */

> > +

> > +#include <linux/bitops.h>

> > +#include <linux/gpio/driver.h>

> > +#include <linux/kernel.h>

> > +#include <linux/module.h>

> > +#include <linux/of_device.h>

> > +#include <linux/platform_device.h>

> > +#include <linux/spinlock.h>

> > +

> > +#define RDA_GPIO_OEN_VAL               0x00

> > +#define RDA_GPIO_OEN_SET_OUT           0x04

> > +#define RDA_GPIO_OEN_SET_IN            0x08

> > +#define RDA_GPIO_VAL                   0x0c

> > +#define RDA_GPIO_SET                   0x10

> > +#define RDA_GPIO_CLR                   0x14

> > +#define RDA_GPIO_INT_CTRL_SET          0x18

> > +#define RDA_GPIO_INT_CTRL_CLR          0x1c

> > +#define RDA_GPIO_INT_CLR               0x20

> > +#define RDA_GPIO_INT_STATUS            0x24

> > +

> > +#define RDA_GPIO_IRQ_RISE_SHIFT                0

> > +#define RDA_GPIO_IRQ_FALL_SHIFT                8

> > +#define RDA_GPIO_DEBOUCE_SHIFT         16

> > +#define RDA_GPIO_LEVEL_SHIFT           24

> > +

> > +#define RDA_GPIO_IRQ_MASK              0xff

> > +

> > +/* Each bank consists of 32 GPIOs */

> > +#define RDA_GPIO_BANK_NR       32

> > +

> > +struct rda_gpio {

> > +       struct gpio_chip chip;

> > +       void __iomem *base;

> > +       spinlock_t lock;

> > +       struct irq_chip irq_chip;

> > +       int irq;

> > +};

> > +

> > +static void rda_gpio_update(struct gpio_chip *chip, unsigned int offset,

> > +                           u16 reg, int val)

> > +{

> > +       struct rda_gpio *rda_gpio = gpiochip_get_data(chip);

> > +       void __iomem *base = rda_gpio->base;

> > +       unsigned long flags;

> > +       u32 tmp;

> > +

> > +       spin_lock_irqsave(&rda_gpio->lock, flags);

> > +       tmp = readl_relaxed(base + reg);

> > +

> > +       if (val)

> > +               tmp |= BIT(offset);

> > +       else

> > +               tmp &= ~BIT(offset);

> > +

> > +       writel_relaxed(tmp, base + reg);

> > +       spin_unlock_irqrestore(&rda_gpio->lock, flags);

> > +}

> 

> If you used the mmio regmap, you could save all this code and reuse

> regmap's update helpers. This is just a suggestion, not a requirement

> though.

> 


Agree. I'll post a patch later once this driver gets in.

> > +

> > +static int rda_gpio_request(struct gpio_chip *chip, unsigned int offset)

> > +{

> > +       /* Not supported currently */

> > +       return 0;

> > +}

> > +

> > +static void rda_gpio_free(struct gpio_chip *chip, unsigned int offset)

> > +{

> > +       /* Not supported currently */

> > +}

> 

> Just don't implement these callbacks if they're doing nothing.

> 


Hmm. Since these are some critical callbacks, I thought the drivers should
explicitly expose even not implemented. But I can remove them.

> > +

> > +static int rda_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)

> > +{

> > +       rda_gpio_update(chip, offset, RDA_GPIO_OEN_SET_IN, 1);

> > +

> > +       return 0;

> > +}

> > +

> > +static int rda_gpio_direction_output(struct gpio_chip *chip,

> > +                                    unsigned int offset, int value)

> > +{

> > +       rda_gpio_update(chip, offset, RDA_GPIO_OEN_SET_OUT, 1);

> > +

> > +       return 0;

> > +}

> > +

> > +static int rda_gpio_get(struct gpio_chip *chip, unsigned int offset)

> > +{

> > +       struct rda_gpio *rda_gpio = gpiochip_get_data(chip);

> > +       void __iomem *base = rda_gpio->base;

> > +

> > +       if (readl_relaxed(base + RDA_GPIO_OEN_VAL) & BIT(offset))

> > +               return !!(readl_relaxed(base + RDA_GPIO_VAL) & BIT(offset));

> > +       else

> > +               return !!(readl_relaxed(base + RDA_GPIO_SET) & BIT(offset));

> > +}

> > +

> > +static void rda_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)

> > +{

> > +       if (value)

> > +               rda_gpio_update(chip, offset, RDA_GPIO_SET, 1);

> > +       else

> > +               rda_gpio_update(chip, offset, RDA_GPIO_CLR, 1);

> > +}

> > +

> > +static void rda_gpio_irq_mask(struct irq_data *data)

> > +{

> > +       struct gpio_chip *chip = irq_data_get_irq_chip_data(data);

> > +       struct rda_gpio *rda_gpio = gpiochip_get_data(chip);

> > +       void __iomem *base = rda_gpio->base;

> > +       u32 offset = irqd_to_hwirq(data);

> > +       u32 value;

> > +

> > +       value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;

> > +       value |= BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;

> > +

> > +       writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);

> > +}

> > +

> > +static void rda_gpio_irq_ack(struct irq_data *data)

> > +{

> > +       struct gpio_chip *chip = irq_data_get_irq_chip_data(data);

> > +       u32 offset = irqd_to_hwirq(data);

> > +

> > +       rda_gpio_update(chip, offset, RDA_GPIO_INT_CLR, 1);

> > +}

> > +

> > +static int rda_gpio_set_irq(struct gpio_chip *chip, u32 offset,

> > +                           unsigned int flow_type)

> > +{

> > +       struct rda_gpio *rda_gpio = gpiochip_get_data(chip);

> > +       void __iomem *base = rda_gpio->base;

> > +       u32 value;

> > +

> > +       switch (flow_type) {

> > +       case IRQ_TYPE_EDGE_RISING:

> > +               /* Set rising edge trigger */

> > +               value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;

> > +               writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);

> > +

> > +               /* Switch to edge trigger interrupt */

> > +               value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT;

> > +               writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);

> > +               break;

> > +

> > +       case IRQ_TYPE_EDGE_FALLING:

> > +               /* Set falling edge trigger */

> > +               value = BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;

> > +               writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);

> > +

> > +               /* Switch to edge trigger interrupt */

> > +               value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT;

> > +               writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);

> > +               break;

> > +

> > +       case IRQ_TYPE_EDGE_BOTH:

> > +               /* Set both edge trigger */

> > +               value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;

> > +               value |= BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;

> > +               writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);

> > +

> > +               /* Switch to edge trigger interrupt */

> > +               value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT;

> > +               writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);

> > +               break;

> > +

> > +       case IRQ_TYPE_LEVEL_HIGH:

> > +               /* Set high level trigger */

> > +               value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;

> > +

> > +               /* Switch to level trigger interrupt */

> > +               value |= BIT(offset) << RDA_GPIO_LEVEL_SHIFT;

> > +               writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);

> > +               break;

> > +

> > +       case IRQ_TYPE_LEVEL_LOW:

> > +               /* Set low level trigger */

> > +               value = BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;

> > +

> > +               /* Switch to level trigger interrupt */

> > +               value |= BIT(offset) << RDA_GPIO_LEVEL_SHIFT;

> > +               writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);

> > +               break;

> > +

> > +       default:

> > +               return -EINVAL;

> > +       }

> > +

> > +       return 0;

> > +}

> > +

> > +static void rda_gpio_irq_unmask(struct irq_data *data)

> > +{

> > +       struct gpio_chip *chip = irq_data_get_irq_chip_data(data);

> > +       u32 offset = irqd_to_hwirq(data);

> > +       u32 trigger = irqd_get_trigger_type(data);

> > +

> > +       rda_gpio_set_irq(chip, offset, trigger);

> > +}

> > +

> > +static int rda_gpio_irq_set_type(struct irq_data *data, unsigned int flow_type)

> > +{

> > +       struct gpio_chip *chip = irq_data_get_irq_chip_data(data);

> > +       u32 offset = irqd_to_hwirq(data);

> > +       int ret;

> > +

> > +       ret = rda_gpio_set_irq(chip, offset, flow_type);

> > +       if (ret)

> > +               return ret;

> > +

> > +       if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))

> > +               irq_set_handler_locked(data, handle_level_irq);

> > +       else if (flow_type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))

> > +               irq_set_handler_locked(data, handle_edge_irq);

> > +

> > +       return 0;

> > +}

> > +

> > +static void rda_gpio_irq_handler(struct irq_desc *desc)

> > +{

> > +       struct gpio_chip *chip = irq_desc_get_handler_data(desc);

> > +       struct irq_chip *ic = irq_desc_get_chip(desc);

> > +       struct rda_gpio *rda_gpio = gpiochip_get_data(chip);

> > +       unsigned long status;

> > +       u32 n, girq;

> > +

> > +       chained_irq_enter(ic, desc);

> > +

> > +       status = readl_relaxed(rda_gpio->base + RDA_GPIO_INT_STATUS);

> > +       /* Only lower 8 bits are capable of generating interrupts */

> > +       status &= RDA_GPIO_IRQ_MASK;

> > +

> > +       for_each_set_bit(n, &status, RDA_GPIO_BANK_NR) {

> > +               girq = irq_find_mapping(chip->irq.domain, n);

> > +               generic_handle_irq(girq);

> > +       }

> > +

> > +       chained_irq_exit(ic, desc);

> > +}

> > +

> > +static int rda_gpio_probe(struct platform_device *pdev)

> > +{

> > +       struct device_node *np = pdev->dev.of_node;

> > +       struct gpio_irq_chip *irq;

> 

> Can you call this variable irq_chip? Visually it interferes with

> rda_gpio->irq too much.

> 


okay.

> > +       struct rda_gpio *rda_gpio;

> > +       u32 ngpios;

> > +       int ret;

> > +

> > +       rda_gpio = devm_kzalloc(&pdev->dev, sizeof(*rda_gpio), GFP_KERNEL);

> > +       if (!rda_gpio)

> > +               return -ENOMEM;

> > +

> > +       ret = of_property_read_u32(np, "ngpios", &ngpios);

> > +       if (ret < 0)

> > +               return ret;

> > +

> 

> Please use the generic device property helpers unless it's really

> necessary to use of_ variants. Also: remove the of_device.h include.

> 


okay.

> > +       /*

> > +        * Not all ports have interrupt capability. For instance, on

> > +        * RDA8810PL, GPIOC doesn't support interrupt. So we must handle

> > +        * those also.

> > +        */

> > +       rda_gpio->irq = platform_get_irq(pdev, 0);

> > +

> > +       rda_gpio->base = devm_platform_ioremap_resource(pdev, 0);

> > +       if (IS_ERR(rda_gpio->base))

> > +               return PTR_ERR(rda_gpio->base);

> > +

> > +       spin_lock_init(&rda_gpio->lock);

> > +

> > +       rda_gpio->chip.label = dev_name(&pdev->dev);

> > +       rda_gpio->chip.ngpio = ngpios;

> > +       rda_gpio->chip.base = -1;

> > +       rda_gpio->chip.parent = &pdev->dev;

> > +       rda_gpio->chip.of_node = np;

> > +       rda_gpio->chip.request = rda_gpio_request;

> > +       rda_gpio->chip.free = rda_gpio_free;

> > +       rda_gpio->chip.get = rda_gpio_get;

> > +       rda_gpio->chip.set = rda_gpio_set;

> > +       rda_gpio->chip.direction_input = rda_gpio_direction_input;

> > +       rda_gpio->chip.direction_output = rda_gpio_direction_output;

> > +

> > +       if (rda_gpio->irq >= 0) {

> > +               rda_gpio->irq_chip.name = "rda-gpio",

> > +               rda_gpio->irq_chip.irq_ack = rda_gpio_irq_ack,

> > +               rda_gpio->irq_chip.irq_mask = rda_gpio_irq_mask,

> > +               rda_gpio->irq_chip.irq_unmask = rda_gpio_irq_unmask,

> > +               rda_gpio->irq_chip.irq_set_type = rda_gpio_irq_set_type,

> > +               rda_gpio->irq_chip.flags = IRQCHIP_SKIP_SET_WAKE,

> > +

> > +               irq = &rda_gpio->chip.irq;

> > +               irq->chip = &rda_gpio->irq_chip;

> > +               irq->handler = handle_bad_irq;

> > +               irq->default_type = IRQ_TYPE_NONE;

> > +               irq->parent_handler = rda_gpio_irq_handler;

> > +               irq->parent_handler_data = rda_gpio;

> > +               irq->num_parents = 1;

> > +               irq->parents = &rda_gpio->irq;

> > +       }

> > +

> > +       ret = devm_gpiochip_add_data(&pdev->dev, &rda_gpio->chip, rda_gpio);

> 

> I'd simply do 'return devm_gpiochip_add_data()' here, not much else

> can fail in this driver's probe.

> 


okay. I'll just move the platform_set_drvdata() call up and return directly.

Thanks,
Mani

> Bart

> 

> > +       if (ret < 0) {

> > +               dev_err(&pdev->dev, "Could not register gpiochip %d\n", ret);

> > +               return ret;

> > +       }

> > +

> > +       platform_set_drvdata(pdev, rda_gpio);

> > +

> > +       return 0;

> > +}

> > +

> > +static const struct of_device_id rda_gpio_of_match[] = {

> > +       { .compatible = "rda,8810pl-gpio", },

> > +       { /* sentinel */ }

> > +};

> > +MODULE_DEVICE_TABLE(of, rda_gpio_of_match);

> > +

> > +static struct platform_driver rda_gpio_driver = {

> > +       .probe = rda_gpio_probe,

> > +       .driver = {

> > +               .name = "rda-gpio",

> > +               .of_match_table = rda_gpio_of_match,

> > +       },

> > +};

> > +

> > +module_platform_driver_probe(rda_gpio_driver, rda_gpio_probe);

> > +

> > +MODULE_DESCRIPTION("RDA Micro GPIO driver");

> > +MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");

> > +MODULE_LICENSE("GPL v2");

> > --

> > 2.17.1

> >