diff mbox series

[v20,2/3] Input: mt6779-keypad - Add MediaTek keypad driver

Message ID 20220127111526.3716689-3-mkorpershoek@baylibre.com
State Superseded
Headers show
Series Add matrix keypad driver support for Mediatek SoCs | expand

Commit Message

Mattijs Korpershoek Jan. 27, 2022, 11:15 a.m. UTC
From: "fengping.yu" <fengping.yu@mediatek.com>

This patch adds matrix keypad support for Mediatek SoCs.

Signed-off-by: fengping.yu <fengping.yu@mediatek.com>
Reviewed-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Signed-off-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
---
 drivers/input/keyboard/Kconfig         |  12 ++
 drivers/input/keyboard/Makefile        |   1 +
 drivers/input/keyboard/mt6779-keypad.c | 218 +++++++++++++++++++++++++
 3 files changed, 231 insertions(+)
 create mode 100644 drivers/input/keyboard/mt6779-keypad.c

Comments

Andy Shevchenko Jan. 27, 2022, 3:20 p.m. UTC | #1
On Thu, Jan 27, 2022 at 12:15:25PM +0100, Mattijs Korpershoek wrote:
> From: "fengping.yu" <fengping.yu@mediatek.com>
> 
> This patch adds matrix keypad support for Mediatek SoCs.

Some comments which may be addressed now or in the follow-up patch(es).
Up to you.

...

> +static const struct regmap_config mt6779_keypad_regmap_cfg = {
> +	.reg_bits = 32,
> +	.val_bits = 32,

> +	.reg_stride = sizeof(u32),

I'm wondering if we need this when we have reg_bits = 32 already.

> +	.max_register = 36,
> +};

...

> +	regmap_write(keypad->regmap, MTK_KPD_DEBOUNCE,
> +		     (debounce * 32) & MTK_KPD_DEBOUNCE_MASK);

I'm wondering if << 5 is more specific to show that the value
is based on 2^5 units.

...

> +	error = devm_add_action_or_reset(&pdev->dev, mt6779_keypad_clk_disable, keypad->clk);

You have this long line...

> +	error = devm_request_threaded_irq(&pdev->dev, irq,
> +					  NULL, mt6779_keypad_irq_handler,
> +					  IRQF_ONESHOT,
> +					  MTK_KPD_NAME, keypad);

...at the same time you may reduce LOCs here...

> +	if (error) {
> +		dev_err(&pdev->dev, "Failed to request IRQ#%d:%d\n",
> +			irq, error);

...and here.

> +		return error;
> +	}
Mattijs Korpershoek Jan. 28, 2022, 10:03 a.m. UTC | #2
On Thu, Jan 27, 2022 at 17:20, Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:

> On Thu, Jan 27, 2022 at 12:15:25PM +0100, Mattijs Korpershoek wrote:
>> From: "fengping.yu" <fengping.yu@mediatek.com>
>> 
>> This patch adds matrix keypad support for Mediatek SoCs.
>
> Some comments which may be addressed now or in the follow-up patch(es).
> Up to you.
Hi Andy,
Thank you for your review and your suggestions.

>
> ...
>
>> +static const struct regmap_config mt6779_keypad_regmap_cfg = {
>> +	.reg_bits = 32,
>> +	.val_bits = 32,
>
>> +	.reg_stride = sizeof(u32),
>
> I'm wondering if we need this when we have reg_bits = 32 already.

Per my understanding, .reg_stride is mainly used to check for invalid register
addresses in regmap_{read,write}():

    if (!IS_ALIGNED(reg, map->reg_stride))
            return -EINVAL;

If .reg_stride is not set, regmap core will default it to 1.
It's not computed from reg_bits.

So I think we still need it.
>
>> +	.max_register = 36,
>> +};
>
> ...
>
>> +	regmap_write(keypad->regmap, MTK_KPD_DEBOUNCE,
>> +		     (debounce * 32) & MTK_KPD_DEBOUNCE_MASK);
>
> I'm wondering if << 5 is more specific to show that the value
> is based on 2^5 units.

The datasheet I've seen states: "De-bounce time = KP_DEBOUNCE / 32ms"
But rewriting it as 1 << 5 seems reasonable as well:
regmap_write(keypad->regmap, MTK_KPD_DEBOUNCE,
            (debounce * (1 << 5)) & MTK_KPD_DEBOUNCE_MASK);

I don't have any preference on this one.
If I have to send a v21, I will rewrite it using (1 << 5)

>
> ...
>
>> +	error = devm_add_action_or_reset(&pdev->dev, mt6779_keypad_clk_disable, keypad->clk);
>
> You have this long line...
>
>> +	error = devm_request_threaded_irq(&pdev->dev, irq,
>> +					  NULL, mt6779_keypad_irq_handler,
>> +					  IRQF_ONESHOT,
>> +					  MTK_KPD_NAME, keypad);
>
> ...at the same time you may reduce LOCs here...
Ack. will join lines to reduce LOCs if I have to send v21.
>
>> +	if (error) {
>> +		dev_err(&pdev->dev, "Failed to request IRQ#%d:%d\n",
>> +			irq, error);
>
> ...and here.
Ack. will join lines to reduce LOCs if I have to send v21.

>
>> +		return error;
>> +	}
>
> -- 
> With Best Regards,
> Andy Shevchenko
Andy Shevchenko Jan. 28, 2022, 1:23 p.m. UTC | #3
On Fri, Jan 28, 2022 at 11:03:08AM +0100, Mattijs Korpershoek wrote:
> On Thu, Jan 27, 2022 at 17:20, Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> > On Thu, Jan 27, 2022 at 12:15:25PM +0100, Mattijs Korpershoek wrote:

...

> > Up to you.

> Thank you for your review and your suggestions.

Yes, as I said it you need a new version and consider them good.
Thanks!
diff mbox series

Patch

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index 0c607da9ee10..03a9530f620e 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -779,6 +779,18 @@  config KEYBOARD_BCM
 	  To compile this driver as a module, choose M here: the
 	  module will be called bcm-keypad.
 
+config KEYBOARD_MT6779
+	tristate "MediaTek Keypad Support"
+	depends on ARCH_MEDIATEK || COMPILE_TEST
+	select REGMAP_MMIO
+	select INPUT_MATRIXKMAP
+	help
+	  Say Y here if you want to use the keypad on MediaTek SoCs.
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called mt6779-keypad.
+
 config KEYBOARD_MTK_PMIC
 	tristate "MediaTek PMIC keys support"
 	depends on MFD_MT6397
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index e3c8648f834e..721936e90290 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -44,6 +44,7 @@  obj-$(CONFIG_KEYBOARD_MATRIX)		+= matrix_keypad.o
 obj-$(CONFIG_KEYBOARD_MAX7359)		+= max7359_keypad.o
 obj-$(CONFIG_KEYBOARD_MCS)		+= mcs_touchkey.o
 obj-$(CONFIG_KEYBOARD_MPR121)		+= mpr121_touchkey.o
+obj-$(CONFIG_KEYBOARD_MT6779)		+= mt6779-keypad.o
 obj-$(CONFIG_KEYBOARD_MTK_PMIC) 	+= mtk-pmic-keys.o
 obj-$(CONFIG_KEYBOARD_NEWTON)		+= newtonkbd.o
 obj-$(CONFIG_KEYBOARD_NOMADIK)		+= nomadik-ske-keypad.o
diff --git a/drivers/input/keyboard/mt6779-keypad.c b/drivers/input/keyboard/mt6779-keypad.c
new file mode 100644
index 000000000000..369366f18fd2
--- /dev/null
+++ b/drivers/input/keyboard/mt6779-keypad.c
@@ -0,0 +1,218 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022 MediaTek Inc.
+ * Author Fengping Yu <fengping.yu@mediatek.com>
+ */
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define MTK_KPD_NAME		"mt6779-keypad"
+#define MTK_KPD_MEM		0x0004
+#define MTK_KPD_DEBOUNCE	0x0018
+#define MTK_KPD_DEBOUNCE_MASK	GENMASK(13, 0)
+#define MTK_KPD_DEBOUNCE_MAX_MS	256
+#define MTK_KPD_NUM_MEMS	5
+#define MTK_KPD_NUM_BITS	136	/* 4*32+8 MEM5 only use 8 BITS */
+
+struct mt6779_keypad {
+	struct regmap *regmap;
+	struct input_dev *input_dev;
+	struct clk *clk;
+	void __iomem *base;
+	u32 n_rows;
+	u32 n_cols;
+	DECLARE_BITMAP(keymap_state, MTK_KPD_NUM_BITS);
+};
+
+static const struct regmap_config mt6779_keypad_regmap_cfg = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = sizeof(u32),
+	.max_register = 36,
+};
+
+static irqreturn_t mt6779_keypad_irq_handler(int irq, void *dev_id)
+{
+	struct mt6779_keypad *keypad = dev_id;
+	unsigned short *keycode = keypad->input_dev->keycode;
+	DECLARE_BITMAP(new_state, MTK_KPD_NUM_BITS);
+	DECLARE_BITMAP(change, MTK_KPD_NUM_BITS);
+	int bit_nr;
+	int pressed;
+	unsigned short code;
+	int row, col;
+	int row_shift = get_count_order(keypad->n_cols);
+
+	regmap_bulk_read(keypad->regmap, MTK_KPD_MEM,
+			 new_state, MTK_KPD_NUM_MEMS);
+
+	bitmap_xor(change, new_state, keypad->keymap_state, MTK_KPD_NUM_BITS);
+
+	for_each_set_bit(bit_nr, change, MTK_KPD_NUM_BITS) {
+	/* For 32bits register, only bits [15:0] use to indicate key status */
+		if (bit_nr % 32 >= 16)
+			continue;
+
+		/* 1: not pressed, 0: pressed */
+		pressed = !test_bit(bit_nr, new_state);
+		dev_dbg(&keypad->input_dev->dev, "%s",
+			pressed ? "pressed" : "released");
+
+		row = bit_nr / 32;
+		col = bit_nr % 32;
+
+		code = keycode[MATRIX_SCAN_CODE(row, col, row_shift)];
+
+		input_report_key(keypad->input_dev, code, pressed);
+		input_sync(keypad->input_dev);
+
+		dev_dbg(&keypad->input_dev->dev,
+			"report Linux keycode = %d\n", code);
+	}
+
+	bitmap_copy(keypad->keymap_state, new_state, MTK_KPD_NUM_BITS);
+
+	return IRQ_HANDLED;
+}
+
+static void mt6779_keypad_clk_disable(void *data)
+{
+	clk_disable_unprepare(data);
+}
+
+static int mt6779_keypad_pdrv_probe(struct platform_device *pdev)
+{
+	struct mt6779_keypad *keypad;
+	unsigned int irq;
+	u32 debounce;
+	bool wakeup;
+	int error;
+
+	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
+	if (!keypad)
+		return -ENOMEM;
+
+	keypad->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(keypad->base))
+		return PTR_ERR(keypad->base);
+
+	keypad->regmap = devm_regmap_init_mmio(&pdev->dev,
+					       keypad->base,
+					       &mt6779_keypad_regmap_cfg);
+	if (IS_ERR(keypad->regmap)) {
+		dev_err(&pdev->dev,
+			"regmap init failed:%pe\n", keypad->regmap);
+		return PTR_ERR(keypad->regmap);
+	}
+
+	bitmap_fill(keypad->keymap_state, MTK_KPD_NUM_BITS);
+
+	keypad->input_dev = devm_input_allocate_device(&pdev->dev);
+	if (!keypad->input_dev) {
+		dev_err(&pdev->dev, "Failed to allocate input dev\n");
+		return -ENOMEM;
+	}
+
+	keypad->input_dev->name = MTK_KPD_NAME;
+	keypad->input_dev->id.bustype = BUS_HOST;
+
+	error = matrix_keypad_parse_properties(&pdev->dev, &keypad->n_rows,
+					       &keypad->n_cols);
+	if (error) {
+		dev_err(&pdev->dev, "Failed to parse keypad params\n");
+		return error;
+	}
+
+	if (device_property_read_u32(&pdev->dev, "debounce-delay-ms",
+				     &debounce))
+		debounce = 16;
+
+	if (debounce > MTK_KPD_DEBOUNCE_MAX_MS) {
+		dev_err(&pdev->dev, "Debounce time exceeds the maximum allowed time %dms\n",
+			MTK_KPD_DEBOUNCE_MAX_MS);
+		return -EINVAL;
+	}
+
+	wakeup = device_property_read_bool(&pdev->dev, "wakeup-source");
+
+	dev_dbg(&pdev->dev, "n_row=%d n_col=%d debounce=%d\n",
+		keypad->n_rows, keypad->n_cols, debounce);
+
+	error = matrix_keypad_build_keymap(NULL, NULL,
+					   keypad->n_rows,
+					   keypad->n_cols,
+					   NULL,
+					   keypad->input_dev);
+	if (error) {
+		dev_err(&pdev->dev, "Failed to build keymap\n");
+		return error;
+	}
+
+	regmap_write(keypad->regmap, MTK_KPD_DEBOUNCE,
+		     (debounce * 32) & MTK_KPD_DEBOUNCE_MASK);
+
+	keypad->clk = devm_clk_get(&pdev->dev, "kpd");
+	if (IS_ERR(keypad->clk))
+		return PTR_ERR(keypad->clk);
+
+	error = clk_prepare_enable(keypad->clk);
+	if (error) {
+		dev_err(&pdev->dev, "cannot prepare/enable keypad clock\n");
+		return error;
+	}
+
+	error = devm_add_action_or_reset(&pdev->dev, mt6779_keypad_clk_disable, keypad->clk);
+	if (error)
+		return error;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	error = devm_request_threaded_irq(&pdev->dev, irq,
+					  NULL, mt6779_keypad_irq_handler,
+					  IRQF_ONESHOT,
+					  MTK_KPD_NAME, keypad);
+	if (error) {
+		dev_err(&pdev->dev, "Failed to request IRQ#%d:%d\n",
+			irq, error);
+		return error;
+	}
+
+	error = input_register_device(keypad->input_dev);
+	if (error) {
+		dev_err(&pdev->dev, "Failed to register device\n");
+		return error;
+	}
+
+	error =  device_init_wakeup(&pdev->dev, wakeup);
+	if (error)
+		dev_warn(&pdev->dev, "device_init_wakeup fail\n");
+
+	return 0;
+}
+
+static const struct of_device_id mt6779_keypad_of_match[] = {
+	{ .compatible = "mediatek,mt6779-keypad" },
+	{ .compatible = "mediatek,mt6873-keypad" },
+	{ /* sentinel */ }
+};
+
+static struct platform_driver mt6779_keypad_pdrv = {
+	.probe = mt6779_keypad_pdrv_probe,
+	.driver = {
+		   .name = MTK_KPD_NAME,
+		   .of_match_table = mt6779_keypad_of_match,
+	},
+};
+module_platform_driver(mt6779_keypad_pdrv);
+
+MODULE_AUTHOR("Mediatek Corporation");
+MODULE_DESCRIPTION("MTK Keypad (KPD) Driver");
+MODULE_LICENSE("GPL");