[V2,2/2] drivers: input: keyboard
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Message ID 20200108062923.14684-3-fengping.yu@mediatek.com
State New
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Series
  • [V2,1/2] Documentation: devicetree: bindings: input
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Commit Message

Fengping Yu Jan. 8, 2020, 6:29 a.m. UTC
From: "fengping.yu" <fengping.yu@mediatek.com>

add mtk keypad driver

Change-Id: I20bb26ee4112f51f60476b7ff7d6e42b43f729dc
Signed-off-by: fengping.yu <fengping.yu@mediatek.com>
---
 .../devicetree/bindings/input/mtk-kpd.txt     |  13 +-
 arch/arm64/configs/defconfig                  |   1 +
 drivers/input/keyboard/Kconfig                |   8 +
 drivers/input/keyboard/Makefile               |   1 +
 drivers/input/keyboard/mtk-kpd.c              | 357 ++++++++++++++++++
 5 files changed, 377 insertions(+), 3 deletions(-)
 create mode 100644 drivers/input/keyboard/mtk-kpd.c

Comments

Marco Felsch Jan. 8, 2020, 7:11 a.m. UTC | #1
Hi,

this is just a short review I did not check all details. Since this is a
v2 you should say what you changed.

Regards,
  Marco

On 20-01-08 14:29, fengping yu wrote:
> From: "fengping.yu" <fengping.yu@mediatek.com>
> 
> add mtk keypad driver

Hm.. can you explain it a bit more?

> Change-Id: I20bb26ee4112f51f60476b7ff7d6e42b43f729dc
> Signed-off-by: fengping.yu <fengping.yu@mediatek.com>
> ---
>  .../devicetree/bindings/input/mtk-kpd.txt     |  13 +-
>  arch/arm64/configs/defconfig                  |   1 +
>  drivers/input/keyboard/Kconfig                |   8 +
>  drivers/input/keyboard/Makefile               |   1 +
>  drivers/input/keyboard/mtk-kpd.c              | 357 ++++++++++++++++++
>  5 files changed, 377 insertions(+), 3 deletions(-)
>  create mode 100644 drivers/input/keyboard/mtk-kpd.c
> 
> diff --git a/Documentation/devicetree/bindings/input/mtk-kpd.txt b/Documentation/devicetree/bindings/input/mtk-kpd.txt
> index 2af81e696159..e3c17513c02c 100644
> --- a/Documentation/devicetree/bindings/input/mtk-kpd.txt
> +++ b/Documentation/devicetree/bindings/input/mtk-kpd.txt
> @@ -38,8 +38,15 @@ Example:
>  	};
>  
>  	&keypad {
> -		mediatek,key-debounce-ms = <1024>;
> +		mediatek,key-debounce-ms = <32>;
>  		/*HW Keycode [0~71] -> Linux Keycode*/
> -		mediatek,khw-map-num = <72>;
> -		mediatek,hw-init-map = <114 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >;
> +		mediatek,hw-map-num = <72>;
> +		mediatek,hw-init-map = <114 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0 >;
>  	};

This should be part of patch 1.

> diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
> index 8e05c39eab08..62bed77ec127 100644
> --- a/arch/arm64/configs/defconfig
> +++ b/arch/arm64/configs/defconfig
> @@ -315,6 +315,7 @@ CONFIG_KEYBOARD_ADC=m
>  CONFIG_KEYBOARD_GPIO=y
>  CONFIG_KEYBOARD_SNVS_PWRKEY=m
>  CONFIG_KEYBOARD_CROS_EC=y
> +CONFIG_KEYBOARD_MTK=y
>  CONFIG_INPUT_TOUCHSCREEN=y
>  CONFIG_TOUCHSCREEN_ATMEL_MXT=m
>  CONFIG_INPUT_MISC=y

This should be a extra patch.

> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 8911bc2ec42a..01747a97536b 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -775,4 +775,12 @@ config KEYBOARD_MTK_PMIC
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called pmic-keys.
>  
> +config KEYBOARD_MTK
> +	tristate "MediaTek Keypad Support"
> +	help
> +	  Say Y here if you want to use the keypad.
> +	  If unuse, say N.
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called mtk-kpd.
> +
>  endif
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index 9510325c0c5d..daa654bcce6e 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -41,6 +41,7 @@ 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-$(CONFIG_KEYBOARD_MTK) 		+= mtk-kpd.o
>  obj-$(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/mtk-kpd.c b/drivers/input/keyboard/mtk-kpd.c
> new file mode 100644
> index 000000000000..740a58b44dac
> --- /dev/null
> +++ b/drivers/input/keyboard/mtk-kpd.c
> @@ -0,0 +1,357 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2019 MediaTek Inc.
> + * Author Terry Chang <terry.chang@mediatek.com>
> + */
> +#include <linux/atomic.h>
> +#include <linux/clk.h>
> +#include <linux/debugfs.h>
> +#include <linux/delay.h>
> +#include <linux/fs.h>
> +#include <linux/gpio.h>
> +#include <linux/init.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/ioctl.h>
> +#include <linux/kernel.h>
> +#include <linux/miscdevice.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/pinctrl/consumer.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_wakeup.h>
> +#include <linux/regmap.h>
> +#include <linux/timer.h>
> +#include <linux/workqueue.h>

Please check if you need all these includes at least the workqueue isn't
required.

> +#define KPD_NAME	"mtk-kpd"
> +
> +#define KP_STA			(0x0000)
> +#define KP_MEM1			(0x0004)
> +#define KP_MEM2			(0x0008)
> +#define KP_MEM3			(0x000c)
> +#define KP_MEM4			(0x0010)
> +#define KP_MEM5			(0x0014)
> +#define KP_DEBOUNCE		(0x0018)
> +#define KP_SEL			(0x0020)
> +#define KP_EN			(0x0024)
> +
> +#define KP_COL0_SEL		(1 << 10)
> +#define KP_COL1_SEL		(1 << 11)
> +#define KP_COL2_SEL		(1 << 12)
> +
> +#define KPD_DEBOUNCE_MASK	((1U << 14) - 1)
> +#define KPD_DOUBLE_KEY_MASK	(1U << 0)
> +
> +#define KPD_NUM_MEMS	5
> +#define KPD_MEM5_BITS	8
> +#define KPD_NUM_KEYS	72	/* 4 * 16 + KPD_MEM5_BITS */
> +
> +struct mtk_keypad {
> +	struct input_dev *input_dev;
> +	struct wakeup_source *suspend_lock;
> +	struct tasklet_struct tasklet;

Why do you use a tasklet instead of a simple softirq?

> +	struct clk *clk;
> +	void __iomem *base;
> +	unsigned int irqnr;
> +	u32 key_debounce;
> +	u32 hw_map_num;
> +	u32 hw_init_map[KPD_NUM_KEYS];
> +	u16 keymap_state[KPD_NUM_MEMS];
> +};
> +
> +/* for keymap handling */
> +static void kpd_keymap_handler(unsigned long data);
> +
> +static int kpd_pdrv_probe(struct platform_device *pdev);

Why do you delcare these functions here?

> +static void kpd_get_keymap_state(void __iomem *kp_base, u16 state[])
> +{
> +	state[0] = readw(kp_base + KP_MEM1);
> +	state[1] = readw(kp_base + KP_MEM2);
> +	state[2] = readw(kp_base + KP_MEM3);
> +	state[3] = readw(kp_base + KP_MEM4);
> +	state[4] = readw(kp_base + KP_MEM5);
> +	pr_debug("kpd register = %x %x %x %x %x\n",
> +		 state[0], state[1], state[2], state[3], state[4]);
> +}
> +
> +static void kpd_keymap_handler(unsigned long data)
> +{
> +	int i, j;
> +	int pressed;
> +	u16 new_state[KPD_NUM_MEMS], change, mask;
> +	u16 hw_keycode, keycode;
> +	void *dest;
> +	struct mtk_keypad *keypad = (struct mtk_keypad *)data;
> +
> +	kpd_get_keymap_state(keypad->base, new_state);
> +
> +	__pm_wakeup_event(keypad->suspend_lock, 500);
> +
> +	for (i = 0; i < KPD_NUM_MEMS; i++) {
> +		change = new_state[i] ^ keypad->keymap_state[i];
> +		if (!change)
> +			continue;
> +
> +		for (j = 0; j < 16U; j++) {
> +			mask = (u16)1 << j;
> +			if (!(change & mask))
> +				continue;
> +
> +			hw_keycode = (i << 4) + j;
> +
> +			if (hw_keycode >= KPD_NUM_KEYS)
> +				continue;
> +
> +			/* bit is 1: not pressed, 0: pressed */
> +			pressed = (new_state[i] & mask) == 0U;
> +			pr_debug("(%s) HW keycode = %d\n",
> +				 (pressed) ? "pressed" : "released",
> +				 hw_keycode);
> +
> +			keycode = keypad->hw_init_map[hw_keycode];
> +			if (!keycode)
> +				continue;
> +			input_report_key(keypad->input_dev, keycode, pressed);
> +			input_sync(keypad->input_dev);
> +			pr_debug("report Linux keycode = %d\n", keycode);
> +		}
> +	}
> +
> +	dest = memcpy(keypad->keymap_state, new_state, sizeof(new_state));
> +	enable_irq(keypad->irqnr);
> +}
> +
> +static irqreturn_t kpd_irq_handler(int irq, void *dev_id)
> +{
> +	/* use _nosync to avoid deadlock */
> +	struct mtk_keypad *keypad = dev_id;
> +
> +	disable_irq_nosync(keypad->irqnr);
> +	tasklet_schedule(&keypad->tasklet);
> +	return IRQ_HANDLED;
> +}
> +
> +static int kpd_get_dts_info(struct mtk_keypad *keypad,
> +			    struct device_node *node)
> +{
> +	int ret;
> +
> +	ret = of_property_read_u32(node, "mediatek,key-debounce-ms",
> +				   &keypad->key_debounce);
> +	if (ret) {
> +		pr_debug("read mediatek,key-debounce-ms error.\n");
> +		return ret;
> +	}
> +
> +	ret = of_property_read_u32(node, "mediatek,hw-map-num",
> +				   &keypad->hw_map_num);
> +	if (ret) {
> +		pr_debug("read mediatek,hw-map-num error.\n");
> +		return ret;
> +	}
> +
> +	if (keypad->hw_map_num > KPD_NUM_KEYS) {
> +		pr_debug("hw-map-num error, it cannot bigger than %d.\n",
> +			 KPD_NUM_KEYS);
> +		return -EINVAL;
> +	}
> +
> +	ret = of_property_read_u32_array(node, "mediatek,hw-init-map",
> +					 keypad->hw_init_map,
> +					 keypad->hw_map_num);
> +
> +	if (ret) {
> +		pr_debug("hw-init-map was not defined in dts.\n");
> +		return ret;
> +	}
> +
> +	pr_debug("deb= %d\n", keypad->key_debounce);
> +
> +	return 0;
> +}
> +
> +static int kpd_gpio_init(struct device *dev)
> +{
> +	struct pinctrl *keypad_pinctrl;
> +	struct pinctrl_state *kpd_default;
> +
> +	keypad_pinctrl = devm_pinctrl_get(dev);
> +	if (IS_ERR(keypad_pinctrl)) {
> +		pr_debug("Cannot find keypad_pinctrl!\n");
> +
> +		return (int)PTR_ERR(keypad_pinctrl);
> +	}
> +
> +	kpd_default = pinctrl_lookup_state(keypad_pinctrl, "default");
> +	if (IS_ERR(kpd_default)) {
> +		pr_debug("Cannot find ecall_state!\n");
> +
> +		return (int)PTR_ERR(kpd_default);
> +	}
> +
> +	return pinctrl_select_state(keypad_pinctrl,
> +				kpd_default);
> +}
> +
> +static int kpd_pdrv_probe(struct platform_device *pdev)
> +{
> +	struct mtk_keypad *keypad;
> +	struct resource *res;
> +	int i;
> +	int err;
> +
> +	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
> +	if (!keypad)
> +		return -ENOMEM;
> +
> +	keypad->clk = devm_clk_get(&pdev->dev, "kpd");
> +	if (IS_ERR(keypad->clk)) {
> +		pr_notice("get kpd-clk fail: %d\n", (int)PTR_ERR(keypad->clk));
> +		return (int)PTR_ERR(keypad->clk);
> +	}

There is no need to cast it to (int).

> +
> +	err = clk_prepare_enable(keypad->clk);
> +	if (err) {
> +		pr_notice("kpd-clk prepare enable failed.\n");
> +		return err;
> +	}
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		err = -ENODEV;
> +		goto err_unprepare_clk;
> +	}
> +
> +	keypad->base = devm_ioremap(&pdev->dev, res->start,
> +				    resource_size(res));
> +	if (!keypad->base) {
> +		pr_notice("KP iomap failed\n");
> +		err = -EBUSY;
> +		goto err_unprepare_clk;
> +	}
> +
> +	keypad->irqnr = irq_of_parse_and_map(pdev->dev.of_node, 0);
> +	if (!keypad->irqnr) {
> +		pr_notice("KP get irqnr failed\n");
> +		err = -ENODEV;
> +		goto err_unprepare_clk;
> +	}
> +
> +	pr_info("kp base: 0x%p, addr:0x%p,  kp irq: %d\n",
> +		keypad->base, &keypad->base, keypad->irqnr);

Can we move that to pr_info.

> +	err = kpd_gpio_init(&pdev->dev);

This can be done here too but is jsut a nitpick.

> +	if (err) {
> +		pr_debug("gpio init failed\n");
> +		goto err_unprepare_clk;
> +	}
> +
> +	err = kpd_get_dts_info(keypad, pdev->dev.of_node);
> +	if (err) {
> +		pr_debug("get dts info failed.\n");
> +		goto err_unprepare_clk;
> +	}
> +
> +	memset(keypad->keymap_state, 0xff, sizeof(keypad->keymap_state));
> +
> +	keypad->input_dev = devm_input_allocate_device(&pdev->dev);
> +	if (!keypad->input_dev) {
> +		pr_notice("input allocate device fail.\n");
> +		err = -ENOMEM;
> +		goto err_unprepare_clk;
> +	}
> +
> +	keypad->input_dev->name = KPD_NAME;
> +	keypad->input_dev->id.bustype = BUS_HOST;
> +	keypad->input_dev->dev.parent = &pdev->dev;
> +
> +	__set_bit(EV_KEY, keypad->input_dev->evbit);
> +
> +	for (i = 0; i < KPD_NUM_KEYS; i++) {
> +		if (keypad->hw_init_map[i])
> +			__set_bit(keypad->hw_init_map[i],
> +				  keypad->input_dev->keybit);
> +	}
> +
> +	err = input_register_device(keypad->input_dev);
> +	if (err) {
> +		pr_notice("register input device failed (%d)\n", err);
> +		goto err_unprepare_clk;
> +	}
> +
> +	input_set_drvdata(keypad->input_dev, keypad);
> +
> +	keypad->suspend_lock = wakeup_source_register(NULL, "kpd wakelock");
> +	if (!keypad->suspend_lock) {
> +		pr_notice("wakeup source init failed.\n");
> +		err = -ENOMEM;
> +		goto err_unregister_device;
> +	}

What if someone won't use this device as wakeup source?

> +	tasklet_init(&keypad->tasklet, kpd_keymap_handler,
> +		     (unsigned long)keypad);
> +
> +	writew((u16)(keypad->key_debounce & KPD_DEBOUNCE_MASK),
> +		     keypad->base + KP_DEBOUNCE);
> +
> +	/* register IRQ */
> +	err = request_irq(keypad->irqnr, kpd_irq_handler, IRQF_TRIGGER_NONE,
> +			  KPD_NAME, keypad);
> +	if (err) {
> +		pr_notice("register IRQ failed (%d)\n", err);
> +		goto err_irq;
> +	}
> +
> +	pr_info("kpd_probe OK.\n");
> +
> +	return 0;
> +
> +err_irq:
> +	tasklet_kill(&keypad->tasklet);
> +	wakeup_source_unregister(keypad->suspend_lock);
> +
> +err_unregister_device:
> +	input_unregister_device(keypad->input_dev);
> +
> +err_unprepare_clk:
> +	clk_disable_unprepare(keypad->clk);
> +
> +	return err;
> +}
> +
> +static int kpd_pdrv_remove(struct platform_device *pdev)
> +{
> +	struct mtk_keypad *keypad = platform_get_drvdata(pdev);
> +
> +	tasklet_kill(&keypad->tasklet);
> +	wakeup_source_unregister(keypad->suspend_lock);
> +	input_unregister_device(keypad->input_dev);
> +	clk_disable_unprepare(keypad->clk);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id kpd_of_match[] = {
> +	{.compatible = "mediatek,mt6779-keypad"},
> +	{.compatible = "mediatek,kp"},
> +	{},
> +};
> +
> +static struct platform_driver kpd_pdrv = {
> +	.probe = kpd_pdrv_probe,
> +	.remove = kpd_pdrv_remove,
> +	.driver = {
> +		   .name = KPD_NAME,
> +		   .of_match_table = kpd_of_match,
> +		   },

Please align this correct.

> +};
> +
> +module_platform_driver(kpd_pdrv);
> +
> +MODULE_AUTHOR("Mediatek Corporation");
> +MODULE_DESCRIPTION("MTK Keypad (KPD) Driver");
> +MODULE_LICENSE("GPL");
> -- 
> 2.18.0
Marco Felsch Jan. 8, 2020, 7:23 a.m. UTC | #2
Hi,

On 20-01-08 08:11, Marco Felsch wrote:

...

> > +struct mtk_keypad {
> > +	struct input_dev *input_dev;
> > +	struct wakeup_source *suspend_lock;
> > +	struct tasklet_struct tasklet;
> 
> Why do you use a tasklet instead of a simple softirq?

Sorry, what I mean was a threaded_irq.

Regards,
  Marco
Yingjoe Chen Jan. 8, 2020, 8:46 a.m. UTC | #3
Hi, Fengping,


Macro already left some comments, I'll skip those.

The summary for this patch is not complete. Maybe you can use:

drivers: input: keyboard: add mtk-kpd driver


On Wed, 2020-01-08 at 14:29 +0800, fengping yu wrote:
> From: "fengping.yu" <fengping.yu@mediatek.com>
> 
> add mtk keypad driver
> 
> Change-Id: I20bb26ee4112f51f60476b7ff7d6e42b43f729dc

Please remove Change-Id

> Signed-off-by: fengping.yu <fengping.yu@mediatek.com>
> ---
>  .../devicetree/bindings/input/mtk-kpd.txt     |  13 +-
>  arch/arm64/configs/defconfig                  |   1 +
>  drivers/input/keyboard/Kconfig                |   8 +
>  drivers/input/keyboard/Makefile               |   1 +
>  drivers/input/keyboard/mtk-kpd.c              | 357 ++++++++++++++++++
>  5 files changed, 377 insertions(+), 3 deletions(-)
>  create mode 100644 drivers/input/keyboard/mtk-kpd.c
> 
> diff --git a/Documentation/devicetree/bindings/input/mtk-kpd.txt b/Documentation/devicetree/bindings/input/mtk-kpd.txt
> index 2af81e696159..e3c17513c02c 100644
> --- a/Documentation/devicetree/bindings/input/mtk-kpd.txt
> +++ b/Documentation/devicetree/bindings/input/mtk-kpd.txt
> @@ -38,8 +38,15 @@ Example:
>  	};
>  
>  	&keypad {
> -		mediatek,key-debounce-ms = <1024>;
> +		mediatek,key-debounce-ms = <32>;
>  		/*HW Keycode [0~71] -> Linux Keycode*/
> -		mediatek,khw-map-num = <72>;
> -		mediatek,hw-init-map = <114 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >;
> +		mediatek,hw-map-num = <72>;
> +		mediatek,hw-init-map = <114 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0 >;
>  	};
> diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
> index 8e05c39eab08..62bed77ec127 100644
> --- a/arch/arm64/configs/defconfig
> +++ b/arch/arm64/configs/defconfig
> @@ -315,6 +315,7 @@ CONFIG_KEYBOARD_ADC=m
>  CONFIG_KEYBOARD_GPIO=y
>  CONFIG_KEYBOARD_SNVS_PWRKEY=m
>  CONFIG_KEYBOARD_CROS_EC=y
> +CONFIG_KEYBOARD_MTK=y
>  CONFIG_INPUT_TOUCHSCREEN=y
>  CONFIG_TOUCHSCREEN_ATMEL_MXT=m
>  CONFIG_INPUT_MISC=y
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 8911bc2ec42a..01747a97536b 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -775,4 +775,12 @@ config KEYBOARD_MTK_PMIC
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called pmic-keys.
>  
> +config KEYBOARD_MTK

We already have KEYBOARD_MTK_PMIC, I think it make sense to call this
KEYBOARD_MTK_KPD to avoid confusion.
Please move this before KEYBOARD_MTK_PMIC.

> +	tristate "MediaTek Keypad Support"
> +	help
> +	  Say Y here if you want to use the keypad.
> +	  If unuse, say N.
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called mtk-kpd.
> +
>  endif
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index 9510325c0c5d..daa654bcce6e 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -41,6 +41,7 @@ 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-$(CONFIG_KEYBOARD_MTK) 		+= mtk-kpd.o
>  obj-$(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/mtk-kpd.c b/drivers/input/keyboard/mtk-kpd.c
> new file mode 100644
> index 000000000000..740a58b44dac
> --- /dev/null
> +++ b/drivers/input/keyboard/mtk-kpd.c
> @@ -0,0 +1,357 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2019 MediaTek Inc.
> + * Author Terry Chang <terry.chang@mediatek.com>
> + */
> +#include <linux/atomic.h>
> +#include <linux/clk.h>
> +#include <linux/debugfs.h>
> +#include <linux/delay.h>
> +#include <linux/fs.h>
> +#include <linux/gpio.h>
> +#include <linux/init.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/ioctl.h>
> +#include <linux/kernel.h>
> +#include <linux/miscdevice.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/pinctrl/consumer.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_wakeup.h>
> +#include <linux/regmap.h>
> +#include <linux/timer.h>
> +#include <linux/workqueue.h>
> +
> +#define KPD_NAME	"mtk-kpd"
> +
> +#define KP_STA			(0x0000)
> +#define KP_MEM1			(0x0004)
> +#define KP_MEM2			(0x0008)
> +#define KP_MEM3			(0x000c)
> +#define KP_MEM4			(0x0010)
> +#define KP_MEM5			(0x0014)
> +#define KP_DEBOUNCE		(0x0018)
> +#define KP_SEL			(0x0020)
> +#define KP_EN			(0x0024)

KP_STA/KP_SEL/KP_EN/KP_COL*_SEL is not used, please remove unused items

> +
> +#define KP_COL0_SEL		(1 << 10)
> +#define KP_COL1_SEL		(1 << 11)
> +#define KP_COL2_SEL		(1 << 12)
> +
> +#define KPD_DEBOUNCE_MASK	((1U << 14) - 1)
> +#define KPD_DOUBLE_KEY_MASK	(1U << 0)

Same here. Please add this when add double key support.

> +
> +#define KPD_NUM_MEMS	5
> +#define KPD_MEM5_BITS	8
> +#define KPD_NUM_KEYS	72	/* 4 * 16 + KPD_MEM5_BITS */
> +
> +struct mtk_keypad {
> +	struct input_dev *input_dev;
> +	struct wakeup_source *suspend_lock;
> +	struct tasklet_struct tasklet;
> +	struct clk *clk;
> +	void __iomem *base;
> +	unsigned int irqnr;
> +	u32 key_debounce;
> +	u32 hw_map_num;
> +	u32 hw_init_map[KPD_NUM_KEYS];
> +	u16 keymap_state[KPD_NUM_MEMS];
> +};
> +
> +/* for keymap handling */
> +static void kpd_keymap_handler(unsigned long data);
> +
> +static int kpd_pdrv_probe(struct platform_device *pdev);
> +
> +static void kpd_get_keymap_state(void __iomem *kp_base, u16 state[])
> +{
> +	state[0] = readw(kp_base + KP_MEM1);
> +	state[1] = readw(kp_base + KP_MEM2);
> +	state[2] = readw(kp_base + KP_MEM3);
> +	state[3] = readw(kp_base + KP_MEM4);
> +	state[4] = readw(kp_base + KP_MEM5);
> +	pr_debug("kpd register = %x %x %x %x %x\n",
> +		 state[0], state[1], state[2], state[3], state[4]);
> +}
> +
> +static void kpd_keymap_handler(unsigned long data)
> +{
> +	int i, j;
> +	int pressed;
> +	u16 new_state[KPD_NUM_MEMS], change, mask;
> +	u16 hw_keycode, keycode;
> +	void *dest;
> +	struct mtk_keypad *keypad = (struct mtk_keypad *)data;
> +
> +	kpd_get_keymap_state(keypad->base, new_state);
> +
> +	__pm_wakeup_event(keypad->suspend_lock, 500);
> +
> +	for (i = 0; i < KPD_NUM_MEMS; i++) {
> +		change = new_state[i] ^ keypad->keymap_state[i];
> +		if (!change)
> +			continue;
> +
> +		for (j = 0; j < 16U; j++) {
> +			mask = (u16)1 << j;
> +			if (!(change & mask))
> +				continue;
> +
> +			hw_keycode = (i << 4) + j;
> +
> +			if (hw_keycode >= KPD_NUM_KEYS)
> +				continue;
> +
> +			/* bit is 1: not pressed, 0: pressed */
> +			pressed = (new_state[i] & mask) == 0U;
> +			pr_debug("(%s) HW keycode = %d\n",
> +				 (pressed) ? "pressed" : "released",
> +				 hw_keycode);
> +
> +			keycode = keypad->hw_init_map[hw_keycode];
> +			if (!keycode)
> +				continue;
> +			input_report_key(keypad->input_dev, keycode, pressed);
> +			input_sync(keypad->input_dev);
> +			pr_debug("report Linux keycode = %d\n", keycode);
> +		}
> +	}
> +
> +	dest = memcpy(keypad->keymap_state, new_state, sizeof(new_state));
> +	enable_irq(keypad->irqnr);
> +}
> +
> +static irqreturn_t kpd_irq_handler(int irq, void *dev_id)
> +{
> +	/* use _nosync to avoid deadlock */
> +	struct mtk_keypad *keypad = dev_id;
> +
> +	disable_irq_nosync(keypad->irqnr);
> +	tasklet_schedule(&keypad->tasklet);
> +	return IRQ_HANDLED;
> +}
> +
> +static int kpd_get_dts_info(struct mtk_keypad *keypad,
> +			    struct device_node *node)
> +{
> +	int ret;
> +
> +	ret = of_property_read_u32(node, "mediatek,key-debounce-ms",
> +				   &keypad->key_debounce);

according to binding, maximum is 256ms.
Please add range check here.

> +	if (ret) {
> +		pr_debug("read mediatek,key-debounce-ms error.\n");
> +		return ret;
> +	}
> +
> +	ret = of_property_read_u32(node, "mediatek,hw-map-num",
> +				   &keypad->hw_map_num);
> +	if (ret) {
> +		pr_debug("read mediatek,hw-map-num error.\n");
> +		return ret;
> +	}
> +
> +	if (keypad->hw_map_num > KPD_NUM_KEYS) {
> +		pr_debug("hw-map-num error, it cannot bigger than %d.\n",
> +			 KPD_NUM_KEYS);
> +		return -EINVAL;
> +	}
> +
> +	ret = of_property_read_u32_array(node, "mediatek,hw-init-map",
> +					 keypad->hw_init_map,
> +					 keypad->hw_map_num);
> +
> +	if (ret) {
> +		pr_debug("hw-init-map was not defined in dts.\n");
> +		return ret;
> +	}
> +
> +	pr_debug("deb= %d\n", keypad->key_debounce);
> +
> +	return 0;
> +}
> +
> +static int kpd_gpio_init(struct device *dev)
> +{
> +	struct pinctrl *keypad_pinctrl;
> +	struct pinctrl_state *kpd_default;
> +
> +	keypad_pinctrl = devm_pinctrl_get(dev);
> +	if (IS_ERR(keypad_pinctrl)) {
> +		pr_debug("Cannot find keypad_pinctrl!\n");
> +
> +		return (int)PTR_ERR(keypad_pinctrl);
> +	}
> +
> +	kpd_default = pinctrl_lookup_state(keypad_pinctrl, "default");
> +	if (IS_ERR(kpd_default)) {
> +		pr_debug("Cannot find ecall_state!\n");
> +
> +		return (int)PTR_ERR(kpd_default);
> +	}
> +
> +	return pinctrl_select_state(keypad_pinctrl,
> +				kpd_default);
> +}
> +
> +static int kpd_pdrv_probe(struct platform_device *pdev)
> +{
> +	struct mtk_keypad *keypad;
> +	struct resource *res;
> +	int i;
> +	int err;
> +
> +	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
> +	if (!keypad)
> +		return -ENOMEM;
> +
> +	keypad->clk = devm_clk_get(&pdev->dev, "kpd");

this clk is not mentioned in dt binding. Please add it to binding.

> +	if (IS_ERR(keypad->clk)) {
> +		pr_notice("get kpd-clk fail: %d\n", (int)PTR_ERR(keypad->clk));
> +		return (int)PTR_ERR(keypad->clk);
> +	}
> +
> +	err = clk_prepare_enable(keypad->clk);
> +	if (err) {
> +		pr_notice("kpd-clk prepare enable failed.\n");
> +		return err;
> +	}
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		err = -ENODEV;
> +		goto err_unprepare_clk;
> +	}
> +
> +	keypad->base = devm_ioremap(&pdev->dev, res->start,
> +				    resource_size(res));

please use devm_platform_ioremap_resource instead of using
platform_get_resource+devm_ioremap


> +	if (!keypad->base) {
> +		pr_notice("KP iomap failed\n");
> +		err = -EBUSY;
> +		goto err_unprepare_clk;
> +	}
> +
> +	keypad->irqnr = irq_of_parse_and_map(pdev->dev.of_node, 0);
> +	if (!keypad->irqnr) {
> +		pr_notice("KP get irqnr failed\n");
> +		err = -ENODEV;
> +		goto err_unprepare_clk;
> +	}
> +
> +	pr_info("kp base: 0x%p, addr:0x%p,  kp irq: %d\n",
> +		keypad->base, &keypad->base, keypad->irqnr);

don't need 0x when you are using %p
But, I think we don't need this information

> +	err = kpd_gpio_init(&pdev->dev);

This init only set pinmux. Maybe you could just add code it here.

> +	if (err) {
> +		pr_debug("gpio init failed\n");
> +		goto err_unprepare_clk;
> +	}
> +
> +	err = kpd_get_dts_info(keypad, pdev->dev.of_node);
> +	if (err) {
> +		pr_debug("get dts info failed.\n");
> +		goto err_unprepare_clk;
> +	}
> +
> +	memset(keypad->keymap_state, 0xff, sizeof(keypad->keymap_state));
> +
> +	keypad->input_dev = devm_input_allocate_device(&pdev->dev);
> +	if (!keypad->input_dev) {
> +		pr_notice("input allocate device fail.\n");
> +		err = -ENOMEM;
> +		goto err_unprepare_clk;
> +	}
> +
> +	keypad->input_dev->name = KPD_NAME;
> +	keypad->input_dev->id.bustype = BUS_HOST;
> +	keypad->input_dev->dev.parent = &pdev->dev;
> +
> +	__set_bit(EV_KEY, keypad->input_dev->evbit);
> +
> +	for (i = 0; i < KPD_NUM_KEYS; i++) {
> +		if (keypad->hw_init_map[i])
> +			__set_bit(keypad->hw_init_map[i],
> +				  keypad->input_dev->keybit);
> +	}
> +
> +	err = input_register_device(keypad->input_dev);
> +	if (err) {
> +		pr_notice("register input device failed (%d)\n", err);
> +		goto err_unprepare_clk;
> +	}
> +
> +	input_set_drvdata(keypad->input_dev, keypad);
> +
> +	keypad->suspend_lock = wakeup_source_register(NULL, "kpd wakelock");
> +	if (!keypad->suspend_lock) {
> +		pr_notice("wakeup source init failed.\n");
> +		err = -ENOMEM;
> +		goto err_unregister_device;
> +	}
> +
> +	tasklet_init(&keypad->tasklet, kpd_keymap_handler,
> +		     (unsigned long)keypad);
> +
> +	writew((u16)(keypad->key_debounce & KPD_DEBOUNCE_MASK),
> +		     keypad->base + KP_DEBOUNCE);

You use a 13 bits mask and set it directly to KP_DEBOUNCE register. Are
you sure the debounce unit is ms?

> +
> +	/* register IRQ */
> +	err = request_irq(keypad->irqnr, kpd_irq_handler, IRQF_TRIGGER_NONE,
> +			  KPD_NAME, keypad);

please consider using devm_request_irq, otherwise you have to free it in
_remove function.

Joe.C


> +	if (err) {
> +		pr_notice("register IRQ failed (%d)\n", err);
> +		goto err_irq;
> +	}
> +
> +	pr_info("kpd_probe OK.\n");
> +
> +	return 0;
> +
> +err_irq:
> +	tasklet_kill(&keypad->tasklet);
> +	wakeup_source_unregister(keypad->suspend_lock);
> +
> +err_unregister_device:
> +	input_unregister_device(keypad->input_dev);
> +
> +err_unprepare_clk:
> +	clk_disable_unprepare(keypad->clk);
> +
> +	return err;
> +}
> +
> +static int kpd_pdrv_remove(struct platform_device *pdev)
> +{
> +	struct mtk_keypad *keypad = platform_get_drvdata(pdev);
> +
> +	tasklet_kill(&keypad->tasklet);
> +	wakeup_source_unregister(keypad->suspend_lock);
> +	input_unregister_device(keypad->input_dev);
> +	clk_disable_unprepare(keypad->clk);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id kpd_of_match[] = {
> +	{.compatible = "mediatek,mt6779-keypad"},
> +	{.compatible = "mediatek,kp"},
> +	{},
> +};
> +
> +static struct platform_driver kpd_pdrv = {
> +	.probe = kpd_pdrv_probe,
> +	.remove = kpd_pdrv_remove,
> +	.driver = {
> +		   .name = KPD_NAME,
> +		   .of_match_table = kpd_of_match,
> +		   },
> +};
> +
> +module_platform_driver(kpd_pdrv);
> +
> +MODULE_AUTHOR("Mediatek Corporation");
> +MODULE_DESCRIPTION("MTK Keypad (KPD) Driver");
> +MODULE_LICENSE("GPL");
Andy Shevchenko Jan. 8, 2020, 11:22 a.m. UTC | #4
On Wed, Jan 08, 2020 at 02:29:23PM +0800, fengping yu wrote:
> From: "fengping.yu" <fengping.yu@mediatek.com>
> 
> add mtk keypad driver

A bit more details, perhaps?
Also, what about proper English grammar and punctuation?

> Change-Id: I20bb26ee4112f51f60476b7ff7d6e42b43f729dc

Are you sure it's ready for upstream?

...

>  arch/arm64/configs/defconfig                  |   1 +

Why?

...

> --- a/Documentation/devicetree/bindings/input/mtk-kpd.txt
> +++ b/Documentation/devicetree/bindings/input/mtk-kpd.txt
> @@ -38,8 +38,15 @@ Example:
>  	};
>  
>  	&keypad {
> -		mediatek,key-debounce-ms = <1024>;
> +		mediatek,key-debounce-ms = <32>;
>  		/*HW Keycode [0~71] -> Linux Keycode*/
> -		mediatek,khw-map-num = <72>;
> -		mediatek,hw-init-map = <114 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >;
> +		mediatek,hw-map-num = <72>;
> +		mediatek,hw-init-map = <114 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0 >;
>  	};

Why above in this patch?

...

> +obj-$(CONFIG_KEYBOARD_MTK) 		+= mtk-kpd.o

TABs/spaces mix.

...

> +#include <linux/atomic.h>
> +#include <linux/clk.h>
> +#include <linux/debugfs.h>
> +#include <linux/delay.h>
> +#include <linux/fs.h>
> +#include <linux/gpio.h>
> +#include <linux/init.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/ioctl.h>
> +#include <linux/kernel.h>
> +#include <linux/miscdevice.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/pinctrl/consumer.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_wakeup.h>
> +#include <linux/regmap.h>
> +#include <linux/timer.h>
> +#include <linux/workqueue.h>

Do you really need all of them?!

...

> +#define KP_STA			(0x0000)
> +#define KP_MEM1			(0x0004)
> +#define KP_MEM2			(0x0008)
> +#define KP_MEM3			(0x000c)
> +#define KP_MEM4			(0x0010)
> +#define KP_MEM5			(0x0014)
> +#define KP_DEBOUNCE		(0x0018)
> +#define KP_SEL			(0x0020)
> +#define KP_EN			(0x0024)

What the purpose of parentheses?

...

> +#define KP_COL0_SEL		(1 << 10)
> +#define KP_COL1_SEL		(1 << 11)
> +#define KP_COL2_SEL		(1 << 12)

BIT()

> +#define KPD_DEBOUNCE_MASK	((1U << 14) - 1)
> +#define KPD_DOUBLE_KEY_MASK	(1U << 0)

GENMASK() / BIT_MASK() / BIT()

...

> +static int kpd_pdrv_probe(struct platform_device *pdev);

Why this forward declaration is present?

...

> +static void kpd_get_keymap_state(void __iomem *kp_base, u16 state[])
> +{
> +	state[0] = readw(kp_base + KP_MEM1);
> +	state[1] = readw(kp_base + KP_MEM2);
> +	state[2] = readw(kp_base + KP_MEM3);
> +	state[3] = readw(kp_base + KP_MEM4);
> +	state[4] = readw(kp_base + KP_MEM5);

> +	pr_debug("kpd register = %x %x %x %x %x\n",
> +		 state[0], state[1], state[2], state[3], state[4]);

Consider print_hex_dump() instead. But do you need this at all?

> +}

...

> +		for (j = 0; j < 16U; j++) {
> +			mask = (u16)1 << j;
> +			if (!(change & mask))
> +				continue;

for_each_set_bit() ?

> +		}

...

> +static int kpd_get_dts_info(struct mtk_keypad *keypad,
> +			    struct device_node *node)
> +{
> +	int ret;

Consider pr_*() -> dev_*() in all below code.

> +
> +	ret = of_property_read_u32(node, "mediatek,key-debounce-ms",
> +				   &keypad->key_debounce);
> +	if (ret) {
> +		pr_debug("read mediatek,key-debounce-ms error.\n");
> +		return ret;
> +	}
> +
> +	ret = of_property_read_u32(node, "mediatek,hw-map-num",
> +				   &keypad->hw_map_num);
> +	if (ret) {
> +		pr_debug("read mediatek,hw-map-num error.\n");
> +		return ret;
> +	}
> +
> +	if (keypad->hw_map_num > KPD_NUM_KEYS) {
> +		pr_debug("hw-map-num error, it cannot bigger than %d.\n",
> +			 KPD_NUM_KEYS);

dev_err() ?

> +		return -EINVAL;
> +	}
> +
> +	ret = of_property_read_u32_array(node, "mediatek,hw-init-map",
> +					 keypad->hw_init_map,
> +					 keypad->hw_map_num);
> +
> +	if (ret) {
> +		pr_debug("hw-init-map was not defined in dts.\n");
> +		return ret;
> +	}
> +
> +	pr_debug("deb= %d\n", keypad->key_debounce);
> +
> +	return 0;
> +}

It's for ARM64 which might support ACPI. Perhaps you may use device property
API instead of be OF-centric.

...

> +	keypad_pinctrl = devm_pinctrl_get(dev);
> +	if (IS_ERR(keypad_pinctrl)) {

> +		pr_debug("Cannot find keypad_pinctrl!\n");
> +

These kind of messages are not for production.

> +		return (int)PTR_ERR(keypad_pinctrl);

Why explicit casting? (Same for similar places all over the driver)
Is it really a fatal error?

> +	}

...

> +	return pinctrl_select_state(keypad_pinctrl,
> +				kpd_default);

One line. Perhaps you need to configure your text editor.

...

> +	keypad->clk = devm_clk_get(&pdev->dev, "kpd");
> +	if (IS_ERR(keypad->clk)) {

> +		pr_notice("get kpd-clk fail: %d\n", (int)PTR_ERR(keypad->clk));

Noise as a lot of such messages.

> +		return (int)PTR_ERR(keypad->clk);

Casting?!

> +	}

...

> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		err = -ENODEV;
> +		goto err_unprepare_clk;
> +	}
> +
> +	keypad->base = devm_ioremap(&pdev->dev, res->start,
> +				    resource_size(res));
> +	if (!keypad->base) {
> +		pr_notice("KP iomap failed\n");
> +		err = -EBUSY;
> +		goto err_unprepare_clk;
> +	}

What's wrong with devm_platform_ioremap_resource()?

...

> +	keypad->irqnr = irq_of_parse_and_map(pdev->dev.of_node, 0);
> +	if (!keypad->irqnr) {
> +		pr_notice("KP get irqnr failed\n");
> +		err = -ENODEV;
> +		goto err_unprepare_clk;
> +	}

Can't you use platform_get_irq()?
Why not?

...

> +	pr_info("kp base: 0x%p, addr:0x%p,  kp irq: %d\n",
> +		keypad->base, &keypad->base, keypad->irqnr);

Useless message. Moreover I believe it has wrong specifiers in use.

...

> +	memset(keypad->keymap_state, 0xff, sizeof(keypad->keymap_state));

Shouldn't be bitmap_fill()? In such case the variable has to be type of
unsigned long.

...

> +	writew((u16)(keypad->key_debounce & KPD_DEBOUNCE_MASK),
> +		     keypad->base + KP_DEBOUNCE);

Why explicit casting?

...

> +	/* register IRQ */
> +	err = request_irq(keypad->irqnr, kpd_irq_handler, IRQF_TRIGGER_NONE,
> +			  KPD_NAME, keypad);
> +	if (err) {
> +		pr_notice("register IRQ failed (%d)\n", err);
> +		goto err_irq;
> +	}

Why not threaded IRQ handler instead of ugly tasklet?

...

> +	pr_info("kpd_probe OK.\n");

Noise.

...

> +static const struct of_device_id kpd_of_match[] = {
> +	{.compatible = "mediatek,mt6779-keypad"},
> +	{.compatible = "mediatek,kp"},

> +	{},

Comma is not needed in terminator lines.

> +};
Andy Shevchenko Jan. 8, 2020, 11:26 a.m. UTC | #5
On Wed, Jan 08, 2020 at 04:46:02PM +0800, Yingjoe Chen wrote:
> On Wed, 2020-01-08 at 14:29 +0800, fengping yu wrote:

> > +	tasklet_init(&keypad->tasklet, kpd_keymap_handler,
> > +		     (unsigned long)keypad);
> > +
> > +	writew((u16)(keypad->key_debounce & KPD_DEBOUNCE_MASK),
> > +		     keypad->base + KP_DEBOUNCE);
> 
> You use a 13 bits mask and set it directly to KP_DEBOUNCE register. Are
> you sure the debounce unit is ms?
> 
> > +
> > +	/* register IRQ */
> > +	err = request_irq(keypad->irqnr, kpd_irq_handler, IRQF_TRIGGER_NONE,
> > +			  KPD_NAME, keypad);
> 
> please consider using devm_request_irq, otherwise you have to free it in
> _remove function.

No, you may not use devm_*_irq() when tasklets are in use. There is a nasty
race condition.

Actually the rule of thumb is to NOT use devm_*_irq() unless you exactly know
what you are doing.

P.S. Why simple not to switch to threaded IRQ handler and drop tasklet? In such
case devm_*_irq() is fine.
Dmitry Torokhov Jan. 10, 2020, 1:20 a.m. UTC | #6
On Wed, Jan 08, 2020 at 01:26:09PM +0200, Andy Shevchenko wrote:
> On Wed, Jan 08, 2020 at 04:46:02PM +0800, Yingjoe Chen wrote:
> > On Wed, 2020-01-08 at 14:29 +0800, fengping yu wrote:
> 
> > > +	tasklet_init(&keypad->tasklet, kpd_keymap_handler,
> > > +		     (unsigned long)keypad);
> > > +
> > > +	writew((u16)(keypad->key_debounce & KPD_DEBOUNCE_MASK),
> > > +		     keypad->base + KP_DEBOUNCE);
> > 
> > You use a 13 bits mask and set it directly to KP_DEBOUNCE register. Are
> > you sure the debounce unit is ms?
> > 
> > > +
> > > +	/* register IRQ */
> > > +	err = request_irq(keypad->irqnr, kpd_irq_handler, IRQF_TRIGGER_NONE,
> > > +			  KPD_NAME, keypad);
> > 
> > please consider using devm_request_irq, otherwise you have to free it in
> > _remove function.
> 
> No, you may not use devm_*_irq() when tasklets are in use. There is a nasty
> race condition.
> 
> Actually the rule of thumb is to NOT use devm_*_irq() unless you exactly know
> what you are doing.
> 
> P.S. Why simple not to switch to threaded IRQ handler and drop tasklet? In such
> case devm_*_irq() is fine.

Actually, we are simply reading iomem data and forward it to input
subsystem, there is no need to use threaded interrupt nor the tasklet.

Thanks.
Dmitry Torokhov Jan. 10, 2020, 1:32 a.m. UTC | #7
On Wed, Jan 08, 2020 at 02:29:23PM +0800, fengping yu wrote:
> From: "fengping.yu" <fengping.yu@mediatek.com>
> 
> add mtk keypad driver
> 
> Change-Id: I20bb26ee4112f51f60476b7ff7d6e42b43f729dc
> Signed-off-by: fengping.yu <fengping.yu@mediatek.com>
> ---
>  .../devicetree/bindings/input/mtk-kpd.txt     |  13 +-
>  arch/arm64/configs/defconfig                  |   1 +
>  drivers/input/keyboard/Kconfig                |   8 +
>  drivers/input/keyboard/Makefile               |   1 +
>  drivers/input/keyboard/mtk-kpd.c              | 357 ++++++++++++++++++
>  5 files changed, 377 insertions(+), 3 deletions(-)
>  create mode 100644 drivers/input/keyboard/mtk-kpd.c
> 
> diff --git a/Documentation/devicetree/bindings/input/mtk-kpd.txt b/Documentation/devicetree/bindings/input/mtk-kpd.txt
> index 2af81e696159..e3c17513c02c 100644
> --- a/Documentation/devicetree/bindings/input/mtk-kpd.txt
> +++ b/Documentation/devicetree/bindings/input/mtk-kpd.txt
> @@ -38,8 +38,15 @@ Example:
>  	};
>  
>  	&keypad {
> -		mediatek,key-debounce-ms = <1024>;
> +		mediatek,key-debounce-ms = <32>;
>  		/*HW Keycode [0~71] -> Linux Keycode*/
> -		mediatek,khw-map-num = <72>;
> -		mediatek,hw-init-map = <114 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >;
> +		mediatek,hw-map-num = <72>;
> +		mediatek,hw-init-map = <114 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0
> +															0 0 0 0 0 0 0 0 0 >;
>  	};
> diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
> index 8e05c39eab08..62bed77ec127 100644
> --- a/arch/arm64/configs/defconfig
> +++ b/arch/arm64/configs/defconfig
> @@ -315,6 +315,7 @@ CONFIG_KEYBOARD_ADC=m
>  CONFIG_KEYBOARD_GPIO=y
>  CONFIG_KEYBOARD_SNVS_PWRKEY=m
>  CONFIG_KEYBOARD_CROS_EC=y
> +CONFIG_KEYBOARD_MTK=y
>  CONFIG_INPUT_TOUCHSCREEN=y
>  CONFIG_TOUCHSCREEN_ATMEL_MXT=m
>  CONFIG_INPUT_MISC=y
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 8911bc2ec42a..01747a97536b 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -775,4 +775,12 @@ config KEYBOARD_MTK_PMIC
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called pmic-keys.
>  
> +config KEYBOARD_MTK
> +	tristate "MediaTek Keypad Support"
> +	help
> +	  Say Y here if you want to use the keypad.
> +	  If unuse, say N.
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called mtk-kpd.
> +
>  endif
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index 9510325c0c5d..daa654bcce6e 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -41,6 +41,7 @@ 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-$(CONFIG_KEYBOARD_MTK) 		+= mtk-kpd.o
>  obj-$(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/mtk-kpd.c b/drivers/input/keyboard/mtk-kpd.c
> new file mode 100644
> index 000000000000..740a58b44dac
> --- /dev/null
> +++ b/drivers/input/keyboard/mtk-kpd.c
> @@ -0,0 +1,357 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2019 MediaTek Inc.
> + * Author Terry Chang <terry.chang@mediatek.com>
> + */
> +#include <linux/atomic.h>
> +#include <linux/clk.h>
> +#include <linux/debugfs.h>
> +#include <linux/delay.h>
> +#include <linux/fs.h>
> +#include <linux/gpio.h>
> +#include <linux/init.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/ioctl.h>
> +#include <linux/kernel.h>
> +#include <linux/miscdevice.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/pinctrl/consumer.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_wakeup.h>
> +#include <linux/regmap.h>
> +#include <linux/timer.h>
> +#include <linux/workqueue.h>
> +
> +#define KPD_NAME	"mtk-kpd"
> +
> +#define KP_STA			(0x0000)
> +#define KP_MEM1			(0x0004)
> +#define KP_MEM2			(0x0008)
> +#define KP_MEM3			(0x000c)
> +#define KP_MEM4			(0x0010)
> +#define KP_MEM5			(0x0014)
> +#define KP_DEBOUNCE		(0x0018)
> +#define KP_SEL			(0x0020)
> +#define KP_EN			(0x0024)
> +
> +#define KP_COL0_SEL		(1 << 10)
> +#define KP_COL1_SEL		(1 << 11)
> +#define KP_COL2_SEL		(1 << 12)
> +
> +#define KPD_DEBOUNCE_MASK	((1U << 14) - 1)
> +#define KPD_DOUBLE_KEY_MASK	(1U << 0)
> +
> +#define KPD_NUM_MEMS	5
> +#define KPD_MEM5_BITS	8
> +#define KPD_NUM_KEYS	72	/* 4 * 16 + KPD_MEM5_BITS */
> +
> +struct mtk_keypad {
> +	struct input_dev *input_dev;
> +	struct wakeup_source *suspend_lock;
> +	struct tasklet_struct tasklet;
> +	struct clk *clk;
> +	void __iomem *base;
> +	unsigned int irqnr;
> +	u32 key_debounce;
> +	u32 hw_map_num;
> +	u32 hw_init_map[KPD_NUM_KEYS];
> +	u16 keymap_state[KPD_NUM_MEMS];
> +};
> +
> +/* for keymap handling */
> +static void kpd_keymap_handler(unsigned long data);
> +
> +static int kpd_pdrv_probe(struct platform_device *pdev);
> +
> +static void kpd_get_keymap_state(void __iomem *kp_base, u16 state[])
> +{
> +	state[0] = readw(kp_base + KP_MEM1);
> +	state[1] = readw(kp_base + KP_MEM2);
> +	state[2] = readw(kp_base + KP_MEM3);
> +	state[3] = readw(kp_base + KP_MEM4);
> +	state[4] = readw(kp_base + KP_MEM5);

Please use memcpy_formio() here.

> +	pr_debug("kpd register = %x %x %x %x %x\n",
> +		 state[0], state[1], state[2], state[3], state[4]);
> +}
> +
> +static void kpd_keymap_handler(unsigned long data)
> +{
> +	int i, j;
> +	int pressed;
> +	u16 new_state[KPD_NUM_MEMS], change, mask;
> +	u16 hw_keycode, keycode;
> +	void *dest;
> +	struct mtk_keypad *keypad = (struct mtk_keypad *)data;
> +
> +	kpd_get_keymap_state(keypad->base, new_state);
> +
> +	__pm_wakeup_event(keypad->suspend_lock, 500);
> +
> +	for (i = 0; i < KPD_NUM_MEMS; i++) {
> +		change = new_state[i] ^ keypad->keymap_state[i];
> +		if (!change)
> +			continue;
> +
> +		for (j = 0; j < 16U; j++) {
> +			mask = (u16)1 << j;
> +			if (!(change & mask))
> +				continue;

If you define state as N longs instead of M u16s, you can do

	for_each_set_bit()

as the single loop, figure row/col from offset, and get the state and
fetch the code from keymap.

> +
> +			hw_keycode = (i << 4) + j;
> +
> +			if (hw_keycode >= KPD_NUM_KEYS)
> +				continue;
> +
> +			/* bit is 1: not pressed, 0: pressed */
> +			pressed = (new_state[i] & mask) == 0U;
> +			pr_debug("(%s) HW keycode = %d\n",
> +				 (pressed) ? "pressed" : "released",
> +				 hw_keycode);
> +
> +			keycode = keypad->hw_init_map[hw_keycode];
> +			if (!keycode)
> +				continue;
> +			input_report_key(keypad->input_dev, keycode, pressed);
> +			input_sync(keypad->input_dev);
> +			pr_debug("report Linux keycode = %d\n", keycode);
> +		}
> +	}
> +
> +	dest = memcpy(keypad->keymap_state, new_state, sizeof(new_state));
> +	enable_irq(keypad->irqnr);
> +}
> +
> +static irqreturn_t kpd_irq_handler(int irq, void *dev_id)
> +{
> +	/* use _nosync to avoid deadlock */
> +	struct mtk_keypad *keypad = dev_id;
> +
> +	disable_irq_nosync(keypad->irqnr);
> +	tasklet_schedule(&keypad->tasklet);
> +	return IRQ_HANDLED;
> +}
> +
> +static int kpd_get_dts_info(struct mtk_keypad *keypad,
> +			    struct device_node *node)
> +{
> +	int ret;
> +
> +	ret = of_property_read_u32(node, "mediatek,key-debounce-ms",
> +				   &keypad->key_debounce);
> +	if (ret) {
> +		pr_debug("read mediatek,key-debounce-ms error.\n");
> +		return ret;
> +	}
> +
> +	ret = of_property_read_u32(node, "mediatek,hw-map-num",
> +				   &keypad->hw_map_num);
> +	if (ret) {
> +		pr_debug("read mediatek,hw-map-num error.\n");
> +		return ret;
> +	}
> +
> +	if (keypad->hw_map_num > KPD_NUM_KEYS) {
> +		pr_debug("hw-map-num error, it cannot bigger than %d.\n",
> +			 KPD_NUM_KEYS);
> +		return -EINVAL;
> +	}
> +
> +	ret = of_property_read_u32_array(node, "mediatek,hw-init-map",
> +					 keypad->hw_init_map,
> +					 keypad->hw_map_num);

As I mentioned, please use matrix keymap API and linux,keymap property.


> +
> +	if (ret) {
> +		pr_debug("hw-init-map was not defined in dts.\n");
> +		return ret;
> +	}
> +
> +	pr_debug("deb= %d\n", keypad->key_debounce);
> +
> +	return 0;
> +}
> +
> +static int kpd_gpio_init(struct device *dev)
> +{
> +	struct pinctrl *keypad_pinctrl;
> +	struct pinctrl_state *kpd_default;
> +
> +	keypad_pinctrl = devm_pinctrl_get(dev);
> +	if (IS_ERR(keypad_pinctrl)) {
> +		pr_debug("Cannot find keypad_pinctrl!\n");
> +
> +		return (int)PTR_ERR(keypad_pinctrl);
> +	}
> +
> +	kpd_default = pinctrl_lookup_state(keypad_pinctrl, "default");
> +	if (IS_ERR(kpd_default)) {
> +		pr_debug("Cannot find ecall_state!\n");
> +
> +		return (int)PTR_ERR(kpd_default);
> +	}
> +
> +	return pinctrl_select_state(keypad_pinctrl,
> +				kpd_default);
> +}
> +
> +static int kpd_pdrv_probe(struct platform_device *pdev)
> +{
> +	struct mtk_keypad *keypad;
> +	struct resource *res;
> +	int i;
> +	int err;
> +
> +	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
> +	if (!keypad)
> +		return -ENOMEM;
> +
> +	keypad->clk = devm_clk_get(&pdev->dev, "kpd");
> +	if (IS_ERR(keypad->clk)) {
> +		pr_notice("get kpd-clk fail: %d\n", (int)PTR_ERR(keypad->clk));
> +		return (int)PTR_ERR(keypad->clk);
> +	}
> +
> +	err = clk_prepare_enable(keypad->clk);

Do not mix devm and non-devm APIs. Use devm_add_action_or_reset() for
disabling clock in proper order.

> +	if (err) {
> +		pr_notice("kpd-clk prepare enable failed.\n");
> +		return err;
> +	}
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		err = -ENODEV;
> +		goto err_unprepare_clk;
> +	}
> +
> +	keypad->base = devm_ioremap(&pdev->dev, res->start,
> +				    resource_size(res));
> +	if (!keypad->base) {
> +		pr_notice("KP iomap failed\n");
> +		err = -EBUSY;
> +		goto err_unprepare_clk;
> +	}
> +
> +	keypad->irqnr = irq_of_parse_and_map(pdev->dev.of_node, 0);

Why is this done in the driver? Use platform_get_irq() instead.

> +	if (!keypad->irqnr) {
> +		pr_notice("KP get irqnr failed\n");
> +		err = -ENODEV;
> +		goto err_unprepare_clk;
> +	}
> +
> +	pr_info("kp base: 0x%p, addr:0x%p,  kp irq: %d\n",
> +		keypad->base, &keypad->base, keypad->irqnr);
> +	err = kpd_gpio_init(&pdev->dev);
> +	if (err) {
> +		pr_debug("gpio init failed\n");
> +		goto err_unprepare_clk;
> +	}
> +
> +	err = kpd_get_dts_info(keypad, pdev->dev.of_node);
> +	if (err) {
> +		pr_debug("get dts info failed.\n");
> +		goto err_unprepare_clk;
> +	}
> +
> +	memset(keypad->keymap_state, 0xff, sizeof(keypad->keymap_state));
> +
> +	keypad->input_dev = devm_input_allocate_device(&pdev->dev);
> +	if (!keypad->input_dev) {
> +		pr_notice("input allocate device fail.\n");
> +		err = -ENOMEM;
> +		goto err_unprepare_clk;
> +	}
> +
> +	keypad->input_dev->name = KPD_NAME;
> +	keypad->input_dev->id.bustype = BUS_HOST;
> +	keypad->input_dev->dev.parent = &pdev->dev;

No need to set this since you are using devm_input_allocate_device().

> +
> +	__set_bit(EV_KEY, keypad->input_dev->evbit);
> +
> +	for (i = 0; i < KPD_NUM_KEYS; i++) {
> +		if (keypad->hw_init_map[i])
> +			__set_bit(keypad->hw_init_map[i],
> +				  keypad->input_dev->keybit);
> +	}
> +
> +	err = input_register_device(keypad->input_dev);
> +	if (err) {
> +		pr_notice("register input device failed (%d)\n", err);
> +		goto err_unprepare_clk;
> +	}
> +
> +	input_set_drvdata(keypad->input_dev, keypad);
> +
> +	keypad->suspend_lock = wakeup_source_register(NULL, "kpd wakelock");
> +	if (!keypad->suspend_lock) {
> +		pr_notice("wakeup source init failed.\n");
> +		err = -ENOMEM;
> +		goto err_unregister_device;
> +	}

Why are we doing it in this fashion instead of checking "wakeup-source"
property and doing device_init_wakeup() when this flag is set?

> +
> +	tasklet_init(&keypad->tasklet, kpd_keymap_handler,
> +		     (unsigned long)keypad);

No need to use tasklet, you are not doing anything heavy in the ISR.

> +
> +	writew((u16)(keypad->key_debounce & KPD_DEBOUNCE_MASK),
> +		     keypad->base + KP_DEBOUNCE);
> +
> +	/* register IRQ */
> +	err = request_irq(keypad->irqnr, kpd_irq_handler, IRQF_TRIGGER_NONE,
> +			  KPD_NAME, keypad);
> +	if (err) {
> +		pr_notice("register IRQ failed (%d)\n", err);
> +		goto err_irq;
> +	}
> +
> +	pr_info("kpd_probe OK.\n");
> +
> +	return 0;
> +
> +err_irq:
> +	tasklet_kill(&keypad->tasklet);
> +	wakeup_source_unregister(keypad->suspend_lock);
> +
> +err_unregister_device:
> +	input_unregister_device(keypad->input_dev);
> +
> +err_unprepare_clk:
> +	clk_disable_unprepare(keypad->clk);
> +
> +	return err;
> +}
> +
> +static int kpd_pdrv_remove(struct platform_device *pdev)
> +{
> +	struct mtk_keypad *keypad = platform_get_drvdata(pdev);
> +
> +	tasklet_kill(&keypad->tasklet);
> +	wakeup_source_unregister(keypad->suspend_lock);
> +	input_unregister_device(keypad->input_dev);
> +	clk_disable_unprepare(keypad->clk);

Please remove this all and rely on devm for cleanup.

> +
> +	return 0;
> +}
> +
> +static const struct of_device_id kpd_of_match[] = {
> +	{.compatible = "mediatek,mt6779-keypad"},
> +	{.compatible = "mediatek,kp"},

Do we need both compatibles? Why?

> +	{},
> +};
> +
> +static struct platform_driver kpd_pdrv = {
> +	.probe = kpd_pdrv_probe,
> +	.remove = kpd_pdrv_remove,
> +	.driver = {
> +		   .name = KPD_NAME,
> +		   .of_match_table = kpd_of_match,
> +		   },
> +};
> +
> +module_platform_driver(kpd_pdrv);
> +
> +MODULE_AUTHOR("Mediatek Corporation");
> +MODULE_DESCRIPTION("MTK Keypad (KPD) Driver");
> +MODULE_LICENSE("GPL");
> -- 
> 2.18.0

Thanks.
Andy Shevchenko Jan. 10, 2020, 7:35 a.m. UTC | #8
On Fri, Jan 10, 2020 at 3:34 AM Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
> On Wed, Jan 08, 2020 at 02:29:23PM +0800, fengping yu wrote:
> > From: "fengping.yu" <fengping.yu@mediatek.com>

...

> > +static void kpd_get_keymap_state(void __iomem *kp_base, u16 state[])
> > +{
> > +     state[0] = readw(kp_base + KP_MEM1);
> > +     state[1] = readw(kp_base + KP_MEM2);
> > +     state[2] = readw(kp_base + KP_MEM3);
> > +     state[3] = readw(kp_base + KP_MEM4);
> > +     state[4] = readw(kp_base + KP_MEM5);
>
> Please use memcpy_formio() here.

Actually it's not an equivalent and may have side effects.
I already told somewhere that we lack of
mem*_*io{32,16,8}() implementation.

Patch
diff mbox series

diff --git a/Documentation/devicetree/bindings/input/mtk-kpd.txt b/Documentation/devicetree/bindings/input/mtk-kpd.txt
index 2af81e696159..e3c17513c02c 100644
--- a/Documentation/devicetree/bindings/input/mtk-kpd.txt
+++ b/Documentation/devicetree/bindings/input/mtk-kpd.txt
@@ -38,8 +38,15 @@  Example:
 	};
 
 	&keypad {
-		mediatek,key-debounce-ms = <1024>;
+		mediatek,key-debounce-ms = <32>;
 		/*HW Keycode [0~71] -> Linux Keycode*/
-		mediatek,khw-map-num = <72>;
-		mediatek,hw-init-map = <114 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >;
+		mediatek,hw-map-num = <72>;
+		mediatek,hw-init-map = <114 0 0 0 0 0 0 0 0
+															0 0 0 0 0 0 0 0 0
+															0 0 0 0 0 0 0 0 0
+															0 0 0 0 0 0 0 0 0
+															0 0 0 0 0 0 0 0 0
+															0 0 0 0 0 0 0 0 0
+															0 0 0 0 0 0 0 0 0
+															0 0 0 0 0 0 0 0 0 >;
 	};
diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 8e05c39eab08..62bed77ec127 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -315,6 +315,7 @@  CONFIG_KEYBOARD_ADC=m
 CONFIG_KEYBOARD_GPIO=y
 CONFIG_KEYBOARD_SNVS_PWRKEY=m
 CONFIG_KEYBOARD_CROS_EC=y
+CONFIG_KEYBOARD_MTK=y
 CONFIG_INPUT_TOUCHSCREEN=y
 CONFIG_TOUCHSCREEN_ATMEL_MXT=m
 CONFIG_INPUT_MISC=y
diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index 8911bc2ec42a..01747a97536b 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -775,4 +775,12 @@  config KEYBOARD_MTK_PMIC
 	  To compile this driver as a module, choose M here: the
 	  module will be called pmic-keys.
 
+config KEYBOARD_MTK
+	tristate "MediaTek Keypad Support"
+	help
+	  Say Y here if you want to use the keypad.
+	  If unuse, say N.
+	  To compile this driver as a module, choose M here: the
+	  module will be called mtk-kpd.
+
 endif
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 9510325c0c5d..daa654bcce6e 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -41,6 +41,7 @@  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-$(CONFIG_KEYBOARD_MTK) 		+= mtk-kpd.o
 obj-$(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/mtk-kpd.c b/drivers/input/keyboard/mtk-kpd.c
new file mode 100644
index 000000000000..740a58b44dac
--- /dev/null
+++ b/drivers/input/keyboard/mtk-kpd.c
@@ -0,0 +1,357 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 MediaTek Inc.
+ * Author Terry Chang <terry.chang@mediatek.com>
+ */
+#include <linux/atomic.h>
+#include <linux/clk.h>
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/gpio.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioctl.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/pm_wakeup.h>
+#include <linux/regmap.h>
+#include <linux/timer.h>
+#include <linux/workqueue.h>
+
+#define KPD_NAME	"mtk-kpd"
+
+#define KP_STA			(0x0000)
+#define KP_MEM1			(0x0004)
+#define KP_MEM2			(0x0008)
+#define KP_MEM3			(0x000c)
+#define KP_MEM4			(0x0010)
+#define KP_MEM5			(0x0014)
+#define KP_DEBOUNCE		(0x0018)
+#define KP_SEL			(0x0020)
+#define KP_EN			(0x0024)
+
+#define KP_COL0_SEL		(1 << 10)
+#define KP_COL1_SEL		(1 << 11)
+#define KP_COL2_SEL		(1 << 12)
+
+#define KPD_DEBOUNCE_MASK	((1U << 14) - 1)
+#define KPD_DOUBLE_KEY_MASK	(1U << 0)
+
+#define KPD_NUM_MEMS	5
+#define KPD_MEM5_BITS	8
+#define KPD_NUM_KEYS	72	/* 4 * 16 + KPD_MEM5_BITS */
+
+struct mtk_keypad {
+	struct input_dev *input_dev;
+	struct wakeup_source *suspend_lock;
+	struct tasklet_struct tasklet;
+	struct clk *clk;
+	void __iomem *base;
+	unsigned int irqnr;
+	u32 key_debounce;
+	u32 hw_map_num;
+	u32 hw_init_map[KPD_NUM_KEYS];
+	u16 keymap_state[KPD_NUM_MEMS];
+};
+
+/* for keymap handling */
+static void kpd_keymap_handler(unsigned long data);
+
+static int kpd_pdrv_probe(struct platform_device *pdev);
+
+static void kpd_get_keymap_state(void __iomem *kp_base, u16 state[])
+{
+	state[0] = readw(kp_base + KP_MEM1);
+	state[1] = readw(kp_base + KP_MEM2);
+	state[2] = readw(kp_base + KP_MEM3);
+	state[3] = readw(kp_base + KP_MEM4);
+	state[4] = readw(kp_base + KP_MEM5);
+	pr_debug("kpd register = %x %x %x %x %x\n",
+		 state[0], state[1], state[2], state[3], state[4]);
+}
+
+static void kpd_keymap_handler(unsigned long data)
+{
+	int i, j;
+	int pressed;
+	u16 new_state[KPD_NUM_MEMS], change, mask;
+	u16 hw_keycode, keycode;
+	void *dest;
+	struct mtk_keypad *keypad = (struct mtk_keypad *)data;
+
+	kpd_get_keymap_state(keypad->base, new_state);
+
+	__pm_wakeup_event(keypad->suspend_lock, 500);
+
+	for (i = 0; i < KPD_NUM_MEMS; i++) {
+		change = new_state[i] ^ keypad->keymap_state[i];
+		if (!change)
+			continue;
+
+		for (j = 0; j < 16U; j++) {
+			mask = (u16)1 << j;
+			if (!(change & mask))
+				continue;
+
+			hw_keycode = (i << 4) + j;
+
+			if (hw_keycode >= KPD_NUM_KEYS)
+				continue;
+
+			/* bit is 1: not pressed, 0: pressed */
+			pressed = (new_state[i] & mask) == 0U;
+			pr_debug("(%s) HW keycode = %d\n",
+				 (pressed) ? "pressed" : "released",
+				 hw_keycode);
+
+			keycode = keypad->hw_init_map[hw_keycode];
+			if (!keycode)
+				continue;
+			input_report_key(keypad->input_dev, keycode, pressed);
+			input_sync(keypad->input_dev);
+			pr_debug("report Linux keycode = %d\n", keycode);
+		}
+	}
+
+	dest = memcpy(keypad->keymap_state, new_state, sizeof(new_state));
+	enable_irq(keypad->irqnr);
+}
+
+static irqreturn_t kpd_irq_handler(int irq, void *dev_id)
+{
+	/* use _nosync to avoid deadlock */
+	struct mtk_keypad *keypad = dev_id;
+
+	disable_irq_nosync(keypad->irqnr);
+	tasklet_schedule(&keypad->tasklet);
+	return IRQ_HANDLED;
+}
+
+static int kpd_get_dts_info(struct mtk_keypad *keypad,
+			    struct device_node *node)
+{
+	int ret;
+
+	ret = of_property_read_u32(node, "mediatek,key-debounce-ms",
+				   &keypad->key_debounce);
+	if (ret) {
+		pr_debug("read mediatek,key-debounce-ms error.\n");
+		return ret;
+	}
+
+	ret = of_property_read_u32(node, "mediatek,hw-map-num",
+				   &keypad->hw_map_num);
+	if (ret) {
+		pr_debug("read mediatek,hw-map-num error.\n");
+		return ret;
+	}
+
+	if (keypad->hw_map_num > KPD_NUM_KEYS) {
+		pr_debug("hw-map-num error, it cannot bigger than %d.\n",
+			 KPD_NUM_KEYS);
+		return -EINVAL;
+	}
+
+	ret = of_property_read_u32_array(node, "mediatek,hw-init-map",
+					 keypad->hw_init_map,
+					 keypad->hw_map_num);
+
+	if (ret) {
+		pr_debug("hw-init-map was not defined in dts.\n");
+		return ret;
+	}
+
+	pr_debug("deb= %d\n", keypad->key_debounce);
+
+	return 0;
+}
+
+static int kpd_gpio_init(struct device *dev)
+{
+	struct pinctrl *keypad_pinctrl;
+	struct pinctrl_state *kpd_default;
+
+	keypad_pinctrl = devm_pinctrl_get(dev);
+	if (IS_ERR(keypad_pinctrl)) {
+		pr_debug("Cannot find keypad_pinctrl!\n");
+
+		return (int)PTR_ERR(keypad_pinctrl);
+	}
+
+	kpd_default = pinctrl_lookup_state(keypad_pinctrl, "default");
+	if (IS_ERR(kpd_default)) {
+		pr_debug("Cannot find ecall_state!\n");
+
+		return (int)PTR_ERR(kpd_default);
+	}
+
+	return pinctrl_select_state(keypad_pinctrl,
+				kpd_default);
+}
+
+static int kpd_pdrv_probe(struct platform_device *pdev)
+{
+	struct mtk_keypad *keypad;
+	struct resource *res;
+	int i;
+	int err;
+
+	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
+	if (!keypad)
+		return -ENOMEM;
+
+	keypad->clk = devm_clk_get(&pdev->dev, "kpd");
+	if (IS_ERR(keypad->clk)) {
+		pr_notice("get kpd-clk fail: %d\n", (int)PTR_ERR(keypad->clk));
+		return (int)PTR_ERR(keypad->clk);
+	}
+
+	err = clk_prepare_enable(keypad->clk);
+	if (err) {
+		pr_notice("kpd-clk prepare enable failed.\n");
+		return err;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		err = -ENODEV;
+		goto err_unprepare_clk;
+	}
+
+	keypad->base = devm_ioremap(&pdev->dev, res->start,
+				    resource_size(res));
+	if (!keypad->base) {
+		pr_notice("KP iomap failed\n");
+		err = -EBUSY;
+		goto err_unprepare_clk;
+	}
+
+	keypad->irqnr = irq_of_parse_and_map(pdev->dev.of_node, 0);
+	if (!keypad->irqnr) {
+		pr_notice("KP get irqnr failed\n");
+		err = -ENODEV;
+		goto err_unprepare_clk;
+	}
+
+	pr_info("kp base: 0x%p, addr:0x%p,  kp irq: %d\n",
+		keypad->base, &keypad->base, keypad->irqnr);
+	err = kpd_gpio_init(&pdev->dev);
+	if (err) {
+		pr_debug("gpio init failed\n");
+		goto err_unprepare_clk;
+	}
+
+	err = kpd_get_dts_info(keypad, pdev->dev.of_node);
+	if (err) {
+		pr_debug("get dts info failed.\n");
+		goto err_unprepare_clk;
+	}
+
+	memset(keypad->keymap_state, 0xff, sizeof(keypad->keymap_state));
+
+	keypad->input_dev = devm_input_allocate_device(&pdev->dev);
+	if (!keypad->input_dev) {
+		pr_notice("input allocate device fail.\n");
+		err = -ENOMEM;
+		goto err_unprepare_clk;
+	}
+
+	keypad->input_dev->name = KPD_NAME;
+	keypad->input_dev->id.bustype = BUS_HOST;
+	keypad->input_dev->dev.parent = &pdev->dev;
+
+	__set_bit(EV_KEY, keypad->input_dev->evbit);
+
+	for (i = 0; i < KPD_NUM_KEYS; i++) {
+		if (keypad->hw_init_map[i])
+			__set_bit(keypad->hw_init_map[i],
+				  keypad->input_dev->keybit);
+	}
+
+	err = input_register_device(keypad->input_dev);
+	if (err) {
+		pr_notice("register input device failed (%d)\n", err);
+		goto err_unprepare_clk;
+	}
+
+	input_set_drvdata(keypad->input_dev, keypad);
+
+	keypad->suspend_lock = wakeup_source_register(NULL, "kpd wakelock");
+	if (!keypad->suspend_lock) {
+		pr_notice("wakeup source init failed.\n");
+		err = -ENOMEM;
+		goto err_unregister_device;
+	}
+
+	tasklet_init(&keypad->tasklet, kpd_keymap_handler,
+		     (unsigned long)keypad);
+
+	writew((u16)(keypad->key_debounce & KPD_DEBOUNCE_MASK),
+		     keypad->base + KP_DEBOUNCE);
+
+	/* register IRQ */
+	err = request_irq(keypad->irqnr, kpd_irq_handler, IRQF_TRIGGER_NONE,
+			  KPD_NAME, keypad);
+	if (err) {
+		pr_notice("register IRQ failed (%d)\n", err);
+		goto err_irq;
+	}
+
+	pr_info("kpd_probe OK.\n");
+
+	return 0;
+
+err_irq:
+	tasklet_kill(&keypad->tasklet);
+	wakeup_source_unregister(keypad->suspend_lock);
+
+err_unregister_device:
+	input_unregister_device(keypad->input_dev);
+
+err_unprepare_clk:
+	clk_disable_unprepare(keypad->clk);
+
+	return err;
+}
+
+static int kpd_pdrv_remove(struct platform_device *pdev)
+{
+	struct mtk_keypad *keypad = platform_get_drvdata(pdev);
+
+	tasklet_kill(&keypad->tasklet);
+	wakeup_source_unregister(keypad->suspend_lock);
+	input_unregister_device(keypad->input_dev);
+	clk_disable_unprepare(keypad->clk);
+
+	return 0;
+}
+
+static const struct of_device_id kpd_of_match[] = {
+	{.compatible = "mediatek,mt6779-keypad"},
+	{.compatible = "mediatek,kp"},
+	{},
+};
+
+static struct platform_driver kpd_pdrv = {
+	.probe = kpd_pdrv_probe,
+	.remove = kpd_pdrv_remove,
+	.driver = {
+		   .name = KPD_NAME,
+		   .of_match_table = kpd_of_match,
+		   },
+};
+
+module_platform_driver(kpd_pdrv);
+
+MODULE_AUTHOR("Mediatek Corporation");
+MODULE_DESCRIPTION("MTK Keypad (KPD) Driver");
+MODULE_LICENSE("GPL");