[PATCH v16] Add matrix keypad driver support for Mediatek SoCs

[PATCH v16] Add matrix keypad driver support for Mediatek SoCs

[Fengping Yu]

Change since v15:
- modify regmap_raw_read to regmap_bulk_read
- modify regmap output specifier to %pe

fengping.yu (3):
  dt-bindings: Add keypad devicetree documentation
  drivers: input: keyboard: Add mtk keypad driver
  configs: defconfig: Add CONFIG_KEYBOARD_MTK_KPD=m

 .../devicetree/bindings/input/mtk-kpd.yaml    |  96 ++++++++
 arch/arm64/configs/defconfig                  |   1 +
 drivers/input/keyboard/Kconfig                |  11 +
 drivers/input/keyboard/Makefile               |   1 +
 drivers/input/keyboard/mtk-kpd.c              | 209 ++++++++++++++++++
 5 files changed, 318 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/input/mtk-kpd.yaml
 create mode 100644 drivers/input/keyboard/mtk-kpd.c

--
2.18.0

Re: [PATCH v16 2/3] drivers: input: keyboard: Add mtk keypad driver

[Mattijs Korpershoek]

Hi Fengping,

Fengping Yu <fengping.yu@mediatek.com> writes:

> From: "fengping.yu" <fengping.yu@mediatek.com>
>
> This 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>

> ---
>  drivers/input/keyboard/Kconfig   |  11 ++
>  drivers/input/keyboard/Makefile  |   1 +
>  drivers/input/keyboard/mtk-kpd.c | 209 +++++++++++++++++++++++++++++++
>  3 files changed, 221 insertions(+)
>  create mode 100644 drivers/input/keyboard/mtk-kpd.c
>
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 793ecbbda32c..1ee845c292c6 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -782,6 +782,17 @@ config KEYBOARD_BCM
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called bcm-keypad.
>  
> +config KEYBOARD_MTK_KPD
> +	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 mtk-kpd.
> +
>  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 1d689fdd5c00..6c9d852c377e 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -43,6 +43,7 @@ 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-$(CONFIG_KEYBOARD_MTK_KPD)		+= mtk-kpd.o
>  obj-$(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..451b3bc61c6f
> --- /dev/null
> +++ b/drivers/input/keyboard/mtk-kpd.c
> @@ -0,0 +1,209 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2019 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		"mtk-kpd"
> +#define MTK_KPD_MEM		0x0004
> +#define MTK_KPD_DEBOUNCE	0x0018
> +#define MTK_KPD_DEBOUNCE_MASK	GENMASK(13, 0)
> +#define MTK_KPD_DEBOUNCE_MAX_US	256000
> +#define MTK_KPD_NUM_MEMS	5
> +#define MTK_KPD_NUM_BITS	136	/* 4*32+8 MEM5 only use 8 BITS */
> +
> +struct mtk_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 keypad_regmap_cfg = {
> +	.reg_bits = 32,
> +	.val_bits = 32,
> +	.reg_stride = sizeof(u32),
> +	.max_register = 36,
> +};
> +
> +static irqreturn_t kpd_irq_handler(int irq, void *dev_id)
> +{
> +	struct mtk_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;
> +
> +	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) {
> +		/* 1: not pressed, 0: pressed */
> +		pressed = !test_bit(bit_nr, new_state);
> +		dev_dbg(&keypad->input_dev->dev, "%s",
> +			pressed ? "pressed" : "released");
> +
> +		/* 32bit register only use low 16bit as keypad mem register */
> +		code = keycode[bit_nr - 16 * (BITS_TO_U32(bit_nr) - 1)];
> +
> +		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 kpd_clk_disable(void *data)
> +{
> +	clk_disable_unprepare(data);
> +}
> +
> +static int kpd_pdrv_probe(struct platform_device *pdev)
> +{
> +	struct mtk_keypad *keypad;
> +	unsigned int irq;
> +	u32 debounce;
> +	bool wakeup;
> +	int ret;
> +
> +	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,
> +					       &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;
> +
> +	ret = matrix_keypad_parse_properties(&pdev->dev, &keypad->n_rows,
> +					     &keypad->n_cols);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to parse keypad params\n");
> +		return ret;
> +	}
> +
> +	if (device_property_read_u32(&pdev->dev, "mediatek,debounce-us",
> +				     &debounce))
> +		debounce = 16000;
> +
> +	if (debounce > MTK_KPD_DEBOUNCE_MAX_US) {
> +		dev_err(&pdev->dev, "Debounce time exceeds the maximum allowed time %dus\n",
> +			MTK_KPD_DEBOUNCE_MAX_US);
> +		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);
> +
> +	ret = matrix_keypad_build_keymap(NULL, NULL,
> +					 keypad->n_rows,
> +					 keypad->n_cols,
> +					 NULL,
> +					 keypad->input_dev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to build keymap\n");
> +		return ret;
> +	}
> +
> +	regmap_write(keypad->regmap, MTK_KPD_DEBOUNCE,
> +		     debounce * 32 / 1000 & MTK_KPD_DEBOUNCE_MASK);
> +
> +	keypad->clk = devm_clk_get(&pdev->dev, "kpd");
> +	if (IS_ERR(keypad->clk))
> +		return PTR_ERR(keypad->clk);
> +
> +	ret = clk_prepare_enable(keypad->clk);
> +	if (ret) {
> +		dev_err(&pdev->dev, "cannot prepare/enable keypad clock\n");
> +		return ret;
> +	}
> +
> +	ret = devm_add_action_or_reset(&pdev->dev, kpd_clk_disable, keypad->clk);
> +	if (ret)
> +		return ret;
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +
> +	ret = devm_request_threaded_irq(&pdev->dev, irq,
> +					NULL, kpd_irq_handler, IRQF_ONESHOT,
> +					MTK_KPD_NAME, keypad);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to request IRQ#%d:%d\n",
> +			irq, ret);
> +		return ret;
> +	}
> +
> +	ret = input_register_device(keypad->input_dev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to register device\n");
> +		return ret;
> +	}
> +
> +	ret =  device_init_wakeup(&pdev->dev, wakeup);
> +	if (ret)
> +		dev_warn(&pdev->dev, "device_init_wakeup fail\n");
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id kpd_of_match[] = {
> +	{ .compatible = "mediatek,mt6779-keypad" },
> +	{ .compatible = "mediatek,mt6873-keypad" },
> +	{ /* sentinel */ }
> +};
> +
> +static struct platform_driver kpd_pdrv = {
> +	.probe = kpd_pdrv_probe,
> +	.driver = {
> +		   .name = MTK_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");

Re: [PATCH v16 1/3] dt-bindings: Add keypad devicetree documentation

[Yingjoe Chen]

Hi,

Summary should specified this patch is for MediaTek:

dt-bindings: add MediaTek keypad devicetree documentation


On Mon, 2020-07-27 at 19:45 +0800, Fengping Yu wrote:
> From: "fengping.yu" <fengping.yu@mediatek.com>

> Add Mediatek matrix keypad dt-bindings doc as yaml schema.
> 
> Signed-off-by: fengping.yu <fengping.yu@mediatek.com>
> ---
>  .../devicetree/bindings/input/mtk-kpd.yaml    | 96 +++++++++++++++++++
>  1 file changed, 96 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/input/mtk-kpd.yaml
> 
> diff --git a/Documentation/devicetree/bindings/input/mtk-kpd.yaml b/Documentation/devicetree/bindings/input/mtk-kpd.yaml
> new file mode 100644
> index 000000000000..3bf09e7395d0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/mtk-kpd.yaml
> @@ -0,0 +1,96 @@
> +# SPDX-License-Identifier: GPL-2.0
> +%YAML 1.2
> +---
> +version: 1
> +
> +$id: http://devicetree.org/schemas/input/mtk-keypad.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Mediatek's Keypad Controller device tree bindings
> +
> +maintainer:
> +  - Fengping Yu <fengping.yu@mediatek.com>
> +
> +description: |
> +  Mediatek's Keypad controller is used to interface a SoC with a matrix-type
> +  keypad device. The keypad controller supports multiple row and column lines.
> +  A key can be placed at each intersection of a unique row and a unique column.
> +  The keypad controller can sense a key-press and key-release and report the
> +  event using a interrupt to the cpu.
> +
> +properties:
> +  compatible:
> +    oneOf:
> +      - const: "mediatek,mt6779-keypad"
> +      - const: "mediatek,mt6873-keypad"
> +
> +  clock-names:
> +    description: Names of the clocks listed in clocks property in the same order
> +    maxItems: 1

Please list the clock-names required. In this case, 'kpd'


> +
> +  clocks:
> +    description: Must contain one entry, for the module clock
> +    refs: devicetree/bindings/clocks/clock-bindings.txt for details.
> +
> +  interrupts:
> +    description: A single interrupt specifier
> +    maxItems: 1
> +
> +  linux,keymap:
> +    description: The keymap for keys as described in the binding document
> +    refs: devicetree/bindings/input/matrix-keymap.txt
> +    minItems: 1
> +    maxItems: 16

Why is this max at 16?


> +
> +  pinctrl-0:
> +    description: Specify pin control groups used for this controller
> +    refs: devicetree/bindings/pinctrl/pinctrl-bindings.txt
> +
> +  pinctrl-names:
> +    description: Names for optional pin modes
> +    maxItems: 1

I'm not sure we should list pinctrl here. 


> +
> +  reg:
> +    description: The base address of the Keypad register bank
> +    maxItems: 1
> +
> +  wakeup-source:
> +    description: use any event on keypad as wakeup event
> +    type: boolean
> +
> +  keypad,num-columns:
> +    description: Number of column lines connected to the keypad controller,
> +    it is not equal to PCB columns number, instead you should add required value
> +    for each IC
> +
> +  keypad,num-rows:
> +    description: Number of row lines connected to the keypad controller, it is
> +    not equal to PCB rows number, instead you should add required value for each IC

So the values depend on IC HW. These are not listed as required. Can
your driver works without them? Default value?

> +
> +  mediatek,debounce-us:
> +    description: Debounce interval in microseconds, if not specified, the default
> +    value is 16000
> +    maximum: 256000
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - linux,keymap
> +  - pinctrl
> +  - clocks
> +  - clock-names
> +
> +examples:
> +  - |
> +
> +  keypad: kp@10010000 {

This should be 'keypad' or instead of kp.

Joe.C

> +    compatible = "mediatek,mt6779-keypad";
> +    reg = <0 0x10010000 0 0x1000>;
> +    linux,keymap = < MATRIX_KEY(0x00, 0x00, KEY_VOLUMEDOWN) >;
> +    interrupts = <GIC_SPI 75 IRQ_TYPE_EDGE_FALLING>;
> +    clocks = <&clk26m>;
> +    clock-names = "kpd";
> +    pinctrl-names = "default";
> +    pinctrl-0 = <&kpd_gpios_def_cfg>;
> +  };