Re: [PATCH V3 2/2] drivers: input: keyboard: add mtk keypad driver

[Yingjoe Chen <yingjoe.chen@mediatek.com>]

Fengpin,

Please address all comments in previous review, either change your code
or explain why you think it is better to keep it as-is.



On Tue, 2020-01-14 at 20:27 +0800, fengping.yu wrote:
> Signed-off-by: fengping.yu <fengping.yu@mediatek.com>
> 
> Add matrix keypad driver for MTK SoC.
> 
> ---
>  arch/arm64/configs/defconfig     |   1 +
>  drivers/input/keyboard/Kconfig   |   8 +
>  drivers/input/keyboard/Makefile  |   1 +
>  drivers/input/keyboard/mtk-kpd.c | 280 +++++++++++++++++++++++++++++++
>  4 files changed, 290 insertions(+)
>  create mode 100644 drivers/input/keyboard/mtk-kpd.c
> 
> 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

Please put defconfig to another 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"

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.


> +	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..e36461c9dd89
> --- /dev/null
> +++ b/drivers/input/keyboard/mtk-kpd.c
> @@ -0,0 +1,280 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2019 MediaTek Inc.
> + * Author Terry Chang <terry.chang@mediatek.com>
> + */
> +#include <linux/clk.h>
> +#include <linux/fs.h>
> +#include <linux/gpio.h>
> +#include <linux/init.h>
> +#include <linux/input/matrix_keypad.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/pinctrl/consumer.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>

why do we need regmap.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		BIT(10)
> +#define KP_COL1_SEL		BIT(11)
> +#define KP_COL2_SEL		BIT(12)

Not used in code, please remove.


> +
> +#define KPD_DEBOUNCE_MASK	GENMASK_ULL(13, 0)
> +
> +#define KPD_NUM_MEMS	5
> +#define KPD_MEM5_BITS	8
> +#define KPD_NUM_KEYS	72	/* 4 * 16 + KPD_MEM5_BITS */

these are no longer used. Please remove.


> +
> +struct mtk_keypad {
> +	struct input_dev *input_dev;
> +	struct clk *clk;
> +	void __iomem *base;
> +	unsigned int irqnr;
> +	bool wakeup;
> +	u32 key_debounce;
> +	u32 n_rows;
> +	u32 n_cols;
> +	u32 keymap_state[KPD_NUM_MEMS];
> +};
> +
> +static void kpd_get_keymap_state(void __iomem *kp_base, u32 state[])
> +{
> +	memset_io(state, 0xff, KPD_NUM_MEMS);
> +	memcpy_fromio(state, kp_base, KPD_NUM_MEMS);
> +}
> +
> +static irqreturn_t kpd_irq_handler(int irq, void *dev_id)
> +{
> +	/* use _nosync to avoid deadlock */
> +	struct mtk_keypad *keypad = dev_id;
> +	unsigned short *keycode = keypad->input_dev->keycode;
> +	u32 new_state[KPD_NUM_MEMS], mask;
> +	unsigned long change = 0;
> +	int bit_nr;
> +	int pressed;
> +	u32 row_shift = get_count_order(keypad->n_cols);
> +	unsigned short code;
> +	int i;
> +
> +	disable_irq_nosync(keypad->irqnr);
> +
> +	kpd_get_keymap_state(keypad->base, new_state);
> +
> +	for (i = 0; i < KPD_NUM_MEMS; i++) {
> +		change = new_state[i] ^ keypad->keymap_state[i];
> +		if (!change)
> +			continue;
> +
> +		for_each_set_bit(bit_nr, &change, 32) {
> +			mask = 1 << bit_nr;
> +			pressed = (new_state[i] & mask) == 0U;
> +			dev_dbg(&keypad->input_dev->dev,
> +				"%s", pressed ? "pressed" : "released");
> +
> +			code = keycode[MATRIX_SCAN_CODE(i, bit_nr, row_shift)];

Although the register is 32bits wide, KP_MEM* only have 16bits data,
after changing to bit array & memcpy_fromio, you need to skip the extra
16bits in each register to get correct row/col counting.

MATRX_SCAN_CODE use row/col, using i & bit_nr doesn't looks right.

> +
> +			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);
> +		}
> +	}
> +
> +	memcpy(keypad->keymap_state, new_state, sizeof(new_state));
> +
> +	enable_irq(keypad->irqnr);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int kpd_get_dts_info(struct mtk_keypad *keypad)
> +{
> +	int ret;
> +	struct device *dev = keypad->input_dev->dev.parent;
> +	struct device_node *node = dev->of_node;
> +
> +	ret = matrix_keypad_parse_properties(dev, &keypad->n_rows,
> +					     &keypad->n_cols);
> +
> +	if (ret) {
> +		dev_err(dev, "failed to parse keypad params.\n");
> +		return ret;
> +	}
> +
> +	ret = of_property_read_u32(node, "mediatek,debounce-us",
> +				   &keypad->key_debounce);

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

> +	if (ret) {
> +		pr_debug("read mediatek,debounce-us error.\n");
> +		return ret;
> +	}
> +
> +	keypad->wakeup = of_property_read_bool(node, "wakeup-source");
> +
> +	dev_dbg(dev, "n_row=%d n_col=%d debounce=%d.\n",
> +		keypad->n_rows, keypad->n_cols,
> +		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)) {
> +		dev_err(dev, "Cannot find keypad_pinctrl!\n");
> +
> +		return PTR_ERR(keypad_pinctrl);
> +	}
> +
> +	kpd_default = pinctrl_lookup_state(keypad_pinctrl, "default");
> +	if (IS_ERR(kpd_default)) {
> +		dev_err(dev, "Cannot find ecall_state!\n");
> +
> +		return 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 err;
> +
> +	if (!pdev->dev.of_node) {
> +		dev_err(&pdev->dev, "No device tree data present.\n");
> +		return -EINVAL;
> +	}
> +
> +	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
> +	if (!keypad)
> +		return -ENOMEM;
> +
> +	memset(keypad->keymap_state, 0xff, sizeof(keypad->keymap_state));
> +
> +	keypad->input_dev = devm_input_allocate_device(&pdev->dev);
> +	if (!keypad->input_dev) {
> +		dev_err(&pdev->dev, "input allocate device fail.\n");
> +		return -ENOMEM;
> +	}
> +
> +	keypad->input_dev->name = KPD_NAME;
> +	keypad->input_dev->id.bustype = BUS_HOST;
> +	keypad->input_dev->dev.parent = &pdev->dev;
> +
> +	err = kpd_get_dts_info(keypad);
> +	if (err) {
> +		dev_err(&pdev->dev, "get dts info failed.\n");
> +		return err;
> +	}
> +
> +	err = matrix_keypad_build_keymap(NULL, NULL,
> +					keypad->n_rows,
> +					keypad->n_cols,
> +					NULL,
> +					keypad->input_dev);
> +
> +	if (err) {
> +		dev_err(&pdev->dev, "build keymap failed.\n");
> +		return err;
> +	}
> +
> +	input_set_drvdata(keypad->input_dev, keypad);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev, "get IO memory resource failed.\n");
> +		return -ENODEV;
> +	}
> +
> +	keypad->base = devm_ioremap_resource(&pdev->dev, res);

please use devm_platform_ioremap_resource instead of using
platform_get_resource+devm_ioremap

Joe.C

> +	if (IS_ERR(keypad->base)) {
> +		dev_err(&pdev->dev, "KP iomap failed\n");
> +		return PTR_ERR(keypad->base);
> +	}
> +
> +	writew((keypad->key_debounce * 32 / 1000 & KPD_DEBOUNCE_MASK),
> +		keypad->base + KP_DEBOUNCE);
> +
> +	keypad->clk = devm_clk_get(&pdev->dev, "kpd");
> +	if (IS_ERR(keypad->clk)) {
> +		dev_err(&pdev->dev, "get kpd-clk fail.\n");
> +		return PTR_ERR(keypad->clk);
> +	}
> +
> +	err = clk_prepare_enable(keypad->clk);
> +	if (err) {
> +		dev_err(&pdev->dev, "kpd-clk prepare enable failed.\n");
> +		return err;
> +	}
> +
> +	err = kpd_gpio_init(&pdev->dev);
> +	if (err) {
> +		dev_err(&pdev->dev, "gpio init failed\n");
> +		return err;
> +	}
> +
> +	keypad->irqnr = platform_get_irq(pdev, 0);
> +	if (!keypad->irqnr) {
> +		dev_err(&pdev->dev, "KP get irqnr failed\n");
> +		return -EINVAL;
> +	}
> +
> +	err = devm_request_irq(&pdev->dev, keypad->irqnr,
> +				kpd_irq_handler, 0,
> +				KPD_NAME, keypad);
> +	if (err) {
> +		dev_err(&pdev->dev, "register IRQ failed.\n");
> +		return err;
> +	}
> +
> +	err = input_register_device(keypad->input_dev);
> +	if (err) {
> +		dev_err(&pdev->dev, "register input device failed.\n");
> +		return err;
> +	}
> +
> +	device_init_wakeup(&pdev->dev, keypad->wakeup);
> +
> +	platform_set_drvdata(pdev, keypad);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id kpd_of_match[] = {
> +	{.compatible = "mediatek,kp"},
> +	{}
> +};
> +
> +static struct platform_driver kpd_pdrv = {
> +	.probe = kpd_pdrv_probe,
> +	.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");

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