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

Andy Shevchenko
2020-01-14T16:36:15Z

On Tue, Jan 14, 2020 at 08:27:41PM +0800, fengping.yu wrote:
> Signed-off-by: fengping.yu <fengping.yu@mediatek.com>
>
> Add matrix keypad driver for MTK SoC.

Something wrong with ordering.

...

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

TABs / space mix. I think you ignored my comment.

...

> +#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>

...

> +#define KPD_DEBOUNCE_MASK GENMASK_ULL(13, 0)

ULL? Why?

...

> +static void kpd_get_keymap_state(void __iomem *kp_base, u32 state[])

u32 *state

> +{

> + memset_io(state, 0xff, KPD_NUM_MEMS);

This is strange. What is this for and why is it needed?

> + 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;

test_bit() ?

Can't new_state be unsigned long? In this case you may get rid of outer loop I
suppose.

> + dev_dbg(&keypad->input_dev->dev,
> + "%s", pressed ? "pressed" : "released");
> +
> + code = keycode[MATRIX_SCAN_CODE(i, bit_nr, 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);
> + }
> + }
> +
> + 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);

> +

Redundant line.

> + 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);
> + if (ret) {

> + pr_debug("read mediatek,debounce-us error.\n");

dev_dbg() ?

> + 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");

> +

Redundant line

> + 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");

> +

Ditto.

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

...

> + int err;

err or ret? Be consistent with the name of variable that keeps returned code.

> + if (!pdev->dev.of_node) {
> + dev_err(&pdev->dev, "No device tree data present.\n");
> + return -EINVAL;
> + }

I think this is redundant. below calls will fail when property is not found.

> + keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
> + if (!keypad)
> + return -ENOMEM;
> +

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

bitmap_fill() ?

> + err = matrix_keypad_build_keymap(NULL, NULL,
> + keypad->n_rows,
> + keypad->n_cols,
> + NULL,
> + keypad->input_dev);

> + 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);

devm_platform_ioremap_resource()

> + 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),

Useless parentheses. It's not lisp!

> + keypad->base + KP_DEBOUNCE);

> + 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;

Starting from here down the clocks left in a wrong state.

> + }
> +
> + keypad->irqnr = platform_get_irq(pdev, 0);

> + if (!keypad->irqnr) {

This is wrong...

> + dev_err(&pdev->dev, "KP get irqnr failed\n");

> + return -EINVAL;

...and so does this.

> + }

--
With Best Regards,
Andy Shevchenko