Re: [PATCH v5 2/2] Input: msg2638 - Add support for msg2138 key events

Dmitry Torokhov
2022-11-16T20:33:57Z

On Wed, Nov 16, 2022 at 07:17:12PM +0100, Vincent Knecht wrote:
> Some devices with msg2138 have back/menu/home keys.
> Add support for them.
>
> Signed-off-by: Vincent Knecht <vincent.knecht@mailoo.org>
> ---
> drivers/input/touchscreen/msg2638.c | 57 +++++++++++++++++++++++++++--
> 1 file changed, 53 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/input/touchscreen/msg2638.c b/drivers/input/touchscreen/msg2638.c
> index 95b18563326a..a0f5e1ecd612 100644
> --- a/drivers/input/touchscreen/msg2638.c
> +++ b/drivers/input/touchscreen/msg2638.c
> @@ -21,6 +21,7 @@
> #include <linux/kernel.h>
> #include <linux/mod_devicetable.h>
> #include <linux/module.h>
> +#include <linux/property.h>
> #include <linux/regulator/consumer.h>
> #include <linux/slab.h>
>
> @@ -29,6 +30,8 @@
> #define MSG2138_MAX_FINGERS 2
> #define MSG2638_MAX_FINGERS 5
>
> +#define MAX_BUTTONS 4
> +
> #define CHIP_ON_DELAY_MS 15
> #define FIRMWARE_ON_DELAY_MS 50
> #define RESET_DELAY_MIN_US 10000
> @@ -72,6 +75,8 @@ struct msg2638_ts_data {
> struct regulator_bulk_data supplies[2];
> struct gpio_desc *reset_gpiod;
> int max_fingers;
> + u32 keycodes[MAX_BUTTONS];
> + int num_keycodes;
> };
>
> static u8 msg2638_checksum(u8 *data, u32 length)
> @@ -85,6 +90,18 @@ static u8 msg2638_checksum(u8 *data, u32 length)
> return (u8)((-sum) & 0xFF);
> }
>
> +static void msg2138_report_keys(struct msg2638_ts_data *msg2638, u8 keys)
> +{
> + int i;
> +
> + /* keys can be 0x00 or 0xff when all keys have been released */
> + if (keys == 0xff)
> + keys = 0;
> +
> + for (i = 0; i < msg2638->num_keycodes; ++i)
> + input_report_key(msg2638->input_dev, msg2638->keycodes[i], keys & BIT(i));
> +}
> +
> static irqreturn_t msg2138_ts_irq_handler(int irq, void *msg2638_handler)
> {
> struct msg2638_ts_data *msg2638 = msg2638_handler;
> @@ -121,9 +138,12 @@ static irqreturn_t msg2138_ts_irq_handler(int irq, void *msg2638_handler)
> p0 = &touch_event.pkt[0];
> p1 = &touch_event.pkt[1];
>
> - /* Ignore non-pressed finger data */
> - if (p0->xy_hi == 0xFF && p0->x_low == 0xFF && p0->y_low == 0xFF)
> + /* Ignore non-pressed finger data, but check for key code */
> + if (p0->xy_hi == 0xFF && p0->x_low == 0xFF && p0->y_low == 0xFF) {
> + if (p1->xy_hi == 0xFF && p1->y_low == 0xFF)
> + msg2138_report_keys(msg2638, p1->x_low);
> goto report;
> + }
>
> x = ((p0->xy_hi & 0xF0) << 4) | p0->x_low;
> y = ((p0->xy_hi & 0x0F) << 8) | p0->y_low;
> @@ -283,6 +303,7 @@ static int msg2638_init_input_dev(struct msg2638_ts_data *msg2638)
> struct device *dev = &msg2638->client->dev;
> struct input_dev *input_dev;
> int error;
> + int i;
>
> input_dev = devm_input_allocate_device(dev);
> if (!input_dev) {
> @@ -299,6 +320,14 @@ static int msg2638_init_input_dev(struct msg2638_ts_data *msg2638)
> input_dev->open = msg2638_input_open;
> input_dev->close = msg2638_input_close;
>
> + if (msg2638->num_keycodes) {
> + input_dev->keycode = msg2638->keycodes;
> + input_dev->keycodemax = msg2638->num_keycodes;
> + input_dev->keycodesize = sizeof(msg2638->keycodes[0]);
> + for (i = 0; i < msg2638->num_keycodes; i++)
> + input_set_capability(input_dev, EV_KEY, msg2638->keycodes[i]);
> + }
> +
> input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X);
> input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y);
>
> @@ -367,9 +396,23 @@ static int msg2638_ts_probe(struct i2c_client *client)
> return error;
> }
>
> - error = msg2638_init_input_dev(msg2638);
> + msg2638->num_keycodes = fwnode_property_count_u32(dev->fwnode, "linux,keycodes");

Please use device_property_count_u32().

> + if (msg2638->num_keycodes == -EINVAL) {
> + msg2638->num_keycodes = 0;
> + } else if (msg2638->num_keycodes < 0) {
> + dev_err(dev, "Unable to parse linux,keycodes property: %d\n",
> + msg2638->num_keycodes);
> + return msg2638->num_keycodes;
> + } else if (msg2638->num_keycodes > ARRAY_SIZE(msg2638->keycodes)) {
> + dev_warn(dev, "Found %d linux,keycodes but max is %ld, ignoring the rest\n",
> + msg2638->num_keycodes, ARRAY_SIZE(msg2638->keycodes));

I think you want "%zd" in place of "%ld".

> + msg2638->num_keycodes = ARRAY_SIZE(msg2638->keycodes);
> + }
> +
> + error = fwnode_property_read_u32_array(dev->fwnode, "linux,keycodes",
> + msg2638->keycodes, msg2638->num_keycodes);

Please use device_property_read_u32_array().

> if (error) {
> - dev_err(dev, "Failed to initialize input device: %d\n", error);
> + dev_err(dev, "Unable to read linux,keycodes values: %d\n", error);
> return error;
> }
>
> @@ -382,6 +425,12 @@ static int msg2638_ts_probe(struct i2c_client *client)
> return error;
> }
>
> + error = msg2638_init_input_dev(msg2638);
> + if (error) {
> + dev_err(dev, "Failed to initialize input device: %d\n", error);
> + return error;
> + }
> +
> return 0;
> }
>
> --
> 2.38.1
>
>
>

Thanks.

--
Dmitry