Hi Joel,
On 5/27/24 5:26 AM, Joel Selvaraj via B4 Relay wrote:
> From: Joel Selvaraj <joelselvaraj.oss@xxxxxxxxx>
>
> Extend the novatek touchscreen driver to support NT36672A chip which
> is found in phones like qcom/sdm845-xiaomi-beryllium-tianma.dts.
> Added devicetree support for the driver and used i2c chip data to handle
> the variation in chip id and wake type. Also added vcc and iovcc
> regulators which are used to power the touchscreen hardware.
>
> Signed-off-by: Joel Selvaraj <joelselvaraj.oss@xxxxxxxxx>
> ---
> drivers/input/touchscreen/novatek-nvt-ts.c | 78 +++++++++++++++++++++++++++---
> 1 file changed, 72 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/input/touchscreen/novatek-nvt-ts.c b/drivers/input/touchscreen/novatek-nvt-ts.c
> index 224fd112b25a9..7a82a1b09f9d5 100644
> --- a/drivers/input/touchscreen/novatek-nvt-ts.c
> +++ b/drivers/input/touchscreen/novatek-nvt-ts.c
> @@ -31,9 +31,6 @@
> #define NVT_TS_PARAMS_CHIP_ID 0x0e
> #define NVT_TS_PARAMS_SIZE 0x0f
>
> -#define NVT_TS_SUPPORTED_WAKE_TYPE 0x05
> -#define NVT_TS_SUPPORTED_CHIP_ID 0x05
> -
> #define NVT_TS_MAX_TOUCHES 10
> #define NVT_TS_MAX_SIZE 4096
>
> @@ -51,11 +48,18 @@ static const int nvt_ts_irq_type[4] = {
> IRQF_TRIGGER_HIGH
> };
>
> +struct nvt_ts_i2c_chip_data {
> + u8 wake_type;
> + u8 chip_id;
> +};
> +
> struct nvt_ts_data {
> struct i2c_client *client;
> struct input_dev *input;
> struct gpio_desc *reset_gpio;
> + struct regulator_bulk_data regulators[2];
> struct touchscreen_properties prop;
> + const struct nvt_ts_i2c_chip_data *chip;
> int max_touches;
> u8 buf[NVT_TS_TOUCH_SIZE * NVT_TS_MAX_TOUCHES];
> };
> @@ -139,9 +143,23 @@ static irqreturn_t nvt_ts_irq(int irq, void *dev_id)
> return IRQ_HANDLED;
> }
>
> +static void nvt_ts_disable_regulators(void *_data)
> +{
> + struct nvt_ts_data *data = _data;
> +
> + regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
> +}
> +
> static int nvt_ts_start(struct input_dev *dev)
> {
> struct nvt_ts_data *data = input_get_drvdata(dev);
> + int error;
> +
> + error = regulator_bulk_enable(ARRAY_SIZE(data->regulators), data->regulators);
> + if (error) {
> + dev_err(&data->client->dev, "failed to enable regulators\n");
> + return error;
> + }
>
This is weird, you already enable the regulators in probe() and
those get disabled again on remove() by the devm action you add.
So there is no need to enable / disable the regulators on start/stop .
If you want the regulators to only be enabled when the touchscreen
is on then you should disable the regulators again in probe()
after the nvt_ts_read_data() call there (and drop the devm action).
Or if you want to leave the regulators on all the time then you can
drop the enable + disable calls here.
> enable_irq(data->client->irq);
> gpiod_set_value_cansleep(data->reset_gpio, 0);
> @@ -155,6 +173,7 @@ static void nvt_ts_stop(struct input_dev *dev)
>
> disable_irq(data->client->irq);
> gpiod_set_value_cansleep(data->reset_gpio, 1);
> + nvt_ts_disable_regulators(data);
> }
>
> static int nvt_ts_suspend(struct device *dev)
> @@ -199,9 +218,37 @@ static int nvt_ts_probe(struct i2c_client *client)
> if (!data)
> return -ENOMEM;
>
> + data->chip = device_get_match_data(&client->dev);
> + if (!data->chip)
> + return -EINVAL;
> +
> data->client = client;
> i2c_set_clientdata(client, data);
>
> + /*
> + * VCC is the analog voltage supply
> + * IOVCC is the digital voltage supply
> + */
> + data->regulators[0].supply = "vcc";
> + data->regulators[1].supply = "iovcc";
> + error = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators), data->regulators);
> + if (error) {
> + dev_err(dev, "cannot get regulators: %d\n", error);
> + return error;
> + }
> +
> + error = regulator_bulk_enable(ARRAY_SIZE(data->regulators), data->regulators);
> + if (error) {
> + dev_err(dev, "failed to enable regulators\n");
> + return error;
> + }
> +
> + error = devm_add_action_or_reset(dev, nvt_ts_disable_regulators, data);
> + if (error) {
> + dev_err(dev, "failed to install regulator disable handler\n");
> + return error;
> + }
> +
If you are going to keep this devm action (see discussion above) then please
switch from devm_regulator_bulk_get() + regulator_bulk_enable() to
devm_regulator_bulk_get_enable() which gets and enables the regulators for
you in one call.
You can then drop the regulator_bulk_enable() + devm_add_action_or_reset()
calls since devm_regulator_bulk_get_enable() takes care of both for you.
> data->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
> error = PTR_ERR_OR_ZERO(data->reset_gpio);
> if (error) {
> @@ -225,8 +272,8 @@ static int nvt_ts_probe(struct i2c_client *client)
> if (width > NVT_TS_MAX_SIZE || height >= NVT_TS_MAX_SIZE ||
> data->max_touches > NVT_TS_MAX_TOUCHES ||
> irq_type >= ARRAY_SIZE(nvt_ts_irq_type) ||
> - data->buf[NVT_TS_PARAMS_WAKE_TYPE] != NVT_TS_SUPPORTED_WAKE_TYPE ||
> - data->buf[NVT_TS_PARAMS_CHIP_ID] != NVT_TS_SUPPORTED_CHIP_ID) {
> + data->buf[NVT_TS_PARAMS_WAKE_TYPE] != data->chip->wake_type ||
> + data->buf[NVT_TS_PARAMS_CHIP_ID] != data->chip->chip_id) {
> dev_err(dev, "Unsupported touchscreen parameters: %*ph\n",
> NVT_TS_PARAMS_SIZE, data->buf);
> return -EIO;
> @@ -277,8 +324,26 @@ static int nvt_ts_probe(struct i2c_client *client)
> return 0;
> }
>
> +static const struct nvt_ts_i2c_chip_data nvt_nt11205_ts_data = {
> + .wake_type = 0x05,
> + .chip_id = 0x05,
> +};
> +
> +static const struct nvt_ts_i2c_chip_data nvt_nt36672a_ts_data = {
> + .wake_type = 0x01,
> + .chip_id = 0x08,
> +};
> +
> +static const struct of_device_id nvt_ts_of_match[] = {
> + { .compatible = "novatek,nt11205-ts", .data = &nvt_nt11205_ts_data },
> + { .compatible = "novatek,nt36672a-ts", .data = &nvt_nt36672a_ts_data },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, nvt_ts_of_match);
> +
> static const struct i2c_device_id nvt_ts_i2c_id[] = {
> - { "NT11205-ts" },
> + { "NT11205-ts", (unsigned long) &nvt_nt11205_ts_data },
> + { "NT36672A-ts", (unsigned long) &nvt_nt36672a_ts_data },
The i2c-subsystem will also match of compatible strings to i2c_device_ids
by looking at the partof the compatible after the ',', so for a compatible
of e.g. "novatek,nt36672a-ts" will match an i2c_device_id of "nt36672a-ts".
So if you change these to lower-case:
{ "nt11205-ts", (unsigned long) &nvt_nt11205_ts_data },
{ "nt36672a-ts", (unsigned long) &nvt_nt36672a_ts_data },
Then you can drop the nvt_ts_of_match table since that is not necessary
then.
Hmm I just realized that this will break module auto-loading though since that
does require of modaliases .
So maybe this is not such a good idea after all. Still switching to lowercase
i2c_device_id-s would be good for consistency and you need to respin
the patch-set for the regulator issue anyways.
Regards,
Hans
> { }
> };
> MODULE_DEVICE_TABLE(i2c, nvt_ts_i2c_id);
> @@ -287,6 +352,7 @@ static struct i2c_driver nvt_ts_driver = {
> .driver = {
> .name = "novatek-nvt-ts",
> .pm = pm_sleep_ptr(&nvt_ts_pm_ops),
> + .of_match_table = nvt_ts_of_match,
> },
> .probe = nvt_ts_probe,
> .id_table = nvt_ts_i2c_id,
>
