[v2,3/3] input/touchscreen: imagis: Add supports for Imagis IST3038

  From: Markuss Broks <markuss.broks@gmail.com>

Imagis IST3038 is another variant of Imagis IST3038 IC, which has
a different register interface from IST3038C (possibly firmware defined).

This should also work for IST3044B (though untested), however other
variants using this interface/protocol(IST3026, IST3032, IST3026B,
IST3032B) have a different format for coordinates, and they'd need
additional effort to be supported by this driver.

Signed-off-by: Markuss Broks <markuss.broks@gmail.com>
[Use IST3038C_REG_CHIPID_BASE]
Signed-off-by: Lin, Meng-Bo <linmengbo0689@protonmail.com>
---
 drivers/input/touchscreen/imagis.c | 62 ++++++++++++++++++++++++------
 1 file changed, 51 insertions(+), 11 deletions(-)
  

On Fri, Nov 18, 2022 at 18:21, "Lin, Meng-Bo" <linmengbo0689@protonmail.com> wrote:

> From: Markuss Broks <markuss.broks@gmail.com>
>
> Imagis IST3038 is another variant of Imagis IST3038 IC, which has
> a different register interface from IST3038C (possibly firmware defined).
>
> This should also work for IST3044B (though untested), however other
> variants using this interface/protocol(IST3026, IST3032, IST3026B,
> IST3032B) have a different format for coordinates, and they'd need
> additional effort to be supported by this driver.
>
> Signed-off-by: Markuss Broks <markuss.broks@gmail.com>
> [Use IST3038C_REG_CHIPID_BASE]
> Signed-off-by: Lin, Meng-Bo <linmengbo0689@protonmail.com>

Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>

> ---
>  drivers/input/touchscreen/imagis.c | 62 ++++++++++++++++++++++++------
>  1 file changed, 51 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/input/touchscreen/imagis.c b/drivers/input/touchscreen/imagis.c
> index b667914a44f1..eb3b0684817f 100644
> --- a/drivers/input/touchscreen/imagis.c
> +++ b/drivers/input/touchscreen/imagis.c
> @@ -13,7 +13,8 @@
>  
>  #define IST3038C_HIB_ACCESS		(0x800B << 16)
>  #define IST3038C_DIRECT_ACCESS		BIT(31)
> -#define IST3038C_REG_CHIPID		0x40001000
> +#define IST3038C_REG_CHIPID_BASE	0x40001000
> +#define IST3038C_REG_CHIPID(base)	(base | IST3038C_DIRECT_ACCESS)
>  #define IST3038C_REG_HIB_BASE		0x30000100
>  #define IST3038C_REG_TOUCH_STATUS	(IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS)
>  #define IST3038C_REG_TOUCH_COORD	(IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS | 0x8)
> @@ -31,8 +32,24 @@
>  #define IST3038C_FINGER_COUNT_SHIFT	12
>  #define IST3038C_FINGER_STATUS_MASK	GENMASK(9, 0)
>  
> +#define IST30XX_REG_STATUS		0x20
> +#define IST30XXB_REG_CHIPID_BASE	0x40000000
> +#define IST30XX_WHOAMI			0x30003000
> +#define IST30XXA_WHOAMI			0x300a300a
> +#define IST30XXB_WHOAMI			0x300b300b
> +#define IST3038_WHOAMI			0x30383038
> +
> +struct imagis_properties {
> +	unsigned int interrupt_msg_cmd;
> +	unsigned int touch_coord_cmd;
> +	unsigned int chipid_base;
> +	unsigned int whoami_val;
> +	bool protocol_b;
> +};
> +
>  struct imagis_ts {
>  	struct i2c_client *client;
> +	const struct imagis_properties *tdata;
>  	struct input_dev *input_dev;
>  	struct touchscreen_properties prop;
>  	struct regulator_bulk_data supplies[2];
> @@ -84,8 +101,7 @@ static irqreturn_t imagis_interrupt(int irq, void *dev_id)
>  	int i;
>  	int error;
>  
> -	error = imagis_i2c_read_reg(ts, IST3038C_REG_INTR_MESSAGE,
> -				    &intr_message);
> +	error = imagis_i2c_read_reg(ts, ts->tdata->interrupt_msg_cmd, &intr_message);
>  	if (error) {
>  		dev_err(&ts->client->dev,
>  			"failed to read the interrupt message: %d\n", error);
> @@ -104,9 +120,13 @@ static irqreturn_t imagis_interrupt(int irq, void *dev_id)
>  	finger_pressed = intr_message & IST3038C_FINGER_STATUS_MASK;
>  
>  	for (i = 0; i < finger_count; i++) {
> -		error = imagis_i2c_read_reg(ts,
> -					    IST3038C_REG_TOUCH_COORD + (i * 4),
> -					    &finger_status);
> +		if (ts->tdata->protocol_b)
> +			error = imagis_i2c_read_reg(ts,
> +						    ts->tdata->touch_coord_cmd, &finger_status);
> +		else
> +			error = imagis_i2c_read_reg(ts,
> +						    ts->tdata->touch_coord_cmd + (i * 4),
> +						    &finger_status);
>  		if (error) {
>  			dev_err(&ts->client->dev,
>  				"failed to read coordinates for finger %d: %d\n",
> @@ -261,6 +281,12 @@ static int imagis_probe(struct i2c_client *i2c)
>  
>  	ts->client = i2c;
>  
> +	ts->tdata = device_get_match_data(dev);
> +	if (!ts->tdata) {
> +		dev_err(dev, "missing chip data\n");
> +		return -EINVAL;
> +	}
> +
>  	error = imagis_init_regulators(ts);
>  	if (error) {
>  		dev_err(dev, "regulator init error: %d\n", error);
> @@ -279,15 +305,13 @@ static int imagis_probe(struct i2c_client *i2c)
>  		return error;
>  	}
>  
> -	error = imagis_i2c_read_reg(ts,
> -			IST3038C_REG_CHIPID | IST3038C_DIRECT_ACCESS,
> -			&chip_id);
> +	error = imagis_i2c_read_reg(ts, IST3038C_REG_CHIPID(ts->tdata->chipid_base), &chip_id);
>  	if (error) {
>  		dev_err(dev, "chip ID read failure: %d\n", error);
>  		return error;
>  	}
>  
> -	if (chip_id != IST3038C_WHOAMI) {
> +	if (chip_id != ts->tdata->whoami_val) {
>  		dev_err(dev, "unknown chip ID: 0x%x\n", chip_id);
>  		return -EINVAL;
>  	}
> @@ -343,9 +367,25 @@ static int __maybe_unused imagis_resume(struct device *dev)
>  
>  static SIMPLE_DEV_PM_OPS(imagis_pm_ops, imagis_suspend, imagis_resume);
>  
> +static const struct imagis_properties imagis_3038_data = {
> +	.interrupt_msg_cmd = IST30XX_REG_STATUS,
> +	.touch_coord_cmd = IST30XX_REG_STATUS,
> +	.chipid_base = IST30XXB_REG_CHIPID_BASE,
> +	.whoami_val = IST3038_WHOAMI,
> +	.protocol_b = true,
> +};
> +
> +static const struct imagis_properties imagis_3038c_data = {
> +	.interrupt_msg_cmd = IST3038C_REG_INTR_MESSAGE,
> +	.touch_coord_cmd = IST3038C_REG_TOUCH_COORD,
> +	.chipid_base = IST3038C_REG_CHIPID_BASE,
> +	.whoami_val = IST3038C_WHOAMI,
> +};
> +
>  #ifdef CONFIG_OF
>  static const struct of_device_id imagis_of_match[] = {
> -	{ .compatible = "imagis,ist3038c", },
> +	{ .compatible = "imagis,ist3038", .data = &imagis_3038_data },
> +	{ .compatible = "imagis,ist3038c", .data = &imagis_3038c_data },
>  	{ },
>  };
>  MODULE_DEVICE_TABLE(of, imagis_of_match);
> -- 
> 2.30.2