Hi Joel,
Thank you for the new version.
On 6/1/24 5:30 PM, 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 | 70 +++++++++++++++++++++++++++---
1 file changed, 64 insertions(+), 6 deletions(-)
diff --git a/drivers/input/touchscreen/novatek-nvt-ts.c b/drivers/input/touchscreen/novatek-nvt-ts.c
index 9bee3a0c122fb..c24c33f609eb8 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;
Almost there. I have one remark which requires fixing below,
so since a v5 will be necessary anyways I also spotted another
small possible improvement:
Since you only use chip->wake_type and chip->chip_id
inside probe() you can make this chip pointer a local
variable in probe(). This saves having this stored
on the kernel heap even though it is never used again.
int max_touches;
u8 buf[NVT_TS_TOUCH_SIZE * NVT_TS_MAX_TOUCHES];
};
@@ -142,6 +146,13 @@ static irqreturn_t nvt_ts_irq(int irq, void *dev_id)
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;
+ }
enable_irq(data->client->irq);
gpiod_set_value_cansleep(data->reset_gpio, 0);
@@ -155,6 +166,7 @@ static void nvt_ts_stop(struct input_dev *dev)
disable_irq(data->client->irq);
gpiod_set_value_cansleep(data->reset_gpio, 1);
+ regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
}
static int nvt_ts_suspend(struct device *dev)
@@ -199,9 +211,31 @@ 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;
+
As mentioned above instead of data->chip you can use a local
"chip" variable here.
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: %d\n", error);
+ return error;
+ }
+
data->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
error = PTR_ERR_OR_ZERO(data->reset_gpio);
if (error) {
Almost there. You need to disable the regulators when probe fails to
avoid an error from the regulator core about unbalanced enable/disable
of the regulators when the devm framework releases them.
So you need to add a regulator_bulk_disable() call in
the "if (error) {" branch here:
data->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
error = PTR_ERR_OR_ZERO(data->reset_gpio);
if (error) {
regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
dev_err(dev, "failed to request reset GPIO: %d\n", error);
return error;
}
And ... (continued below)
@@ -216,6 +250,11 @@ static int nvt_ts_probe(struct i2c_client *client)
gpiod_set_value_cansleep(data->reset_gpio, 1); /* Put back in reset */
if (error)
return error;
+ error = regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
I would not error check this, just like how it is not error checked
in void nvt_ts_stop() and then I would move it to above the error
checking for the nvt_ts_read_data(...NVT_TS_PARAMETERS...), to avoid
the need for an extra regulator_bulk_disable() call in the if (error)
path for the nvt_ts_read_data() call.
So make the code look like this:
error = nvt_ts_read_data(data->client, NVT_TS_PARAMETERS_START,
data->buf, NVT_TS_PARAMS_SIZE);
gpiod_set_value_cansleep(data->reset_gpio, 1); /* Put back in reset */
regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
if (error)
return error;
width = get_unaligned_be16(&data->buf[NVT_TS_PARAMS_WIDTH]);
height = get_unaligned_be16(&data->buf[NVT_TS_PARAMS_HEIGHT]);
...
This way you only need one extra regulator_bulk_disable() call for
error-exit paths in the case of devm_gpiod_get(dev, "reset", ...)
failing.
Regards,
Hans
@@ -225,8 +264,8 @@ 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 +316,26 @@ 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 },
{ }
};
MODULE_DEVICE_TABLE(i2c, nvt_ts_i2c_id);
@@ -287,6 +344,7 @@ 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,
