Re: [PATCH 2/2] Input: edt-ft5x06: Add DT support

From: Jingoo Han
Date: Tue Jan 14 2014 - 19:46:53 EST

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In reply to: Mark Rutland: "Re: [PATCH 2/2] Input: edt-ft5x06: Add DT support"
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On Monday, January 13, 2014 7:17 PM, Lothar WaÃmann wrote:
>
> This patch allows the edt-ft5x06 multitouch panel driver to be
> configured via DT.
>
> Signed-off-by: Lothar WaÃmann <LW@xxxxxxxxxxxxxxxxxxx>

(+cc Simon Budig)

This 'edt-ft5x06' driver was made by Simon Budig.
Please, add him to CC list.

Also, I added some comments. :-)

> ---
> .../bindings/input/touchscreen/edt-ft5x06.txt | 31 ++++
> drivers/input/touchscreen/edt-ft5x06.c | 145 +++++++++++++++----
> 2 files changed, 145 insertions(+), 31 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt
>
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt
> b/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt
> new file mode 100644
> index 0000000..629dbdd
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt
> @@ -0,0 +1,31 @@
> +* EDT FT5x06 Multiple Touch Controller
> +
> +Required properties:
> +- compatible: must be "edt,ft5x06"
> +- reg: i2c slave address
> +- interrupt-parent: the phandle for the interrupt controller
> +- interrupts: touch controller interrupt
> +
> +Optional properties:
> +- reset-gpios: the gpio pin to be used for resetting the controller
> +- wakeup-gpios: the gpio pin to be used for waking up the controller
> +
> + The following properties provide default values for the
> + corresponding parameters configurable via sysfs
> + (see Documentation/input/edt-ft5x06.txt)
> +- threshold: allows setting the "click"-threshold in the range from 20 to 80.
> +- gain: sensitivity (0..31) (lower value -> higher sensitivity)
> +- offset: edge compensation (0..31)
> +- report_rate: report rate (3..14)

s/report_rate/report-rate

> +
> +Example:
> +
> + edt_ft5x06@38 {
> + compatible = "edt,ft5x06";
> + reg = <0x38>;
> + interrupt-parent = <&gpio2>;
> + interrupts = <5 0>;
> + wakeup-gpios = <&gpio1 9 0>;
> + reset-gpios = <&gpio2 6 1>;
> + wakeup-gpios = <&gpio4 9 0>;
> + };
> diff --git a/drivers/input/touchscreen/edt-ft5x06.c b/drivers/input/touchscreen/edt-ft5x06.c
> index af0d68b..02dce42 100644
> --- a/drivers/input/touchscreen/edt-ft5x06.c
> +++ b/drivers/input/touchscreen/edt-ft5x06.c
> @@ -33,6 +33,7 @@
> #include <linux/debugfs.h>
> #include <linux/slab.h>
> #include <linux/gpio.h>
> +#include <linux/of_gpio.h>
> #include <linux/input/mt.h>
> #include <linux/input/edt-ft5x06.h>
>
> @@ -65,6 +66,10 @@ struct edt_ft5x06_ts_data {
> u16 num_x;
> u16 num_y;
>
> + int reset_pin;
> + int irq_pin;
> + int wake_pin;
> +
> #if defined(CONFIG_DEBUG_FS)
> struct dentry *debug_dir;
> u8 *raw_buffer;
> @@ -617,24 +622,37 @@ edt_ft5x06_ts_teardown_debugfs(struct edt_ft5x06_ts_data *tsdata)
>
>
> static int edt_ft5x06_ts_reset(struct i2c_client *client,
> - int reset_pin)
> + struct edt_ft5x06_ts_data *tsdata)
> {
> int error;
>
> - if (gpio_is_valid(reset_pin)) {
> + if (gpio_is_valid(tsdata->wake_pin)) {
> + error = gpio_request_one(tsdata->wake_pin, GPIOF_OUT_INIT_LOW,
> + "edt-ft5x06 wake");

Please use devm_gpio_request_one(), because it makes the code
simpler.

> + if (error) {
> + dev_err(&client->dev,
> + "Failed to request GPIO %d as wake pin, error %d\n",
> + tsdata->wake_pin, error);
> + return error;
> + }
> +
> + mdelay(5);
> + gpio_set_value(tsdata->wake_pin, 1);
> + }
> + if (gpio_is_valid(tsdata->reset_pin)) {
> /* this pulls reset down, enabling the low active reset */
> - error = gpio_request_one(reset_pin, GPIOF_OUT_INIT_LOW,
> + error = gpio_request_one(tsdata->reset_pin, GPIOF_OUT_INIT_LOW,
> "edt-ft5x06 reset");

Please use devm_gpio_request_one() too.

> if (error) {
> dev_err(&client->dev,
> "Failed to request GPIO %d as reset pin, error %d\n",
> - reset_pin, error);
> + tsdata->reset_pin, error);
> return error;
> }
>
> - mdelay(50);
> - gpio_set_value(reset_pin, 1);
> - mdelay(100);
> + mdelay(5);
> + gpio_set_value(tsdata->reset_pin, 1);
> + mdelay(300);
> }
>
> return 0;
> @@ -674,6 +692,21 @@ static int edt_ft5x06_ts_identify(struct i2c_client *client,
> pdata->name <= edt_ft5x06_attr_##name.limit_high) \
> edt_ft5x06_register_write(tsdata, reg, pdata->name)
>
> +#define EDT_GET_PROP(name, reg) { \
> + const u32 *prop = of_get_property(np, #name, NULL); \
> + if (prop) \
> + edt_ft5x06_register_write(tsdata, reg, be32_to_cpu(*prop)); \
> +}
> +
> +static void edt_ft5x06_ts_get_dt_defaults(struct device_node *np,
> + struct edt_ft5x06_ts_data *tsdata)
> +{
> + EDT_GET_PROP(threshold, WORK_REGISTER_THRESHOLD);
> + EDT_GET_PROP(gain, WORK_REGISTER_GAIN);
> + EDT_GET_PROP(offset, WORK_REGISTER_OFFSET);
> + EDT_GET_PROP(report_rate, WORK_REGISTER_REPORT_RATE);
> +}
> +
> static void
> edt_ft5x06_ts_get_defaults(struct edt_ft5x06_ts_data *tsdata,
> const struct edt_ft5x06_platform_data *pdata)
> @@ -701,6 +734,39 @@ edt_ft5x06_ts_get_parameters(struct edt_ft5x06_ts_data *tsdata)
> tsdata->num_y = edt_ft5x06_register_read(tsdata, WORK_REGISTER_NUM_Y);
> }
>
> +#ifdef CONFIG_OF
> +static int edt_ft5x06_i2c_ts_probe_dt(struct device *dev,
> + struct edt_ft5x06_ts_data *tsdata)
> +{
> + int ret;
> + struct device_node *np = dev->of_node;
> + enum of_gpio_flags gpio_flags;
> +
> + if (!np)
> + return -ENODEV;
> +
> + /*
> + * irq_pin is not needed for DT setup.
> + * irq is associated via 'interrupts' property in DT
> + */
> + tsdata->irq_pin = -EINVAL;
> +
> + ret = of_get_named_gpio_flags(np, "reset-gpios", 0, &gpio_flags);
> + tsdata->reset_pin = ret;

This code looks awkward.
There are two ways, please choose one of them.

1. Check the return value

ret = of_get_named_gpio_flags(np, "reset-gpios", 0, &gpio_flags);
if (ret < 0) {
dev_err(dev, "reset-gpios pin is not provided.\n");
return ret;
}
tsdata->reset_pin = ret;

2. No check the return value, passing it directly

tsdata->reset_pin = of_get_named_gpio_flags(np, "reset-gpios", 0, &gpio_flags);

> +
> + ret = of_get_named_gpio_flags(np, "wake-gpios", 0, &gpio_flags);

According to the Documentation 'edt-ft5x06.txt',
'wakeup-gpios' is used, instead of 'wake-gpios'.
What is the right name?

> + tsdata->wake_pin = ret;
> +
> + return 0;
> +}
> +#else
> +static inline int edt_ft5x06_i2c_ts_probe_dt(struct device *dev,
> + struct edt_ft5x06_i2c_ts_data *tsdata)
> +{
> + return -ENODEV;
> +}
> +#endif
> +
> static int edt_ft5x06_ts_probe(struct i2c_client *client,
> const struct i2c_device_id *id)
> {
> @@ -713,30 +779,43 @@ static int edt_ft5x06_ts_probe(struct i2c_client *client,
>
> dev_dbg(&client->dev, "probing for EDT FT5x06 I2C\n");
>
> + tsdata = devm_kzalloc(&client->dev, sizeof(*tsdata), GFP_KERNEL);
> + if (!tsdata) {
> + dev_err(&client->dev, "failed to allocate driver data.\n");
> + return -ENOMEM;
> + }
> +
> if (!pdata) {
> - dev_err(&client->dev, "no platform data?\n");
> - return -EINVAL;
> + error = edt_ft5x06_i2c_ts_probe_dt(&client->dev, tsdata);
> + if (error) {
> + dev_err(&client->dev,
> + "DT probe failed and no platform data present\n");
> + return error;
> + }
> + } else {
> + tsdata->reset_pin = pdata->reset_pin;
> + tsdata->irq_pin = pdata->irq_pin;
> + tsdata->wake_pin = -EINVAL;
> }
>
> - error = edt_ft5x06_ts_reset(client, pdata->reset_pin);
> + error = edt_ft5x06_ts_reset(client, tsdata);
> if (error)
> return error;
>
> - if (gpio_is_valid(pdata->irq_pin)) {
> - error = gpio_request_one(pdata->irq_pin,
> + if (gpio_is_valid(tsdata->irq_pin)) {
> + error = gpio_request_one(tsdata->irq_pin,
> GPIOF_IN, "edt-ft5x06 irq");

Please use devm_gpio_request_one() too.

> if (error) {
> dev_err(&client->dev,
> "Failed to request GPIO %d, error %d\n",
> - pdata->irq_pin, error);
> + tsdata->irq_pin, error);
> return error;
> }
> }
>
> - tsdata = kzalloc(sizeof(*tsdata), GFP_KERNEL);
> input = input_allocate_device();
> - if (!tsdata || !input) {
> - dev_err(&client->dev, "failed to allocate driver data.\n");
> + if (!input) {
> + dev_err(&client->dev, "failed to allocate input device.\n");
> error = -ENOMEM;
> goto err_free_mem;
> }
> @@ -752,7 +831,11 @@ static int edt_ft5x06_ts_probe(struct i2c_client *client,
> goto err_free_mem;
> }
>
> - edt_ft5x06_ts_get_defaults(tsdata, pdata);
> + if (!pdata)
> + edt_ft5x06_ts_get_dt_defaults(client->dev.of_node, tsdata);
> + else
> + edt_ft5x06_ts_get_defaults(tsdata, pdata);
> +
> edt_ft5x06_ts_get_parameters(tsdata);
>
> dev_dbg(&client->dev,
> @@ -802,8 +885,8 @@ static int edt_ft5x06_ts_probe(struct i2c_client *client,
> device_init_wakeup(&client->dev, 1);
>
> dev_dbg(&client->dev,
> - "EDT FT5x06 initialized: IRQ pin %d, Reset pin %d.\n",
> - pdata->irq_pin, pdata->reset_pin);
> + "EDT FT5x06 initialized: IRQ %d, WAKE pin %d, Reset pin %d.\n",
> + client->irq, tsdata->wake_pin, tsdata->reset_pin);
>
> return 0;
>
> @@ -813,18 +896,18 @@ err_free_irq:
> free_irq(client->irq, tsdata);
> err_free_mem:
> input_free_device(input);
> - kfree(tsdata);
> -
> - if (gpio_is_valid(pdata->irq_pin))
> - gpio_free(pdata->irq_pin);
> + if (gpio_is_valid(tsdata->irq_pin))
> + gpio_free(tsdata->irq_pin);
> + if (gpio_is_valid(tsdata->reset_pin))
> + gpio_free(tsdata->reset_pin);
> + if (gpio_is_valid(tsdata->wake_pin))
> + gpio_free(tsdata->wake_pin);

If you use devm_gpio_request_one(), these gpio_free()s are not
necessary.

>
> return error;
> }
>
> static int edt_ft5x06_ts_remove(struct i2c_client *client)
> {
> - const struct edt_ft5x06_platform_data *pdata =
> - dev_get_platdata(&client->dev);
> struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
>
> edt_ft5x06_ts_teardown_debugfs(tsdata);
> @@ -833,12 +916,12 @@ static int edt_ft5x06_ts_remove(struct i2c_client *client)
> free_irq(client->irq, tsdata);
> input_unregister_device(tsdata->input);
>
> - if (gpio_is_valid(pdata->irq_pin))
> - gpio_free(pdata->irq_pin);
> - if (gpio_is_valid(pdata->reset_pin))
> - gpio_free(pdata->reset_pin);
> -
> - kfree(tsdata);
> + if (gpio_is_valid(tsdata->irq_pin))
> + gpio_free(tsdata->irq_pin);
> + if (gpio_is_valid(tsdata->reset_pin))
> + gpio_free(tsdata->reset_pin);
> + if (gpio_is_valid(tsdata->wake_pin))
> + gpio_free(tsdata->wake_pin);

If you use devm_gpio_request_one(), these gpio_free()s are not
necessary.

Best regards,
Jingoo Han

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Next message: Eric W. Biederman: "Re: [RFC PATCH net-next 0/4] net_cls for sys container"
Previous message: tip-bot for Borislav Petkov: "[tip:x86/urgent] x86, cpu, amd: Add workaround for family 16h, erratum 793"
In reply to: Mark Rutland: "Re: [PATCH 2/2] Input: edt-ft5x06: Add DT support"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]