On Tue, 21 Nov 2023, Dmitry Rokosov wrote:
> HWEN is hardware control, which is used for enable/disable aw200xx chip.
> It's high active, internally pulled down to GND.
>
> After HWEN pin set high the chip begins to load the OTP information,
> which takes 200us to complete. About 200us wait time is needed for
> internal oscillator startup and display SRAM initialization. After
> display SRAM initialization, the registers in page 1 to page 5 can be
> configured via i2c interface.
>
> Signed-off-by: Dmitry Rokosov <ddrokosov@xxxxxxxxxxxxxxxxx>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> ---
> drivers/leds/leds-aw200xx.c | 33 +++++++++++++++++++++++++++++++++
> 1 file changed, 33 insertions(+)
>
> diff --git a/drivers/leds/leds-aw200xx.c b/drivers/leds/leds-aw200xx.c
> index 842a22087b16..7762b3a132ac 100644
> --- a/drivers/leds/leds-aw200xx.c
> +++ b/drivers/leds/leds-aw200xx.c
> @@ -10,6 +10,7 @@
> #include <linux/bitfield.h>
> #include <linux/bits.h>
> #include <linux/container_of.h>
> +#include <linux/gpio/consumer.h>
> #include <linux/i2c.h>
> #include <linux/leds.h>
> #include <linux/mod_devicetable.h>
> @@ -116,6 +117,7 @@ struct aw200xx {
> struct mutex mutex;
> u32 num_leds;
> u32 display_rows;
> + struct gpio_desc *hwen;
> struct aw200xx_led leds[] __counted_by(num_leds);
> };
>
> @@ -358,6 +360,25 @@ static int aw200xx_chip_check(const struct aw200xx *const chip)
> return 0;
> }
>
> +static void aw200xx_enable(const struct aw200xx *const chip)
> +{
> + gpiod_set_value_cansleep(chip->hwen, 1);
> +
> + /*
> + * After HWEN pin set high the chip begins to load the OTP information,
> + * which takes 200us to complete. About 200us wait time is needed for
> + * internal oscillator startup and display SRAM initialization. After
> + * display SRAM initialization, the registers in page1 to page5 can be
> + * configured via i2c interface.
> + */
> + fsleep(400);
> +}
> +
> +static void aw200xx_disable(const struct aw200xx *const chip)
> +{
> + return gpiod_set_value_cansleep(chip->hwen, 0);
> +}
> +
> static int aw200xx_probe_fw(struct device *dev, struct aw200xx *chip)
> {
> struct fwnode_handle *child;
> @@ -517,6 +538,14 @@ static int aw200xx_probe(struct i2c_client *client)
> if (IS_ERR(chip->regmap))
> return PTR_ERR(chip->regmap);
>
> + chip->hwen = devm_gpiod_get_optional(&client->dev, "enable",
> + GPIOD_OUT_HIGH);
> + if (IS_ERR(chip->hwen))
> + return dev_err_probe(&client->dev, PTR_ERR(chip->hwen),
> + "Cannot get enable gpio");
Nit: "GPIO"
> +
> + aw200xx_enable(chip);
> +
> ret = aw200xx_chip_check(chip);
> if (ret)
> return ret;
> @@ -537,6 +566,9 @@ static int aw200xx_probe(struct i2c_client *client)
> ret = aw200xx_chip_init(chip);
>
> out_unlock:
> + if (ret)
> + aw200xx_disable(chip);
> +
> mutex_unlock(&chip->mutex);
> return ret;
> }
> @@ -546,6 +578,7 @@ static void aw200xx_remove(struct i2c_client *client)
> struct aw200xx *chip = i2c_get_clientdata(client);
>
> aw200xx_chip_reset(chip);
> + aw200xx_disable(chip);
> mutex_destroy(&chip->mutex);
> }
>
> --
> 2.36.0
>
--
Lee Jones [李琼斯]
