Re: [PATCH v3 21/22] mfd: adp5585: add support for a reset pin

[Lee Jones <lee@kernel.org>]

On Mon, 12 May 2025, Nuno Sá via B4 Relay wrote:

> From: Nuno Sá <nuno.sa@analog.com>
> 
> Make sure to perform an Hardware reset during probe  if the pin is given
> in FW.
> 
> Signed-off-by: Nuno Sá <nuno.sa@analog.com>
> ---
>  drivers/mfd/adp5585.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/drivers/mfd/adp5585.c b/drivers/mfd/adp5585.c
> index 88401668f30e06ac201175470eeaf6216f3121d9..0fbe1f7f2582408b2e1b99f629182ceebce73fd7 100644
> --- a/drivers/mfd/adp5585.c
> +++ b/drivers/mfd/adp5585.c
> @@ -11,6 +11,7 @@
>  #include <linux/device.h>
>  #include <linux/err.h>
>  #include <linux/i2c.h>
> +#include <linux/gpio/consumer.h>
>  #include <linux/mfd/adp5585.h>
>  #include <linux/mfd/core.h>
>  #include <linux/mod_devicetable.h>
> @@ -712,6 +713,7 @@ static int adp5585_i2c_probe(struct i2c_client *i2c)
>  {
>  	struct regmap_config regmap_config;
>  	struct adp5585_dev *adp5585;
> +	struct gpio_desc *gpio;
>  	struct mfd_cell *devs;
>  	unsigned int id;
>  	int ret, n_devs;
> @@ -730,6 +732,20 @@ static int adp5585_i2c_probe(struct i2c_client *i2c)
>  	if (ret)
>  		return ret;
>  
> +	gpio = devm_gpiod_get_optional(&i2c->dev, "reset", GPIOD_OUT_HIGH);
> +	if (IS_ERR(gpio))
> +		return PTR_ERR(gpio);
> +
> +	/*
> +	 * Note the timings are not documented anywhere in the DS. They are just

It's okay, you can say "datasheet". :)

> +	 * reasonable values that work...

What does "..." mean in this context?

> +	 */
> +	if (gpio) {
> +		fsleep(30);
> +		gpiod_set_value_cansleep(gpio, 0);
> +		fsleep(60);
> +	}
> +
>  	adp5585->regmap = devm_regmap_init_i2c(i2c, &regmap_config);
>  	if (IS_ERR(adp5585->regmap))
>  		return dev_err_probe(&i2c->dev, PTR_ERR(adp5585->regmap),
> 
> -- 
> 2.49.0
> 
> 

-- 
Lee Jones [李琼斯]