[PATCH v5 1/7] usb: onboard-hub: Add reset-gpio support

[Marek Vasut]

On 10/7/24 6:45 AM, Venkatesh Yadav Abbarapu wrote:
> As part of the reset, sets the direction of the pin to output before
> toggling the pin. Delay of millisecond is added in between low and
> high to meet the setup and hold time requirement of the reset.
> 
> Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu at amd.com>
> ---
>   common/usb_onboard_hub.c | 49 +++++++++++++++++++++++++++++++++++++++-
>   1 file changed, 48 insertions(+), 1 deletion(-)
> 
> diff --git a/common/usb_onboard_hub.c b/common/usb_onboard_hub.c
> index 68a04ac041..4317e81ed8 100644
> --- a/common/usb_onboard_hub.c
> +++ b/common/usb_onboard_hub.c
> @@ -7,14 +7,51 @@
>    * Mostly inspired by Linux kernel v6.1 onboard_usb_hub driver
>    */
>   
> +#include <asm/gpio.h>
>   #include <dm.h>
>   #include <dm/device_compat.h>
> +#include <linux/delay.h>
>   #include <power/regulator.h>
>   
>   struct onboard_hub {
>   	struct udevice *vdd;
> +	struct gpio_desc *reset_gpio;
>   };
>   
> +struct onboard_hub_data {
> +	unsigned long reset_us;
> +	unsigned long power_on_delay_us;
> +};
> +
> +int usb_onboard_hub_reset(struct udevice *dev)
> +{
> +	struct onboard_hub_data *data =
> +		(struct onboard_hub_data *)dev_get_driver_data(dev);
> +	struct onboard_hub *hub = dev_get_priv(dev);
> +	int ret;
> +
> +	hub->reset_gpio = devm_gpiod_get_optional(dev, "reset",
> +						  GPIOD_IS_OUT | GPIOD_ACTIVE_LOW);
> +
> +	/* property is optional, don't return error! */
> +	if (!hub->reset_gpio)
> +		return 0;
> +
> +	ret = dm_gpio_set_value(hub->reset_gpio, 1);
> +	if (ret)
> +		return ret;
> +
> +	udelay(data->reset_us);
> +
> +	ret = dm_gpio_set_value(hub->reset_gpio, 0);
> +	if (ret)
> +		return ret;
> +
> +	udelay(data->power_on_delay_us);
> +
> +	return 0;
> +}
> +
>   static int usb_onboard_hub_probe(struct udevice *dev)
>   {
>   	struct onboard_hub *hub = dev_get_priv(dev);
> @@ -30,7 +67,11 @@ static int usb_onboard_hub_probe(struct udevice *dev)
>   	if (ret)
>   		dev_err(dev, "can't enable vdd-supply: %d\n", ret);
>   
> -	return ret;
> +	ret = usb_onboard_hub_reset(dev);

return usb_onboard_hub_reset(dev);