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

[Marek Vasut]

On 6/5/24 12:02 PM, 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 | 44 +++++++++++++++++++++++++++++++++++++---
>   1 file changed, 41 insertions(+), 3 deletions(-)
> 
> diff --git a/common/usb_onboard_hub.c b/common/usb_onboard_hub.c
> index 89e18a2ddad..2f6fb71935d 100644
> --- a/common/usb_onboard_hub.c
> +++ b/common/usb_onboard_hub.c
> @@ -7,17 +7,26 @@
>    * Mostly inspired by Linux kernel v6.1 onboard_usb_hub driver
>    */
>   
> +#include <asm/gpio.h>
>   #include <common.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;
>   };
>   
>   static int usb_onboard_hub_probe(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;
>   
> @@ -31,7 +40,24 @@ static int usb_onboard_hub_probe(struct udevice *dev)
>   	if (ret)
>   		dev_err(dev, "can't enable vdd-supply: %d\n", ret);
>   
> -	return 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) {
> +		ret = dm_gpio_set_value(hub->reset_gpio, 1);
> +		if (ret)
> +			return ret;
> +
> +		udelay(data->reset_us);

Where is this assigned ?

> +		ret = dm_gpio_set_value(hub->reset_gpio, 0);
> +		if (ret)
> +			return ret;
> +
> +		udelay(data->reset_us);
> +	}

Is the reset asserted time and post-reset time identical for all USB 
HUBs ? I don't think it is.

> +	return 0;
>   }
>   
>   static int usb_onboard_hub_remove(struct udevice *dev)
> @@ -39,6 +65,12 @@ static int usb_onboard_hub_remove(struct udevice *dev)
>   	struct onboard_hub *hub = dev_get_priv(dev);
>   	int ret;
>   
> +	if (hub->reset_gpio) {
> +		struct gpio_desc *hub_reset_gpio = hub->reset_gpio;
> +
> +		dm_gpio_free(hub_reset_gpio->dev, hub_reset_gpio);
> +	}
> +
>   	ret = regulator_set_enable_if_allowed(hub->vdd, false);
>   	if (ret)
>   		dev_err(dev, "can't disable vdd-supply: %d\n", ret);
> @@ -46,10 +78,16 @@ static int usb_onboard_hub_remove(struct udevice *dev)
>   	return ret;
>   }
>   
> +static const struct onboard_hub_data usb2514_data = {
> +	/* TBD */

Do not add this if not used.