[PATCH v2 1/7] usb: onboard-hub: Add reset-gpio support

[Abbarapu, Venkatesh]

Hi Marek,

> -----Original Message-----
> From: Marek Vasut <marex at denx.de>
> Sent: Saturday, September 28, 2024 2:05 AM
> To: Abbarapu, Venkatesh <venkatesh.abbarapu at amd.com>; u-boot at lists.denx.de
> Cc: Simek, Michal <michal.simek at amd.com>; fabrice.gasnier at foss.st.com; git
> (AMD-Xilinx) <git at amd.com>
> Subject: Re: [PATCH v2 1/7] usb: onboard-hub: Add reset-gpio support
> 
> On 9/27/24 9:01 AM, Venkatesh Yadav Abbarapu wrote:
> 
> [...]
> 
> > @@ -30,7 +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 ?

This is assigned in this patch https://lore.kernel.org/u-boot/20240927070137.21816-4-venkatesh.abbarapu@amd.com/

+static const struct onboard_hub_data usb5744_data = {
+	.reset_us = 10000,
+	.power_on_delay_us = 10000,
+};


> 
> > +
> > +		ret = dm_gpio_set_value(hub->reset_gpio, 0);
> > +		if (ret)
> > +			return ret;
> > +
> > +		udelay(data->power_on_delay_us);
> > +	}
> 
> Is the reset asserted time and post-reset time identical for all USB HUBs ? I don't
> think it is.

Yes...it won't be the same for all the USB HUBs, as it needs to be updated in the onboard_hub_data structure as 

+static const struct onboard_hub_data usb5744_data = {
+	.reset_us = 10000,
+	.power_on_delay_us = 10000,
+};


Thanks
Venkatesh
> 
> > +	return 0;
> >   }
> [...]