[U-Boot] [PATCH v3] usb: dwc2: Add reset ctrl to driver

[Marek Vasut]

On 08/28/2018 06:08 PM, Ley Foon Tan wrote:
> Add code to reset all reset signals as in usb DT node. A reset property
> is an optional feature, so only print out a warning and do not fail if a
> reset property is not present.
> 
> If a reset property is discovered, then use it to deassert, thus
> bringing the IP out of reset.
> 
> Signed-off-by: Ley Foon Tan <ley.foon.tan at intel.com>
> 
> ---
> v3:
> - Add error handling when return non-zero from reset_get_bulk().
> 
> v2:
> - Add reset_release_bulk() in _remove function.
> ---
>  drivers/usb/host/dwc2.c |   37 +++++++++++++++++++++++++++++++++++++
>  1 files changed, 37 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c
> index cbe065b..b6f008a 100644
> --- a/drivers/usb/host/dwc2.c
> +++ b/drivers/usb/host/dwc2.c
> @@ -15,6 +15,7 @@
>  #include <wait_bit.h>
>  #include <asm/io.h>
>  #include <power/regulator.h>
> +#include <reset.h>
>  
>  #include "dwc2.h"
>  
> @@ -49,6 +50,8 @@ struct dwc2_priv {
>  	 */
>  	bool hnp_srp_disable;
>  	bool oc_disable;
> +
> +	struct reset_ctl_bulk	resets;
>  };
>  
>  #ifndef CONFIG_DM_USB
> @@ -1124,11 +1127,43 @@ int _submit_int_msg(struct dwc2_priv *priv, struct usb_device *dev,
>  	}
>  }
>  
> +static int dwc2_reset(struct udevice *dev)
> +{
> +	int ret;
> +	struct dwc2_priv *priv = dev_get_priv(dev);
> +
> +	ret = reset_get_bulk(dev, &priv->resets);
> +	if (ret) {
> +		dev_warn(dev, "Can't get reset: %d\n", ret);
> +		/* Return 0 if error due to !CONFIG_DM_RESET and reset
> +		 * DT property is not present.
> +		 */
> +		if (ret == -ENOENT || ret == -ENOTSUPP)
> +			return 0;
> +		else
> +			return ret;
> +	}
> +
> +	ret = reset_deassert_bulk(&priv->resets);
> +	if (ret) {
> +		reset_release_bulk(&priv->resets);
> +		dev_err(dev, "Failed to reset: %d\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
>  static int dwc2_init_common(struct udevice *dev, struct dwc2_priv *priv)
>  {
>  	struct dwc2_core_regs *regs = priv->regs;
>  	uint32_t snpsid;
>  	int i, j;
> +	int ret;
> +
> +	ret = dwc2_reset(dev);
> +	if (ret)
> +		return ret;
>  
>  	snpsid = readl(&regs->gsnpsid);
>  	dev_info(dev, "Core Release: %x.%03x\n",
> @@ -1303,6 +1338,8 @@ static int dwc2_usb_remove(struct udevice *dev)
>  
>  	dwc2_uninit_common(priv->regs);
>  

Don't you need to assert the reset here ?

> +	reset_release_bulk(&priv->resets);
> +
>  	return 0;
>  }
>  
> 


-- 
Best regards,
Marek Vasut