[PATCH v4 2/5] usb: host: dwc2: add phy support

[Simon Goldschmidt]

Am 18.02.2020 um 09:35 schrieb Patrick Delaunay:
> Use generic phy to initialize the PHY associated to the
> DWC2 device and available in the device tree.
> 
> This patch don't added dependency because when CONFIG_PHY
> is not activated, the generic PHY function are stubbed.
> 
> Signed-off-by: Patrick Delaunay <patrick.delaunay at st.com>
> ---
> 
> Changes in v4: None
> Changes in v3: None
> Changes in v2:
> - update dev_err
> - update commit message
> - change dev_err to dev_dbg for PHY function call
> - treat dwc2_shutdown_phy error
> 
>  drivers/usb/host/dwc2.c | 66 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 66 insertions(+)
> 
> diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c
> index e4efaf1e59..5e7ffaddd9 100644
> --- a/drivers/usb/host/dwc2.c
> +++ b/drivers/usb/host/dwc2.c
> @@ -8,6 +8,7 @@
>  #include <cpu_func.h>
>  #include <dm.h>
>  #include <errno.h>
> +#include <generic-phy.h>
>  #include <usb.h>
>  #include <malloc.h>
>  #include <memalign.h>
> @@ -37,6 +38,7 @@ struct dwc2_priv {
>  #ifdef CONFIG_DM_REGULATOR
>  	struct udevice *vbus_supply;
>  #endif
> +	struct phy phy;
>  #else
>  	uint8_t *aligned_buffer;
>  	uint8_t *status_buffer;
> @@ -1322,13 +1324,71 @@ static int dwc2_usb_ofdata_to_platdata(struct udevice *dev)
>  	return 0;
>  }
>  
> +static int dwc2_setup_phy(struct udevice *dev)
> +{
> +	struct dwc2_priv *priv = dev_get_priv(dev);
> +	int ret;
> +
> +	ret = generic_phy_get_by_index(dev, 0, &priv->phy);
> +	if (ret) {
> +		if (ret != -ENOENT) {

Could you invert this logic and add a comment like "no PHY" or something?

> +			dev_err(dev, "Failed to get USB PHY: %d.\n", ret);
> +			return ret;
> +		}
> +		return 0;
> +	}
> +
> +	ret = generic_phy_init(&priv->phy);
> +	if (ret) {
> +		dev_dbg(dev, "Failed to init USB PHY: %d.\n", ret);
> +		return ret;
> +	}
> +
> +	ret = generic_phy_power_on(&priv->phy);
> +	if (ret) {
> +		dev_dbg(dev, "Failed to power on USB PHY: %d.\n", ret);
> +		generic_phy_exit(&priv->phy);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int dwc2_shutdown_phy(struct udevice *dev)
> +{
> +	struct dwc2_priv *priv = dev_get_priv(dev);
> +	int ret;
> +
> +	if (!generic_phy_valid(&priv->phy))

A comment saying that this is for platforms without a phy driver would
be nice.

Other than that:
Reviewed-by: Simon Goldschmidt <simon.k.r.goldschmidt at gmail.com>

> +		return 0;
> +
> +	ret = generic_phy_power_off(&priv->phy);
> +	if (ret) {
> +		dev_dbg(dev, "Failed to power off USB PHY: %d.\n", ret);
> +		return ret;
> +	}
> +
> +	ret = generic_phy_exit(&priv->phy);
> +	if (ret) {
> +		dev_dbg(dev, "Failed to power off USB PHY: %d.\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
>  static int dwc2_usb_probe(struct udevice *dev)
>  {
>  	struct dwc2_priv *priv = dev_get_priv(dev);
>  	struct usb_bus_priv *bus_priv = dev_get_uclass_priv(dev);
> +	int ret;
>  
>  	bus_priv->desc_before_addr = true;
>  
> +	ret = dwc2_setup_phy(dev);
> +	if (ret)
> +		return ret;
> +
>  	return dwc2_init_common(dev, priv);
>  }
>  
> @@ -1341,6 +1401,12 @@ static int dwc2_usb_remove(struct udevice *dev)
>  	if (ret)
>  		return ret;
>  
> +	ret = dwc2_shutdown_phy(dev);
> +	if (ret) {
> +		dev_dbg(dev, "Failed to shutdown USB PHY: %d.\n", ret);
> +		return ret;
> +	}
> +
>  	dwc2_uninit_common(priv->regs);
>  
>  	reset_release_bulk(&priv->resets);
>