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

[Patrick DELAUNAY]

> -----Original Message-----
> From: Simon Goldschmidt <simon.k.r.goldschmidt at gmail.com>
> Sent: mercredi 4 mars 2020 20:52
> To: Patrick DELAUNAY <patrick.delaunay at st.com>; u-boot at lists.denx.de
> Cc: ley.foon.tan at intel.com; b.galvani at gmail.com; Daniel Schwierzeck
> <daniel.schwierzeck at gmail.com>; Marek Vasut <marex at denx.de>; Michal
> Suchanek <msuchanek at suse.de>; Simon Glass <sjg at chromium.org>; U-Boot
> STM32 <uboot-stm32 at st-md-mailman.stormreply.com>
> Subject: Re: [PATCH v4 2/5] usb: host: dwc2: add phy support
> Importance: High
> 
> 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?

Yes in V5, it is more clear

	ret = generic_phy_get_by_index(dev, 0, &priv->phy);
	if (ret) {
		if (ret == -ENOENT)
			return 0; /* no PHY, nothing to do */
		dev_err(dev, "Failed to get USB PHY: %d.\n", ret);
		return ret;
	}

> > +			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.

Yes in V5:

static int dwc2_shutdown_phy(struct udevice *dev)
{
	struct dwc2_priv *priv = dev_get_priv(dev);
	int ret;

	/* PHY is not valid when generic_phy_get_by_index() = -ENOENT */
	if (!generic_phy_valid(&priv->phy))
		return 0; /* no PHY, nothing to do */


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

Thanks 
Regards

Patrick