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

[Ley Foon Tan]

On Tue, Aug 28, 2018 at 5:53 PM Marek Vasut <marex at denx.de> wrote:
>
> 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() function will assert the reset and free reset struct.
>
> > +     reset_release_bulk(&priv->resets);
> > +
> >       return 0;
> >  }
> >
> >
>
Regards
Ley Foon