queue-4.19/usb-chipidea-grab-the-legacy-usb-phy-by-phandle-firs.patch

   1 From e412980f55225885724a3f3a107e8f48e3ba4bd1 Mon Sep 17 00:00:00 2001
   2 From: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
   3 Date: Wed, 27 Feb 2019 06:51:36 +0000
   4 Subject: usb: chipidea: Grab the (legacy) USB PHY by phandle first
   5
   6 [ Upstream commit 68ef236274793066b9ba3154b16c0acc1c891e5c ]
   7
   8 According to the chipidea driver bindings, the USB PHY is specified via
   9 the "phys" phandle node. However, this only takes effect for USB PHYs
  10 that use the common PHY framework. For legacy USB PHYs, a simple lookup
  11 based on the USB PHY type is done instead.
  12
  13 This does not play out well when more than one USB PHY is registered,
  14 since the first registered PHY matching the type will always be
  15 returned regardless of what the driver was bound to.
  16
  17 Fix this by looking up the PHY based on the "phys" phandle node.
  18 Although generic PHYs are rather matched by their "phys-name" and not
  19 the "phys" phandle directly, there is no helper for similar lookup on
  20 legacy PHYs and it's probably not worth the effort to add it.
  21
  22 When no legacy USB PHY is found by phandle, fallback to grabbing any
  23 registered USB2 PHY. This ensures backward compatibility if some users
  24 were actually relying on this mechanism.
  25
  26 Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
  27 Signed-off-by: Peter Chen <peter.chen@nxp.com>
  28 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  29 Signed-off-by: Sasha Levin <sashal@kernel.org>
  30 ---
  31  drivers/usb/chipidea/core.c | 9 ++++++++-
  32  1 file changed, 8 insertions(+), 1 deletion(-)
  33
  34 diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
  35 index 85fc6db48e44..159b897c5e80 100644
  36 --- a/drivers/usb/chipidea/core.c
  37 +++ b/drivers/usb/chipidea/core.c
  38 @@ -935,8 +935,15 @@ static int ci_hdrc_probe(struct platform_device *pdev)
  39         } else if (ci->platdata->usb_phy) {
  40                 ci->usb_phy = ci->platdata->usb_phy;
  41         } else {
  42 +               ci->usb_phy = devm_usb_get_phy_by_phandle(dev->parent, "phys",
  43 +                                                         0);
  44                 ci->phy = devm_phy_get(dev->parent, "usb-phy");
  45 -               ci->usb_phy = devm_usb_get_phy(dev->parent, USB_PHY_TYPE_USB2);
  46 +
  47 +               /* Fallback to grabbing any registered USB2 PHY */
  48 +               if (IS_ERR(ci->usb_phy) &&
  49 +                   PTR_ERR(ci->usb_phy) != -EPROBE_DEFER)
  50 +                       ci->usb_phy = devm_usb_get_phy(dev->parent,
  51 +                                                      USB_PHY_TYPE_USB2);
  52
  53                 /* if both generic PHY and USB PHY layers aren't enabled */
  54                 if (PTR_ERR(ci->phy) == -ENOSYS &&
  55 --
  56 2.19.1
  57