[PATCH 3/4] usb: host: xhci-plat: Caibrate PHY post host reset
From: Vivek Gautam <hidden>
Date: 2014-06-06 12:12:51
Also in:
linux-samsung-soc, lkml
Subsystem:
the rest, usb subsystem, usb xhci driver · Maintainers:
Linus Torvalds, Greg Kroah-Hartman, Mathias Nyman
Some quirky PHYs may require to be calibrated post the host controller initialization. The USB 3.0 DRD PHY on Exynos5420/5800 systems is one such PHY which needs to calibrated post xhci's reset at initialization time and at resume time, to get the controller work at SuperSpeed. Signed-off-by: Vivek Gautam <redacted> --- drivers/usb/host/xhci-plat.c | 50 ++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 48 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index e7145b5..7be03df 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c@@ -32,10 +32,51 @@ static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci) xhci->quirks |= XHCI_PLAT; } +static int xhci_plat_calibrate_phy(struct xhci_hcd *xhci) +{ + int ret = 0; + struct usb_hcd *hcd = xhci_to_hcd(xhci); + + /* calibrate phy if available */ + if (!IS_ERR(xhci->phy2_gen)) { + ret = phy_calibrate(xhci->phy2_gen); + if (ret < 0 && ret != -ENOTSUPP) { + dev_err(hcd->self.controller, + "failed to calibrate USB 2.0 type PHY\n"); + return ret; + } + } + + if (!IS_ERR(xhci->phy3_gen)) { + ret = phy_calibrate(xhci->phy3_gen); + if (ret < 0 && ret != -ENOTSUPP) + dev_err(hcd->self.controller, + "failed to calibrate USB 3.0 type PHY\n"); + } + + return ret; +} + /* called during probe() after chip reset completes */ static int xhci_plat_setup(struct usb_hcd *hcd) { - return xhci_gen_setup(hcd, xhci_plat_quirks); + struct xhci_hcd *xhci; + int ret; + + ret = xhci_gen_setup(hcd, xhci_plat_quirks); + if (ret) { + dev_err(hcd->self.controller, "xhci setup failed\n"); + return ret; + } + + if (!usb_hcd_is_primary_hcd(hcd)) { + xhci = hcd_to_xhci(hcd); + ret = xhci_plat_calibrate_phy(xhci); + if (ret) + return ret; + } + + return 0; } static int xhci_plat_start(struct usb_hcd *hcd)
@@ -276,8 +317,13 @@ static int xhci_plat_resume(struct device *dev) { struct usb_hcd *hcd = dev_get_drvdata(dev); struct xhci_hcd *xhci = hcd_to_xhci(hcd); + int ret; + + ret = xhci_resume(xhci, 0); + if (ret) + return ret; - return xhci_resume(xhci, 0); + return xhci_plat_calibrate_phy(xhci); } static const struct dev_pm_ops xhci_plat_pm_ops = {
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1.7.10.4