From mboxrd@z Thu Jan 1 00:00:00 1970 From: gautam.vivek@samsung.com (Vivek Gautam) Date: Tue, 2 Sep 2014 16:42:17 +0530 Subject: [PATCH v6 3/4] usb: hcd: Calibrate PHY post hcd reset In-Reply-To: <1409656338-20337-1-git-send-email-gautam.vivek@samsung.com> References: <1409656338-20337-1-git-send-email-gautam.vivek@samsung.com> Message-ID: <1409656338-20337-4-git-send-email-gautam.vivek@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Some quirky PHYs may require to be calibrated post the hcd initialization. The USB 3.0 DRD PHY on Exynos5420/5800 systems, coming along with Synopsys's DWC3 controller, is one such PHY which needs to be calibrated post xhci's reset at initialization time and at resume time, to get the controller work at SuperSpeed. So facilitating the HCDs to calibrate the PHY. Signed-off-by: Vivek Gautam --- drivers/usb/core/hcd.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index c4ed66c..6e01d09 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -2202,6 +2202,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) struct usb_hcd *hcd = container_of(rhdev->bus, struct usb_hcd, self); int status; int old_state = hcd->state; + int ret; dev_dbg(&rhdev->dev, "usb %sresume\n", (PMSG_IS_AUTO(msg) ? "auto-" : "")); @@ -2216,6 +2217,15 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) hcd->state = HC_STATE_RESUMING; status = hcd->driver->bus_resume(hcd); + + /* calibrate the phy here */ + ret = phy_calibrate(hcd->gen_phy); + if (ret < 0 && ret != -ENOTSUPP) { + dev_err(hcd->self.controller, + "failed to calibrate USB PHY\n"); + return ret; + } + clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); if (status == 0) { struct usb_device *udev; @@ -2738,6 +2748,14 @@ int usb_add_hcd(struct usb_hcd *hcd, } hcd->rh_pollable = 1; + /* calibrate the phy here */ + retval = phy_calibrate(hcd->gen_phy); + if (retval < 0 && retval != -ENOTSUPP) { + dev_err(hcd->self.controller, + "failed to calibrate USB PHY\n"); + return retval; + } + /* NOTE: root hub and controller capabilities may not be the same */ if (device_can_wakeup(hcd->self.controller) && device_can_wakeup(&hcd->self.root_hub->dev)) -- 1.7.10.4