From 363366cf61c544ea476f3d220f43a95cb03014f5 Mon Sep 17 00:00:00 2001 From: Mike Thompson Date: Thu, 30 Aug 2012 18:26:25 -0300 Subject: [PATCH] usb: otg: mxs-phy: Fix mx23 operation Currently mx23 fails to enumerate a USB device: [ 1.300000] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1.520000] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1.740000] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1.960000] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 2.180000] hub 1-0:1.0: unable to enumerate USB device on port 1 Use a kernel workqueue to asynchronously delay the setting of ENHOSTDISCONDETECT bit until after higher level hub connect/reset processing is complete. Prematurely setting the bit prevents the connection processing from completing and not setting it prevents disconnect from being detected. No delay is needed for clearing of ENHOSTDISCONDETECT. Successfully tested on mx23-olinuxino (micro, mini and maxi variants) and mx28evk. Cc: stable@vger.kernel.org # v3.6 Signed-off-by: Mike Thompson Signed-off-by: Fabio Estevam Signed-off-by: Felipe Balbi --- drivers/usb/otg/mxs-phy.c | 38 +++++++++++++++++++++++++++++++++++--- 1 file changed, 35 insertions(+), 3 deletions(-) diff --git a/drivers/usb/otg/mxs-phy.c b/drivers/usb/otg/mxs-phy.c index c1a67cb..88db976 100644 --- a/drivers/usb/otg/mxs-phy.c +++ b/drivers/usb/otg/mxs-phy.c @@ -20,6 +20,7 @@ #include #include #include +#include #define DRIVER_NAME "mxs_phy" @@ -34,9 +35,16 @@ #define BM_USBPHY_CTRL_ENUTMILEVEL2 BIT(14) #define BM_USBPHY_CTRL_ENHOSTDISCONDETECT BIT(1) +/* + * Amount of delay in miliseconds to safely enable ENHOSTDISCONDETECT bit + * so that connection and reset processing can be completed for the root hub. + */ +#define MXY_PHY_ENHOSTDISCONDETECT_DELAY 250 + struct mxs_phy { struct usb_phy phy; struct clk *clk; + struct delayed_work enhostdiscondetect_work; }; #define to_mxs_phy(p) container_of((p), struct mxs_phy, phy) @@ -62,6 +70,7 @@ static int mxs_phy_init(struct usb_phy *phy) clk_prepare_enable(mxs_phy->clk); mxs_phy_hw_init(mxs_phy); + INIT_DELAYED_WORK(&mxs_phy->enhostdiscondetect_work, NULL); return 0; } @@ -76,13 +85,34 @@ static void mxs_phy_shutdown(struct usb_phy *phy) clk_disable_unprepare(mxs_phy->clk); } +static void mxs_phy_enhostdiscondetect_delay(struct work_struct *ws) +{ + struct mxs_phy *mxs_phy = container_of(ws, struct mxs_phy, + enhostdiscondetect_work.work); + + /* Enable HOSTDISCONDETECT after delay. */ + dev_dbg(mxs_phy->phy.dev, "Setting ENHOSTDISCONDETECT\n"); + writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT, + mxs_phy->phy.io_priv + HW_USBPHY_CTRL_SET); +} + static int mxs_phy_on_connect(struct usb_phy *phy, int port) { + struct mxs_phy *mxs_phy = to_mxs_phy(phy); + dev_dbg(phy->dev, "Connect on port %d\n", port); - mxs_phy_hw_init(to_mxs_phy(phy)); - writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT, - phy->io_priv + HW_USBPHY_CTRL_SET); + mxs_phy_hw_init(mxs_phy); + + /* + * Delay enabling ENHOSTDISCONDETECT so that connection and + * reset processing can be completed for the root hub. + */ + dev_dbg(phy->dev, "Delaying setting ENHOSTDISCONDETECT\n"); + PREPARE_DELAYED_WORK(&mxs_phy->enhostdiscondetect_work, + mxs_phy_enhostdiscondetect_delay); + schedule_delayed_work(&mxs_phy->enhostdiscondetect_work, + msecs_to_jiffies(MXY_PHY_ENHOSTDISCONDETECT_DELAY)); return 0; } @@ -91,6 +121,8 @@ static int mxs_phy_on_disconnect(struct usb_phy *phy, int port) { dev_dbg(phy->dev, "Disconnect on port %d\n", port); + /* No need to delay before clearing ENHOSTDISCONDETECT. */ + dev_dbg(phy->dev, "Clearing ENHOSTDISCONDETECT\n"); writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT, phy->io_priv + HW_USBPHY_CTRL_CLR); -- 2.7.4