From e235f7b86f33beea7e096b46db1802dbf5d7d22e Mon Sep 17 00:00:00 2001 From: Peter Chen Date: Fri, 16 Jan 2015 18:29:01 +0800 Subject: [PATCH] usb: phy: mxs: add delay before set phyctrl.clkgate There is a request from IC engineer that if we doesn't set phypwd as 0xffffffff, we need to delay about five 32Khz cycles before set phy's pwd register, otherwise, the wakeup signal may can't wake up controller. Signed-off-by: Peter Chen Signed-off-by: Felipe Balbi --- drivers/usb/phy/phy-mxs-usb.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c index c3177a1757ee..8f7cb068d29b 100644 --- a/drivers/usb/phy/phy-mxs-usb.c +++ b/drivers/usb/phy/phy-mxs-usb.c @@ -371,10 +371,16 @@ static int mxs_phy_suspend(struct usb_phy *x, int suspend) * connect. The low speed connection will have problem at * very rare cases during usb suspend and resume process. */ - if (low_speed_connection & vbus_is_on) - writel(0xfffbffff, x->io_priv + HW_USBPHY_PWD); - else + if (low_speed_connection & vbus_is_on) { + /* + * If value to be set as pwd value is not 0xffffffff, + * several 32Khz cycles are needed. + */ + mxs_phy_clock_switch_delay(); + writel(0xffbfffff, x->io_priv + HW_USBPHY_PWD); + } else { writel(0xffffffff, x->io_priv + HW_USBPHY_PWD); + } writel(BM_USBPHY_CTRL_CLKGATE, x->io_priv + HW_USBPHY_CTRL_SET); clk_disable_unprepare(mxs_phy->clk); -- 2.20.1