From mboxrd@z Thu Jan 1 00:00:00 1970 From: peter.chen@freescale.com (Peter Chen) Date: Fri, 13 Dec 2013 09:23:45 +0800 Subject: [PATCH v6 15/15] usb: phy-mxs: Add sync time after controller clear phcd In-Reply-To: <1386897825-6130-1-git-send-email-peter.chen@freescale.com> References: <1386897825-6130-1-git-send-email-peter.chen@freescale.com> Message-ID: <1386897825-6130-16-git-send-email-peter.chen@freescale.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org After clear portsc.phcd, PHY needs 200us stable time for switch 32K clock to AHB clock. Signed-off-by: Peter Chen --- drivers/usb/phy/phy-mxs-usb.c | 11 +++++++++++ 1 files changed, 11 insertions(+), 0 deletions(-) diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c index 885f8d9..68bd981 100644 --- a/drivers/usb/phy/phy-mxs-usb.c +++ b/drivers/usb/phy/phy-mxs-usb.c @@ -156,6 +156,15 @@ static inline bool is_imx6sl_phy(struct mxs_phy *mxs_phy) return mxs_phy->data == &imx6sl_phy_data; } +/* + * PHY needs some 32K cycles to switch from 32K clock to + * bus (such as AHB/AXI, etc) clock. + */ +static void mxs_phy_clock_switch_delay(void) +{ + usleep_range(300, 400); +} + static int mxs_phy_hw_init(struct mxs_phy *mxs_phy) { int ret; @@ -281,6 +290,7 @@ static int mxs_phy_init(struct usb_phy *phy) { struct mxs_phy *mxs_phy = to_mxs_phy(phy); + mxs_phy_clock_switch_delay(); clk_prepare_enable(mxs_phy->clk); return mxs_phy_hw_init(mxs_phy); } @@ -305,6 +315,7 @@ static int mxs_phy_suspend(struct usb_phy *x, int suspend) x->io_priv + HW_USBPHY_CTRL_SET); clk_disable_unprepare(mxs_phy->clk); } else { + mxs_phy_clock_switch_delay(); clk_prepare_enable(mxs_phy->clk); writel(BM_USBPHY_CTRL_CLKGATE, x->io_priv + HW_USBPHY_CTRL_CLR); -- 1.7.8