From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Chen Subject: [PATCH v11 12/15] usb: phy-mxs: Add sync time after controller clear phcd Date: Mon, 24 Feb 2014 10:21:04 +0800 Message-ID: <1393208467-6355-13-git-send-email-peter.chen@freescale.com> References: <1393208467-6355-1-git-send-email-peter.chen@freescale.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1393208467-6355-1-git-send-email-peter.chen@freescale.com> Sender: linux-doc-owner@vger.kernel.org To: balbi@ti.com, shawn.guo@linaro.org, robh+dt@kernel.org, grant.likely@linaro.org, pawel.moll@arm.com, mark.rutland@arm.com Cc: linux-usb@vger.kernel.org, linux-arm-kernel@lists.infradead.org, festevam@gmail.com, marex@denx.de, kernel@pengutronix.de, m.grzeschik@pengutronix.de, frank.li@freescale.com, peter.chen@freescale.com, gregkh@linuxfoundation.org, devicetree@vger.kernel.org, linux-doc@vger.kernel.org List-Id: devicetree@vger.kernel.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 31ef59f..c42bdf0 100644 --- a/drivers/usb/phy/phy-mxs-usb.c +++ b/drivers/usb/phy/phy-mxs-usb.c @@ -151,6 +151,15 @@ 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; @@ -261,6 +270,7 @@ static int mxs_phy_init(struct usb_phy *phy) int ret; struct mxs_phy *mxs_phy = to_mxs_phy(phy); + mxs_phy_clock_switch_delay(); ret = clk_prepare_enable(mxs_phy->clk); if (ret) return ret; @@ -289,6 +299,7 @@ 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(); ret = clk_prepare_enable(mxs_phy->clk); if (ret) return ret; -- 1.7.8