From cdd278f21eea55412dd0c5bc468bbdfb0639879b Mon Sep 17 00:00:00 2001 From: Peter Chen Date: Wed, 26 Nov 2014 13:44:32 +0800 Subject: usb: chipidea: add controller reset API Add controller reset API, currently it is used for device mode only. It may be used for host/otg driver in future. Ususally, we need this API for dual-role switch and back from hibernation suspend to let the controller at default state. Signed-off-by: Peter Chen Signed-off-by: Greg Kroah-Hartman --- drivers/usb/chipidea/core.c | 32 ++++++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-) (limited to 'drivers/usb/chipidea') diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c index bd74f27a95e5..48b25d9ebf82 100644 --- a/drivers/usb/chipidea/core.c +++ b/drivers/usb/chipidea/core.c @@ -385,20 +385,44 @@ static int ci_usb_phy_init(struct ci_hdrc *ci) } /** - * hw_device_reset: resets chip (execute without interruption) + * hw_controller_reset: do controller reset * @ci: the controller * * This function returns an error code */ +static int hw_controller_reset(struct ci_hdrc *ci) +{ + int count = 0; + + hw_write(ci, OP_USBCMD, USBCMD_RST, USBCMD_RST); + while (hw_read(ci, OP_USBCMD, USBCMD_RST)) { + udelay(10); + if (count++ > 1000) + return -ETIMEDOUT; + } + + return 0; +} + +/** + * hw_device_reset: resets chip (execute without interruption) + * @ci: the controller + * + * This function returns an error code + */ int hw_device_reset(struct ci_hdrc *ci, u32 mode) { + int ret; + /* should flush & stop before reset */ hw_write(ci, OP_ENDPTFLUSH, ~0, ~0); hw_write(ci, OP_USBCMD, USBCMD_RS, 0); - hw_write(ci, OP_USBCMD, USBCMD_RST, USBCMD_RST); - while (hw_read(ci, OP_USBCMD, USBCMD_RST)) - udelay(10); /* not RTOS friendly */ + ret = hw_controller_reset(ci); + if (ret) { + dev_err(ci->dev, "error resetting controller, ret=%d\n", ret); + return ret; + } if (ci->platdata->notify_event) ci->platdata->notify_event(ci, -- cgit v1.2.1