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| author | Peter Chen <peter.chen@freescale.com> | 2014-11-26 13:44:32 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-11-26 09:28:12 -0800 |
| commit | cdd278f21eea55412dd0c5bc468bbdfb0639879b (patch) | |
| tree | f0a69b7d940161898c6ca7ee71cf02de946f9d8a /drivers/usb/chipidea/core.c | |
| parent | 947c88592f17bd299ff677049c3cda36cc6f93dd (diff) | |
| download | linux-stable-cdd278f21eea55412dd0c5bc468bbdfb0639879b.tar.gz linux-stable-cdd278f21eea55412dd0c5bc468bbdfb0639879b.tar.bz2 linux-stable-cdd278f21eea55412dd0c5bc468bbdfb0639879b.zip | |
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 <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/chipidea/core.c')
| -rw-r--r-- | drivers/usb/chipidea/core.c | 32 |
1 files changed, 28 insertions, 4 deletions
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, |