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>
This commit is contained in:
Peter Chen 2014-11-26 13:44:32 +08:00 committed by Greg Kroah-Hartman
parent 947c88592f
commit cdd278f21e

View file

@ -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,