[PATCH 4/4] usb: musb: da8xx: Implement BABBLE recovery

[Bastien Curutchet <bastien.curutchet@bootlin.com>]

There is no specific behaviour implemented to recover from a babble
error. When a BABBLE error happens, recovery fails as connected sticks
are no longer detected by the USB controller.

Implement the recover callback of the MUSB operation to reset the USB
controller when a BABBLE happens.

Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com>
---
 drivers/usb/musb/da8xx.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/usb/musb/da8xx.c b/drivers/usb/musb/da8xx.c
index c5cf733673a2..fcf06dcf2d61 100644
--- a/drivers/usb/musb/da8xx.c
+++ b/drivers/usb/musb/da8xx.c
@@ -220,6 +220,13 @@ static void __maybe_unused da8xx_musb_try_idle(struct musb *musb, unsigned long
 	mod_timer(&musb->dev_timer, timeout);
 }
 
+static int da8xx_babble_recover(struct musb *musb)
+{
+	dev_dbg(musb->controller, "resetting controller to recover from babble\n");
+	musb_writel(musb->ctrl_base, DA8XX_USB_CTRL_REG, DA8XX_SOFT_RESET_MASK);
+	return 0;
+}
+
 static irqreturn_t da8xx_musb_interrupt(int irq, void *hci)
 {
 	struct musb		*musb = hci;
@@ -480,6 +487,7 @@ static const struct musb_platform_ops da8xx_ops = {
 #ifndef CONFIG_USB_MUSB_HOST
 	.try_idle	= da8xx_musb_try_idle,
 #endif
+	.recover	= da8xx_babble_recover,
 
 	.set_vbus	= da8xx_musb_set_vbus,
 };
-- 
2.44.0