[12/16] usb: musb: Add a quirk to preserve the session during suspend

Message ID 1483456521-24416-13-git-send-email-b-liu@ti.com
State Superseded
Headers show

Commit Message

Bin Liu Jan. 3, 2017, 3:15 p.m.
From: Alexandre Bailon <abailon@baylibre.com>

On da8xx, VBUS is not maintained during suspend when musb is in host mode.
On resume, all the connected devices will be disconnected and then will
be enumerated again.
This happens because MUSB_DEVCTL is cleared during suspend.
Add a quirk to not clear MUSB_DEVCTL and then preserve the  session during
a suspend.

Signed-off-by: Alexandre Bailon <abailon@baylibre.com>

Signed-off-by: Bin Liu <b-liu@ti.com>

 drivers/usb/musb/musb_core.c | 3 ++-
 drivers/usb/musb/musb_core.h | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)


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diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index 3dd9cc96634e..79c3daec0d4b 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -2660,7 +2660,8 @@  static int musb_suspend(struct device *dev)
-	musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
+	if (!(musb->io.quirks & MUSB_PRESERVE_SESSION))
+		musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
 	spin_lock_irqsave(&musb->lock, flags);
diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h
index ade902ea1221..ab0c858af9d3 100644
--- a/drivers/usb/musb/musb_core.h
+++ b/drivers/usb/musb/musb_core.h
@@ -172,6 +172,7 @@  enum musb_g_ep0_state {
 struct musb_platform_ops {
 #define MUSB_DMA_UX500		BIT(6)
 #define MUSB_DMA_CPPI41		BIT(5)
 #define MUSB_DMA_CPPI		BIT(4)