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* [PATCH] usb: musb: Disable pullup at init
@ 2019-12-14 22:18 Paul Cercueil
  2019-12-16 16:21 ` Bin Liu
  0 siblings, 1 reply; 2+ messages in thread
From: Paul Cercueil @ 2019-12-14 22:18 UTC (permalink / raw)
  To: Bin Liu, Greg Kroah-Hartman; +Cc: od, linux-usb, linux-kernel, Paul Cercueil

The pullup may be already enabled before the driver is initialized. This
happens for instance on JZ4740.

It has to be disabled at init time, as we cannot guarantee that a gadget
driver will be bound to the UDC.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Suggested-by: Bin Liu <b-liu@ti.com>
---
 drivers/usb/musb/musb_core.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index 15cca912c53e..c91d5c2ed4ad 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -2310,6 +2310,9 @@ musb_init_controller(struct device *dev, int nIrq, void __iomem *ctrl)
 	musb_disable_interrupts(musb);
 	musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
 
+	/* MUSB_POWER_SOFTCONN might be already set, JZ4740 does this. */
+	musb_writeb(musb->mregs, MUSB_POWER, 0);
+
 	/* Init IRQ workqueue before request_irq */
 	INIT_DELAYED_WORK(&musb->irq_work, musb_irq_work);
 	INIT_DELAYED_WORK(&musb->deassert_reset_work, musb_deassert_reset);
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH] usb: musb: Disable pullup at init
  2019-12-14 22:18 [PATCH] usb: musb: Disable pullup at init Paul Cercueil
@ 2019-12-16 16:21 ` Bin Liu
  0 siblings, 0 replies; 2+ messages in thread
From: Bin Liu @ 2019-12-16 16:21 UTC (permalink / raw)
  To: Paul Cercueil; +Cc: Greg Kroah-Hartman, od, linux-usb, linux-kernel

On Sat, Dec 14, 2019 at 11:18:15PM +0100, Paul Cercueil wrote:
> The pullup may be already enabled before the driver is initialized. This
> happens for instance on JZ4740.
> 
> It has to be disabled at init time, as we cannot guarantee that a gadget
> driver will be bound to the UDC.
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Suggested-by: Bin Liu <b-liu@ti.com>

Applied. Thanks.

-Bin.

^ permalink raw reply	[flat|nested] 2+ messages in thread

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