[PATCH] USB: ehci-s5p: Fix phy reset

[Alexander Graf <agraf@suse.de>]

On my Exynos 5 based Arndale system, I need to pull the reset line down
and then let it go up again to actually perform a reset. Without that
reset, I can't find any USB hubs on my bus, rendering the USB controller
useless.

So this patch implements the above logic, making EHCI and OHCI work on
Arndale systems for me.

Signed-off-by: Alexander Graf <agraf@suse.de>
CC: Vivek Gautam <gautam.vivek@samsung.com>
CC: Jingoo Han <jg1.han@samsung.com>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Kukjin Kim <kgene.kim@samsung.com>
CC: Felipe Balbi <balbi@ti.com>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---

As this affects 3.9, this patch should definitely be considered for inclusion
there.
---
 drivers/usb/host/ehci-s5p.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/ehci-s5p.c b/drivers/usb/host/ehci-s5p.c
index 20ebf6a..c6d67e4 100644
--- a/drivers/usb/host/ehci-s5p.c
+++ b/drivers/usb/host/ehci-s5p.c
@@ -103,9 +103,15 @@ static void s5p_setup_vbus_gpio(struct platform_device *pdev)
 	if (!gpio_is_valid(gpio))
 		return;
 
-	err = gpio_request_one(gpio, GPIOF_OUT_INIT_HIGH, "ehci_vbus_gpio");
-	if (err)
+	/* reset pulls the line down, then up again */
+	err = gpio_request_one(gpio, GPIOF_OUT_INIT_LOW, "ehci_vbus_gpio");
+	if (err) {
 		dev_err(&pdev->dev, "can't request ehci vbus gpio %d", gpio);
+		return;
+	}
+	mdelay(1);
+	__gpio_set_value(gpio, 1);
+	gpio_free(gpio);
 }
 
 static u64 ehci_s5p_dma_mask = DMA_BIT_MASK(32);
-- 
1.7.12.4