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 <ag...@suse.de>
CC: Vivek Gautam <gautam.vi...@samsung.com>
CC: Jingoo Han <jg1....@samsung.com>
CC: Alan Stern <st...@rowland.harvard.edu>
CC: Kukjin Kim <kgene....@samsung.com>
CC: Felipe Balbi <ba...@ti.com>
CC: Greg Kroah-Hartman <gre...@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
--
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