USB: ehci-mxc: add work-around for efika mx/sb bug
Add support for setting CHRGVBUS to workaround a hardware bug on efika mx/sb
boards.
See http://lists.infradead.org/pipermail/linux-arm-kernel/2011-January/037341.html
Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/host/ehci-mxc.c b/drivers/usb/host/ehci-mxc.c
index d443fbd..c8e360d 100644
--- a/drivers/usb/host/ehci-mxc.c
+++ b/drivers/usb/host/ehci-mxc.c
@@ -21,10 +21,13 @@
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/usb/otg.h>
+#include <linux/usb/ulpi.h>
#include <linux/slab.h>
#include <mach/mxc_ehci.h>
+#include <asm/mach-types.h>
+
#define ULPI_VIEWPORT_OFFSET 0x170
struct ehci_mxc_priv {
@@ -114,6 +117,7 @@
struct usb_hcd *hcd;
struct resource *res;
int irq, ret;
+ unsigned int flags;
struct ehci_mxc_priv *priv;
struct device *dev = &pdev->dev;
struct ehci_hcd *ehci;
@@ -240,6 +244,23 @@
if (ret)
goto err_add;
+ if (pdata->otg) {
+ /*
+ * efikamx and efikasb have some hardware bug which is
+ * preventing usb to work unless CHRGVBUS is set.
+ * It's in violation of USB specs
+ */
+ if (machine_is_mx51_efikamx() || machine_is_mx51_efikasb()) {
+ flags = otg_io_read(pdata->otg, ULPI_OTG_CTRL);
+ flags |= ULPI_OTG_CTRL_CHRGVBUS;
+ ret = otg_io_write(pdata->otg, flags, ULPI_OTG_CTRL);
+ if (ret) {
+ dev_err(dev, "unable to set CHRVBUS\n");
+ goto err_add;
+ }
+ }
+ }
+
return 0;
err_add:
