mxc_udc: add workaround for ENGcm09152 for i.MX35

this patch gives the possibility to workaround bug ENGcm09152
on i.MX35 when the hardware workaround is also implemented on
the board.
It covers the workaround described on page 25 of the following Errata :
http://cache.freescale.com/files/dsp/doc/errata/IMX35CE.pdf

Signed-off-by: Eric Bénard <eric@eukrea.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 19 insertions, 0 deletions

diff --git a/arch/arm/mach-mx3/mach-cpuimx35.c b/arch/arm/mach-mx3/mach-cpuimx35.c
index 2a4f8b781ba4..4d161b3fca65 100644
--- a/arch/arm/mach-mx3/mach-cpuimx35.c
+++ b/arch/arm/mach-mx3/mach-cpuimx35.c
@@ -155,6 +155,7 @@ static struct mxc_usbh_platform_data usbh1_pdata = {
 static struct fsl_usb2_platform_data otg_device_pdata = {
         .operating_mode = FSL_USB2_DR_DEVICE,
         .phy_mode       = FSL_USB2_PHY_UTMI,
+        .workaround     = FLS_USB2_WORKAROUND_ENGCM09152,
 };
 
 static int otg_mode_host;
diff --git a/drivers/usb/gadget/fsl_mxc_udc.c b/drivers/usb/gadget/fsl_mxc_udc.c
index eafa6d2c5ed7..5bdbfe619853 100644
--- a/drivers/usb/gadget/fsl_mxc_udc.c
+++ b/drivers/usb/gadget/fsl_mxc_udc.c
@@ -22,6 +22,10 @@
 static struct clk *mxc_ahb_clk;
 static struct clk *mxc_usb_clk;
 
+/* workaround ENGcm09152 for i.MX35 */
+#define USBPHYCTRL_OTGBASE_OFFSET       0x608
+#define USBPHYCTRL_EVDO                 (1 << 23)
+
 int fsl_udc_clk_init(struct platform_device *pdev)
 {
         struct fsl_usb2_platform_data *pdata;
@@ -84,6 +88,17 @@ eenahb:
 void fsl_udc_clk_finalize(struct platform_device *pdev)
 {
         struct fsl_usb2_platform_data *pdata = pdev->dev.platform_data;
+#if defined(CONFIG_ARCH_MX35)
+        unsigned int v;
+
+        /* workaround ENGcm09152 for i.MX35 */
+        if (pdata->workaround & FLS_USB2_WORKAROUND_ENGCM09152) {
+                v = readl(MX35_IO_ADDRESS(MX35_OTG_BASE_ADDR +
+                                USBPHYCTRL_OTGBASE_OFFSET));
+                writel(v | USBPHYCTRL_EVDO, MX35_IO_ADDRESS(MX35_OTG_BASE_ADDR +
+                                USBPHYCTRL_OTGBASE_OFFSET));
+        }
+#endif
 
         /* ULPI transceivers don't need usbpll */
         if (pdata->phy_mode == FSL_USB2_PHY_ULPI) {
diff --git a/include/linux/fsl_devices.h b/include/linux/fsl_devices.h
index d5f9a7431bd0..4eb56ed75fbc 100644
--- a/include/linux/fsl_devices.h
+++ b/include/linux/fsl_devices.h
@@ -66,6 +66,7 @@ struct fsl_usb2_platform_data {
         enum fsl_usb2_operating_modes   operating_mode;
         enum fsl_usb2_phy_modes         phy_mode;
         unsigned int                    port_enables;
+        unsigned int                    workaround;
 
         int             (*init)(struct platform_device *);
         void            (*exit)(struct platform_device *);
@@ -84,6 +85,8 @@ struct fsl_usb2_platform_data {
 #define FSL_USB2_PORT0_ENABLED  0x00000001
 #define FSL_USB2_PORT1_ENABLED  0x00000002
 
+#define FLS_USB2_WORKAROUND_ENGCM09152  (1 << 0)
+
 struct spi_device;
 
 struct fsl_spi_platform_data {