[PATCH 4.2.y-ckt 002/211] drivers: usb :fsl: Implement Workaround for USB Erratum A007792

[Kamal Mostafa]

4.2.8-ckt1 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Nikhil Badola <nikhil.badola@xxxxxxxxxxxxx>

commit 523f1dec58408b36e7683a3d61a0286eed1fc1c8 upstream.

USB controller version-2.5 requires to enable internal UTMI
phy and program PTS field in PORTSC register before asserting
controller reset. This is must for successful resetting of the
controller and subsequent enumeration of usb devices

Signed-off-by: Nikhil Badola <nikhil.badola@xxxxxxxxxxxxx>
Signed-off-by: Suresh Gupta <suresh.gupta@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
 drivers/usb/host/ehci-fsl.c      | 9 +++++++++
 drivers/usb/host/fsl-mph-dr-of.c | 6 ++++++
 include/linux/fsl_devices.h      | 1 +
 3 files changed, 16 insertions(+)

diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
index 5352e74..716aa8b 100644
--- a/drivers/usb/host/ehci-fsl.c
+++ b/drivers/usb/host/ehci-fsl.c
@@ -129,6 +129,15 @@ static int fsl_ehci_drv_probe(struct platform_device *pdev)
 	if (pdata->have_sysif_regs && pdata->controller_ver < FSL_USB_VER_1_6)
 		setbits32(hcd->regs + FSL_SOC_USB_CTRL, 0x4);
 
+	/*
+	 * Enable UTMI phy and program PTS field in UTMI mode before asserting
+	 * controller reset for USB Controller version 2.5
+	 */
+	if (pdata->has_fsl_erratum_a007792) {
+		writel_be(CTRL_UTMI_PHY_EN, hcd->regs + FSL_SOC_USB_CTRL);
+		writel(PORT_PTS_UTMI, hcd->regs + FSL_SOC_USB_PORTSC1);
+	}
+
 	/* Don't need to set host mode here. It will be done by tdi_reset() */
 
 	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
diff --git a/drivers/usb/host/fsl-mph-dr-of.c b/drivers/usb/host/fsl-mph-dr-of.c
index 5e0d600..2ade376 100644
--- a/drivers/usb/host/fsl-mph-dr-of.c
+++ b/drivers/usb/host/fsl-mph-dr-of.c
@@ -214,6 +214,12 @@ static int fsl_usb2_mph_dr_of_probe(struct platform_device *ofdev)
 	pdata->phy_mode = determine_usb_phy(prop);
 	pdata->controller_ver = usb_get_ver_info(np);
 
+	/* Activate Erratum by reading property in device tree */
+	if (of_get_property(np, "fsl,usb-erratum-a007792", NULL))
+		pdata->has_fsl_erratum_a007792 = 1;
+	else
+		pdata->has_fsl_erratum_a007792 = 0;
+
 	if (pdata->have_sysif_regs) {
 		if (pdata->controller_ver < 0) {
 			dev_warn(&ofdev->dev, "Could not get controller version\n");
diff --git a/include/linux/fsl_devices.h b/include/linux/fsl_devices.h
index 2a2f56b..dfcf101397a 100644
--- a/include/linux/fsl_devices.h
+++ b/include/linux/fsl_devices.h
@@ -93,6 +93,7 @@ struct fsl_usb2_platform_data {
 
 	unsigned	suspended:1;
 	unsigned	already_suspended:1;
+	unsigned        has_fsl_erratum_a007792:1;
 
 	/* register save area for suspend/resume */
 	u32		pm_command;
-- 
1.9.1

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