[4.2.y-ckt stable] Patch "drivers: usb :fsl: Implement Workaround for USB Erratum A007792" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    drivers: usb :fsl: Implement Workaround for USB Erratum A007792

to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-4.2.y-queue

This patch is scheduled to be released in version 4.2.8-ckt1.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 4.2.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From ae14b033cd26741ef61f7b5a8cc8e151d8be8e36 Mon Sep 17 00:00:00 2001
From: Nikhil Badola <nikhil.badola at freescale.com>
Date: Mon, 15 Jun 2015 15:47:29 +0530
Subject: drivers: usb :fsl: Implement Workaround for USB Erratum A007792

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 at freescale.com>
Signed-off-by: Suresh Gupta <suresh.gupta at freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 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