patches.baytrail/0003-usb-xhci-check-usb2-port-capabilities-before-adding-.patch

From 1c3285798797058421f167d3ae49b1d938d0dbc0 Mon Sep 17 00:00:00 2001
From: Mathias Nyman <mathias.nyman@linux.intel.com>
Date: Thu, 23 May 2013 17:14:28 +0300
Subject: usb: xhci: check usb2 port capabilities before adding hw link PM
 support

Hardware link powermanagement in usb2 is a per-port capability.
Previously support for hw lpm was enabled for all ports if any usb2 port supported it.

Now instead cache the capability values and check them for each port individually

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
(cherry picked from commit b630d4b9d05ba2e66878ca4614946d0f950d4111)
Signed-off-by: Benson Leung <bleung@chromium.org>


Reviewed-on: https://chromium-review.googlesource.com/169210
Reviewed-by: Julius Werner <jwerner@chromium.org>
Commit-Queue: Benson Leung <bleung@chromium.org>
Tested-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
---
 drivers/usb/host/xhci-mem.c |   33 +++++++++++++++++++++++++++++----
 drivers/usb/host/xhci.c     |   27 ++++++++++++++++++++++++++-
 drivers/usb/host/xhci.h     |    3 +++
 3 files changed, 58 insertions(+), 5 deletions(-)

--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1860,6 +1860,7 @@ no_bw:
 	kfree(xhci->usb3_ports);
 	kfree(xhci->port_array);
 	kfree(xhci->rh_bw);
+	kfree(xhci->ext_caps);
 
 	xhci->usb2_ports = NULL;
 	xhci->usb3_ports = NULL;
@@ -2052,7 +2053,7 @@ static void xhci_set_hc_event_deq(struct
 }
 
 static void xhci_add_in_port(struct xhci_hcd *xhci, unsigned int num_ports,
-		__le32 __iomem *addr, u8 major_revision)
+		__le32 __iomem *addr, u8 major_revision, int max_caps)
 {
 	u32 temp, port_offset, port_count;
 	int i;
@@ -2077,6 +2078,10 @@ static void xhci_add_in_port(struct xhci
 		/* WTF? "Valid values are ‘1’ to MaxPorts" */
 		return;
 
+	/* cache usb2 port capabilities */
+	if (major_revision < 0x03 && xhci->num_ext_caps < max_caps)
+		xhci->ext_caps[xhci->num_ext_caps++] = temp;
+
 	/* Check the host's USB2 LPM capability */
 	if ((xhci->hci_version == 0x96) && (major_revision != 0x03) &&
 			(temp & XHCI_L1C)) {
@@ -2134,10 +2139,11 @@ static void xhci_add_in_port(struct xhci
  */
 static int xhci_setup_port_arrays(struct xhci_hcd *xhci, gfp_t flags)
 {
-	__le32 __iomem *addr;
-	u32 offset;
+	__le32 __iomem *addr, *tmp_addr;
+	u32 offset, tmp_offset;
 	unsigned int num_ports;
 	int i, j, port_index;
+	int cap_count = 0;
 
 	addr = &xhci->cap_regs->hcc_params;
 	offset = XHCI_HCC_EXT_CAPS(xhci_readl(xhci, addr));
@@ -2170,13 +2176,32 @@ static int xhci_setup_port_arrays(struct
 	 * See section 5.3.6 for offset calculation.
 	 */
 	addr = &xhci->cap_regs->hc_capbase + offset;
+
+	tmp_addr = addr;
+	tmp_offset = offset;
+
+	/* count extended protocol capability entries for later caching */
+	do {
+		u32 cap_id;
+		cap_id = xhci_readl(xhci, tmp_addr);
+		if (XHCI_EXT_CAPS_ID(cap_id) == XHCI_EXT_CAPS_PROTOCOL)
+			cap_count++;
+		tmp_offset = XHCI_EXT_CAPS_NEXT(cap_id);
+		tmp_addr += tmp_offset;
+	} while (tmp_offset);
+
+	xhci->ext_caps = kzalloc(sizeof(*xhci->ext_caps) * cap_count, flags);
+	if (!xhci->ext_caps)
+		return -ENOMEM;
+
 	while (1) {
 		u32 cap_id;
 
 		cap_id = xhci_readl(xhci, addr);
 		if (XHCI_EXT_CAPS_ID(cap_id) == XHCI_EXT_CAPS_PROTOCOL)
 			xhci_add_in_port(xhci, num_ports, addr,
-					(u8) XHCI_EXT_PORT_MAJOR(cap_id));
+					(u8) XHCI_EXT_PORT_MAJOR(cap_id),
+					cap_count);
 		offset = XHCI_EXT_CAPS_NEXT(cap_id);
 		if (!offset || (xhci->num_usb2_ports + xhci->num_usb3_ports)
 				== num_ports)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -4063,15 +4063,40 @@ int xhci_set_usb2_hardware_lpm(struct us
 	return 0;
 }
 
+/* check if a usb2 port supports a given extened capability protocol
+ * only USB2 ports extended protocol capability values are cached.
+ * Return 1 if capability is supported
+ */
+static int xhci_check_usb2_port_capability(struct xhci_hcd *xhci, int port,
+					   unsigned capability)
+{
+	u32 port_offset, port_count;
+	int i;
+
+	for (i = 0; i < xhci->num_ext_caps; i++) {
+		if (xhci->ext_caps[i] & capability) {
+			/* port offsets starts at 1 */
+			port_offset = XHCI_EXT_PORT_OFF(xhci->ext_caps[i]) - 1;
+			port_count = XHCI_EXT_PORT_COUNT(xhci->ext_caps[i]);
+			if (port >= port_offset &&
+			    port < port_offset + port_count)
+				return 1;
+		}
+	}
+	return 0;
+}
+
 int xhci_update_device(struct usb_hcd *hcd, struct usb_device *udev)
 {
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
 	int		ret;
+	int		portnum = udev->portnum - 1;
 
 	ret = xhci_usb2_software_lpm_test(hcd, udev);
 	if (!ret) {
 		xhci_dbg(xhci, "software LPM test succeed\n");
-		if (xhci->hw_lpm_support == 1) {
+		if (xhci->hw_lpm_support == 1 &&
+		    xhci_check_usb2_port_capability(xhci, portnum, XHCI_HLC)) {
 			udev->usb2_hw_lpm_capable = 1;
 			ret = xhci_set_usb2_hardware_lpm(hcd, udev, 1);
 			if (!ret)
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1548,6 +1548,9 @@ struct xhci_hcd {
 	unsigned		sw_lpm_support:1;
 	/* support xHCI 1.0 spec USB2 hardware LPM */
 	unsigned		hw_lpm_support:1;
+	/* cached usb2 extened protocol capabilites */
+	u32                     *ext_caps;
+	unsigned int            num_ext_caps;
 	/* Compliance Mode Recovery Data */
 	struct timer_list	comp_mode_recovery_timer;
 	u32			port_status_u0;