[PATCH 04/11] usb: xhci: Add Intel cherrytrail extended cap / otg phy mux handling

[Hans de Goede <hdegoede@redhat.com>]

The Intel cherrytrail xhci controller has an extended cap mmio-range
which contains registers to control the muxing to the xhci (host mode)
or the dwc3 (device mode) and vbus-detection for the otg usb-phy.

Having a mux driver included in the xhci code (or under drivers/usb/host)
is not desirable. So this commit adds a simple handler for this extended
capability, which creates a platform device with the caps mmio region as
resource, this allows us to write a separate platform mux driver for the
mux.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v2:
-Check xHCI controller PCI device-id instead of only checking for the
 Intel Extended capability ID, as the Extended capability ID is used on
 other model Intel xHCI controllers too
---
 drivers/usb/host/Makefile            |  2 +-
 drivers/usb/host/xhci-intel-quirks.c | 85 ++++++++++++++++++++++++++++++++++++
 drivers/usb/host/xhci-pci.c          |  4 ++
 drivers/usb/host/xhci.h              |  2 +
 4 files changed, 92 insertions(+), 1 deletion(-)
 create mode 100644 drivers/usb/host/xhci-intel-quirks.c

diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index cf2691fffcc0..441edf82eb1c 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -63,7 +63,7 @@ obj-$(CONFIG_USB_OHCI_HCD_DAVINCI)	+= ohci-da8xx.o
 obj-$(CONFIG_USB_UHCI_HCD)	+= uhci-hcd.o
 obj-$(CONFIG_USB_FHCI_HCD)	+= fhci.o
 obj-$(CONFIG_USB_XHCI_HCD)	+= xhci-hcd.o
-obj-$(CONFIG_USB_XHCI_PCI)	+= xhci-pci.o
+obj-$(CONFIG_USB_XHCI_PCI)	+= xhci-pci.o xhci-intel-quirks.o
 obj-$(CONFIG_USB_XHCI_PLATFORM) += xhci-plat-hcd.o
 obj-$(CONFIG_USB_XHCI_MTK)	+= xhci-mtk.o
 obj-$(CONFIG_USB_XHCI_TEGRA)	+= xhci-tegra.o
diff --git a/drivers/usb/host/xhci-intel-quirks.c b/drivers/usb/host/xhci-intel-quirks.c
new file mode 100644
index 000000000000..819f5f9da9ee
--- /dev/null
+++ b/drivers/usb/host/xhci-intel-quirks.c
@@ -0,0 +1,85 @@
+/*
+ * Intel Vendor Defined XHCI extended capability handling
+ *
+ * Copyright (c) 2016) Hans de Goede <hdegoede@redhat.com>
+ *
+ * Loosely based on android x86 kernel code which is:
+ *
+ * Copyright (C) 2014 Intel Corp.
+ *
+ * Author: Wu, Hao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program;
+ */
+
+#include <linux/platform_device.h>
+#include "xhci.h"
+
+/* Extended capability IDs for Intel Vendor Defined */
+#define XHCI_EXT_CAPS_INTEL_HOST_CAP	192
+
+static void xhci_intel_unregister_pdev(void *arg)
+{
+	platform_device_unregister(arg);
+}
+
+int xhci_create_intel_cht_mux_pdev(struct xhci_hcd *xhci)
+{
+	struct usb_hcd *hcd = xhci_to_hcd(xhci);
+	struct device *dev = hcd->self.controller;
+	struct platform_device *pdev;
+	struct resource	res = { 0, };
+	int ret, ext_offset;
+
+	ext_offset = xhci_find_next_ext_cap(&xhci->cap_regs->hc_capbase, 0,
+					    XHCI_EXT_CAPS_INTEL_HOST_CAP);
+	if (!ext_offset) {
+		xhci_err(xhci, "couldn't find Intel ext caps\n");
+		return -ENODEV;
+	}
+
+	pdev = platform_device_alloc("intel_cht_usb_mux", PLATFORM_DEVID_NONE);
+	if (!pdev) {
+		xhci_err(xhci, "couldn't allocate intel_cht_usb_mux pdev\n");
+		return -ENOMEM;
+	}
+
+	res.start = hcd->rsrc_start + ext_offset;
+	res.end	  = res.start + 0x3ff;
+	res.name  = "intel_cht_usb_mux";
+	res.flags = IORESOURCE_MEM;
+
+	ret = platform_device_add_resources(pdev, &res, 1);
+	if (ret) {
+		dev_err(dev, "couldn't add resources to intel_cht_usb_mux pdev\n");
+		platform_device_put(pdev);
+		return ret;
+	}
+
+	pdev->dev.parent = dev;
+
+	ret = platform_device_add(pdev);
+	if (ret) {
+		dev_err(dev, "couldn't register intel_cht_usb_mux pdev\n");
+		platform_device_put(pdev);
+		return ret;
+	}
+
+	ret = devm_add_action_or_reset(dev, xhci_intel_unregister_pdev, pdev);
+	if (ret) {
+		dev_err(dev, "couldn't add unregister action for intel_cht_usb_mux pdev\n");
+		return ret;
+	}
+
+	return 0;
+}
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 8071c8fdd15e..b55c1e96abf0 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -188,6 +188,7 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
 		 pdev->device == PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI) {
 		xhci->quirks |= XHCI_SSIC_PORT_UNUSED;
+		xhci->quirks |= XHCI_INTEL_CHT_USB_MUX;
 	}
 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
 	    (pdev->device == PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI ||
@@ -328,6 +329,9 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	if (xhci->quirks & XHCI_PME_STUCK_QUIRK)
 		xhci_pme_acpi_rtd3_enable(dev);
 
+	if (xhci->quirks & XHCI_INTEL_CHT_USB_MUX)
+		xhci_create_intel_cht_mux_pdev(xhci);
+
 	/* USB-2 and USB-3 roothubs initialized, allow runtime pm suspend */
 	pm_runtime_put_noidle(&dev->dev);
 
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index e3e935291ed6..f722ee31e50d 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1821,6 +1821,7 @@ struct xhci_hcd {
 #define XHCI_LIMIT_ENDPOINT_INTERVAL_7	(1 << 26)
 #define XHCI_U2_DISABLE_WAKE	(1 << 27)
 #define XHCI_ASMEDIA_MODIFY_FLOWCONTROL	(1 << 28)
+#define XHCI_INTEL_CHT_USB_MUX	(1 << 29)
 
 	unsigned int		num_active_eps;
 	unsigned int		limit_active_eps;
@@ -2005,6 +2006,7 @@ void xhci_init_driver(struct hc_driver *drv,
 		      const struct xhci_driver_overrides *over);
 int xhci_disable_slot(struct xhci_hcd *xhci,
 			struct xhci_command *command, u32 slot_id);
+int xhci_create_intel_cht_mux_pdev(struct xhci_hcd *xhci);
 
 int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup);
 int xhci_resume(struct xhci_hcd *xhci, bool hibernated);
-- 
2.13.5