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.
Note this commit adds a call to the new xhci_ext_cap_init() function
to xhci_pci_probe(), it is added here because xhci_ext_cap_init() must
be called only once. If in the future we also want to handle ext-caps
on non pci XHCI HCDs from xhci_ext_cap_init() a call to it should also
be added to other bus probe paths.
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
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
Changes in v3:
-Add a new generic xhci_ext_cap_init() function and handle the new
XHCI_INTEL_CHT_USB_MUX quirk there.
---
drivers/usb/host/Makefile | 2 +-
drivers/usb/host/xhci-ext-caps.c | 88 ++++++++++++++++++++++++++++++++++++++++
drivers/usb/host/xhci-ext-caps.h | 2 +
drivers/usb/host/xhci-pci.c | 5 +++
drivers/usb/host/xhci.h | 2 +
5 files changed, 98 insertions(+), 1 deletion(-)
create mode 100644 drivers/usb/host/xhci-ext-caps.c
diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index cf2691fffcc0..59329a9cf392 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -10,7 +10,7 @@ fhci-y += fhci-mem.o fhci-tds.o fhci-sched.o
fhci-$(CONFIG_FHCI_DEBUG) += fhci-dbg.o
-xhci-hcd-y := xhci.o xhci-mem.o
+xhci-hcd-y := xhci.o xhci-mem.o xhci-ext-caps.o
xhci-hcd-y += xhci-ring.o xhci-hub.o xhci-dbg.o
xhci-hcd-y += xhci-trace.o
ifneq ($(CONFIG_USB_XHCI_MTK), )
diff --git a/drivers/usb/host/xhci-ext-caps.c b/drivers/usb/host/xhci-ext-caps.c
new file mode 100644
index 000000000000..8bc4787afdd0
--- /dev/null
+++ b/drivers/usb/host/xhci-ext-caps.c
@@ -0,0 +1,88 @@
+/*
+ * XHCI extended capability handling
+ *
+ * Copyright (c) 2017 Hans de Goede <hdegoede@xxxxxxxxxx>
+ *
+ * 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.
+ */
+
+#include <linux/platform_device.h>
+#include "xhci.h"
+
+static void xhci_intel_unregister_pdev(void *arg)
+{
+ platform_device_unregister(arg);
+}
+
+static int xhci_create_intel_cht_mux_pdev(struct xhci_hcd *xhci, u32 cap_offset)
+{
+ struct usb_hcd *hcd = xhci_to_hcd(xhci);
+ struct device *dev = hcd->self.controller;
+ struct platform_device *pdev;
+ struct resource res = { 0, };
+ int ret;
+
+ 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 + cap_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;
+}
+
+int xhci_ext_cap_init(struct xhci_hcd *xhci)
+{
+ void __iomem *base = &xhci->cap_regs->hc_capbase;
+ u32 cap_offset, val;
+ int ret;
+
+ cap_offset = xhci_find_next_ext_cap(base, 0, 0);
+
+ while (cap_offset) {
+ val = readl(base + cap_offset);
+
+ switch (XHCI_EXT_CAPS_ID(val)) {
+ case XHCI_EXT_CAPS_VENDOR_INTEL:
+ if (xhci->quirks & XHCI_INTEL_CHT_USB_MUX) {
+ ret = xhci_create_intel_cht_mux_pdev(
+ xhci, cap_offset);
+ if (ret)
+ return ret;
+ }
+ break;
+ }
+ cap_offset = xhci_find_next_ext_cap(base, cap_offset, 0);
+ }
+
+ return 0;
+}
diff --git a/drivers/usb/host/xhci-ext-caps.h b/drivers/usb/host/xhci-ext-caps.h
index c1b404224839..872fbec1347f 100644
--- a/drivers/usb/host/xhci-ext-caps.h
+++ b/drivers/usb/host/xhci-ext-caps.h
@@ -51,6 +51,8 @@
#define XHCI_EXT_CAPS_ROUTE 5
/* IDs 6-9 reserved */
#define XHCI_EXT_CAPS_DEBUG 10
+/* Vendor caps */
+#define XHCI_EXT_CAPS_VENDOR_INTEL 192
/* USB Legacy Support Capability - section 7.1.1 */
#define XHCI_HC_BIOS_OWNED (1 << 16)
#define XHCI_HC_OS_OWNED (1 << 24)
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 8071c8fdd15e..f088c5012503 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 ||
@@ -315,6 +316,10 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
goto dealloc_usb2_hcd;
}
+ retval = xhci_ext_cap_init(xhci);
+ if (retval)
+ goto put_usb3_hcd;
+
retval = usb_add_hcd(xhci->shared_hcd, dev->irq,
IRQF_SHARED);
if (retval)
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 2abaa4d6d39d..0b3ed0044b4d 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1828,6 +1828,7 @@ 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;
@@ -2012,6 +2013,7 @@ 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_ext_cap_init(struct xhci_hcd *xhci);
int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup);
int xhci_resume(struct xhci_hcd *xhci, bool hibernated);
--
2.14.1
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
