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 phy 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 phy driver for the
mux.
Signed-off-by: Hans de Goede <hdego...@redhat.com>
---
drivers/usb/host/Makefile | 2 +-
drivers/usb/host/xhci-ext-caps.h | 4 ++
drivers/usb/host/xhci-intel-cap.c | 90 +++++++++++++++++++++++++++++++++++++++
drivers/usb/host/xhci-pci.c | 4 ++
4 files changed, 99 insertions(+), 1 deletion(-)
create mode 100644 drivers/usb/host/xhci-intel-cap.c
diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index 6ef785b..e7c6d78 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -65,7 +65,7 @@ obj-$(CONFIG_USB_OHCI_HCD_PXA27X) += ohci-pxa27x.o
obj-$(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-cap.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-ext-caps.h b/drivers/usb/host/xhci-ext-caps.h
index e0244fb..456b6e2 100644
--- a/drivers/usb/host/xhci-ext-caps.h
+++ b/drivers/usb/host/xhci-ext-caps.h
@@ -90,6 +90,10 @@
#include <linux/io.h>
+struct xhci_hcd;
+
+int xhci_intel_cap_init(struct xhci_hcd *xhci);
+
/**
* Find the offset of the extended capabilities with capability ID id.
*
diff --git a/drivers/usb/host/xhci-intel-cap.c
b/drivers/usb/host/xhci-intel-cap.c
new file mode 100644
index 0000000..d655680
--- /dev/null
+++ b/drivers/usb/host/xhci-intel-cap.c
@@ -0,0 +1,90 @@
+/*
+ * Intel Vendor Defined XHCI extended capability handling
+ *
+ * Copyright (c) 2016) Hans de Goede <hdego...@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_intel_cap_init(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)
+ return -ENODEV;
+
+ /*
+ * If the Intel extended cap is present we create a platform device
+ * with its mmio region as resource, and let the phy driver handle it.
+ */
+ pdev = platform_device_alloc("intel_cht_usb_phy", PLATFORM_DEVID_AUTO);
+ if (!pdev) {
+ xhci_err(xhci, "couldn't allocate intel_cht_usb_phy pdev\n");
+ return -ENOMEM;
+ }
+
+ res.start = hcd->rsrc_start + ext_offset;
+ res.end = res.start + 0x3ff;
+ res.name = "intel_cht_usb_phy";
+ 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_phy
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_phy 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_phy pdev\n");
+ return ret;
+ }
+
+ xhci_info(xhci, "Intel Vendor Defined Cap %d found, added
intel_cht_usb_phy pdev\n",
+ XHCI_EXT_CAPS_INTEL_HOST_CAP);
+
+ return 0;
+}
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index e96ae80..c96b0b1 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -72,6 +72,10 @@ static int xhci_pci_reinit(struct xhci_hcd *xhci, struct
pci_dev *pdev)
* new extended capabilities.
*/
+ /* Init Intel vendor defined extended capability */
+ if (pdev->vendor == PCI_VENDOR_ID_INTEL)
+ xhci_intel_cap_init(xhci);
+
/* PCI Memory-Write-Invalidate cycle support is optional (uncommon) */
if (!pci_set_mwi(pdev))
xhci_dbg(xhci, "MWI active\n");
--
2.9.3
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