USB: EHCI: Add MSM Host Controller driver

This patch adds support for EHCI compliant HSUSB Host controller found
on MSM chips. The root hub has a single port and TT is built into it.
This driver depends on OTG driver for PHY initialization, clock
management and powering up VBUS.

Signed-off-by: Pavankumar Kondeti <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/Kconfig

···
 	default y if ARCH_OMAP3
 	default y if ARCH_VT8500
 	default y if PLAT_SPEAR
+	default y if ARCH_MSM
 	default PCI
 
 # ARM SA1111 chips have a non-PCI based "OHCI-compatible" USB host interface.

drivers/usb/host/Kconfig

···
 	  Enables support for the on-chip EHCI controller on
 	  OMAP3 and later chips.
 
+config USB_EHCI_MSM
+	bool "Support for MSM on-chip EHCI USB controller"
+	depends on USB_EHCI_HCD && ARCH_MSM
+	select USB_EHCI_ROOT_HUB_TT
+	select USB_MSM_OTG_72K
+	---help---
+	  Enables support for the USB Host controller present on the
+	  Qualcomm chipsets. Root Hub has inbuilt TT.
+	  This driver depends on OTG driver for PHY initialization,
+	  clock management, powering up VBUS.
+
 config USB_EHCI_HCD_PPC_OF
 	bool "EHCI support for PPC USB controller on OF platform bus"
 	depends on USB_EHCI_HCD && PPC_OF

drivers/usb/host/ehci-hcd.c

···
 #define PLATFORM_DRIVER		spear_ehci_hcd_driver
 #endif
 
+#ifdef CONFIG_USB_EHCI_MSM
+#include "ehci-msm.c"
+#define PLATFORM_DRIVER		ehci_msm_driver
+#endif
+
 #if !defined(PCI_DRIVER) && !defined(PLATFORM_DRIVER) && \
     !defined(PS3_SYSTEM_BUS_DRIVER) && !defined(OF_PLATFORM_DRIVER) && \
     !defined(XILINX_OF_PLATFORM_DRIVER)

drivers/usb/host/ehci-msm.c

···
+/* ehci-msm.c - HSUSB Host Controller Driver Implementation
+ *
+ * Copyright (c) 2008-2010, Code Aurora Forum. All rights reserved.
+ *
+ * Partly derived from ehci-fsl.c and ehci-hcd.c
+ * Copyright (c) 2000-2004 by David Brownell
+ * Copyright (c) 2005 MontaVista Software
+ *
+ * All source code in this file is licensed under the following license except
+ * where indicated.
+ *
+ * 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; if not, you can find it at http://www.fsf.org
+ */
+
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+
+#include <linux/usb/otg.h>
+#include <linux/usb/msm_hsusb_hw.h>
+
+#define MSM_USB_BASE (hcd->regs)
+
+static struct otg_transceiver *otg;
+
+/*
+ * ehci_run defined in drivers/usb/host/ehci-hcd.c reset the controller and
+ * the configuration settings in ehci_msm_reset vanish after controller is
+ * reset. Resetting the controler in ehci_run seems to be un-necessary
+ * provided HCD reset the controller before calling ehci_run. Most of the HCD
+ * do but some are not. So this function is same as ehci_run but we don't
+ * reset the controller here.
+ */
+static int ehci_msm_run(struct usb_hcd *hcd)
+{
+	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);
+	u32			temp;
+	u32			hcc_params;
+
+	hcd->uses_new_polling = 1;
+
+	ehci_writel(ehci, ehci->periodic_dma, &ehci->regs->frame_list);
+	ehci_writel(ehci, (u32)ehci->async->qh_dma, &ehci->regs->async_next);
+
+	/*
+	 * hcc_params controls whether ehci->regs->segment must (!!!)
+	 * be used; it constrains QH/ITD/SITD and QTD locations.
+	 * pci_pool consistent memory always uses segment zero.
+	 * streaming mappings for I/O buffers, like pci_map_single(),
+	 * can return segments above 4GB, if the device allows.
+	 *
+	 * NOTE:  the dma mask is visible through dma_supported(), so
+	 * drivers can pass this info along ... like NETIF_F_HIGHDMA,
+	 * Scsi_Host.highmem_io, and so forth.  It's readonly to all
+	 * host side drivers though.
+	 */
+	hcc_params = ehci_readl(ehci, &ehci->caps->hcc_params);
+	if (HCC_64BIT_ADDR(hcc_params))
+		ehci_writel(ehci, 0, &ehci->regs->segment);
+
+	/*
+	 * Philips, Intel, and maybe others need CMD_RUN before the
+	 * root hub will detect new devices (why?); NEC doesn't
+	 */
+	ehci->command &= ~(CMD_LRESET|CMD_IAAD|CMD_PSE|CMD_ASE|CMD_RESET);
+	ehci->command |= CMD_RUN;
+	ehci_writel(ehci, ehci->command, &ehci->regs->command);
+	dbg_cmd(ehci, "init", ehci->command);
+
+	/*
+	 * Start, enabling full USB 2.0 functionality ... usb 1.1 devices
+	 * are explicitly handed to companion controller(s), so no TT is
+	 * involved with the root hub.  (Except where one is integrated,
+	 * and there's no companion controller unless maybe for USB OTG.)
+	 *
+	 * Turning on the CF flag will transfer ownership of all ports
+	 * from the companions to the EHCI controller.  If any of the
+	 * companions are in the middle of a port reset at the time, it
+	 * could cause trouble.  Write-locking ehci_cf_port_reset_rwsem
+	 * guarantees that no resets are in progress.  After we set CF,
+	 * a short delay lets the hardware catch up; new resets shouldn't
+	 * be started before the port switching actions could complete.
+	 */
+	down_write(&ehci_cf_port_reset_rwsem);
+	hcd->state = HC_STATE_RUNNING;
+	ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
+	ehci_readl(ehci, &ehci->regs->command);	/* unblock posted writes */
+	usleep_range(5000, 5500);
+	up_write(&ehci_cf_port_reset_rwsem);
+	ehci->last_periodic_enable = ktime_get_real();
+
+	temp = HC_VERSION(ehci_readl(ehci, &ehci->caps->hc_capbase));
+	ehci_info(ehci,
+		"USB %x.%x started, EHCI %x.%02x%s\n",
+		((ehci->sbrn & 0xf0)>>4), (ehci->sbrn & 0x0f),
+		temp >> 8, temp & 0xff,
+		ignore_oc ? ", overcurrent ignored" : "");
+
+	ehci_writel(ehci, INTR_MASK,
+		    &ehci->regs->intr_enable); /* Turn On Interrupts */
+
+	/* GRR this is run-once init(), being done every time the HC starts.
+	 * So long as they're part of class devices, we can't do it init()
+	 * since the class device isn't created that early.
+	 */
+	create_debug_files(ehci);
+	create_companion_file(ehci);
+
+	return 0;
+}
+
+static int ehci_msm_reset(struct usb_hcd *hcd)
+{
+	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+	int retval;
+
+	ehci->caps = USB_CAPLENGTH;
+	ehci->regs = USB_CAPLENGTH +
+		HC_LENGTH(ehci_readl(ehci, &ehci->caps->hc_capbase));
+
+	/* cache the data to minimize the chip reads*/
+	ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
+
+	hcd->has_tt = 1;
+	ehci->sbrn = HCD_USB2;
+
+	/* data structure init */
+	retval = ehci_init(hcd);
+	if (retval)
+		return retval;
+
+	retval = ehci_reset(ehci);
+	if (retval)
+		return retval;
+
+	/* bursts of unspecified length. */
+	writel(0, USB_AHBBURST);
+	/* Use the AHB transactor */
+	writel(0, USB_AHBMODE);
+	/* Disable streaming mode and select host mode */
+	writel(0x13, USB_USBMODE);
+
+	ehci_port_power(ehci, 1);
+	return 0;
+}
+
+static struct hc_driver msm_hc_driver = {
+	.description		= hcd_name,
+	.product_desc		= "Qualcomm On-Chip EHCI Host Controller",
+	.hcd_priv_size		= sizeof(struct ehci_hcd),
+
+	/*
+	 * generic hardware linkage
+	 */
+	.irq			= ehci_irq,
+	.flags			= HCD_USB2 | HCD_MEMORY,
+
+	.reset			= ehci_msm_reset,
+	.start			= ehci_msm_run,
+
+	.stop			= ehci_stop,
+	.shutdown		= ehci_shutdown,
+
+	/*
+	 * managing i/o requests and associated device resources
+	 */
+	.urb_enqueue		= ehci_urb_enqueue,
+	.urb_dequeue		= ehci_urb_dequeue,
+	.endpoint_disable	= ehci_endpoint_disable,
+	.endpoint_reset		= ehci_endpoint_reset,
+	.clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
+
+	/*
+	 * scheduling support
+	 */
+	.get_frame_number	= ehci_get_frame,
+
+	/*
+	 * root hub support
+	 */
+	.hub_status_data	= ehci_hub_status_data,
+	.hub_control		= ehci_hub_control,
+	.relinquish_port	= ehci_relinquish_port,
+	.port_handed_over	= ehci_port_handed_over,
+
+	/*
+	 * PM support
+	 */
+	.bus_suspend		= ehci_bus_suspend,
+	.bus_resume		= ehci_bus_resume,
+};
+
+static int ehci_msm_probe(struct platform_device *pdev)
+{
+	struct usb_hcd *hcd;
+	struct resource *res;
+	int ret;
+
+	dev_dbg(&pdev->dev, "ehci_msm proble\n");
+
+	hcd = usb_create_hcd(&msm_hc_driver, &pdev->dev, dev_name(&pdev->dev));
+	if (!hcd) {
+		dev_err(&pdev->dev, "Unable to create HCD\n");
+		return  -ENOMEM;
+	}
+
+	hcd->irq = platform_get_irq(pdev, 0);
+	if (hcd->irq < 0) {
+		dev_err(&pdev->dev, "Unable to get IRQ resource\n");
+		ret = hcd->irq;
+		goto put_hcd;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "Unable to get memory resource\n");
+		ret = -ENODEV;
+		goto put_hcd;
+	}
+
+	hcd->rsrc_start = res->start;
+	hcd->rsrc_len = resource_size(res);
+	hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
+	if (!hcd->regs) {
+		dev_err(&pdev->dev, "ioremap failed\n");
+		ret = -ENOMEM;
+		goto put_hcd;
+	}
+
+	/*
+	 * OTG driver takes care of PHY initialization, clock management,
+	 * powering up VBUS and mapping of registers address space.
+	 */
+	otg = otg_get_transceiver();
+	if (!otg) {
+		dev_err(&pdev->dev, "unable to find transceiver\n");
+		ret = -ENODEV;
+		goto unmap;
+	}
+
+	ret = otg_set_host(otg, &hcd->self);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "unable to register with transceiver\n");
+		goto put_transceiver;
+	}
+
+	device_init_wakeup(&pdev->dev, 1);
+	return 0;
+
+put_transceiver:
+	otg_put_transceiver(otg);
+unmap:
+	iounmap(hcd->regs);
+put_hcd:
+	usb_put_hcd(hcd);
+
+	return ret;
+}
+
+static int __devexit ehci_msm_remove(struct platform_device *pdev)
+{
+	struct usb_hcd *hcd = platform_get_drvdata(pdev);
+
+	device_init_wakeup(&pdev->dev, 0);
+
+	otg_set_host(otg, NULL);
+	otg_put_transceiver(otg);
+
+	usb_put_hcd(hcd);
+
+	return 0;
+}
+
+static struct platform_driver ehci_msm_driver = {
+	.probe	= ehci_msm_probe,
+	.remove	= __devexit_p(ehci_msm_remove),
+	.driver = {
+		   .name = "msm_hsusb_host",
+	},
+};