mfd: omap-usb-host: Add device tree support and binding information

Allows the OMAP HS USB host controller to be specified
via device tree.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 155 insertions, 6 deletions

diff --git a/drivers/mfd/omap-usb-host.c b/drivers/mfd/omap-usb-host.c
index 138ee982996c..d3b6e9491b62 100644
--- a/drivers/mfd/omap-usb-host.c
+++ b/drivers/mfd/omap-usb-host.c
@@ -1,8 +1,9 @@
 /**
  * omap-usb-host.c - The USBHS core driver for OMAP EHCI & OHCI
  *
- * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com
+ * Copyright (C) 2011-2013 Texas Instruments Incorporated - http://www.ti.com
  * Author: Keshava Munegowda <keshava_mgowda@ti.com>
+ * Author: Roger Quadros <rogerq@ti.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2  of
@@ -27,6 +28,8 @@
 #include <linux/platform_device.h>
 #include <linux/platform_data/usb-omap.h>
 #include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
 
 #include "omap-usb.h"
 
@@ -137,6 +140,49 @@ static inline u8 usbhs_readb(void __iomem *base, u8 reg)
 
 /*-------------------------------------------------------------------------*/
 
+/**
+ * Map 'enum usbhs_omap_port_mode' found in <linux/platform_data/usb-omap.h>
+ * to the device tree binding portN-mode found in
+ * 'Documentation/devicetree/bindings/mfd/omap-usb-host.txt'
+ */
+static const char * const port_modes[] = {
+        [OMAP_USBHS_PORT_MODE_UNUSED]   = "",
+        [OMAP_EHCI_PORT_MODE_PHY]       = "ehci-phy",
+        [OMAP_EHCI_PORT_MODE_TLL]       = "ehci-tll",
+        [OMAP_EHCI_PORT_MODE_HSIC]      = "ehci-hsic",
+        [OMAP_OHCI_PORT_MODE_PHY_6PIN_DATSE0]   = "ohci-phy-6pin-datse0",
+        [OMAP_OHCI_PORT_MODE_PHY_6PIN_DPDM]     = "ohci-phy-6pin-dpdm",
+        [OMAP_OHCI_PORT_MODE_PHY_3PIN_DATSE0]   = "ohci-phy-3pin-datse0",
+        [OMAP_OHCI_PORT_MODE_PHY_4PIN_DPDM]     = "ohci-phy-4pin-dpdm",
+        [OMAP_OHCI_PORT_MODE_TLL_6PIN_DATSE0]   = "ohci-tll-6pin-datse0",
+        [OMAP_OHCI_PORT_MODE_TLL_6PIN_DPDM]     = "ohci-tll-6pin-dpdm",
+        [OMAP_OHCI_PORT_MODE_TLL_3PIN_DATSE0]   = "ohci-tll-3pin-datse0",
+        [OMAP_OHCI_PORT_MODE_TLL_4PIN_DPDM]     = "ohci-tll-4pin-dpdm",
+        [OMAP_OHCI_PORT_MODE_TLL_2PIN_DATSE0]   = "ohci-tll-2pin-datse0",
+        [OMAP_OHCI_PORT_MODE_TLL_2PIN_DPDM]     = "ohci-tll-2pin-dpdm",
+};
+
+/**
+ * omap_usbhs_get_dt_port_mode - Get the 'enum usbhs_omap_port_mode'
+ * from the port mode string.
+ * @mode: The port mode string, usually obtained from device tree.
+ *
+ * The function returns the 'enum usbhs_omap_port_mode' that matches the
+ * provided port mode string as per the port_modes table.
+ * If no match is found it returns -ENODEV
+ */
+static const int omap_usbhs_get_dt_port_mode(const char *mode)
+{
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(port_modes); i++) {
+                if (!strcmp(mode, port_modes[i]))
+                        return i;
+        }
+
+        return -ENODEV;
+}
+
 static struct platform_device *omap_usbhs_alloc_child(const char *name,
                         struct resource *res, int num_resources, void *pdata,
                         size_t pdata_size, struct device *dev)
@@ -464,6 +510,58 @@ static void omap_usbhs_init(struct device *dev)
         pm_runtime_put_sync(dev);
 }
 
+static int usbhs_omap_get_dt_pdata(struct device *dev,
+                                        struct usbhs_omap_platform_data *pdata)
+{
+        int ret, i;
+        struct device_node *node = dev->of_node;
+
+        ret = of_property_read_u32(node, "num-ports", &pdata->nports);
+        if (ret)
+                pdata->nports = 0;
+
+        if (pdata->nports > OMAP3_HS_USB_PORTS) {
+                dev_warn(dev, "Too many num_ports <%d> in device tree. Max %d\n",
+                                pdata->nports, OMAP3_HS_USB_PORTS);
+                return -ENODEV;
+        }
+
+        /* get port modes */
+        for (i = 0; i < OMAP3_HS_USB_PORTS; i++) {
+                char prop[11];
+                const char *mode;
+
+                pdata->port_mode[i] = OMAP_USBHS_PORT_MODE_UNUSED;
+
+                snprintf(prop, sizeof(prop), "port%d-mode", i + 1);
+                ret = of_property_read_string(node, prop, &mode);
+                if (ret < 0)
+                        continue;
+
+                ret = omap_usbhs_get_dt_port_mode(mode);
+                if (ret < 0) {
+                        dev_warn(dev, "Invalid port%d-mode \"%s\" in device tree\n",
+                                        i, mode);
+                        return -ENODEV;
+                }
+
+                dev_dbg(dev, "port%d-mode: %s -> %d\n", i, mode, ret);
+                pdata->port_mode[i] = ret;
+        }
+
+        /* get flags */
+        pdata->single_ulpi_bypass = of_property_read_bool(node,
+                                                "single-ulpi-bypass");
+
+        return 0;
+}
+
+static struct of_device_id usbhs_child_match_table[] = {
+        { .compatible = "ti,omap-ehci", },
+        { .compatible = "ti,omap-ohci", },
+        { }
+};
+
 /**
  * usbhs_omap_probe - initialize TI-based HCDs
  *
@@ -479,18 +577,37 @@ static int usbhs_omap_probe(struct platform_device *pdev)
         int                             i;
         bool                            need_logic_fck;
 
+        if (dev->of_node) {
+                /* For DT boot we populate platform data from OF node */
+                pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+                if (!pdata)
+                        return -ENOMEM;
+
+                ret = usbhs_omap_get_dt_pdata(dev, pdata);
+                if (ret)
+                        return ret;
+
+                dev->platform_data = pdata;
+        }
+
         if (!pdata) {
                 dev_err(dev, "Missing platform data\n");
                 return -ENODEV;
         }
 
+        if (pdata->nports > OMAP3_HS_USB_PORTS) {
+                dev_info(dev, "Too many num_ports <%d> in platform_data. Max %d\n",
+                                pdata->nports, OMAP3_HS_USB_PORTS);
+                return -ENODEV;
+        }
+
         omap = devm_kzalloc(dev, sizeof(*omap), GFP_KERNEL);
         if (!omap) {
                 dev_err(dev, "Memory allocation failed\n");
                 return -ENOMEM;
         }
 
-        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "uhh");
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         omap->uhh_base = devm_request_and_ioremap(dev, res);
         if (!omap->uhh_base) {
                 dev_err(dev, "Resource request/ioremap failed\n");
@@ -661,10 +778,23 @@ static int usbhs_omap_probe(struct platform_device *pdev)
         }
 
         omap_usbhs_init(dev);
-        ret = omap_usbhs_alloc_children(pdev);
-        if (ret) {
-                dev_err(dev, "omap_usbhs_alloc_children failed\n");
-                goto err_alloc;
+
+        if (dev->of_node) {
+                ret = of_platform_populate(dev->of_node,
+                                usbhs_child_match_table, NULL, dev);
+
+                if (ret) {
+                        dev_err(dev, "Failed to create DT children: %d\n", ret);
+                        goto err_alloc;
+                }
+
+        } else {
+                ret = omap_usbhs_alloc_children(pdev);
+                if (ret) {
+                        dev_err(dev, "omap_usbhs_alloc_children failed: %d\n",
+                                                ret);
+                        goto err_alloc;
+                }
         }
 
         return 0;
@@ -703,6 +833,13 @@ err_mem:
         return ret;
 }
 
+static int usbhs_omap_remove_child(struct device *dev, void *data)
+{
+        dev_info(dev, "unregistering\n");
+        platform_device_unregister(to_platform_device(dev));
+        return 0;
+}
+
 /**
  * usbhs_omap_remove - shutdown processing for UHH & TLL HCDs
  * @pdev: USB Host Controller being removed
@@ -734,6 +871,8 @@ static int usbhs_omap_remove(struct platform_device *pdev)
 
         pm_runtime_disable(&pdev->dev);
 
+        /* remove children */
+        device_for_each_child(&pdev->dev, NULL, usbhs_omap_remove_child);
         return 0;
 }
 
@@ -742,16 +881,26 @@ static const struct dev_pm_ops usbhsomap_dev_pm_ops = {
         .runtime_resume         = usbhs_runtime_resume,
 };
 
+static const struct of_device_id usbhs_omap_dt_ids[] = {
+        { .compatible = "ti,usbhs-host" },
+        { }
+};
+
+MODULE_DEVICE_TABLE(of, usbhs_omap_dt_ids);
+
+
 static struct platform_driver usbhs_omap_driver = {
         .driver = {
                 .name           = (char *)usbhs_driver_name,
                 .owner          = THIS_MODULE,
                 .pm             = &usbhsomap_dev_pm_ops,
+                .of_match_table = of_match_ptr(usbhs_omap_dt_ids),
         },
         .remove         = usbhs_omap_remove,
 };
 
 MODULE_AUTHOR("Keshava Munegowda <keshava_mgowda@ti.com>");
+MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
 MODULE_ALIAS("platform:" USBHS_DRIVER_NAME);
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("usb host common core driver for omap EHCI and OHCI");