drivers/usb/fotg210/fotg210-core.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Central probing code for the FOTG210 dual role driver
   4  * We register one driver for the hardware and then we decide
   5  * whether to proceed with probing the host or the peripheral
   6  * driver.
   7  */
   8 #include <linux/bitops.h>
   9 #include <linux/clk.h>
  10 #include <linux/device.h>
  11 #include <linux/mfd/syscon.h>
  12 #include <linux/module.h>
  13 #include <linux/of.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/regmap.h>
  16 #include <linux/usb.h>
  17 #include <linux/usb/otg.h>
  18
  19 #include "fotg210.h"
  20
  21 /* Role Register 0x80 */
  22 #define FOTG210_RR                      0x80
  23 #define FOTG210_RR_ID                   BIT(21) /* 1 = B-device, 0 = A-device */
  24 #define FOTG210_RR_CROLE                BIT(20) /* 1 = device, 0 = host */
  25
  26 /*
  27  * Gemini-specific initialization function, only executed on the
  28  * Gemini SoC using the global misc control register.
  29  *
  30  * The gemini USB blocks are connected to either Mini-A (host mode) or
  31  * Mini-B (peripheral mode) plugs. There is no role switch support on the
  32  * Gemini SoC, just either-or.
  33  */
  34 #define GEMINI_GLOBAL_MISC_CTRL         0x30
  35 #define GEMINI_MISC_USB0_WAKEUP         BIT(14)
  36 #define GEMINI_MISC_USB1_WAKEUP         BIT(15)
  37 #define GEMINI_MISC_USB0_VBUS_ON        BIT(22)
  38 #define GEMINI_MISC_USB1_VBUS_ON        BIT(23)
  39 #define GEMINI_MISC_USB0_MINI_B         BIT(29)
  40 #define GEMINI_MISC_USB1_MINI_B         BIT(30)
  41
  42 static int fotg210_gemini_init(struct fotg210 *fotg, struct resource *res,
  43                                enum usb_dr_mode mode)
  44 {
  45         struct device *dev = fotg->dev;
  46         struct device_node *np = dev->of_node;
  47         struct regmap *map;
  48         bool wakeup;
  49         u32 mask, val;
  50         int ret;
  51
  52         map = syscon_regmap_lookup_by_phandle(np, "syscon");
  53         if (IS_ERR(map))
  54                 return dev_err_probe(dev, PTR_ERR(map), "no syscon\n");
  55         fotg->map = map;
  56         wakeup = of_property_read_bool(np, "wakeup-source");
  57
  58         /*
  59          * Figure out if this is USB0 or USB1 by simply checking the
  60          * physical base address.
  61          */
  62         mask = 0;
  63         if (res->start == 0x69000000) {
  64                 fotg->port = GEMINI_PORT_1;
  65                 mask = GEMINI_MISC_USB1_VBUS_ON | GEMINI_MISC_USB1_MINI_B |
  66                         GEMINI_MISC_USB1_WAKEUP;
  67                 if (mode == USB_DR_MODE_HOST)
  68                         val = GEMINI_MISC_USB1_VBUS_ON;
  69                 else
  70                         val = GEMINI_MISC_USB1_MINI_B;
  71                 if (wakeup)
  72                         val |= GEMINI_MISC_USB1_WAKEUP;
  73         } else {
  74                 fotg->port = GEMINI_PORT_0;
  75                 mask = GEMINI_MISC_USB0_VBUS_ON | GEMINI_MISC_USB0_MINI_B |
  76                         GEMINI_MISC_USB0_WAKEUP;
  77                 if (mode == USB_DR_MODE_HOST)
  78                         val = GEMINI_MISC_USB0_VBUS_ON;
  79                 else
  80                         val = GEMINI_MISC_USB0_MINI_B;
  81                 if (wakeup)
  82                         val |= GEMINI_MISC_USB0_WAKEUP;
  83         }
  84
  85         ret = regmap_update_bits(map, GEMINI_GLOBAL_MISC_CTRL, mask, val);
  86         if (ret) {
  87                 dev_err(dev, "failed to initialize Gemini PHY\n");
  88                 return ret;
  89         }
  90
  91         dev_info(dev, "initialized Gemini PHY in %s mode\n",
  92                  (mode == USB_DR_MODE_HOST) ? "host" : "gadget");
  93         return 0;
  94 }
  95
  96 /**
  97  * fotg210_vbus() - Called by gadget driver to enable/disable VBUS
  98  * @fotg: pointer to a private fotg210 object
  99  * @enable: true to enable VBUS, false to disable VBUS
 100  */
 101 void fotg210_vbus(struct fotg210 *fotg, bool enable)
 102 {
 103         u32 mask;
 104         u32 val;
 105         int ret;
 106
 107         switch (fotg->port) {
 108         case GEMINI_PORT_0:
 109                 mask = GEMINI_MISC_USB0_VBUS_ON;
 110                 val = enable ? GEMINI_MISC_USB0_VBUS_ON : 0;
 111                 break;
 112         case GEMINI_PORT_1:
 113                 mask = GEMINI_MISC_USB1_VBUS_ON;
 114                 val = enable ? GEMINI_MISC_USB1_VBUS_ON : 0;
 115                 break;
 116         default:
 117                 return;
 118         }
 119         ret = regmap_update_bits(fotg->map, GEMINI_GLOBAL_MISC_CTRL, mask, val);
 120         if (ret)
 121                 dev_err(fotg->dev, "failed to %s VBUS\n",
 122                         enable ? "enable" : "disable");
 123         dev_info(fotg->dev, "%s: %s VBUS\n", __func__, enable ? "enable" : "disable");
 124 }
 125
 126 static int fotg210_probe(struct platform_device *pdev)
 127 {
 128         struct device *dev = &pdev->dev;
 129         enum usb_dr_mode mode;
 130         struct fotg210 *fotg;
 131         u32 val;
 132         int ret;
 133
 134         fotg = devm_kzalloc(dev, sizeof(*fotg), GFP_KERNEL);
 135         if (!fotg)
 136                 return -ENOMEM;
 137         fotg->dev = dev;
 138
 139         fotg->base = devm_platform_get_and_ioremap_resource(pdev, 0, &fotg->res);
 140         if (IS_ERR(fotg->base))
 141                 return PTR_ERR(fotg->base);
 142
 143         fotg->pclk = devm_clk_get_optional_enabled(dev, "PCLK");
 144         if (IS_ERR(fotg->pclk))
 145                 return PTR_ERR(fotg->pclk);
 146
 147         mode = usb_get_dr_mode(dev);
 148
 149         if (of_device_is_compatible(dev->of_node, "cortina,gemini-usb")) {
 150                 ret = fotg210_gemini_init(fotg, fotg->res, mode);
 151                 if (ret)
 152                         return ret;
 153         }
 154
 155         val = readl(fotg->base + FOTG210_RR);
 156         if (mode == USB_DR_MODE_PERIPHERAL) {
 157                 if (!(val & FOTG210_RR_CROLE))
 158                         dev_err(dev, "block not in device role\n");
 159                 ret = fotg210_udc_probe(pdev, fotg);
 160         } else {
 161                 if (val & FOTG210_RR_CROLE)
 162                         dev_err(dev, "block not in host role\n");
 163                 ret = fotg210_hcd_probe(pdev, fotg);
 164         }
 165
 166         return ret;
 167 }
 168
 169 static void fotg210_remove(struct platform_device *pdev)
 170 {
 171         struct device *dev = &pdev->dev;
 172         enum usb_dr_mode mode;
 173
 174         mode = usb_get_dr_mode(dev);
 175
 176         if (mode == USB_DR_MODE_PERIPHERAL)
 177                 fotg210_udc_remove(pdev);
 178         else
 179                 fotg210_hcd_remove(pdev);
 180 }
 181
 182 #ifdef CONFIG_OF
 183 static const struct of_device_id fotg210_of_match[] = {
 184         { .compatible = "faraday,fotg200" },
 185         { .compatible = "faraday,fotg210" },
 186         /* TODO: can we also handle FUSB220? */
 187         {},
 188 };
 189 MODULE_DEVICE_TABLE(of, fotg210_of_match);
 190 #endif
 191
 192 static struct platform_driver fotg210_driver = {
 193         .driver = {
 194                 .name   = "fotg210",
 195                 .of_match_table = of_match_ptr(fotg210_of_match),
 196         },
 197         .probe  = fotg210_probe,
 198         .remove = fotg210_remove,
 199 };
 200
 201 static int __init fotg210_init(void)
 202 {
 203         if (IS_ENABLED(CONFIG_USB_FOTG210_HCD) && !usb_disabled())
 204                 fotg210_hcd_init();
 205         return platform_driver_register(&fotg210_driver);
 206 }
 207 module_init(fotg210_init);
 208
 209 static void __exit fotg210_cleanup(void)
 210 {
 211         platform_driver_unregister(&fotg210_driver);
 212         if (IS_ENABLED(CONFIG_USB_FOTG210_HCD))
 213                 fotg210_hcd_cleanup();
 214 }
 215 module_exit(fotg210_cleanup);
 216
 217 MODULE_AUTHOR("Yuan-Hsin Chen, Feng-Hsin Chiang");
 218 MODULE_LICENSE("GPL");
 219 MODULE_DESCRIPTION("FOTG210 Dual Role Controller Driver");