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 * @enable: true to enable VBUS, false to disable VBUS 99 */ 100 void fotg210_vbus(struct fotg210 *fotg, bool enable) 101 { 102 u32 mask; 103 u32 val; 104 int ret; 105 106 switch (fotg->port) { 107 case GEMINI_PORT_0: 108 mask = GEMINI_MISC_USB0_VBUS_ON; 109 val = enable ? GEMINI_MISC_USB0_VBUS_ON : 0; 110 break; 111 case GEMINI_PORT_1: 112 mask = GEMINI_MISC_USB1_VBUS_ON; 113 val = enable ? GEMINI_MISC_USB1_VBUS_ON : 0; 114 break; 115 default: 116 return; 117 } 118 ret = regmap_update_bits(fotg->map, GEMINI_GLOBAL_MISC_CTRL, mask, val); 119 if (ret) 120 dev_err(fotg->dev, "failed to %s VBUS\n", 121 enable ? "enable" : "disable"); 122 dev_info(fotg->dev, "%s: %s VBUS\n", __func__, enable ? "enable" : "disable"); 123 } 124 125 static int fotg210_probe(struct platform_device *pdev) 126 { 127 struct device *dev = &pdev->dev; 128 enum usb_dr_mode mode; 129 struct fotg210 *fotg; 130 u32 val; 131 int ret; 132 133 fotg = devm_kzalloc(dev, sizeof(*fotg), GFP_KERNEL); 134 if (!fotg) 135 return -ENOMEM; 136 fotg->dev = dev; 137 138 fotg->base = devm_platform_get_and_ioremap_resource(pdev, 0, &fotg->res); 139 if (IS_ERR(fotg->base)) 140 return PTR_ERR(fotg->base); 141 142 fotg->pclk = devm_clk_get_optional_enabled(dev, "PCLK"); 143 if (IS_ERR(fotg->pclk)) 144 return PTR_ERR(fotg->pclk); 145 146 mode = usb_get_dr_mode(dev); 147 148 if (of_device_is_compatible(dev->of_node, "cortina,gemini-usb")) { 149 ret = fotg210_gemini_init(fotg, fotg->res, mode); 150 if (ret) 151 return ret; 152 } 153 154 val = readl(fotg->base + FOTG210_RR); 155 if (mode == USB_DR_MODE_PERIPHERAL) { 156 if (!(val & FOTG210_RR_CROLE)) 157 dev_err(dev, "block not in device role\n"); 158 ret = fotg210_udc_probe(pdev, fotg); 159 } else { 160 if (val & FOTG210_RR_CROLE) 161 dev_err(dev, "block not in host role\n"); 162 ret = fotg210_hcd_probe(pdev, fotg); 163 } 164 165 return ret; 166 } 167 168 static int fotg210_remove(struct platform_device *pdev) 169 { 170 struct device *dev = &pdev->dev; 171 enum usb_dr_mode mode; 172 173 mode = usb_get_dr_mode(dev); 174 175 if (mode == USB_DR_MODE_PERIPHERAL) 176 fotg210_udc_remove(pdev); 177 else 178 fotg210_hcd_remove(pdev); 179 180 return 0; 181 } 182 183 #ifdef CONFIG_OF 184 static const struct of_device_id fotg210_of_match[] = { 185 { .compatible = "faraday,fotg200" }, 186 { .compatible = "faraday,fotg210" }, 187 /* TODO: can we also handle FUSB220? */ 188 {}, 189 }; 190 MODULE_DEVICE_TABLE(of, fotg210_of_match); 191 #endif 192 193 static struct platform_driver fotg210_driver = { 194 .driver = { 195 .name = "fotg210", 196 .of_match_table = of_match_ptr(fotg210_of_match), 197 }, 198 .probe = fotg210_probe, 199 .remove = fotg210_remove, 200 }; 201 202 static int __init fotg210_init(void) 203 { 204 if (IS_ENABLED(CONFIG_USB_FOTG210_HCD) && !usb_disabled()) 205 fotg210_hcd_init(); 206 return platform_driver_register(&fotg210_driver); 207 } 208 module_init(fotg210_init); 209 210 static void __exit fotg210_cleanup(void) 211 { 212 platform_driver_unregister(&fotg210_driver); 213 if (IS_ENABLED(CONFIG_USB_FOTG210_HCD)) 214 fotg210_hcd_cleanup(); 215 } 216 module_exit(fotg210_cleanup); 217 218 MODULE_AUTHOR("Yuan-Hsin Chen, Feng-Hsin Chiang"); 219 MODULE_LICENSE("GPL"); 220 MODULE_DESCRIPTION("FOTG210 Dual Role Controller Driver"); 221