1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * SAMSUNG EXYNOS USB HOST OHCI Controller 4 * 5 * Copyright (C) 2011 Samsung Electronics Co.Ltd 6 * Author: Jingoo Han <jg1.han@samsung.com> 7 */ 8 9 #include <linux/clk.h> 10 #include <linux/dma-mapping.h> 11 #include <linux/io.h> 12 #include <linux/kernel.h> 13 #include <linux/module.h> 14 #include <linux/of.h> 15 #include <linux/platform_device.h> 16 #include <linux/phy/phy.h> 17 #include <linux/usb.h> 18 #include <linux/usb/hcd.h> 19 20 #include "ohci.h" 21 22 #define DRIVER_DESC "OHCI EXYNOS driver" 23 24 static const char hcd_name[] = "ohci-exynos"; 25 static struct hc_driver __read_mostly exynos_ohci_hc_driver; 26 27 #define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv) 28 29 #define PHY_NUMBER 3 30 31 struct exynos_ohci_hcd { 32 struct clk *clk; 33 struct device_node *of_node; 34 struct phy *phy[PHY_NUMBER]; 35 bool legacy_phy; 36 }; 37 38 static int exynos_ohci_get_phy(struct device *dev, 39 struct exynos_ohci_hcd *exynos_ohci) 40 { 41 struct device_node *child; 42 struct phy *phy; 43 int phy_number, num_phys; 44 int ret; 45 46 /* Get PHYs for the controller */ 47 num_phys = of_count_phandle_with_args(dev->of_node, "phys", 48 "#phy-cells"); 49 for (phy_number = 0; phy_number < num_phys; phy_number++) { 50 phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number); 51 if (IS_ERR(phy)) 52 return PTR_ERR(phy); 53 exynos_ohci->phy[phy_number] = phy; 54 } 55 if (num_phys > 0) 56 return 0; 57 58 /* Get PHYs using legacy bindings */ 59 for_each_available_child_of_node(dev->of_node, child) { 60 ret = of_property_read_u32(child, "reg", &phy_number); 61 if (ret) { 62 dev_err(dev, "Failed to parse device tree\n"); 63 of_node_put(child); 64 return ret; 65 } 66 67 if (phy_number >= PHY_NUMBER) { 68 dev_err(dev, "Invalid number of PHYs\n"); 69 of_node_put(child); 70 return -EINVAL; 71 } 72 73 phy = devm_of_phy_get(dev, child, NULL); 74 exynos_ohci->phy[phy_number] = phy; 75 if (IS_ERR(phy)) { 76 ret = PTR_ERR(phy); 77 if (ret == -EPROBE_DEFER) { 78 of_node_put(child); 79 return ret; 80 } else if (ret != -ENOSYS && ret != -ENODEV) { 81 dev_err(dev, 82 "Error retrieving usb2 phy: %d\n", ret); 83 of_node_put(child); 84 return ret; 85 } 86 } 87 } 88 89 exynos_ohci->legacy_phy = true; 90 return 0; 91 } 92 93 static int exynos_ohci_phy_enable(struct device *dev) 94 { 95 struct usb_hcd *hcd = dev_get_drvdata(dev); 96 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd); 97 int i; 98 int ret = 0; 99 100 for (i = 0; ret == 0 && i < PHY_NUMBER; i++) 101 if (!IS_ERR(exynos_ohci->phy[i])) 102 ret = phy_power_on(exynos_ohci->phy[i]); 103 if (ret) 104 for (i--; i >= 0; i--) 105 if (!IS_ERR(exynos_ohci->phy[i])) 106 phy_power_off(exynos_ohci->phy[i]); 107 108 return ret; 109 } 110 111 static void exynos_ohci_phy_disable(struct device *dev) 112 { 113 struct usb_hcd *hcd = dev_get_drvdata(dev); 114 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd); 115 int i; 116 117 for (i = 0; i < PHY_NUMBER; i++) 118 if (!IS_ERR(exynos_ohci->phy[i])) 119 phy_power_off(exynos_ohci->phy[i]); 120 } 121 122 static int exynos_ohci_probe(struct platform_device *pdev) 123 { 124 struct exynos_ohci_hcd *exynos_ohci; 125 struct usb_hcd *hcd; 126 struct resource *res; 127 int irq; 128 int err; 129 130 /* 131 * Right now device-tree probed devices don't get dma_mask set. 132 * Since shared usb code relies on it, set it here for now. 133 * Once we move to full device tree support this will vanish off. 134 */ 135 err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); 136 if (err) 137 return err; 138 139 hcd = usb_create_hcd(&exynos_ohci_hc_driver, 140 &pdev->dev, dev_name(&pdev->dev)); 141 if (!hcd) { 142 dev_err(&pdev->dev, "Unable to create HCD\n"); 143 return -ENOMEM; 144 } 145 146 exynos_ohci = to_exynos_ohci(hcd); 147 148 err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci); 149 if (err) 150 goto fail_clk; 151 152 exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost"); 153 154 if (IS_ERR(exynos_ohci->clk)) { 155 dev_err(&pdev->dev, "Failed to get usbhost clock\n"); 156 err = PTR_ERR(exynos_ohci->clk); 157 goto fail_clk; 158 } 159 160 err = clk_prepare_enable(exynos_ohci->clk); 161 if (err) 162 goto fail_clk; 163 164 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 165 hcd->regs = devm_ioremap_resource(&pdev->dev, res); 166 if (IS_ERR(hcd->regs)) { 167 err = PTR_ERR(hcd->regs); 168 goto fail_io; 169 } 170 hcd->rsrc_start = res->start; 171 hcd->rsrc_len = resource_size(res); 172 173 irq = platform_get_irq(pdev, 0); 174 if (!irq) { 175 dev_err(&pdev->dev, "Failed to get IRQ\n"); 176 err = -ENODEV; 177 goto fail_io; 178 } 179 180 platform_set_drvdata(pdev, hcd); 181 182 err = exynos_ohci_phy_enable(&pdev->dev); 183 if (err) { 184 dev_err(&pdev->dev, "Failed to enable USB phy\n"); 185 goto fail_io; 186 } 187 188 /* 189 * Workaround: reset of_node pointer to avoid conflict between legacy 190 * Exynos OHCI port subnodes and generic USB device bindings 191 */ 192 exynos_ohci->of_node = pdev->dev.of_node; 193 if (exynos_ohci->legacy_phy) 194 pdev->dev.of_node = NULL; 195 196 err = usb_add_hcd(hcd, irq, IRQF_SHARED); 197 if (err) { 198 dev_err(&pdev->dev, "Failed to add USB HCD\n"); 199 goto fail_add_hcd; 200 } 201 device_wakeup_enable(hcd->self.controller); 202 return 0; 203 204 fail_add_hcd: 205 exynos_ohci_phy_disable(&pdev->dev); 206 pdev->dev.of_node = exynos_ohci->of_node; 207 fail_io: 208 clk_disable_unprepare(exynos_ohci->clk); 209 fail_clk: 210 usb_put_hcd(hcd); 211 return err; 212 } 213 214 static int exynos_ohci_remove(struct platform_device *pdev) 215 { 216 struct usb_hcd *hcd = platform_get_drvdata(pdev); 217 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd); 218 219 pdev->dev.of_node = exynos_ohci->of_node; 220 221 usb_remove_hcd(hcd); 222 223 exynos_ohci_phy_disable(&pdev->dev); 224 225 clk_disable_unprepare(exynos_ohci->clk); 226 227 usb_put_hcd(hcd); 228 229 return 0; 230 } 231 232 static void exynos_ohci_shutdown(struct platform_device *pdev) 233 { 234 struct usb_hcd *hcd = platform_get_drvdata(pdev); 235 236 if (hcd->driver->shutdown) 237 hcd->driver->shutdown(hcd); 238 } 239 240 #ifdef CONFIG_PM 241 static int exynos_ohci_suspend(struct device *dev) 242 { 243 struct usb_hcd *hcd = dev_get_drvdata(dev); 244 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd); 245 bool do_wakeup = device_may_wakeup(dev); 246 int rc = ohci_suspend(hcd, do_wakeup); 247 248 if (rc) 249 return rc; 250 251 exynos_ohci_phy_disable(dev); 252 253 clk_disable_unprepare(exynos_ohci->clk); 254 255 return 0; 256 } 257 258 static int exynos_ohci_resume(struct device *dev) 259 { 260 struct usb_hcd *hcd = dev_get_drvdata(dev); 261 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd); 262 int ret; 263 264 clk_prepare_enable(exynos_ohci->clk); 265 266 ret = exynos_ohci_phy_enable(dev); 267 if (ret) { 268 dev_err(dev, "Failed to enable USB phy\n"); 269 clk_disable_unprepare(exynos_ohci->clk); 270 return ret; 271 } 272 273 ohci_resume(hcd, false); 274 275 return 0; 276 } 277 #else 278 #define exynos_ohci_suspend NULL 279 #define exynos_ohci_resume NULL 280 #endif 281 282 static const struct ohci_driver_overrides exynos_overrides __initconst = { 283 .extra_priv_size = sizeof(struct exynos_ohci_hcd), 284 }; 285 286 static const struct dev_pm_ops exynos_ohci_pm_ops = { 287 .suspend = exynos_ohci_suspend, 288 .resume = exynos_ohci_resume, 289 }; 290 291 #ifdef CONFIG_OF 292 static const struct of_device_id exynos_ohci_match[] = { 293 { .compatible = "samsung,exynos4210-ohci" }, 294 {}, 295 }; 296 MODULE_DEVICE_TABLE(of, exynos_ohci_match); 297 #endif 298 299 static struct platform_driver exynos_ohci_driver = { 300 .probe = exynos_ohci_probe, 301 .remove = exynos_ohci_remove, 302 .shutdown = exynos_ohci_shutdown, 303 .driver = { 304 .name = "exynos-ohci", 305 .pm = &exynos_ohci_pm_ops, 306 .of_match_table = of_match_ptr(exynos_ohci_match), 307 } 308 }; 309 static int __init ohci_exynos_init(void) 310 { 311 if (usb_disabled()) 312 return -ENODEV; 313 314 pr_info("%s: " DRIVER_DESC "\n", hcd_name); 315 ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides); 316 return platform_driver_register(&exynos_ohci_driver); 317 } 318 module_init(ohci_exynos_init); 319 320 static void __exit ohci_exynos_cleanup(void) 321 { 322 platform_driver_unregister(&exynos_ohci_driver); 323 } 324 module_exit(ohci_exynos_cleanup); 325 326 MODULE_ALIAS("platform:exynos-ohci"); 327 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>"); 328 MODULE_LICENSE("GPL v2"); 329