1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Samsung Exynos USB HOST EHCI Controller 4 * 5 * Copyright (C) 2011 Samsung Electronics Co.Ltd 6 * Author: Jingoo Han <jg1.han@samsung.com> 7 * Author: Joonyoung Shim <jy0922.shim@samsung.com> 8 */ 9 10 #include <linux/clk.h> 11 #include <linux/dma-mapping.h> 12 #include <linux/io.h> 13 #include <linux/kernel.h> 14 #include <linux/module.h> 15 #include <linux/of.h> 16 #include <linux/of_gpio.h> 17 #include <linux/phy/phy.h> 18 #include <linux/platform_device.h> 19 #include <linux/usb.h> 20 #include <linux/usb/hcd.h> 21 22 #include "ehci.h" 23 24 #define DRIVER_DESC "EHCI Exynos driver" 25 26 #define EHCI_INSNREG00(base) (base + 0x90) 27 #define EHCI_INSNREG00_ENA_INCR16 (0x1 << 25) 28 #define EHCI_INSNREG00_ENA_INCR8 (0x1 << 24) 29 #define EHCI_INSNREG00_ENA_INCR4 (0x1 << 23) 30 #define EHCI_INSNREG00_ENA_INCRX_ALIGN (0x1 << 22) 31 #define EHCI_INSNREG00_ENABLE_DMA_BURST \ 32 (EHCI_INSNREG00_ENA_INCR16 | EHCI_INSNREG00_ENA_INCR8 | \ 33 EHCI_INSNREG00_ENA_INCR4 | EHCI_INSNREG00_ENA_INCRX_ALIGN) 34 35 static const char hcd_name[] = "ehci-exynos"; 36 static struct hc_driver __read_mostly exynos_ehci_hc_driver; 37 38 #define PHY_NUMBER 3 39 40 struct exynos_ehci_hcd { 41 struct clk *clk; 42 struct device_node *of_node; 43 struct phy *phy[PHY_NUMBER]; 44 bool legacy_phy; 45 }; 46 47 #define to_exynos_ehci(hcd) (struct exynos_ehci_hcd *)(hcd_to_ehci(hcd)->priv) 48 49 static int exynos_ehci_get_phy(struct device *dev, 50 struct exynos_ehci_hcd *exynos_ehci) 51 { 52 struct device_node *child; 53 struct phy *phy; 54 int phy_number, num_phys; 55 int ret; 56 57 /* Get PHYs for the controller */ 58 num_phys = of_count_phandle_with_args(dev->of_node, "phys", 59 "#phy-cells"); 60 for (phy_number = 0; phy_number < num_phys; phy_number++) { 61 phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number); 62 if (IS_ERR(phy)) 63 return PTR_ERR(phy); 64 exynos_ehci->phy[phy_number] = phy; 65 } 66 if (num_phys > 0) 67 return 0; 68 69 /* Get PHYs using legacy bindings */ 70 for_each_available_child_of_node(dev->of_node, child) { 71 ret = of_property_read_u32(child, "reg", &phy_number); 72 if (ret) { 73 dev_err(dev, "Failed to parse device tree\n"); 74 of_node_put(child); 75 return ret; 76 } 77 78 if (phy_number >= PHY_NUMBER) { 79 dev_err(dev, "Invalid number of PHYs\n"); 80 of_node_put(child); 81 return -EINVAL; 82 } 83 84 phy = devm_of_phy_get(dev, child, NULL); 85 exynos_ehci->phy[phy_number] = phy; 86 if (IS_ERR(phy)) { 87 ret = PTR_ERR(phy); 88 if (ret == -EPROBE_DEFER) { 89 of_node_put(child); 90 return ret; 91 } else if (ret != -ENOSYS && ret != -ENODEV) { 92 dev_err(dev, 93 "Error retrieving usb2 phy: %d\n", ret); 94 of_node_put(child); 95 return ret; 96 } 97 } 98 } 99 100 exynos_ehci->legacy_phy = true; 101 return 0; 102 } 103 104 static int exynos_ehci_phy_enable(struct device *dev) 105 { 106 struct usb_hcd *hcd = dev_get_drvdata(dev); 107 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 108 int i; 109 int ret = 0; 110 111 for (i = 0; ret == 0 && i < PHY_NUMBER; i++) 112 if (!IS_ERR(exynos_ehci->phy[i])) 113 ret = phy_power_on(exynos_ehci->phy[i]); 114 if (ret) 115 for (i--; i >= 0; i--) 116 if (!IS_ERR(exynos_ehci->phy[i])) 117 phy_power_off(exynos_ehci->phy[i]); 118 119 return ret; 120 } 121 122 static void exynos_ehci_phy_disable(struct device *dev) 123 { 124 struct usb_hcd *hcd = dev_get_drvdata(dev); 125 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 126 int i; 127 128 for (i = 0; i < PHY_NUMBER; i++) 129 if (!IS_ERR(exynos_ehci->phy[i])) 130 phy_power_off(exynos_ehci->phy[i]); 131 } 132 133 static void exynos_setup_vbus_gpio(struct device *dev) 134 { 135 int err; 136 int gpio; 137 138 if (!dev->of_node) 139 return; 140 141 gpio = of_get_named_gpio(dev->of_node, "samsung,vbus-gpio", 0); 142 if (!gpio_is_valid(gpio)) 143 return; 144 145 err = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH, 146 "ehci_vbus_gpio"); 147 if (err) 148 dev_err(dev, "can't request ehci vbus gpio %d", gpio); 149 } 150 151 static int exynos_ehci_probe(struct platform_device *pdev) 152 { 153 struct exynos_ehci_hcd *exynos_ehci; 154 struct usb_hcd *hcd; 155 struct ehci_hcd *ehci; 156 struct resource *res; 157 int irq; 158 int err; 159 160 /* 161 * Right now device-tree probed devices don't get dma_mask set. 162 * Since shared usb code relies on it, set it here for now. 163 * Once we move to full device tree support this will vanish off. 164 */ 165 err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); 166 if (err) 167 return err; 168 169 exynos_setup_vbus_gpio(&pdev->dev); 170 171 hcd = usb_create_hcd(&exynos_ehci_hc_driver, 172 &pdev->dev, dev_name(&pdev->dev)); 173 if (!hcd) { 174 dev_err(&pdev->dev, "Unable to create HCD\n"); 175 return -ENOMEM; 176 } 177 exynos_ehci = to_exynos_ehci(hcd); 178 179 err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci); 180 if (err) 181 goto fail_clk; 182 183 exynos_ehci->clk = devm_clk_get(&pdev->dev, "usbhost"); 184 185 if (IS_ERR(exynos_ehci->clk)) { 186 dev_err(&pdev->dev, "Failed to get usbhost clock\n"); 187 err = PTR_ERR(exynos_ehci->clk); 188 goto fail_clk; 189 } 190 191 err = clk_prepare_enable(exynos_ehci->clk); 192 if (err) 193 goto fail_clk; 194 195 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 196 hcd->regs = devm_ioremap_resource(&pdev->dev, res); 197 if (IS_ERR(hcd->regs)) { 198 err = PTR_ERR(hcd->regs); 199 goto fail_io; 200 } 201 202 hcd->rsrc_start = res->start; 203 hcd->rsrc_len = resource_size(res); 204 205 irq = platform_get_irq(pdev, 0); 206 if (irq < 0) { 207 err = irq; 208 goto fail_io; 209 } 210 211 err = exynos_ehci_phy_enable(&pdev->dev); 212 if (err) { 213 dev_err(&pdev->dev, "Failed to enable USB phy\n"); 214 goto fail_io; 215 } 216 217 ehci = hcd_to_ehci(hcd); 218 ehci->caps = hcd->regs; 219 220 /* 221 * Workaround: reset of_node pointer to avoid conflict between legacy 222 * Exynos EHCI port subnodes and generic USB device bindings 223 */ 224 exynos_ehci->of_node = pdev->dev.of_node; 225 if (exynos_ehci->legacy_phy) 226 pdev->dev.of_node = NULL; 227 228 /* DMA burst Enable */ 229 writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs)); 230 231 err = usb_add_hcd(hcd, irq, IRQF_SHARED); 232 if (err) { 233 dev_err(&pdev->dev, "Failed to add USB HCD\n"); 234 goto fail_add_hcd; 235 } 236 device_wakeup_enable(hcd->self.controller); 237 238 platform_set_drvdata(pdev, hcd); 239 240 return 0; 241 242 fail_add_hcd: 243 exynos_ehci_phy_disable(&pdev->dev); 244 pdev->dev.of_node = exynos_ehci->of_node; 245 fail_io: 246 clk_disable_unprepare(exynos_ehci->clk); 247 fail_clk: 248 usb_put_hcd(hcd); 249 return err; 250 } 251 252 static int exynos_ehci_remove(struct platform_device *pdev) 253 { 254 struct usb_hcd *hcd = platform_get_drvdata(pdev); 255 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 256 257 pdev->dev.of_node = exynos_ehci->of_node; 258 259 usb_remove_hcd(hcd); 260 261 exynos_ehci_phy_disable(&pdev->dev); 262 263 clk_disable_unprepare(exynos_ehci->clk); 264 265 usb_put_hcd(hcd); 266 267 return 0; 268 } 269 270 #ifdef CONFIG_PM 271 static int exynos_ehci_suspend(struct device *dev) 272 { 273 struct usb_hcd *hcd = dev_get_drvdata(dev); 274 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 275 276 bool do_wakeup = device_may_wakeup(dev); 277 int rc; 278 279 rc = ehci_suspend(hcd, do_wakeup); 280 if (rc) 281 return rc; 282 283 exynos_ehci_phy_disable(dev); 284 285 clk_disable_unprepare(exynos_ehci->clk); 286 287 return rc; 288 } 289 290 static int exynos_ehci_resume(struct device *dev) 291 { 292 struct usb_hcd *hcd = dev_get_drvdata(dev); 293 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 294 int ret; 295 296 ret = clk_prepare_enable(exynos_ehci->clk); 297 if (ret) 298 return ret; 299 300 ret = exynos_ehci_phy_enable(dev); 301 if (ret) { 302 dev_err(dev, "Failed to enable USB phy\n"); 303 clk_disable_unprepare(exynos_ehci->clk); 304 return ret; 305 } 306 307 /* DMA burst Enable */ 308 writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs)); 309 310 ehci_resume(hcd, false); 311 return 0; 312 } 313 #else 314 #define exynos_ehci_suspend NULL 315 #define exynos_ehci_resume NULL 316 #endif 317 318 static const struct dev_pm_ops exynos_ehci_pm_ops = { 319 .suspend = exynos_ehci_suspend, 320 .resume = exynos_ehci_resume, 321 }; 322 323 #ifdef CONFIG_OF 324 static const struct of_device_id exynos_ehci_match[] = { 325 { .compatible = "samsung,exynos4210-ehci" }, 326 {}, 327 }; 328 MODULE_DEVICE_TABLE(of, exynos_ehci_match); 329 #endif 330 331 static struct platform_driver exynos_ehci_driver = { 332 .probe = exynos_ehci_probe, 333 .remove = exynos_ehci_remove, 334 .shutdown = usb_hcd_platform_shutdown, 335 .driver = { 336 .name = "exynos-ehci", 337 .pm = &exynos_ehci_pm_ops, 338 .of_match_table = of_match_ptr(exynos_ehci_match), 339 } 340 }; 341 static const struct ehci_driver_overrides exynos_overrides __initconst = { 342 .extra_priv_size = sizeof(struct exynos_ehci_hcd), 343 }; 344 345 static int __init ehci_exynos_init(void) 346 { 347 if (usb_disabled()) 348 return -ENODEV; 349 350 pr_info("%s: " DRIVER_DESC "\n", hcd_name); 351 ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides); 352 return platform_driver_register(&exynos_ehci_driver); 353 } 354 module_init(ehci_exynos_init); 355 356 static void __exit ehci_exynos_cleanup(void) 357 { 358 platform_driver_unregister(&exynos_ehci_driver); 359 } 360 module_exit(ehci_exynos_cleanup); 361 362 MODULE_DESCRIPTION(DRIVER_DESC); 363 MODULE_ALIAS("platform:exynos-ehci"); 364 MODULE_AUTHOR("Jingoo Han"); 365 MODULE_AUTHOR("Joonyoung Shim"); 366 MODULE_LICENSE("GPL v2"); 367