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