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