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 hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res); 177 if (IS_ERR(hcd->regs)) { 178 err = PTR_ERR(hcd->regs); 179 goto fail_io; 180 } 181 182 hcd->rsrc_start = res->start; 183 hcd->rsrc_len = resource_size(res); 184 185 irq = platform_get_irq(pdev, 0); 186 if (irq < 0) { 187 err = irq; 188 goto fail_io; 189 } 190 191 err = exynos_ehci_phy_enable(&pdev->dev); 192 if (err) { 193 dev_err(&pdev->dev, "Failed to enable USB phy\n"); 194 goto fail_io; 195 } 196 197 ehci = hcd_to_ehci(hcd); 198 ehci->caps = hcd->regs; 199 200 /* 201 * Workaround: reset of_node pointer to avoid conflict between legacy 202 * Exynos EHCI port subnodes and generic USB device bindings 203 */ 204 exynos_ehci->of_node = pdev->dev.of_node; 205 if (exynos_ehci->legacy_phy) 206 pdev->dev.of_node = NULL; 207 208 /* DMA burst Enable */ 209 writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs)); 210 211 err = usb_add_hcd(hcd, irq, IRQF_SHARED); 212 if (err) { 213 dev_err(&pdev->dev, "Failed to add USB HCD\n"); 214 goto fail_add_hcd; 215 } 216 device_wakeup_enable(hcd->self.controller); 217 218 platform_set_drvdata(pdev, hcd); 219 220 return 0; 221 222 fail_add_hcd: 223 exynos_ehci_phy_disable(&pdev->dev); 224 pdev->dev.of_node = exynos_ehci->of_node; 225 fail_io: 226 clk_disable_unprepare(exynos_ehci->clk); 227 fail_clk: 228 usb_put_hcd(hcd); 229 return err; 230 } 231 232 static void exynos_ehci_remove(struct platform_device *pdev) 233 { 234 struct usb_hcd *hcd = platform_get_drvdata(pdev); 235 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 236 237 pdev->dev.of_node = exynos_ehci->of_node; 238 239 usb_remove_hcd(hcd); 240 241 exynos_ehci_phy_disable(&pdev->dev); 242 243 clk_disable_unprepare(exynos_ehci->clk); 244 245 usb_put_hcd(hcd); 246 } 247 248 #ifdef CONFIG_PM 249 static int exynos_ehci_suspend(struct device *dev) 250 { 251 struct usb_hcd *hcd = dev_get_drvdata(dev); 252 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 253 254 bool do_wakeup = device_may_wakeup(dev); 255 int rc; 256 257 rc = ehci_suspend(hcd, do_wakeup); 258 if (rc) 259 return rc; 260 261 exynos_ehci_phy_disable(dev); 262 263 clk_disable_unprepare(exynos_ehci->clk); 264 265 return rc; 266 } 267 268 static int exynos_ehci_resume(struct device *dev) 269 { 270 struct usb_hcd *hcd = dev_get_drvdata(dev); 271 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 272 int ret; 273 274 ret = clk_prepare_enable(exynos_ehci->clk); 275 if (ret) 276 return ret; 277 278 ret = exynos_ehci_phy_enable(dev); 279 if (ret) { 280 dev_err(dev, "Failed to enable USB phy\n"); 281 clk_disable_unprepare(exynos_ehci->clk); 282 return ret; 283 } 284 285 /* DMA burst Enable */ 286 writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs)); 287 288 ehci_resume(hcd, false); 289 return 0; 290 } 291 #else 292 #define exynos_ehci_suspend NULL 293 #define exynos_ehci_resume NULL 294 #endif 295 296 static const struct dev_pm_ops exynos_ehci_pm_ops = { 297 .suspend = exynos_ehci_suspend, 298 .resume = exynos_ehci_resume, 299 }; 300 301 #ifdef CONFIG_OF 302 static const struct of_device_id exynos_ehci_match[] = { 303 { .compatible = "samsung,exynos4210-ehci" }, 304 {}, 305 }; 306 MODULE_DEVICE_TABLE(of, exynos_ehci_match); 307 #endif 308 309 static struct platform_driver exynos_ehci_driver = { 310 .probe = exynos_ehci_probe, 311 .remove_new = exynos_ehci_remove, 312 .shutdown = usb_hcd_platform_shutdown, 313 .driver = { 314 .name = "exynos-ehci", 315 .pm = &exynos_ehci_pm_ops, 316 .of_match_table = of_match_ptr(exynos_ehci_match), 317 } 318 }; 319 static const struct ehci_driver_overrides exynos_overrides __initconst = { 320 .extra_priv_size = sizeof(struct exynos_ehci_hcd), 321 }; 322 323 static int __init ehci_exynos_init(void) 324 { 325 if (usb_disabled()) 326 return -ENODEV; 327 328 ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides); 329 return platform_driver_register(&exynos_ehci_driver); 330 } 331 module_init(ehci_exynos_init); 332 333 static void __exit ehci_exynos_cleanup(void) 334 { 335 platform_driver_unregister(&exynos_ehci_driver); 336 } 337 module_exit(ehci_exynos_cleanup); 338 339 MODULE_DESCRIPTION(DRIVER_DESC); 340 MODULE_ALIAS("platform:exynos-ehci"); 341 MODULE_AUTHOR("Jingoo Han"); 342 MODULE_AUTHOR("Joonyoung Shim"); 343 MODULE_LICENSE("GPL v2"); 344