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_io; 163 164 exynos_ehci->clk = devm_clk_get_enabled(&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_io; 170 } 171 172 hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res); 173 if (IS_ERR(hcd->regs)) { 174 err = PTR_ERR(hcd->regs); 175 goto fail_io; 176 } 177 178 hcd->rsrc_start = res->start; 179 hcd->rsrc_len = resource_size(res); 180 181 irq = platform_get_irq(pdev, 0); 182 if (irq < 0) { 183 err = irq; 184 goto fail_io; 185 } 186 187 err = exynos_ehci_phy_enable(&pdev->dev); 188 if (err) { 189 dev_err(&pdev->dev, "Failed to enable USB phy\n"); 190 goto fail_io; 191 } 192 193 ehci = hcd_to_ehci(hcd); 194 ehci->caps = hcd->regs; 195 196 /* 197 * Workaround: reset of_node pointer to avoid conflict between legacy 198 * Exynos EHCI port subnodes and generic USB device bindings 199 */ 200 exynos_ehci->of_node = pdev->dev.of_node; 201 if (exynos_ehci->legacy_phy) 202 pdev->dev.of_node = NULL; 203 204 /* DMA burst Enable */ 205 writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs)); 206 207 err = usb_add_hcd(hcd, irq, IRQF_SHARED); 208 if (err) { 209 dev_err(&pdev->dev, "Failed to add USB HCD\n"); 210 goto fail_add_hcd; 211 } 212 device_wakeup_enable(hcd->self.controller); 213 214 platform_set_drvdata(pdev, hcd); 215 216 return 0; 217 218 fail_add_hcd: 219 exynos_ehci_phy_disable(&pdev->dev); 220 pdev->dev.of_node = exynos_ehci->of_node; 221 fail_io: 222 usb_put_hcd(hcd); 223 return err; 224 } 225 226 static void exynos_ehci_remove(struct platform_device *pdev) 227 { 228 struct usb_hcd *hcd = platform_get_drvdata(pdev); 229 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 230 231 pdev->dev.of_node = exynos_ehci->of_node; 232 233 usb_remove_hcd(hcd); 234 235 exynos_ehci_phy_disable(&pdev->dev); 236 237 usb_put_hcd(hcd); 238 } 239 240 static int exynos_ehci_suspend(struct device *dev) 241 { 242 struct usb_hcd *hcd = dev_get_drvdata(dev); 243 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 244 245 bool do_wakeup = device_may_wakeup(dev); 246 int rc; 247 248 rc = ehci_suspend(hcd, do_wakeup); 249 if (rc) 250 return rc; 251 252 exynos_ehci_phy_disable(dev); 253 254 clk_disable_unprepare(exynos_ehci->clk); 255 256 return rc; 257 } 258 259 static int exynos_ehci_resume(struct device *dev) 260 { 261 struct usb_hcd *hcd = dev_get_drvdata(dev); 262 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd); 263 int ret; 264 265 ret = clk_prepare_enable(exynos_ehci->clk); 266 if (ret) 267 return ret; 268 269 ret = exynos_ehci_phy_enable(dev); 270 if (ret) { 271 dev_err(dev, "Failed to enable USB phy\n"); 272 clk_disable_unprepare(exynos_ehci->clk); 273 return ret; 274 } 275 276 /* DMA burst Enable */ 277 writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs)); 278 279 ehci_resume(hcd, false); 280 return 0; 281 } 282 283 static DEFINE_SIMPLE_DEV_PM_OPS(exynos_ehci_pm_ops, 284 exynos_ehci_suspend, exynos_ehci_resume); 285 286 #ifdef CONFIG_OF 287 static const struct of_device_id exynos_ehci_match[] = { 288 { .compatible = "samsung,exynos4210-ehci" }, 289 {}, 290 }; 291 MODULE_DEVICE_TABLE(of, exynos_ehci_match); 292 #endif 293 294 static struct platform_driver exynos_ehci_driver = { 295 .probe = exynos_ehci_probe, 296 .remove_new = exynos_ehci_remove, 297 .shutdown = usb_hcd_platform_shutdown, 298 .driver = { 299 .name = "exynos-ehci", 300 .pm = pm_ptr(&exynos_ehci_pm_ops), 301 .of_match_table = of_match_ptr(exynos_ehci_match), 302 } 303 }; 304 static const struct ehci_driver_overrides exynos_overrides __initconst = { 305 .extra_priv_size = sizeof(struct exynos_ehci_hcd), 306 }; 307 308 static int __init ehci_exynos_init(void) 309 { 310 if (usb_disabled()) 311 return -ENODEV; 312 313 ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides); 314 return platform_driver_register(&exynos_ehci_driver); 315 } 316 module_init(ehci_exynos_init); 317 318 static void __exit ehci_exynos_cleanup(void) 319 { 320 platform_driver_unregister(&exynos_ehci_driver); 321 } 322 module_exit(ehci_exynos_cleanup); 323 324 MODULE_DESCRIPTION(DRIVER_DESC); 325 MODULE_ALIAS("platform:exynos-ehci"); 326 MODULE_AUTHOR("Jingoo Han"); 327 MODULE_AUTHOR("Joonyoung Shim"); 328 MODULE_LICENSE("GPL v2"); 329