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