1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2016, NVIDIA Corporation 4 */ 5 6 #include <linux/clk.h> 7 #include <linux/io.h> 8 #include <linux/module.h> 9 #include <linux/of.h> 10 #include <linux/platform_device.h> 11 #include <linux/pm_runtime.h> 12 #include <linux/reset.h> 13 14 #include <linux/usb.h> 15 #include <linux/usb/chipidea.h> 16 #include <linux/usb/hcd.h> 17 #include <linux/usb/of.h> 18 #include <linux/usb/phy.h> 19 20 #include <soc/tegra/common.h> 21 22 #include "../host/ehci.h" 23 24 #include "ci.h" 25 26 struct tegra_usb { 27 struct ci_hdrc_platform_data data; 28 struct platform_device *dev; 29 30 const struct tegra_usb_soc_info *soc; 31 struct usb_phy *phy; 32 struct clk *clk; 33 34 bool needs_double_reset; 35 }; 36 37 struct tegra_usb_soc_info { 38 unsigned long flags; 39 unsigned int txfifothresh; 40 enum usb_dr_mode dr_mode; 41 }; 42 43 static const struct tegra_usb_soc_info tegra20_ehci_soc_info = { 44 .flags = CI_HDRC_REQUIRES_ALIGNED_DMA | 45 CI_HDRC_OVERRIDE_PHY_CONTROL | 46 CI_HDRC_SUPPORTS_RUNTIME_PM, 47 .dr_mode = USB_DR_MODE_HOST, 48 .txfifothresh = 10, 49 }; 50 51 static const struct tegra_usb_soc_info tegra30_ehci_soc_info = { 52 .flags = CI_HDRC_REQUIRES_ALIGNED_DMA | 53 CI_HDRC_OVERRIDE_PHY_CONTROL | 54 CI_HDRC_SUPPORTS_RUNTIME_PM, 55 .dr_mode = USB_DR_MODE_HOST, 56 .txfifothresh = 16, 57 }; 58 59 static const struct tegra_usb_soc_info tegra20_udc_soc_info = { 60 .flags = CI_HDRC_REQUIRES_ALIGNED_DMA | 61 CI_HDRC_OVERRIDE_PHY_CONTROL | 62 CI_HDRC_SUPPORTS_RUNTIME_PM, 63 .dr_mode = USB_DR_MODE_UNKNOWN, 64 .txfifothresh = 10, 65 }; 66 67 static const struct tegra_usb_soc_info tegra30_udc_soc_info = { 68 .flags = CI_HDRC_REQUIRES_ALIGNED_DMA | 69 CI_HDRC_OVERRIDE_PHY_CONTROL | 70 CI_HDRC_SUPPORTS_RUNTIME_PM, 71 .dr_mode = USB_DR_MODE_UNKNOWN, 72 .txfifothresh = 16, 73 }; 74 75 static const struct of_device_id tegra_usb_of_match[] = { 76 { 77 .compatible = "nvidia,tegra20-ehci", 78 .data = &tegra20_ehci_soc_info, 79 }, { 80 .compatible = "nvidia,tegra30-ehci", 81 .data = &tegra30_ehci_soc_info, 82 }, { 83 .compatible = "nvidia,tegra20-udc", 84 .data = &tegra20_udc_soc_info, 85 }, { 86 .compatible = "nvidia,tegra30-udc", 87 .data = &tegra30_udc_soc_info, 88 }, { 89 .compatible = "nvidia,tegra114-udc", 90 .data = &tegra30_udc_soc_info, 91 }, { 92 .compatible = "nvidia,tegra124-udc", 93 .data = &tegra30_udc_soc_info, 94 }, { 95 /* sentinel */ 96 } 97 }; 98 MODULE_DEVICE_TABLE(of, tegra_usb_of_match); 99 100 static int tegra_usb_reset_controller(struct device *dev) 101 { 102 struct reset_control *rst, *rst_utmi; 103 struct device_node *phy_np; 104 int err; 105 106 rst = devm_reset_control_get_shared(dev, "usb"); 107 if (IS_ERR(rst)) { 108 dev_err(dev, "can't get ehci reset: %pe\n", rst); 109 return PTR_ERR(rst); 110 } 111 112 phy_np = of_parse_phandle(dev->of_node, "nvidia,phy", 0); 113 if (!phy_np) 114 return -ENOENT; 115 116 /* 117 * The 1st USB controller contains some UTMI pad registers that are 118 * global for all the controllers on the chip. Those registers are 119 * also cleared when reset is asserted to the 1st controller. 120 */ 121 rst_utmi = of_reset_control_get_shared(phy_np, "utmi-pads"); 122 if (IS_ERR(rst_utmi)) { 123 dev_warn(dev, "can't get utmi-pads reset from the PHY\n"); 124 dev_warn(dev, "continuing, but please update your DT\n"); 125 } else { 126 /* 127 * PHY driver performs UTMI-pads reset in a case of a 128 * non-legacy DT. 129 */ 130 reset_control_put(rst_utmi); 131 } 132 133 of_node_put(phy_np); 134 135 /* reset control is shared, hence initialize it first */ 136 err = reset_control_deassert(rst); 137 if (err) 138 return err; 139 140 err = reset_control_assert(rst); 141 if (err) 142 return err; 143 144 udelay(1); 145 146 err = reset_control_deassert(rst); 147 if (err) 148 return err; 149 150 return 0; 151 } 152 153 static int tegra_usb_notify_event(struct ci_hdrc *ci, unsigned int event) 154 { 155 struct tegra_usb *usb = dev_get_drvdata(ci->dev->parent); 156 struct ehci_hcd *ehci; 157 158 switch (event) { 159 case CI_HDRC_CONTROLLER_RESET_EVENT: 160 if (ci->hcd) { 161 ehci = hcd_to_ehci(ci->hcd); 162 ehci->has_tdi_phy_lpm = false; 163 ehci_writel(ehci, usb->soc->txfifothresh << 16, 164 &ehci->regs->txfill_tuning); 165 } 166 break; 167 } 168 169 return 0; 170 } 171 172 static int tegra_usb_internal_port_reset(struct ehci_hcd *ehci, 173 u32 __iomem *portsc_reg, 174 unsigned long *flags) 175 { 176 u32 saved_usbintr, temp; 177 unsigned int i, tries; 178 int retval = 0; 179 180 saved_usbintr = ehci_readl(ehci, &ehci->regs->intr_enable); 181 /* disable USB interrupt */ 182 ehci_writel(ehci, 0, &ehci->regs->intr_enable); 183 spin_unlock_irqrestore(&ehci->lock, *flags); 184 185 /* 186 * Here we have to do Port Reset at most twice for 187 * Port Enable bit to be set. 188 */ 189 for (i = 0; i < 2; i++) { 190 temp = ehci_readl(ehci, portsc_reg); 191 temp |= PORT_RESET; 192 ehci_writel(ehci, temp, portsc_reg); 193 fsleep(10000); 194 temp &= ~PORT_RESET; 195 ehci_writel(ehci, temp, portsc_reg); 196 fsleep(1000); 197 tries = 100; 198 do { 199 fsleep(1000); 200 /* 201 * Up to this point, Port Enable bit is 202 * expected to be set after 2 ms waiting. 203 * USB1 usually takes extra 45 ms, for safety, 204 * we take 100 ms as timeout. 205 */ 206 temp = ehci_readl(ehci, portsc_reg); 207 } while (!(temp & PORT_PE) && tries--); 208 if (temp & PORT_PE) 209 break; 210 } 211 if (i == 2) 212 retval = -ETIMEDOUT; 213 214 /* 215 * Clear Connect Status Change bit if it's set. 216 * We can't clear PORT_PEC. It will also cause PORT_PE to be cleared. 217 */ 218 if (temp & PORT_CSC) 219 ehci_writel(ehci, PORT_CSC, portsc_reg); 220 221 /* 222 * Write to clear any interrupt status bits that might be set 223 * during port reset. 224 */ 225 temp = ehci_readl(ehci, &ehci->regs->status); 226 ehci_writel(ehci, temp, &ehci->regs->status); 227 228 /* restore original interrupt-enable bits */ 229 spin_lock_irqsave(&ehci->lock, *flags); 230 ehci_writel(ehci, saved_usbintr, &ehci->regs->intr_enable); 231 232 return retval; 233 } 234 235 static int tegra_ehci_hub_control(struct ci_hdrc *ci, u16 typeReq, u16 wValue, 236 u16 wIndex, char *buf, u16 wLength, 237 bool *done, unsigned long *flags) 238 { 239 struct tegra_usb *usb = dev_get_drvdata(ci->dev->parent); 240 struct ehci_hcd *ehci = hcd_to_ehci(ci->hcd); 241 u32 __iomem *status_reg; 242 int retval = 0; 243 244 status_reg = &ehci->regs->port_status[(wIndex & 0xff) - 1]; 245 246 switch (typeReq) { 247 case SetPortFeature: 248 if (wValue != USB_PORT_FEAT_RESET || !usb->needs_double_reset) 249 break; 250 251 /* for USB1 port we need to issue Port Reset twice internally */ 252 retval = tegra_usb_internal_port_reset(ehci, status_reg, flags); 253 *done = true; 254 break; 255 } 256 257 return retval; 258 } 259 260 static void tegra_usb_enter_lpm(struct ci_hdrc *ci, bool enable) 261 { 262 /* 263 * Touching any register which belongs to AHB clock domain will 264 * hang CPU if USB controller is put into low power mode because 265 * AHB USB clock is gated on Tegra in the LPM. 266 * 267 * Tegra PHY has a separate register for checking the clock status 268 * and usb_phy_set_suspend() takes care of gating/ungating the clocks 269 * and restoring the PHY state on Tegra. Hence DEVLC/PORTSC registers 270 * shouldn't be touched directly by the CI driver. 271 */ 272 usb_phy_set_suspend(ci->usb_phy, enable); 273 } 274 275 static int tegra_usb_probe(struct platform_device *pdev) 276 { 277 const struct tegra_usb_soc_info *soc; 278 struct tegra_usb *usb; 279 int err; 280 281 usb = devm_kzalloc(&pdev->dev, sizeof(*usb), GFP_KERNEL); 282 if (!usb) 283 return -ENOMEM; 284 285 platform_set_drvdata(pdev, usb); 286 287 soc = of_device_get_match_data(&pdev->dev); 288 if (!soc) { 289 dev_err(&pdev->dev, "failed to match OF data\n"); 290 return -EINVAL; 291 } 292 293 usb->phy = devm_usb_get_phy_by_phandle(&pdev->dev, "nvidia,phy", 0); 294 if (IS_ERR(usb->phy)) 295 return dev_err_probe(&pdev->dev, PTR_ERR(usb->phy), 296 "failed to get PHY"); 297 298 usb->clk = devm_clk_get(&pdev->dev, NULL); 299 if (IS_ERR(usb->clk)) 300 return dev_err_probe(&pdev->dev, PTR_ERR(usb->clk), 301 "failed to get clock"); 302 303 err = devm_tegra_core_dev_init_opp_table_common(&pdev->dev); 304 if (err) 305 return err; 306 307 pm_runtime_enable(&pdev->dev); 308 err = pm_runtime_resume_and_get(&pdev->dev); 309 if (err) 310 return err; 311 312 if (device_property_present(&pdev->dev, "nvidia,needs-double-reset")) 313 usb->needs_double_reset = true; 314 315 err = tegra_usb_reset_controller(&pdev->dev); 316 if (err) { 317 dev_err_probe(&pdev->dev, err, "failed to reset controller"); 318 goto fail_power_off; 319 } 320 321 /* 322 * USB controller registers shouldn't be touched before PHY is 323 * initialized, otherwise CPU will hang because clocks are gated. 324 * PHY driver controls gating of internal USB clocks on Tegra. 325 */ 326 err = usb_phy_init(usb->phy); 327 if (err) 328 goto fail_power_off; 329 330 /* setup and register ChipIdea HDRC device */ 331 usb->soc = soc; 332 usb->data.name = "tegra-usb"; 333 usb->data.flags = soc->flags; 334 usb->data.usb_phy = usb->phy; 335 usb->data.dr_mode = soc->dr_mode; 336 usb->data.capoffset = DEF_CAPOFFSET; 337 usb->data.enter_lpm = tegra_usb_enter_lpm; 338 usb->data.hub_control = tegra_ehci_hub_control; 339 usb->data.notify_event = tegra_usb_notify_event; 340 341 /* Tegra PHY driver currently doesn't support LPM for ULPI */ 342 if (of_usb_get_phy_mode(pdev->dev.of_node) == USBPHY_INTERFACE_MODE_ULPI) 343 usb->data.flags &= ~CI_HDRC_SUPPORTS_RUNTIME_PM; 344 345 usb->dev = ci_hdrc_add_device(&pdev->dev, pdev->resource, 346 pdev->num_resources, &usb->data); 347 if (IS_ERR(usb->dev)) { 348 err = dev_err_probe(&pdev->dev, PTR_ERR(usb->dev), 349 "failed to add HDRC device"); 350 goto phy_shutdown; 351 } 352 353 return 0; 354 355 phy_shutdown: 356 usb_phy_shutdown(usb->phy); 357 fail_power_off: 358 pm_runtime_put_sync_suspend(&pdev->dev); 359 pm_runtime_force_suspend(&pdev->dev); 360 361 return err; 362 } 363 364 static void tegra_usb_remove(struct platform_device *pdev) 365 { 366 struct tegra_usb *usb = platform_get_drvdata(pdev); 367 368 ci_hdrc_remove_device(usb->dev); 369 usb_phy_shutdown(usb->phy); 370 371 pm_runtime_put_sync_suspend(&pdev->dev); 372 pm_runtime_force_suspend(&pdev->dev); 373 } 374 375 static int tegra_usb_runtime_resume(struct device *dev) 376 { 377 struct tegra_usb *usb = dev_get_drvdata(dev); 378 int err; 379 380 err = clk_prepare_enable(usb->clk); 381 if (err < 0) { 382 dev_err(dev, "failed to enable clock: %d\n", err); 383 return err; 384 } 385 386 return 0; 387 } 388 389 static int tegra_usb_runtime_suspend(struct device *dev) 390 { 391 struct tegra_usb *usb = dev_get_drvdata(dev); 392 393 clk_disable_unprepare(usb->clk); 394 395 return 0; 396 } 397 398 static const struct dev_pm_ops tegra_usb_pm = { 399 RUNTIME_PM_OPS(tegra_usb_runtime_suspend, tegra_usb_runtime_resume, NULL) 400 }; 401 402 static struct platform_driver tegra_usb_driver = { 403 .driver = { 404 .name = "tegra-usb", 405 .of_match_table = tegra_usb_of_match, 406 .pm = pm_ptr(&tegra_usb_pm), 407 }, 408 .probe = tegra_usb_probe, 409 .remove_new = tegra_usb_remove, 410 }; 411 module_platform_driver(tegra_usb_driver); 412 413 MODULE_DESCRIPTION("NVIDIA Tegra USB driver"); 414 MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>"); 415 MODULE_LICENSE("GPL v2"); 416