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_device.h>
10 #include <linux/pm_runtime.h>
11 #include <linux/reset.h>
12
13 #include <linux/usb.h>
14 #include <linux/usb/chipidea.h>
15 #include <linux/usb/hcd.h>
16 #include <linux/usb/of.h>
17 #include <linux/usb/phy.h>
18
19 #include <soc/tegra/common.h>
20
21 #include "../host/ehci.h"
22
23 #include "ci.h"
24
25 struct tegra_usb {
26 struct ci_hdrc_platform_data data;
27 struct platform_device *dev;
28
29 const struct tegra_usb_soc_info *soc;
30 struct usb_phy *phy;
31 struct clk *clk;
32
33 bool needs_double_reset;
34 };
35
36 struct tegra_usb_soc_info {
37 unsigned long flags;
38 unsigned int txfifothresh;
39 enum usb_dr_mode dr_mode;
40 };
41
42 static const struct tegra_usb_soc_info tegra20_ehci_soc_info = {
43 .flags = CI_HDRC_REQUIRES_ALIGNED_DMA |
44 CI_HDRC_OVERRIDE_PHY_CONTROL |
45 CI_HDRC_SUPPORTS_RUNTIME_PM,
46 .dr_mode = USB_DR_MODE_HOST,
47 .txfifothresh = 10,
48 };
49
50 static const struct tegra_usb_soc_info tegra30_ehci_soc_info = {
51 .flags = CI_HDRC_REQUIRES_ALIGNED_DMA |
52 CI_HDRC_OVERRIDE_PHY_CONTROL |
53 CI_HDRC_SUPPORTS_RUNTIME_PM,
54 .dr_mode = USB_DR_MODE_HOST,
55 .txfifothresh = 16,
56 };
57
58 static const struct tegra_usb_soc_info tegra20_udc_soc_info = {
59 .flags = CI_HDRC_REQUIRES_ALIGNED_DMA |
60 CI_HDRC_OVERRIDE_PHY_CONTROL |
61 CI_HDRC_SUPPORTS_RUNTIME_PM,
62 .dr_mode = USB_DR_MODE_UNKNOWN,
63 .txfifothresh = 10,
64 };
65
66 static const struct tegra_usb_soc_info tegra30_udc_soc_info = {
67 .flags = CI_HDRC_REQUIRES_ALIGNED_DMA |
68 CI_HDRC_OVERRIDE_PHY_CONTROL |
69 CI_HDRC_SUPPORTS_RUNTIME_PM,
70 .dr_mode = USB_DR_MODE_UNKNOWN,
71 .txfifothresh = 16,
72 };
73
74 static const struct of_device_id tegra_usb_of_match[] = {
75 {
76 .compatible = "nvidia,tegra20-ehci",
77 .data = &tegra20_ehci_soc_info,
78 }, {
79 .compatible = "nvidia,tegra30-ehci",
80 .data = &tegra30_ehci_soc_info,
81 }, {
82 .compatible = "nvidia,tegra20-udc",
83 .data = &tegra20_udc_soc_info,
84 }, {
85 .compatible = "nvidia,tegra30-udc",
86 .data = &tegra30_udc_soc_info,
87 }, {
88 .compatible = "nvidia,tegra114-udc",
89 .data = &tegra30_udc_soc_info,
90 }, {
91 .compatible = "nvidia,tegra124-udc",
92 .data = &tegra30_udc_soc_info,
93 }, {
94 /* sentinel */
95 }
96 };
97 MODULE_DEVICE_TABLE(of, tegra_usb_of_match);
98
tegra_usb_reset_controller(struct device * dev)99 static int tegra_usb_reset_controller(struct device *dev)
100 {
101 struct reset_control *rst, *rst_utmi;
102 struct device_node *phy_np;
103 int err;
104
105 rst = devm_reset_control_get_shared(dev, "usb");
106 if (IS_ERR(rst)) {
107 dev_err(dev, "can't get ehci reset: %pe\n", rst);
108 return PTR_ERR(rst);
109 }
110
111 phy_np = of_parse_phandle(dev->of_node, "nvidia,phy", 0);
112 if (!phy_np)
113 return -ENOENT;
114
115 /*
116 * The 1st USB controller contains some UTMI pad registers that are
117 * global for all the controllers on the chip. Those registers are
118 * also cleared when reset is asserted to the 1st controller.
119 */
120 rst_utmi = of_reset_control_get_shared(phy_np, "utmi-pads");
121 if (IS_ERR(rst_utmi)) {
122 dev_warn(dev, "can't get utmi-pads reset from the PHY\n");
123 dev_warn(dev, "continuing, but please update your DT\n");
124 } else {
125 /*
126 * PHY driver performs UTMI-pads reset in a case of a
127 * non-legacy DT.
128 */
129 reset_control_put(rst_utmi);
130 }
131
132 of_node_put(phy_np);
133
134 /* reset control is shared, hence initialize it first */
135 err = reset_control_deassert(rst);
136 if (err)
137 return err;
138
139 err = reset_control_assert(rst);
140 if (err)
141 return err;
142
143 udelay(1);
144
145 err = reset_control_deassert(rst);
146 if (err)
147 return err;
148
149 return 0;
150 }
151
tegra_usb_notify_event(struct ci_hdrc * ci,unsigned int event)152 static int tegra_usb_notify_event(struct ci_hdrc *ci, unsigned int event)
153 {
154 struct tegra_usb *usb = dev_get_drvdata(ci->dev->parent);
155 struct ehci_hcd *ehci;
156
157 switch (event) {
158 case CI_HDRC_CONTROLLER_RESET_EVENT:
159 if (ci->hcd) {
160 ehci = hcd_to_ehci(ci->hcd);
161 ehci->has_tdi_phy_lpm = false;
162 ehci_writel(ehci, usb->soc->txfifothresh << 16,
163 &ehci->regs->txfill_tuning);
164 }
165 break;
166 }
167
168 return 0;
169 }
170
tegra_usb_internal_port_reset(struct ehci_hcd * ehci,u32 __iomem * portsc_reg,unsigned long * flags)171 static int tegra_usb_internal_port_reset(struct ehci_hcd *ehci,
172 u32 __iomem *portsc_reg,
173 unsigned long *flags)
174 {
175 u32 saved_usbintr, temp;
176 unsigned int i, tries;
177 int retval = 0;
178
179 saved_usbintr = ehci_readl(ehci, &ehci->regs->intr_enable);
180 /* disable USB interrupt */
181 ehci_writel(ehci, 0, &ehci->regs->intr_enable);
182 spin_unlock_irqrestore(&ehci->lock, *flags);
183
184 /*
185 * Here we have to do Port Reset at most twice for
186 * Port Enable bit to be set.
187 */
188 for (i = 0; i < 2; i++) {
189 temp = ehci_readl(ehci, portsc_reg);
190 temp |= PORT_RESET;
191 ehci_writel(ehci, temp, portsc_reg);
192 fsleep(10000);
193 temp &= ~PORT_RESET;
194 ehci_writel(ehci, temp, portsc_reg);
195 fsleep(1000);
196 tries = 100;
197 do {
198 fsleep(1000);
199 /*
200 * Up to this point, Port Enable bit is
201 * expected to be set after 2 ms waiting.
202 * USB1 usually takes extra 45 ms, for safety,
203 * we take 100 ms as timeout.
204 */
205 temp = ehci_readl(ehci, portsc_reg);
206 } while (!(temp & PORT_PE) && tries--);
207 if (temp & PORT_PE)
208 break;
209 }
210 if (i == 2)
211 retval = -ETIMEDOUT;
212
213 /*
214 * Clear Connect Status Change bit if it's set.
215 * We can't clear PORT_PEC. It will also cause PORT_PE to be cleared.
216 */
217 if (temp & PORT_CSC)
218 ehci_writel(ehci, PORT_CSC, portsc_reg);
219
220 /*
221 * Write to clear any interrupt status bits that might be set
222 * during port reset.
223 */
224 temp = ehci_readl(ehci, &ehci->regs->status);
225 ehci_writel(ehci, temp, &ehci->regs->status);
226
227 /* restore original interrupt-enable bits */
228 spin_lock_irqsave(&ehci->lock, *flags);
229 ehci_writel(ehci, saved_usbintr, &ehci->regs->intr_enable);
230
231 return retval;
232 }
233
tegra_ehci_hub_control(struct ci_hdrc * ci,u16 typeReq,u16 wValue,u16 wIndex,char * buf,u16 wLength,bool * done,unsigned long * flags)234 static int tegra_ehci_hub_control(struct ci_hdrc *ci, u16 typeReq, u16 wValue,
235 u16 wIndex, char *buf, u16 wLength,
236 bool *done, unsigned long *flags)
237 {
238 struct tegra_usb *usb = dev_get_drvdata(ci->dev->parent);
239 struct ehci_hcd *ehci = hcd_to_ehci(ci->hcd);
240 u32 __iomem *status_reg;
241 int retval = 0;
242
243 status_reg = &ehci->regs->port_status[(wIndex & 0xff) - 1];
244
245 switch (typeReq) {
246 case SetPortFeature:
247 if (wValue != USB_PORT_FEAT_RESET || !usb->needs_double_reset)
248 break;
249
250 /* for USB1 port we need to issue Port Reset twice internally */
251 retval = tegra_usb_internal_port_reset(ehci, status_reg, flags);
252 *done = true;
253 break;
254 }
255
256 return retval;
257 }
258
tegra_usb_enter_lpm(struct ci_hdrc * ci,bool enable)259 static void tegra_usb_enter_lpm(struct ci_hdrc *ci, bool enable)
260 {
261 /*
262 * Touching any register which belongs to AHB clock domain will
263 * hang CPU if USB controller is put into low power mode because
264 * AHB USB clock is gated on Tegra in the LPM.
265 *
266 * Tegra PHY has a separate register for checking the clock status
267 * and usb_phy_set_suspend() takes care of gating/ungating the clocks
268 * and restoring the PHY state on Tegra. Hence DEVLC/PORTSC registers
269 * shouldn't be touched directly by the CI driver.
270 */
271 usb_phy_set_suspend(ci->usb_phy, enable);
272 }
273
tegra_usb_probe(struct platform_device * pdev)274 static int tegra_usb_probe(struct platform_device *pdev)
275 {
276 const struct tegra_usb_soc_info *soc;
277 struct tegra_usb *usb;
278 int err;
279
280 usb = devm_kzalloc(&pdev->dev, sizeof(*usb), GFP_KERNEL);
281 if (!usb)
282 return -ENOMEM;
283
284 platform_set_drvdata(pdev, usb);
285
286 soc = of_device_get_match_data(&pdev->dev);
287 if (!soc) {
288 dev_err(&pdev->dev, "failed to match OF data\n");
289 return -EINVAL;
290 }
291
292 usb->phy = devm_usb_get_phy_by_phandle(&pdev->dev, "nvidia,phy", 0);
293 if (IS_ERR(usb->phy))
294 return dev_err_probe(&pdev->dev, PTR_ERR(usb->phy),
295 "failed to get PHY\n");
296
297 usb->clk = devm_clk_get(&pdev->dev, NULL);
298 if (IS_ERR(usb->clk)) {
299 err = PTR_ERR(usb->clk);
300 dev_err(&pdev->dev, "failed to get clock: %d\n", err);
301 return err;
302 }
303
304 err = devm_tegra_core_dev_init_opp_table_common(&pdev->dev);
305 if (err)
306 return err;
307
308 pm_runtime_enable(&pdev->dev);
309 err = pm_runtime_resume_and_get(&pdev->dev);
310 if (err)
311 return err;
312
313 if (device_property_present(&pdev->dev, "nvidia,needs-double-reset"))
314 usb->needs_double_reset = true;
315
316 err = tegra_usb_reset_controller(&pdev->dev);
317 if (err) {
318 dev_err(&pdev->dev, "failed to reset controller: %d\n", err);
319 goto fail_power_off;
320 }
321
322 /*
323 * USB controller registers shouldn't be touched before PHY is
324 * initialized, otherwise CPU will hang because clocks are gated.
325 * PHY driver controls gating of internal USB clocks on Tegra.
326 */
327 err = usb_phy_init(usb->phy);
328 if (err)
329 goto fail_power_off;
330
331 /* setup and register ChipIdea HDRC device */
332 usb->soc = soc;
333 usb->data.name = "tegra-usb";
334 usb->data.flags = soc->flags;
335 usb->data.usb_phy = usb->phy;
336 usb->data.dr_mode = soc->dr_mode;
337 usb->data.capoffset = DEF_CAPOFFSET;
338 usb->data.enter_lpm = tegra_usb_enter_lpm;
339 usb->data.hub_control = tegra_ehci_hub_control;
340 usb->data.notify_event = tegra_usb_notify_event;
341
342 /* Tegra PHY driver currently doesn't support LPM for ULPI */
343 if (of_usb_get_phy_mode(pdev->dev.of_node) == USBPHY_INTERFACE_MODE_ULPI)
344 usb->data.flags &= ~CI_HDRC_SUPPORTS_RUNTIME_PM;
345
346 usb->dev = ci_hdrc_add_device(&pdev->dev, pdev->resource,
347 pdev->num_resources, &usb->data);
348 if (IS_ERR(usb->dev)) {
349 err = PTR_ERR(usb->dev);
350 dev_err(&pdev->dev, "failed to add HDRC device: %d\n", err);
351 goto phy_shutdown;
352 }
353
354 return 0;
355
356 phy_shutdown:
357 usb_phy_shutdown(usb->phy);
358 fail_power_off:
359 pm_runtime_put_sync_suspend(&pdev->dev);
360 pm_runtime_force_suspend(&pdev->dev);
361
362 return err;
363 }
364
tegra_usb_remove(struct platform_device * pdev)365 static int tegra_usb_remove(struct platform_device *pdev)
366 {
367 struct tegra_usb *usb = platform_get_drvdata(pdev);
368
369 ci_hdrc_remove_device(usb->dev);
370 usb_phy_shutdown(usb->phy);
371
372 pm_runtime_put_sync_suspend(&pdev->dev);
373 pm_runtime_force_suspend(&pdev->dev);
374
375 return 0;
376 }
377
tegra_usb_runtime_resume(struct device * dev)378 static int __maybe_unused tegra_usb_runtime_resume(struct device *dev)
379 {
380 struct tegra_usb *usb = dev_get_drvdata(dev);
381 int err;
382
383 err = clk_prepare_enable(usb->clk);
384 if (err < 0) {
385 dev_err(dev, "failed to enable clock: %d\n", err);
386 return err;
387 }
388
389 return 0;
390 }
391
tegra_usb_runtime_suspend(struct device * dev)392 static int __maybe_unused tegra_usb_runtime_suspend(struct device *dev)
393 {
394 struct tegra_usb *usb = dev_get_drvdata(dev);
395
396 clk_disable_unprepare(usb->clk);
397
398 return 0;
399 }
400
401 static const struct dev_pm_ops tegra_usb_pm = {
402 SET_RUNTIME_PM_OPS(tegra_usb_runtime_suspend, tegra_usb_runtime_resume,
403 NULL)
404 };
405
406 static struct platform_driver tegra_usb_driver = {
407 .driver = {
408 .name = "tegra-usb",
409 .of_match_table = tegra_usb_of_match,
410 .pm = &tegra_usb_pm,
411 },
412 .probe = tegra_usb_probe,
413 .remove = tegra_usb_remove,
414 };
415 module_platform_driver(tegra_usb_driver);
416
417 MODULE_DESCRIPTION("NVIDIA Tegra USB driver");
418 MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
419 MODULE_LICENSE("GPL v2");
420