1 /*
2  * phy-brcm-usb.c - Broadcom USB Phy Driver
3  *
4  * Copyright (C) 2015-2017 Broadcom
5  *
6  * This software is licensed under the terms of the GNU General Public
7  * License version 2, as published by the Free Software Foundation, and
8  * may be copied, distributed, and modified under those terms.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15 
16 #include <linux/clk.h>
17 #include <linux/delay.h>
18 #include <linux/err.h>
19 #include <linux/io.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/phy/phy.h>
23 #include <linux/platform_device.h>
24 #include <linux/interrupt.h>
25 #include <linux/soc/brcmstb/brcmstb.h>
26 #include <dt-bindings/phy/phy.h>
27 
28 #include "phy-brcm-usb-init.h"
29 
30 static DEFINE_MUTEX(sysfs_lock);
31 
32 enum brcm_usb_phy_id {
33 	BRCM_USB_PHY_2_0 = 0,
34 	BRCM_USB_PHY_3_0,
35 	BRCM_USB_PHY_ID_MAX
36 };
37 
38 struct value_to_name_map {
39 	int value;
40 	const char *name;
41 };
42 
43 static struct value_to_name_map brcm_dr_mode_to_name[] = {
44 	{ USB_CTLR_MODE_HOST, "host" },
45 	{ USB_CTLR_MODE_DEVICE, "peripheral" },
46 	{ USB_CTLR_MODE_DRD, "drd" },
47 	{ USB_CTLR_MODE_TYPEC_PD, "typec-pd" }
48 };
49 
50 static struct value_to_name_map brcm_dual_mode_to_name[] = {
51 	{ 0, "host" },
52 	{ 1, "device" },
53 	{ 2, "auto" },
54 };
55 
56 struct brcm_usb_phy {
57 	struct phy *phy;
58 	unsigned int id;
59 	bool inited;
60 };
61 
62 struct brcm_usb_phy_data {
63 	struct  brcm_usb_init_params ini;
64 	bool			has_eohci;
65 	bool			has_xhci;
66 	struct clk		*usb_20_clk;
67 	struct clk		*usb_30_clk;
68 	struct mutex		mutex;	/* serialize phy init */
69 	int			init_count;
70 	struct brcm_usb_phy	phys[BRCM_USB_PHY_ID_MAX];
71 };
72 
73 static int brcm_usb_phy_init(struct phy *gphy)
74 {
75 	struct brcm_usb_phy *phy = phy_get_drvdata(gphy);
76 	struct brcm_usb_phy_data *priv =
77 		container_of(phy, struct brcm_usb_phy_data, phys[phy->id]);
78 
79 	/*
80 	 * Use a lock to make sure a second caller waits until
81 	 * the base phy is inited before using it.
82 	 */
83 	mutex_lock(&priv->mutex);
84 	if (priv->init_count++ == 0) {
85 		clk_enable(priv->usb_20_clk);
86 		clk_enable(priv->usb_30_clk);
87 		brcm_usb_init_common(&priv->ini);
88 	}
89 	mutex_unlock(&priv->mutex);
90 	if (phy->id == BRCM_USB_PHY_2_0)
91 		brcm_usb_init_eohci(&priv->ini);
92 	else if (phy->id == BRCM_USB_PHY_3_0)
93 		brcm_usb_init_xhci(&priv->ini);
94 	phy->inited = true;
95 	dev_dbg(&gphy->dev, "INIT, id: %d, total: %d\n", phy->id,
96 		priv->init_count);
97 
98 	return 0;
99 }
100 
101 static int brcm_usb_phy_exit(struct phy *gphy)
102 {
103 	struct brcm_usb_phy *phy = phy_get_drvdata(gphy);
104 	struct brcm_usb_phy_data *priv =
105 		container_of(phy, struct brcm_usb_phy_data, phys[phy->id]);
106 
107 	dev_dbg(&gphy->dev, "EXIT\n");
108 	if (phy->id == BRCM_USB_PHY_2_0)
109 		brcm_usb_uninit_eohci(&priv->ini);
110 	if (phy->id == BRCM_USB_PHY_3_0)
111 		brcm_usb_uninit_xhci(&priv->ini);
112 
113 	/* If both xhci and eohci are gone, reset everything else */
114 	mutex_lock(&priv->mutex);
115 	if (--priv->init_count == 0) {
116 		brcm_usb_uninit_common(&priv->ini);
117 		clk_disable(priv->usb_20_clk);
118 		clk_disable(priv->usb_30_clk);
119 	}
120 	mutex_unlock(&priv->mutex);
121 	phy->inited = false;
122 	return 0;
123 }
124 
125 static struct phy_ops brcm_usb_phy_ops = {
126 	.init		= brcm_usb_phy_init,
127 	.exit		= brcm_usb_phy_exit,
128 	.owner		= THIS_MODULE,
129 };
130 
131 static struct phy *brcm_usb_phy_xlate(struct device *dev,
132 				      struct of_phandle_args *args)
133 {
134 	struct brcm_usb_phy_data *data = dev_get_drvdata(dev);
135 
136 	/*
137 	 * values 0 and 1 are for backward compatibility with
138 	 * device tree nodes from older bootloaders.
139 	 */
140 	switch (args->args[0]) {
141 	case 0:
142 	case PHY_TYPE_USB2:
143 		if (data->phys[BRCM_USB_PHY_2_0].phy)
144 			return data->phys[BRCM_USB_PHY_2_0].phy;
145 		dev_warn(dev, "Error, 2.0 Phy not found\n");
146 		break;
147 	case 1:
148 	case PHY_TYPE_USB3:
149 		if (data->phys[BRCM_USB_PHY_3_0].phy)
150 			return data->phys[BRCM_USB_PHY_3_0].phy;
151 		dev_warn(dev, "Error, 3.0 Phy not found\n");
152 		break;
153 	}
154 	return ERR_PTR(-ENODEV);
155 }
156 
157 static int name_to_value(struct value_to_name_map *table, int count,
158 			 const char *name, int *value)
159 {
160 	int x;
161 
162 	*value = 0;
163 	for (x = 0; x < count; x++) {
164 		if (sysfs_streq(name, table[x].name)) {
165 			*value = x;
166 			return 0;
167 		}
168 	}
169 	return -EINVAL;
170 }
171 
172 static const char *value_to_name(struct value_to_name_map *table, int count,
173 				 int value)
174 {
175 	if (value >= count)
176 		return "unknown";
177 	return table[value].name;
178 }
179 
180 static ssize_t dr_mode_show(struct device *dev,
181 			    struct device_attribute *attr,
182 			    char *buf)
183 {
184 	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
185 
186 	return sprintf(buf, "%s\n",
187 		value_to_name(&brcm_dr_mode_to_name[0],
188 			      ARRAY_SIZE(brcm_dr_mode_to_name),
189 			      priv->ini.mode));
190 }
191 static DEVICE_ATTR_RO(dr_mode);
192 
193 static ssize_t dual_select_store(struct device *dev,
194 				 struct device_attribute *attr,
195 				 const char *buf, size_t len)
196 {
197 	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
198 	int value;
199 	int res;
200 
201 	mutex_lock(&sysfs_lock);
202 	res = name_to_value(&brcm_dual_mode_to_name[0],
203 			    ARRAY_SIZE(brcm_dual_mode_to_name), buf, &value);
204 	if (!res) {
205 		brcm_usb_init_set_dual_select(&priv->ini, value);
206 		res = len;
207 	}
208 	mutex_unlock(&sysfs_lock);
209 	return res;
210 }
211 
212 static ssize_t dual_select_show(struct device *dev,
213 				struct device_attribute *attr,
214 				char *buf)
215 {
216 	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
217 	int value;
218 
219 	mutex_lock(&sysfs_lock);
220 	value = brcm_usb_init_get_dual_select(&priv->ini);
221 	mutex_unlock(&sysfs_lock);
222 	return sprintf(buf, "%s\n",
223 		value_to_name(&brcm_dual_mode_to_name[0],
224 			      ARRAY_SIZE(brcm_dual_mode_to_name),
225 			      value));
226 }
227 static DEVICE_ATTR_RW(dual_select);
228 
229 static struct attribute *brcm_usb_phy_attrs[] = {
230 	&dev_attr_dr_mode.attr,
231 	&dev_attr_dual_select.attr,
232 	NULL
233 };
234 
235 static const struct attribute_group brcm_usb_phy_group = {
236 	.attrs = brcm_usb_phy_attrs,
237 };
238 
239 static int brcm_usb_phy_dvr_init(struct device *dev,
240 				 struct brcm_usb_phy_data *priv,
241 				 struct device_node *dn)
242 {
243 	struct phy *gphy;
244 	int err;
245 
246 	priv->usb_20_clk = of_clk_get_by_name(dn, "sw_usb");
247 	if (IS_ERR(priv->usb_20_clk)) {
248 		dev_info(dev, "Clock not found in Device Tree\n");
249 		priv->usb_20_clk = NULL;
250 	}
251 	err = clk_prepare_enable(priv->usb_20_clk);
252 	if (err)
253 		return err;
254 
255 	if (priv->has_eohci) {
256 		gphy = devm_phy_create(dev, NULL, &brcm_usb_phy_ops);
257 		if (IS_ERR(gphy)) {
258 			dev_err(dev, "failed to create EHCI/OHCI PHY\n");
259 			return PTR_ERR(gphy);
260 		}
261 		priv->phys[BRCM_USB_PHY_2_0].phy = gphy;
262 		priv->phys[BRCM_USB_PHY_2_0].id = BRCM_USB_PHY_2_0;
263 		phy_set_drvdata(gphy, &priv->phys[BRCM_USB_PHY_2_0]);
264 	}
265 
266 	if (priv->has_xhci) {
267 		gphy = devm_phy_create(dev, NULL, &brcm_usb_phy_ops);
268 		if (IS_ERR(gphy)) {
269 			dev_err(dev, "failed to create XHCI PHY\n");
270 			return PTR_ERR(gphy);
271 		}
272 		priv->phys[BRCM_USB_PHY_3_0].phy = gphy;
273 		priv->phys[BRCM_USB_PHY_3_0].id = BRCM_USB_PHY_3_0;
274 		phy_set_drvdata(gphy, &priv->phys[BRCM_USB_PHY_3_0]);
275 
276 		priv->usb_30_clk = of_clk_get_by_name(dn, "sw_usb3");
277 		if (IS_ERR(priv->usb_30_clk)) {
278 			dev_info(dev,
279 				 "USB3.0 clock not found in Device Tree\n");
280 			priv->usb_30_clk = NULL;
281 		}
282 		err = clk_prepare_enable(priv->usb_30_clk);
283 		if (err)
284 			return err;
285 	}
286 	return 0;
287 }
288 
289 static int brcm_usb_phy_probe(struct platform_device *pdev)
290 {
291 	struct resource *res;
292 	struct device *dev = &pdev->dev;
293 	struct brcm_usb_phy_data *priv;
294 	struct phy_provider *phy_provider;
295 	struct device_node *dn = pdev->dev.of_node;
296 	int err;
297 	const char *mode;
298 
299 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
300 	if (!priv)
301 		return -ENOMEM;
302 	platform_set_drvdata(pdev, priv);
303 
304 	priv->ini.family_id = brcmstb_get_family_id();
305 	priv->ini.product_id = brcmstb_get_product_id();
306 	brcm_usb_set_family_map(&priv->ini);
307 	dev_dbg(dev, "Best mapping table is for %s\n",
308 		priv->ini.family_name);
309 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
310 	if (!res) {
311 		dev_err(dev, "can't get USB_CTRL base address\n");
312 		return -EINVAL;
313 	}
314 	priv->ini.ctrl_regs = devm_ioremap_resource(dev, res);
315 	if (IS_ERR(priv->ini.ctrl_regs)) {
316 		dev_err(dev, "can't map CTRL register space\n");
317 		return -EINVAL;
318 	}
319 
320 	/* The XHCI EC registers are optional */
321 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
322 	if (res) {
323 		priv->ini.xhci_ec_regs =
324 			devm_ioremap_resource(dev, res);
325 		if (IS_ERR(priv->ini.xhci_ec_regs)) {
326 			dev_err(dev, "can't map XHCI EC register space\n");
327 			return -EINVAL;
328 		}
329 	}
330 
331 	of_property_read_u32(dn, "brcm,ipp", &priv->ini.ipp);
332 	of_property_read_u32(dn, "brcm,ioc", &priv->ini.ioc);
333 
334 	priv->ini.mode = USB_CTLR_MODE_HOST;
335 	err = of_property_read_string(dn, "dr_mode", &mode);
336 	if (err == 0) {
337 		name_to_value(&brcm_dr_mode_to_name[0],
338 			      ARRAY_SIZE(brcm_dr_mode_to_name),
339 			mode, &priv->ini.mode);
340 	}
341 	if (of_property_read_bool(dn, "brcm,has-xhci"))
342 		priv->has_xhci = true;
343 	if (of_property_read_bool(dn, "brcm,has-eohci"))
344 		priv->has_eohci = true;
345 
346 	err = brcm_usb_phy_dvr_init(dev, priv, dn);
347 	if (err)
348 		return err;
349 
350 	mutex_init(&priv->mutex);
351 
352 	/* make sure invert settings are correct */
353 	brcm_usb_init_ipp(&priv->ini);
354 
355 	/*
356 	 * Create sysfs entries for mode.
357 	 * Remove "dual_select" attribute if not in dual mode
358 	 */
359 	if (priv->ini.mode != USB_CTLR_MODE_DRD)
360 		brcm_usb_phy_attrs[1] = NULL;
361 	err = sysfs_create_group(&dev->kobj, &brcm_usb_phy_group);
362 	if (err)
363 		dev_warn(dev, "Error creating sysfs attributes\n");
364 
365 	/* start with everything off */
366 	if (priv->has_xhci)
367 		brcm_usb_uninit_xhci(&priv->ini);
368 	if (priv->has_eohci)
369 		brcm_usb_uninit_eohci(&priv->ini);
370 	brcm_usb_uninit_common(&priv->ini);
371 	clk_disable(priv->usb_20_clk);
372 	clk_disable(priv->usb_30_clk);
373 
374 	phy_provider = devm_of_phy_provider_register(dev, brcm_usb_phy_xlate);
375 
376 	return PTR_ERR_OR_ZERO(phy_provider);
377 }
378 
379 #ifdef CONFIG_PM_SLEEP
380 static int brcm_usb_phy_suspend(struct device *dev)
381 {
382 	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
383 
384 	if (priv->init_count) {
385 		clk_disable(priv->usb_20_clk);
386 		clk_disable(priv->usb_30_clk);
387 	}
388 	return 0;
389 }
390 
391 static int brcm_usb_phy_resume(struct device *dev)
392 {
393 	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
394 
395 	clk_enable(priv->usb_20_clk);
396 	clk_enable(priv->usb_30_clk);
397 	brcm_usb_init_ipp(&priv->ini);
398 
399 	/*
400 	 * Initialize anything that was previously initialized.
401 	 * Uninitialize anything that wasn't previously initialized.
402 	 */
403 	if (priv->init_count) {
404 		brcm_usb_init_common(&priv->ini);
405 		if (priv->phys[BRCM_USB_PHY_2_0].inited) {
406 			brcm_usb_init_eohci(&priv->ini);
407 		} else if (priv->has_eohci) {
408 			brcm_usb_uninit_eohci(&priv->ini);
409 			clk_disable(priv->usb_20_clk);
410 		}
411 		if (priv->phys[BRCM_USB_PHY_3_0].inited) {
412 			brcm_usb_init_xhci(&priv->ini);
413 		} else if (priv->has_xhci) {
414 			brcm_usb_uninit_xhci(&priv->ini);
415 			clk_disable(priv->usb_30_clk);
416 		}
417 	} else {
418 		if (priv->has_xhci)
419 			brcm_usb_uninit_xhci(&priv->ini);
420 		if (priv->has_eohci)
421 			brcm_usb_uninit_eohci(&priv->ini);
422 		brcm_usb_uninit_common(&priv->ini);
423 		clk_disable(priv->usb_20_clk);
424 		clk_disable(priv->usb_30_clk);
425 	}
426 
427 	return 0;
428 }
429 #endif /* CONFIG_PM_SLEEP */
430 
431 static const struct dev_pm_ops brcm_usb_phy_pm_ops = {
432 	SET_LATE_SYSTEM_SLEEP_PM_OPS(brcm_usb_phy_suspend, brcm_usb_phy_resume)
433 };
434 
435 static const struct of_device_id brcm_usb_dt_ids[] = {
436 	{ .compatible = "brcm,brcmstb-usb-phy" },
437 	{ /* sentinel */ }
438 };
439 
440 MODULE_DEVICE_TABLE(of, brcm_usb_dt_ids);
441 
442 static struct platform_driver brcm_usb_driver = {
443 	.probe		= brcm_usb_phy_probe,
444 	.driver		= {
445 		.name	= "brcmstb-usb-phy",
446 		.owner	= THIS_MODULE,
447 		.pm = &brcm_usb_phy_pm_ops,
448 		.of_match_table = brcm_usb_dt_ids,
449 	},
450 };
451 
452 module_platform_driver(brcm_usb_driver);
453 
454 MODULE_ALIAS("platform:brcmstb-usb-phy");
455 MODULE_AUTHOR("Al Cooper <acooper@broadcom.com>");
456 MODULE_DESCRIPTION("BRCM USB PHY driver");
457 MODULE_LICENSE("GPL v2");
458