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
 30static DEFINE_MUTEX(sysfs_lock);
 31
 32enum 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
 38struct value_to_name_map {
 39	int value;
 40	const char *name;
 41};
 42
 43static 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
 50static struct value_to_name_map brcm_dual_mode_to_name[] = {
 51	{ 0, "host" },
 52	{ 1, "device" },
 53	{ 2, "auto" },
 54};
 55
 56struct brcm_usb_phy {
 57	struct phy *phy;
 58	unsigned int id;
 59	bool inited;
 60};
 61
 62struct 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
 73static 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
101static 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
125static 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
131static 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
157static 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
172static 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
180static 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}
191static DEVICE_ATTR_RO(dr_mode);
192
193static 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
212static 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}
227static DEVICE_ATTR_RW(dual_select);
228
229static struct attribute *brcm_usb_phy_attrs[] = {
230	&dev_attr_dr_mode.attr,
231	&dev_attr_dual_select.attr,
232	NULL
233};
234
235static const struct attribute_group brcm_usb_phy_group = {
236	.attrs = brcm_usb_phy_attrs,
237};
238
239static 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
289static 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	if (IS_ERR(phy_provider))
376		return PTR_ERR(phy_provider);
377
378	return 0;
379}
380
381#ifdef CONFIG_PM_SLEEP
382static int brcm_usb_phy_suspend(struct device *dev)
383{
384	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
385
386	if (priv->init_count) {
387		clk_disable(priv->usb_20_clk);
388		clk_disable(priv->usb_30_clk);
389	}
390	return 0;
391}
392
393static int brcm_usb_phy_resume(struct device *dev)
394{
395	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
396
397	clk_enable(priv->usb_20_clk);
398	clk_enable(priv->usb_30_clk);
399	brcm_usb_init_ipp(&priv->ini);
400
401	/*
402	 * Initialize anything that was previously initialized.
403	 * Uninitialize anything that wasn't previously initialized.
404	 */
405	if (priv->init_count) {
406		brcm_usb_init_common(&priv->ini);
407		if (priv->phys[BRCM_USB_PHY_2_0].inited) {
408			brcm_usb_init_eohci(&priv->ini);
409		} else if (priv->has_eohci) {
410			brcm_usb_uninit_eohci(&priv->ini);
411			clk_disable(priv->usb_20_clk);
412		}
413		if (priv->phys[BRCM_USB_PHY_3_0].inited) {
414			brcm_usb_init_xhci(&priv->ini);
415		} else if (priv->has_xhci) {
416			brcm_usb_uninit_xhci(&priv->ini);
417			clk_disable(priv->usb_30_clk);
418		}
419	} else {
420		if (priv->has_xhci)
421			brcm_usb_uninit_xhci(&priv->ini);
422		if (priv->has_eohci)
423			brcm_usb_uninit_eohci(&priv->ini);
424		brcm_usb_uninit_common(&priv->ini);
425		clk_disable(priv->usb_20_clk);
426		clk_disable(priv->usb_30_clk);
427	}
428
429	return 0;
430}
431#endif /* CONFIG_PM_SLEEP */
432
433static const struct dev_pm_ops brcm_usb_phy_pm_ops = {
434	SET_LATE_SYSTEM_SLEEP_PM_OPS(brcm_usb_phy_suspend, brcm_usb_phy_resume)
435};
436
437static const struct of_device_id brcm_usb_dt_ids[] = {
438	{ .compatible = "brcm,brcmstb-usb-phy" },
439	{ /* sentinel */ }
440};
441
442MODULE_DEVICE_TABLE(of, brcm_usb_dt_ids);
443
444static struct platform_driver brcm_usb_driver = {
445	.probe		= brcm_usb_phy_probe,
446	.driver		= {
447		.name	= "brcmstb-usb-phy",
448		.owner	= THIS_MODULE,
449		.pm = &brcm_usb_phy_pm_ops,
450		.of_match_table = brcm_usb_dt_ids,
451	},
452};
453
454module_platform_driver(brcm_usb_driver);
455
456MODULE_ALIAS("platform:brcmstb-usb-phy");
457MODULE_AUTHOR("Al Cooper <acooper@broadcom.com>");
458MODULE_DESCRIPTION("BRCM USB PHY driver");
459MODULE_LICENSE("GPL v2");