1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2009-2018, Linux Foundation. All rights reserved.
4 * Copyright (c) 2018-2020, Linaro Limited
5 */
6
7#include <linux/clk.h>
8#include <linux/delay.h>
9#include <linux/io.h>
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/of.h>
13#include <linux/of_graph.h>
14#include <linux/phy/phy.h>
15#include <linux/platform_device.h>
16#include <linux/regulator/consumer.h>
17#include <linux/reset.h>
18#include <linux/slab.h>
19
20/* PHY register and bit definitions */
21#define PHY_CTRL_COMMON0		0x078
22#define SIDDQ				BIT(2)
23#define PHY_IRQ_CMD			0x0d0
24#define PHY_INTR_MASK0			0x0d4
25#define PHY_INTR_CLEAR0			0x0dc
26#define DPDM_MASK			0x1e
27#define DP_1_0				BIT(4)
28#define DP_0_1				BIT(3)
29#define DM_1_0				BIT(2)
30#define DM_0_1				BIT(1)
31
32enum hsphy_voltage {
33	VOL_NONE,
34	VOL_MIN,
35	VOL_MAX,
36	VOL_NUM,
37};
38
39enum hsphy_vreg {
40	VDD,
41	VDDA_1P8,
42	VDDA_3P3,
43	VREG_NUM,
44};
45
46struct hsphy_init_seq {
47	int offset;
48	int val;
49	int delay;
50};
51
52struct hsphy_data {
53	const struct hsphy_init_seq *init_seq;
54	unsigned int init_seq_num;
55};
56
57struct hsphy_priv {
58	void __iomem *base;
59	struct clk_bulk_data *clks;
60	int num_clks;
61	struct reset_control *phy_reset;
62	struct reset_control *por_reset;
63	struct regulator_bulk_data vregs[VREG_NUM];
64	const struct hsphy_data *data;
65	enum phy_mode mode;
66};
67
68static int qcom_snps_hsphy_set_mode(struct phy *phy, enum phy_mode mode,
69				    int submode)
70{
71	struct hsphy_priv *priv = phy_get_drvdata(phy);
72
73	priv->mode = PHY_MODE_INVALID;
74
75	if (mode > 0)
76		priv->mode = mode;
77
78	return 0;
79}
80
81static void qcom_snps_hsphy_enable_hv_interrupts(struct hsphy_priv *priv)
82{
83	u32 val;
84
85	/* Clear any existing interrupts before enabling the interrupts */
86	val = readb(priv->base + PHY_INTR_CLEAR0);
87	val |= DPDM_MASK;
88	writeb(val, priv->base + PHY_INTR_CLEAR0);
89
90	writeb(0x0, priv->base + PHY_IRQ_CMD);
91	usleep_range(200, 220);
92	writeb(0x1, priv->base + PHY_IRQ_CMD);
93
94	/* Make sure the interrupts are cleared */
95	usleep_range(200, 220);
96
97	val = readb(priv->base + PHY_INTR_MASK0);
98	switch (priv->mode) {
99	case PHY_MODE_USB_HOST_HS:
100	case PHY_MODE_USB_HOST_FS:
101	case PHY_MODE_USB_DEVICE_HS:
102	case PHY_MODE_USB_DEVICE_FS:
103		val |= DP_1_0 | DM_0_1;
104		break;
105	case PHY_MODE_USB_HOST_LS:
106	case PHY_MODE_USB_DEVICE_LS:
107		val |= DP_0_1 | DM_1_0;
108		break;
109	default:
110		/* No device connected */
111		val |= DP_0_1 | DM_0_1;
112		break;
113	}
114	writeb(val, priv->base + PHY_INTR_MASK0);
115}
116
117static void qcom_snps_hsphy_disable_hv_interrupts(struct hsphy_priv *priv)
118{
119	u32 val;
120
121	val = readb(priv->base + PHY_INTR_MASK0);
122	val &= ~DPDM_MASK;
123	writeb(val, priv->base + PHY_INTR_MASK0);
124
125	/* Clear any pending interrupts */
126	val = readb(priv->base + PHY_INTR_CLEAR0);
127	val |= DPDM_MASK;
128	writeb(val, priv->base + PHY_INTR_CLEAR0);
129
130	writeb(0x0, priv->base + PHY_IRQ_CMD);
131	usleep_range(200, 220);
132
133	writeb(0x1, priv->base + PHY_IRQ_CMD);
134	usleep_range(200, 220);
135}
136
137static void qcom_snps_hsphy_enter_retention(struct hsphy_priv *priv)
138{
139	u32 val;
140
141	val = readb(priv->base + PHY_CTRL_COMMON0);
142	val |= SIDDQ;
143	writeb(val, priv->base + PHY_CTRL_COMMON0);
144}
145
146static void qcom_snps_hsphy_exit_retention(struct hsphy_priv *priv)
147{
148	u32 val;
149
150	val = readb(priv->base + PHY_CTRL_COMMON0);
151	val &= ~SIDDQ;
152	writeb(val, priv->base + PHY_CTRL_COMMON0);
153}
154
155static int qcom_snps_hsphy_power_on(struct phy *phy)
156{
157	struct hsphy_priv *priv = phy_get_drvdata(phy);
158	int ret;
159
160	ret = regulator_bulk_enable(VREG_NUM, priv->vregs);
161	if (ret)
162		return ret;
163
164	qcom_snps_hsphy_disable_hv_interrupts(priv);
165	qcom_snps_hsphy_exit_retention(priv);
166
167	return 0;
168}
169
170static int qcom_snps_hsphy_power_off(struct phy *phy)
171{
172	struct hsphy_priv *priv = phy_get_drvdata(phy);
173
174	qcom_snps_hsphy_enter_retention(priv);
175	qcom_snps_hsphy_enable_hv_interrupts(priv);
176	regulator_bulk_disable(VREG_NUM, priv->vregs);
177
178	return 0;
179}
180
181static int qcom_snps_hsphy_reset(struct hsphy_priv *priv)
182{
183	int ret;
184
185	ret = reset_control_assert(priv->phy_reset);
186	if (ret)
187		return ret;
188
189	usleep_range(10, 15);
190
191	ret = reset_control_deassert(priv->phy_reset);
192	if (ret)
193		return ret;
194
195	usleep_range(80, 100);
196
197	return 0;
198}
199
200static void qcom_snps_hsphy_init_sequence(struct hsphy_priv *priv)
201{
202	const struct hsphy_data *data = priv->data;
203	const struct hsphy_init_seq *seq;
204	int i;
205
206	/* Device match data is optional. */
207	if (!data)
208		return;
209
210	seq = data->init_seq;
211
212	for (i = 0; i < data->init_seq_num; i++, seq++) {
213		writeb(seq->val, priv->base + seq->offset);
214		if (seq->delay)
215			usleep_range(seq->delay, seq->delay + 10);
216	}
217}
218
219static int qcom_snps_hsphy_por_reset(struct hsphy_priv *priv)
220{
221	int ret;
222
223	ret = reset_control_assert(priv->por_reset);
224	if (ret)
225		return ret;
226
227	/*
228	 * The Femto PHY is POR reset in the following scenarios.
229	 *
230	 * 1. After overriding the parameter registers.
231	 * 2. Low power mode exit from PHY retention.
232	 *
233	 * Ensure that SIDDQ is cleared before bringing the PHY
234	 * out of reset.
235	 */
236	qcom_snps_hsphy_exit_retention(priv);
237
238	/*
239	 * As per databook, 10 usec delay is required between
240	 * PHY POR assert and de-assert.
241	 */
242	usleep_range(10, 20);
243	ret = reset_control_deassert(priv->por_reset);
244	if (ret)
245		return ret;
246
247	/*
248	 * As per databook, it takes 75 usec for PHY to stabilize
249	 * after the reset.
250	 */
251	usleep_range(80, 100);
252
253	return 0;
254}
255
256static int qcom_snps_hsphy_init(struct phy *phy)
257{
258	struct hsphy_priv *priv = phy_get_drvdata(phy);
259	int ret;
260
261	ret = clk_bulk_prepare_enable(priv->num_clks, priv->clks);
262	if (ret)
263		return ret;
264
265	ret = qcom_snps_hsphy_reset(priv);
266	if (ret)
267		goto disable_clocks;
268
269	qcom_snps_hsphy_init_sequence(priv);
270
271	ret = qcom_snps_hsphy_por_reset(priv);
272	if (ret)
273		goto disable_clocks;
274
275	return 0;
276
277disable_clocks:
278	clk_bulk_disable_unprepare(priv->num_clks, priv->clks);
279	return ret;
280}
281
282static int qcom_snps_hsphy_exit(struct phy *phy)
283{
284	struct hsphy_priv *priv = phy_get_drvdata(phy);
285
286	clk_bulk_disable_unprepare(priv->num_clks, priv->clks);
287
288	return 0;
289}
290
291static const struct phy_ops qcom_snps_hsphy_ops = {
292	.init = qcom_snps_hsphy_init,
293	.exit = qcom_snps_hsphy_exit,
294	.power_on = qcom_snps_hsphy_power_on,
295	.power_off = qcom_snps_hsphy_power_off,
296	.set_mode = qcom_snps_hsphy_set_mode,
297	.owner = THIS_MODULE,
298};
299
300static const char * const qcom_snps_hsphy_clks[] = {
301	"ref",
302	"ahb",
303	"sleep",
304};
305
306static int qcom_snps_hsphy_probe(struct platform_device *pdev)
307{
308	struct device *dev = &pdev->dev;
309	struct phy_provider *provider;
310	struct hsphy_priv *priv;
311	struct phy *phy;
312	int ret;
313	int i;
314
315	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
316	if (!priv)
317		return -ENOMEM;
318
319	priv->base = devm_platform_ioremap_resource(pdev, 0);
320	if (IS_ERR(priv->base))
321		return PTR_ERR(priv->base);
322
323	priv->num_clks = ARRAY_SIZE(qcom_snps_hsphy_clks);
324	priv->clks = devm_kcalloc(dev, priv->num_clks, sizeof(*priv->clks),
325				  GFP_KERNEL);
326	if (!priv->clks)
327		return -ENOMEM;
328
329	for (i = 0; i < priv->num_clks; i++)
330		priv->clks[i].id = qcom_snps_hsphy_clks[i];
331
332	ret = devm_clk_bulk_get(dev, priv->num_clks, priv->clks);
333	if (ret)
334		return ret;
335
336	priv->phy_reset = devm_reset_control_get_exclusive(dev, "phy");
337	if (IS_ERR(priv->phy_reset))
338		return PTR_ERR(priv->phy_reset);
339
340	priv->por_reset = devm_reset_control_get_exclusive(dev, "por");
341	if (IS_ERR(priv->por_reset))
342		return PTR_ERR(priv->por_reset);
343
344	priv->vregs[VDD].supply = "vdd";
345	priv->vregs[VDDA_1P8].supply = "vdda1p8";
346	priv->vregs[VDDA_3P3].supply = "vdda3p3";
347
348	ret = devm_regulator_bulk_get(dev, VREG_NUM, priv->vregs);
349	if (ret)
350		return ret;
351
352	/* Get device match data */
353	priv->data = device_get_match_data(dev);
354
355	phy = devm_phy_create(dev, dev->of_node, &qcom_snps_hsphy_ops);
356	if (IS_ERR(phy))
357		return PTR_ERR(phy);
358
359	phy_set_drvdata(phy, priv);
360
361	provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
362	if (IS_ERR(provider))
363		return PTR_ERR(provider);
364
365	ret = regulator_set_load(priv->vregs[VDDA_1P8].consumer, 19000);
366	if (ret < 0)
367		return ret;
368
369	ret = regulator_set_load(priv->vregs[VDDA_3P3].consumer, 16000);
370	if (ret < 0)
371		goto unset_1p8_load;
372
373	return 0;
374
375unset_1p8_load:
376	regulator_set_load(priv->vregs[VDDA_1P8].consumer, 0);
377
378	return ret;
379}
380
381/*
382 * The macro is used to define an initialization sequence.  Each tuple
383 * is meant to program 'value' into phy register at 'offset' with 'delay'
384 * in us followed.
385 */
386#define HSPHY_INIT_CFG(o, v, d)	{ .offset = o, .val = v, .delay = d, }
387
388static const struct hsphy_init_seq init_seq_femtophy[] = {
389	HSPHY_INIT_CFG(0xc0, 0x01, 0),
390	HSPHY_INIT_CFG(0xe8, 0x0d, 0),
391	HSPHY_INIT_CFG(0x74, 0x12, 0),
392	HSPHY_INIT_CFG(0x98, 0x63, 0),
393	HSPHY_INIT_CFG(0x9c, 0x03, 0),
394	HSPHY_INIT_CFG(0xa0, 0x1d, 0),
395	HSPHY_INIT_CFG(0xa4, 0x03, 0),
396	HSPHY_INIT_CFG(0x8c, 0x23, 0),
397	HSPHY_INIT_CFG(0x78, 0x08, 0),
398	HSPHY_INIT_CFG(0x7c, 0xdc, 0),
399	HSPHY_INIT_CFG(0x90, 0xe0, 20),
400	HSPHY_INIT_CFG(0x74, 0x10, 0),
401	HSPHY_INIT_CFG(0x90, 0x60, 0),
402};
403
404static const struct hsphy_data hsphy_data_femtophy = {
405	.init_seq = init_seq_femtophy,
406	.init_seq_num = ARRAY_SIZE(init_seq_femtophy),
407};
408
409static const struct of_device_id qcom_snps_hsphy_match[] = {
410	{ .compatible = "qcom,usb-hs-28nm-femtophy", .data = &hsphy_data_femtophy, },
411	{ },
412};
413MODULE_DEVICE_TABLE(of, qcom_snps_hsphy_match);
414
415static struct platform_driver qcom_snps_hsphy_driver = {
416	.probe = qcom_snps_hsphy_probe,
417	.driver	= {
418		.name = "qcom,usb-hs-28nm-phy",
419		.of_match_table = qcom_snps_hsphy_match,
420	},
421};
422module_platform_driver(qcom_snps_hsphy_driver);
423
424MODULE_DESCRIPTION("Qualcomm 28nm Hi-Speed USB PHY driver");
425MODULE_LICENSE("GPL v2");
426