1 // SPDX-License-Identifier: GPL-2.0+
2 /* Copyright (c) 2017 NXP. */
3 
4 #include <linux/bitfield.h>
5 #include <linux/clk.h>
6 #include <linux/delay.h>
7 #include <linux/io.h>
8 #include <linux/module.h>
9 #include <linux/of.h>
10 #include <linux/phy/phy.h>
11 #include <linux/platform_device.h>
12 #include <linux/regulator/consumer.h>
13 
14 #define PHY_CTRL0			0x0
15 #define PHY_CTRL0_REF_SSP_EN		BIT(2)
16 #define PHY_CTRL0_FSEL_MASK		GENMASK(10, 5)
17 #define PHY_CTRL0_FSEL_24M		0x2a
18 
19 #define PHY_CTRL1			0x4
20 #define PHY_CTRL1_RESET			BIT(0)
21 #define PHY_CTRL1_COMMONONN		BIT(1)
22 #define PHY_CTRL1_ATERESET		BIT(3)
23 #define PHY_CTRL1_VDATSRCENB0		BIT(19)
24 #define PHY_CTRL1_VDATDETENB0		BIT(20)
25 
26 #define PHY_CTRL2			0x8
27 #define PHY_CTRL2_TXENABLEN0		BIT(8)
28 #define PHY_CTRL2_OTG_DISABLE		BIT(9)
29 
30 #define PHY_CTRL3			0xc
31 #define PHY_CTRL3_COMPDISTUNE_MASK	GENMASK(2, 0)
32 #define PHY_CTRL3_TXPREEMP_TUNE_MASK	GENMASK(16, 15)
33 #define PHY_CTRL3_TXRISE_TUNE_MASK	GENMASK(21, 20)
34 #define PHY_CTRL3_TXVREF_TUNE_MASK	GENMASK(25, 22)
35 #define PHY_CTRL3_TX_VBOOST_LEVEL_MASK	GENMASK(31, 29)
36 
37 #define PHY_CTRL4			0x10
38 #define PHY_CTRL4_PCS_TX_DEEMPH_3P5DB_MASK	GENMASK(20, 15)
39 
40 #define PHY_CTRL5			0x14
41 #define PHY_CTRL5_DMPWD_OVERRIDE_SEL	BIT(23)
42 #define PHY_CTRL5_DMPWD_OVERRIDE	BIT(22)
43 #define PHY_CTRL5_DPPWD_OVERRIDE_SEL	BIT(21)
44 #define PHY_CTRL5_DPPWD_OVERRIDE	BIT(20)
45 #define PHY_CTRL5_PCS_TX_SWING_FULL_MASK	GENMASK(6, 0)
46 
47 #define PHY_CTRL6			0x18
48 #define PHY_CTRL6_ALT_CLK_EN		BIT(1)
49 #define PHY_CTRL6_ALT_CLK_SEL		BIT(0)
50 
51 #define PHY_TUNE_DEFAULT		0xffffffff
52 
53 struct imx8mq_usb_phy {
54 	struct phy *phy;
55 	struct clk *clk;
56 	void __iomem *base;
57 	struct regulator *vbus;
58 	u32 pcs_tx_swing_full;
59 	u32 pcs_tx_deemph_3p5db;
60 	u32 tx_vref_tune;
61 	u32 tx_rise_tune;
62 	u32 tx_preemp_amp_tune;
63 	u32 tx_vboost_level;
64 	u32 comp_dis_tune;
65 };
66 
phy_tx_vref_tune_from_property(u32 percent)67 static u32 phy_tx_vref_tune_from_property(u32 percent)
68 {
69 	percent = clamp(percent, 94U, 124U);
70 
71 	return DIV_ROUND_CLOSEST(percent - 94U, 2);
72 }
73 
phy_tx_rise_tune_from_property(u32 percent)74 static u32 phy_tx_rise_tune_from_property(u32 percent)
75 {
76 	switch (percent) {
77 	case 0 ... 98:
78 		return 3;
79 	case 99:
80 		return 2;
81 	case 100 ... 101:
82 		return 1;
83 	default:
84 		return 0;
85 	}
86 }
87 
phy_tx_preemp_amp_tune_from_property(u32 microamp)88 static u32 phy_tx_preemp_amp_tune_from_property(u32 microamp)
89 {
90 	microamp = min(microamp, 1800U);
91 
92 	return microamp / 600;
93 }
94 
phy_tx_vboost_level_from_property(u32 microvolt)95 static u32 phy_tx_vboost_level_from_property(u32 microvolt)
96 {
97 	switch (microvolt) {
98 	case 0 ... 960:
99 		return 0;
100 	case 961 ... 1160:
101 		return 2;
102 	default:
103 		return 3;
104 	}
105 }
106 
phy_pcs_tx_deemph_3p5db_from_property(u32 decibel)107 static u32 phy_pcs_tx_deemph_3p5db_from_property(u32 decibel)
108 {
109 	return min(decibel, 36U);
110 }
111 
phy_comp_dis_tune_from_property(u32 percent)112 static u32 phy_comp_dis_tune_from_property(u32 percent)
113 {
114 	switch (percent) {
115 	case 0 ... 92:
116 		return 0;
117 	case 93 ... 95:
118 		return 1;
119 	case 96 ... 97:
120 		return 2;
121 	case 98 ... 102:
122 		return 3;
123 	case 103 ... 105:
124 		return 4;
125 	case 106 ... 109:
126 		return 5;
127 	case 110 ... 113:
128 		return 6;
129 	default:
130 		return 7;
131 	}
132 }
phy_pcs_tx_swing_full_from_property(u32 percent)133 static u32 phy_pcs_tx_swing_full_from_property(u32 percent)
134 {
135 	percent = min(percent, 100U);
136 
137 	return (percent * 127) / 100;
138 }
139 
imx8m_get_phy_tuning_data(struct imx8mq_usb_phy * imx_phy)140 static void imx8m_get_phy_tuning_data(struct imx8mq_usb_phy *imx_phy)
141 {
142 	struct device *dev = imx_phy->phy->dev.parent;
143 
144 	if (device_property_read_u32(dev, "fsl,phy-tx-vref-tune-percent",
145 				     &imx_phy->tx_vref_tune))
146 		imx_phy->tx_vref_tune = PHY_TUNE_DEFAULT;
147 	else
148 		imx_phy->tx_vref_tune =
149 			phy_tx_vref_tune_from_property(imx_phy->tx_vref_tune);
150 
151 	if (device_property_read_u32(dev, "fsl,phy-tx-rise-tune-percent",
152 				     &imx_phy->tx_rise_tune))
153 		imx_phy->tx_rise_tune = PHY_TUNE_DEFAULT;
154 	else
155 		imx_phy->tx_rise_tune =
156 			phy_tx_rise_tune_from_property(imx_phy->tx_rise_tune);
157 
158 	if (device_property_read_u32(dev, "fsl,phy-tx-preemp-amp-tune-microamp",
159 				     &imx_phy->tx_preemp_amp_tune))
160 		imx_phy->tx_preemp_amp_tune = PHY_TUNE_DEFAULT;
161 	else
162 		imx_phy->tx_preemp_amp_tune =
163 			phy_tx_preemp_amp_tune_from_property(imx_phy->tx_preemp_amp_tune);
164 
165 	if (device_property_read_u32(dev, "fsl,phy-tx-vboost-level-microvolt",
166 				     &imx_phy->tx_vboost_level))
167 		imx_phy->tx_vboost_level = PHY_TUNE_DEFAULT;
168 	else
169 		imx_phy->tx_vboost_level =
170 			phy_tx_vboost_level_from_property(imx_phy->tx_vboost_level);
171 
172 	if (device_property_read_u32(dev, "fsl,phy-comp-dis-tune-percent",
173 				     &imx_phy->comp_dis_tune))
174 		imx_phy->comp_dis_tune = PHY_TUNE_DEFAULT;
175 	else
176 		imx_phy->comp_dis_tune =
177 			phy_comp_dis_tune_from_property(imx_phy->comp_dis_tune);
178 
179 	if (device_property_read_u32(dev, "fsl,phy-pcs-tx-deemph-3p5db-attenuation-db",
180 				     &imx_phy->pcs_tx_deemph_3p5db))
181 		imx_phy->pcs_tx_deemph_3p5db = PHY_TUNE_DEFAULT;
182 	else
183 		imx_phy->pcs_tx_deemph_3p5db =
184 			phy_pcs_tx_deemph_3p5db_from_property(imx_phy->pcs_tx_deemph_3p5db);
185 
186 	if (device_property_read_u32(dev, "fsl,phy-pcs-tx-swing-full-percent",
187 				     &imx_phy->pcs_tx_swing_full))
188 		imx_phy->pcs_tx_swing_full = PHY_TUNE_DEFAULT;
189 	else
190 		imx_phy->pcs_tx_swing_full =
191 			phy_pcs_tx_swing_full_from_property(imx_phy->pcs_tx_swing_full);
192 }
193 
imx8m_phy_tune(struct imx8mq_usb_phy * imx_phy)194 static void imx8m_phy_tune(struct imx8mq_usb_phy *imx_phy)
195 {
196 	u32 value;
197 
198 	/* PHY tuning */
199 	if (imx_phy->pcs_tx_deemph_3p5db != PHY_TUNE_DEFAULT) {
200 		value = readl(imx_phy->base + PHY_CTRL4);
201 		value &= ~PHY_CTRL4_PCS_TX_DEEMPH_3P5DB_MASK;
202 		value |= FIELD_PREP(PHY_CTRL4_PCS_TX_DEEMPH_3P5DB_MASK,
203 				   imx_phy->pcs_tx_deemph_3p5db);
204 		writel(value, imx_phy->base + PHY_CTRL4);
205 	}
206 
207 	if (imx_phy->pcs_tx_swing_full != PHY_TUNE_DEFAULT) {
208 		value = readl(imx_phy->base + PHY_CTRL5);
209 		value |= FIELD_PREP(PHY_CTRL5_PCS_TX_SWING_FULL_MASK,
210 				   imx_phy->pcs_tx_swing_full);
211 		writel(value, imx_phy->base + PHY_CTRL5);
212 	}
213 
214 	if ((imx_phy->tx_vref_tune & imx_phy->tx_rise_tune &
215 	     imx_phy->tx_preemp_amp_tune & imx_phy->comp_dis_tune &
216 	     imx_phy->tx_vboost_level) == PHY_TUNE_DEFAULT)
217 		/* If all are the default values, no need update. */
218 		return;
219 
220 	value = readl(imx_phy->base + PHY_CTRL3);
221 
222 	if (imx_phy->tx_vref_tune != PHY_TUNE_DEFAULT) {
223 		value &= ~PHY_CTRL3_TXVREF_TUNE_MASK;
224 		value |= FIELD_PREP(PHY_CTRL3_TXVREF_TUNE_MASK,
225 				   imx_phy->tx_vref_tune);
226 	}
227 
228 	if (imx_phy->tx_rise_tune != PHY_TUNE_DEFAULT) {
229 		value &= ~PHY_CTRL3_TXRISE_TUNE_MASK;
230 		value |= FIELD_PREP(PHY_CTRL3_TXRISE_TUNE_MASK,
231 				    imx_phy->tx_rise_tune);
232 	}
233 
234 	if (imx_phy->tx_preemp_amp_tune != PHY_TUNE_DEFAULT) {
235 		value &= ~PHY_CTRL3_TXPREEMP_TUNE_MASK;
236 		value |= FIELD_PREP(PHY_CTRL3_TXPREEMP_TUNE_MASK,
237 				imx_phy->tx_preemp_amp_tune);
238 	}
239 
240 	if (imx_phy->comp_dis_tune != PHY_TUNE_DEFAULT) {
241 		value &= ~PHY_CTRL3_COMPDISTUNE_MASK;
242 		value |= FIELD_PREP(PHY_CTRL3_COMPDISTUNE_MASK,
243 				    imx_phy->comp_dis_tune);
244 	}
245 
246 	if (imx_phy->tx_vboost_level != PHY_TUNE_DEFAULT) {
247 		value &= ~PHY_CTRL3_TX_VBOOST_LEVEL_MASK;
248 		value |= FIELD_PREP(PHY_CTRL3_TX_VBOOST_LEVEL_MASK,
249 				    imx_phy->tx_vboost_level);
250 	}
251 
252 	writel(value, imx_phy->base + PHY_CTRL3);
253 }
254 
imx8mq_usb_phy_init(struct phy * phy)255 static int imx8mq_usb_phy_init(struct phy *phy)
256 {
257 	struct imx8mq_usb_phy *imx_phy = phy_get_drvdata(phy);
258 	u32 value;
259 
260 	value = readl(imx_phy->base + PHY_CTRL1);
261 	value &= ~(PHY_CTRL1_VDATSRCENB0 | PHY_CTRL1_VDATDETENB0 |
262 		   PHY_CTRL1_COMMONONN);
263 	value |= PHY_CTRL1_RESET | PHY_CTRL1_ATERESET;
264 	writel(value, imx_phy->base + PHY_CTRL1);
265 
266 	value = readl(imx_phy->base + PHY_CTRL0);
267 	value |= PHY_CTRL0_REF_SSP_EN;
268 	writel(value, imx_phy->base + PHY_CTRL0);
269 
270 	value = readl(imx_phy->base + PHY_CTRL2);
271 	value |= PHY_CTRL2_TXENABLEN0;
272 	writel(value, imx_phy->base + PHY_CTRL2);
273 
274 	value = readl(imx_phy->base + PHY_CTRL1);
275 	value &= ~(PHY_CTRL1_RESET | PHY_CTRL1_ATERESET);
276 	writel(value, imx_phy->base + PHY_CTRL1);
277 
278 	return 0;
279 }
280 
imx8mp_usb_phy_init(struct phy * phy)281 static int imx8mp_usb_phy_init(struct phy *phy)
282 {
283 	struct imx8mq_usb_phy *imx_phy = phy_get_drvdata(phy);
284 	u32 value;
285 
286 	/* USB3.0 PHY signal fsel for 24M ref */
287 	value = readl(imx_phy->base + PHY_CTRL0);
288 	value &= ~PHY_CTRL0_FSEL_MASK;
289 	value |= FIELD_PREP(PHY_CTRL0_FSEL_MASK, PHY_CTRL0_FSEL_24M);
290 	writel(value, imx_phy->base + PHY_CTRL0);
291 
292 	/* Disable alt_clk_en and use internal MPLL clocks */
293 	value = readl(imx_phy->base + PHY_CTRL6);
294 	value &= ~(PHY_CTRL6_ALT_CLK_SEL | PHY_CTRL6_ALT_CLK_EN);
295 	writel(value, imx_phy->base + PHY_CTRL6);
296 
297 	value = readl(imx_phy->base + PHY_CTRL1);
298 	value &= ~(PHY_CTRL1_VDATSRCENB0 | PHY_CTRL1_VDATDETENB0);
299 	value |= PHY_CTRL1_RESET | PHY_CTRL1_ATERESET;
300 	writel(value, imx_phy->base + PHY_CTRL1);
301 
302 	value = readl(imx_phy->base + PHY_CTRL0);
303 	value |= PHY_CTRL0_REF_SSP_EN;
304 	writel(value, imx_phy->base + PHY_CTRL0);
305 
306 	value = readl(imx_phy->base + PHY_CTRL2);
307 	value |= PHY_CTRL2_TXENABLEN0 | PHY_CTRL2_OTG_DISABLE;
308 	writel(value, imx_phy->base + PHY_CTRL2);
309 
310 	udelay(10);
311 
312 	value = readl(imx_phy->base + PHY_CTRL1);
313 	value &= ~(PHY_CTRL1_RESET | PHY_CTRL1_ATERESET);
314 	writel(value, imx_phy->base + PHY_CTRL1);
315 
316 	imx8m_phy_tune(imx_phy);
317 
318 	return 0;
319 }
320 
imx8mq_phy_power_on(struct phy * phy)321 static int imx8mq_phy_power_on(struct phy *phy)
322 {
323 	struct imx8mq_usb_phy *imx_phy = phy_get_drvdata(phy);
324 	int ret;
325 
326 	ret = regulator_enable(imx_phy->vbus);
327 	if (ret)
328 		return ret;
329 
330 	return clk_prepare_enable(imx_phy->clk);
331 }
332 
imx8mq_phy_power_off(struct phy * phy)333 static int imx8mq_phy_power_off(struct phy *phy)
334 {
335 	struct imx8mq_usb_phy *imx_phy = phy_get_drvdata(phy);
336 
337 	clk_disable_unprepare(imx_phy->clk);
338 	regulator_disable(imx_phy->vbus);
339 
340 	return 0;
341 }
342 
343 static const struct phy_ops imx8mq_usb_phy_ops = {
344 	.init		= imx8mq_usb_phy_init,
345 	.power_on	= imx8mq_phy_power_on,
346 	.power_off	= imx8mq_phy_power_off,
347 	.owner		= THIS_MODULE,
348 };
349 
350 static const struct phy_ops imx8mp_usb_phy_ops = {
351 	.init		= imx8mp_usb_phy_init,
352 	.power_on	= imx8mq_phy_power_on,
353 	.power_off	= imx8mq_phy_power_off,
354 	.owner		= THIS_MODULE,
355 };
356 
357 static const struct of_device_id imx8mq_usb_phy_of_match[] = {
358 	{.compatible = "fsl,imx8mq-usb-phy",
359 	 .data = &imx8mq_usb_phy_ops,},
360 	{.compatible = "fsl,imx8mp-usb-phy",
361 	 .data = &imx8mp_usb_phy_ops,},
362 	{ }
363 };
364 MODULE_DEVICE_TABLE(of, imx8mq_usb_phy_of_match);
365 
imx8mq_usb_phy_probe(struct platform_device * pdev)366 static int imx8mq_usb_phy_probe(struct platform_device *pdev)
367 {
368 	struct phy_provider *phy_provider;
369 	struct device *dev = &pdev->dev;
370 	struct imx8mq_usb_phy *imx_phy;
371 	const struct phy_ops *phy_ops;
372 
373 	imx_phy = devm_kzalloc(dev, sizeof(*imx_phy), GFP_KERNEL);
374 	if (!imx_phy)
375 		return -ENOMEM;
376 
377 	imx_phy->clk = devm_clk_get(dev, "phy");
378 	if (IS_ERR(imx_phy->clk)) {
379 		dev_err(dev, "failed to get imx8mq usb phy clock\n");
380 		return PTR_ERR(imx_phy->clk);
381 	}
382 
383 	imx_phy->base = devm_platform_ioremap_resource(pdev, 0);
384 	if (IS_ERR(imx_phy->base))
385 		return PTR_ERR(imx_phy->base);
386 
387 	phy_ops = of_device_get_match_data(dev);
388 	if (!phy_ops)
389 		return -EINVAL;
390 
391 	imx_phy->phy = devm_phy_create(dev, NULL, phy_ops);
392 	if (IS_ERR(imx_phy->phy))
393 		return PTR_ERR(imx_phy->phy);
394 
395 	imx_phy->vbus = devm_regulator_get(dev, "vbus");
396 	if (IS_ERR(imx_phy->vbus))
397 		return dev_err_probe(dev, PTR_ERR(imx_phy->vbus), "failed to get vbus\n");
398 
399 	phy_set_drvdata(imx_phy->phy, imx_phy);
400 
401 	imx8m_get_phy_tuning_data(imx_phy);
402 
403 	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
404 
405 	return PTR_ERR_OR_ZERO(phy_provider);
406 }
407 
408 static struct platform_driver imx8mq_usb_phy_driver = {
409 	.probe	= imx8mq_usb_phy_probe,
410 	.driver = {
411 		.name	= "imx8mq-usb-phy",
412 		.of_match_table	= imx8mq_usb_phy_of_match,
413 	}
414 };
415 module_platform_driver(imx8mq_usb_phy_driver);
416 
417 MODULE_DESCRIPTION("FSL IMX8MQ USB PHY driver");
418 MODULE_LICENSE("GPL");
419