xref: /linux/drivers/usb/typec/mux/ptn36502.c (revision a96abf3bad810d4d281a3f47f1985a2470daa9ed)
1  // SPDX-License-Identifier: GPL-2.0+
2  /*
3   * NXP PTN36502 Type-C driver
4   *
5   * Copyright (C) 2023 Luca Weiss <luca.weiss@fairphone.com>
6   *
7   * Based on NB7VPQ904M driver:
8   * Copyright (C) 2023 Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
9   */
10  
11  #include <drm/bridge/aux-bridge.h>
12  #include <linux/bitfield.h>
13  #include <linux/i2c.h>
14  #include <linux/kernel.h>
15  #include <linux/module.h>
16  #include <linux/mutex.h>
17  #include <linux/of_graph.h>
18  #include <linux/regmap.h>
19  #include <linux/regulator/consumer.h>
20  #include <linux/usb/typec_dp.h>
21  #include <linux/usb/typec_mux.h>
22  #include <linux/usb/typec_retimer.h>
23  
24  #define PTN36502_CHIP_ID_REG				0x00
25  #define PTN36502_CHIP_ID				0x02
26  
27  #define PTN36502_CHIP_REVISION_REG			0x01
28  #define PTN36502_CHIP_REVISION_BASE_MASK		GENMASK(7, 4)
29  #define PTN36502_CHIP_REVISION_METAL_MASK		GENMASK(3, 0)
30  
31  #define PTN36502_DP_LINK_CTRL_REG			0x06
32  #define PTN36502_DP_LINK_CTRL_LANES_MASK		GENMASK(3, 2)
33  #define PTN36502_DP_LINK_CTRL_LANES_2			(2)
34  #define PTN36502_DP_LINK_CTRL_LANES_4			(3)
35  #define PTN36502_DP_LINK_CTRL_LINK_RATE_MASK		GENMASK(1, 0)
36  #define PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS		(2)
37  
38  /* Registers for lane 0 (0x07) to lane 3 (0x0a) have the same layout */
39  #define PTN36502_DP_LANE_CTRL_REG(n)			(0x07 + (n))
40  #define PTN36502_DP_LANE_CTRL_RX_GAIN_MASK		GENMASK(6, 4)
41  #define PTN36502_DP_LANE_CTRL_RX_GAIN_3DB		(2)
42  #define PTN36502_DP_LANE_CTRL_TX_SWING_MASK             GENMASK(3, 2)
43  #define PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD         (2)
44  #define PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_MASK		GENMASK(1, 0)
45  #define PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB	(1)
46  
47  #define PTN36502_MODE_CTRL1_REG				0x0b
48  #define PTN36502_MODE_CTRL1_PLUG_ORIENT_MASK		GENMASK(5, 5)
49  #define PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE		(1)
50  #define PTN36502_MODE_CTRL1_AUX_CROSSBAR_MASK		GENMASK(3, 3)
51  #define PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON		(1)
52  #define PTN36502_MODE_CTRL1_MODE_MASK			GENMASK(2, 0)
53  #define PTN36502_MODE_CTRL1_MODE_OFF			(0)
54  #define PTN36502_MODE_CTRL1_MODE_USB_ONLY		(1)
55  #define PTN36502_MODE_CTRL1_MODE_USB_DP			(2)
56  #define PTN36502_MODE_CTRL1_MODE_DP			(3)
57  
58  #define PTN36502_DEVICE_CTRL_REG			0x0d
59  #define PTN36502_DEVICE_CTRL_AUX_MONITORING_MASK	GENMASK(7, 7)
60  #define PTN36502_DEVICE_CTRL_AUX_MONITORING_EN		(1)
61  
62  struct ptn36502 {
63  	struct i2c_client *client;
64  	struct regulator *vdd18_supply;
65  	struct regmap *regmap;
66  	struct typec_switch_dev *sw;
67  	struct typec_retimer *retimer;
68  
69  	struct typec_switch *typec_switch;
70  	struct typec_mux *typec_mux;
71  
72  	struct mutex lock; /* protect non-concurrent retimer & switch */
73  
74  	enum typec_orientation orientation;
75  	unsigned long mode;
76  	unsigned int svid;
77  };
78  
79  static int ptn36502_set(struct ptn36502 *ptn)
80  {
81  	bool reverse = (ptn->orientation == TYPEC_ORIENTATION_REVERSE);
82  	unsigned int ctrl1_val = 0;
83  	unsigned int lane_ctrl_val = 0;
84  	unsigned int link_ctrl_val = 0;
85  
86  	switch (ptn->mode) {
87  	case TYPEC_STATE_SAFE:
88  		/* Deep power saving state */
89  		regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG,
90  			     FIELD_PREP(PTN36502_MODE_CTRL1_MODE_MASK,
91  					PTN36502_MODE_CTRL1_MODE_OFF));
92  		return 0;
93  
94  	case TYPEC_STATE_USB:
95  		/*
96  		 * Normal Orientation (CC1)
97  		 * A -> USB RX
98  		 * B -> USB TX
99  		 * C -> X
100  		 * D -> X
101  		 * Flipped Orientation (CC2)
102  		 * A -> X
103  		 * B -> X
104  		 * C -> USB TX
105  		 * D -> USB RX
106  		 */
107  
108  		/* USB 3.1 Gen 1 only */
109  		ctrl1_val = FIELD_PREP(PTN36502_MODE_CTRL1_MODE_MASK,
110  				       PTN36502_MODE_CTRL1_MODE_USB_ONLY);
111  		if (reverse)
112  			ctrl1_val |= FIELD_PREP(PTN36502_MODE_CTRL1_PLUG_ORIENT_MASK,
113  						PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE);
114  
115  		regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
116  		return 0;
117  
118  	default:
119  		if (ptn->svid != USB_TYPEC_DP_SID)
120  			return -EINVAL;
121  
122  		break;
123  	}
124  
125  	/* DP Altmode Setup */
126  
127  	switch (ptn->mode) {
128  	case TYPEC_DP_STATE_C:
129  	case TYPEC_DP_STATE_E:
130  		/*
131  		 * Normal Orientation (CC1)
132  		 * A -> DP3
133  		 * B -> DP2
134  		 * C -> DP1
135  		 * D -> DP0
136  		 * Flipped Orientation (CC2)
137  		 * A -> DP0
138  		 * B -> DP1
139  		 * C -> DP2
140  		 * D -> DP3
141  		 */
142  
143  		/* 4-lane DP */
144  		ctrl1_val |= FIELD_PREP(PTN36502_MODE_CTRL1_MODE_MASK,
145  					PTN36502_MODE_CTRL1_MODE_DP);
146  		link_ctrl_val |= FIELD_PREP(PTN36502_DP_LINK_CTRL_LANES_MASK,
147  					    PTN36502_DP_LINK_CTRL_LANES_4);
148  		break;
149  
150  	case TYPEC_DP_STATE_D:
151  	case TYPEC_DP_STATE_F: /* State F is deprecated */
152  		/*
153  		 * Normal Orientation (CC1)
154  		 * A -> USB RX
155  		 * B -> USB TX
156  		 * C -> DP1
157  		 * D -> DP0
158  		 * Flipped Orientation (CC2)
159  		 * A -> DP0
160  		 * B -> DP1
161  		 * C -> USB TX
162  		 * D -> USB RX
163  		 */
164  
165  		/* USB 3.1 Gen 1 and 2-lane DP */
166  		ctrl1_val |= FIELD_PREP(PTN36502_MODE_CTRL1_MODE_MASK,
167  					PTN36502_MODE_CTRL1_MODE_USB_DP);
168  		link_ctrl_val |= FIELD_PREP(PTN36502_DP_LINK_CTRL_LANES_MASK,
169  					    PTN36502_DP_LINK_CTRL_LANES_2);
170  		break;
171  
172  	default:
173  		return -EOPNOTSUPP;
174  	}
175  
176  	/* Enable AUX monitoring */
177  	regmap_write(ptn->regmap, PTN36502_DEVICE_CTRL_REG,
178  		     FIELD_PREP(PTN36502_DEVICE_CTRL_AUX_MONITORING_MASK,
179  				PTN36502_DEVICE_CTRL_AUX_MONITORING_EN));
180  
181  	/* Enable AUX switch path */
182  	ctrl1_val |= FIELD_PREP(PTN36502_MODE_CTRL1_AUX_CROSSBAR_MASK,
183  				PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON);
184  	if (reverse)
185  		ctrl1_val |= FIELD_PREP(PTN36502_MODE_CTRL1_PLUG_ORIENT_MASK,
186  					PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE);
187  	regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
188  
189  	/* DP Link rate: 5.4 Gbps (HBR2) */
190  	link_ctrl_val |= FIELD_PREP(PTN36502_DP_LINK_CTRL_LINK_RATE_MASK,
191  				    PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS);
192  	regmap_write(ptn->regmap, PTN36502_DP_LINK_CTRL_REG, link_ctrl_val);
193  
194  	/*
195  	 * For all lanes:
196  	 * - Rx equivalization gain: 3 dB
197  	 * - TX output swing control: 800 mVppd
198  	 * - Pre-emphasis control: 3.5 dB
199  	 */
200  	lane_ctrl_val = FIELD_PREP(PTN36502_DP_LANE_CTRL_RX_GAIN_MASK,
201  				   PTN36502_DP_LANE_CTRL_RX_GAIN_3DB) |
202  			FIELD_PREP(PTN36502_DP_LANE_CTRL_TX_SWING_MASK,
203  				   PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD) |
204  			FIELD_PREP(PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_MASK,
205  				   PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB);
206  	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(0), lane_ctrl_val);
207  	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(1), lane_ctrl_val);
208  	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(2), lane_ctrl_val);
209  	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(3), lane_ctrl_val);
210  
211  	return 0;
212  }
213  
214  static int ptn36502_sw_set(struct typec_switch_dev *sw, enum typec_orientation orientation)
215  {
216  	struct ptn36502 *ptn = typec_switch_get_drvdata(sw);
217  	int ret;
218  
219  	ret = typec_switch_set(ptn->typec_switch, orientation);
220  	if (ret)
221  		return ret;
222  
223  	mutex_lock(&ptn->lock);
224  
225  	if (ptn->orientation != orientation) {
226  		ptn->orientation = orientation;
227  
228  		ret = ptn36502_set(ptn);
229  	}
230  
231  	mutex_unlock(&ptn->lock);
232  
233  	return ret;
234  }
235  
236  static int ptn36502_retimer_set(struct typec_retimer *retimer, struct typec_retimer_state *state)
237  {
238  	struct ptn36502 *ptn = typec_retimer_get_drvdata(retimer);
239  	struct typec_mux_state mux_state;
240  	int ret = 0;
241  
242  	mutex_lock(&ptn->lock);
243  
244  	if (ptn->mode != state->mode) {
245  		ptn->mode = state->mode;
246  
247  		if (state->alt)
248  			ptn->svid = state->alt->svid;
249  		else
250  			ptn->svid = 0; // No SVID
251  
252  		ret = ptn36502_set(ptn);
253  	}
254  
255  	mutex_unlock(&ptn->lock);
256  
257  	if (ret)
258  		return ret;
259  
260  	mux_state.alt = state->alt;
261  	mux_state.data = state->data;
262  	mux_state.mode = state->mode;
263  
264  	return typec_mux_set(ptn->typec_mux, &mux_state);
265  }
266  
267  static int ptn36502_detect(struct ptn36502 *ptn)
268  {
269  	struct device *dev = &ptn->client->dev;
270  	unsigned int reg_val;
271  	int ret;
272  
273  	ret = regmap_read(ptn->regmap, PTN36502_CHIP_ID_REG,
274  			  &reg_val);
275  	if (ret < 0)
276  		return dev_err_probe(dev, ret, "Failed to read chip ID\n");
277  
278  	if (reg_val != PTN36502_CHIP_ID)
279  		return dev_err_probe(dev, -ENODEV, "Unexpected chip ID: %x\n", reg_val);
280  
281  	ret = regmap_read(ptn->regmap, PTN36502_CHIP_REVISION_REG,
282  			  &reg_val);
283  	if (ret < 0)
284  		return dev_err_probe(dev, ret, "Failed to read chip revision\n");
285  
286  	dev_dbg(dev, "Chip revision: base layer version %lx, metal layer version %lx\n",
287  		FIELD_GET(PTN36502_CHIP_REVISION_BASE_MASK, reg_val),
288  		FIELD_GET(PTN36502_CHIP_REVISION_METAL_MASK, reg_val));
289  
290  	return 0;
291  }
292  
293  static const struct regmap_config ptn36502_regmap = {
294  	.max_register = 0x0d,
295  	.reg_bits = 8,
296  	.val_bits = 8,
297  };
298  
299  static int ptn36502_probe(struct i2c_client *client)
300  {
301  	struct device *dev = &client->dev;
302  	struct typec_switch_desc sw_desc = { };
303  	struct typec_retimer_desc retimer_desc = { };
304  	struct ptn36502 *ptn;
305  	int ret;
306  
307  	ptn = devm_kzalloc(dev, sizeof(*ptn), GFP_KERNEL);
308  	if (!ptn)
309  		return -ENOMEM;
310  
311  	ptn->client = client;
312  
313  	ptn->regmap = devm_regmap_init_i2c(client, &ptn36502_regmap);
314  	if (IS_ERR(ptn->regmap)) {
315  		dev_err(&client->dev, "Failed to allocate register map\n");
316  		return PTR_ERR(ptn->regmap);
317  	}
318  
319  	ptn->mode = TYPEC_STATE_SAFE;
320  	ptn->orientation = TYPEC_ORIENTATION_NONE;
321  
322  	mutex_init(&ptn->lock);
323  
324  	ptn->vdd18_supply = devm_regulator_get_optional(dev, "vdd18");
325  	if (IS_ERR(ptn->vdd18_supply))
326  		return PTR_ERR(ptn->vdd18_supply);
327  
328  	ptn->typec_switch = fwnode_typec_switch_get(dev->fwnode);
329  	if (IS_ERR(ptn->typec_switch))
330  		return dev_err_probe(dev, PTR_ERR(ptn->typec_switch),
331  				     "Failed to acquire orientation-switch\n");
332  
333  	ptn->typec_mux = fwnode_typec_mux_get(dev->fwnode);
334  	if (IS_ERR(ptn->typec_mux)) {
335  		ret = dev_err_probe(dev, PTR_ERR(ptn->typec_mux),
336  				    "Failed to acquire mode-switch\n");
337  		goto err_switch_put;
338  	}
339  
340  	ret = regulator_enable(ptn->vdd18_supply);
341  	if (ret) {
342  		ret = dev_err_probe(dev, ret, "Failed to enable vdd18\n");
343  		goto err_mux_put;
344  	}
345  
346  	ret = ptn36502_detect(ptn);
347  	if (ret)
348  		goto err_disable_regulator;
349  
350  	ret = drm_aux_bridge_register(dev);
351  	if (ret)
352  		goto err_disable_regulator;
353  
354  	sw_desc.drvdata = ptn;
355  	sw_desc.fwnode = dev->fwnode;
356  	sw_desc.set = ptn36502_sw_set;
357  
358  	ptn->sw = typec_switch_register(dev, &sw_desc);
359  	if (IS_ERR(ptn->sw)) {
360  		ret = dev_err_probe(dev, PTR_ERR(ptn->sw),
361  				    "Failed to register typec switch\n");
362  		goto err_disable_regulator;
363  	}
364  
365  	retimer_desc.drvdata = ptn;
366  	retimer_desc.fwnode = dev->fwnode;
367  	retimer_desc.set = ptn36502_retimer_set;
368  
369  	ptn->retimer = typec_retimer_register(dev, &retimer_desc);
370  	if (IS_ERR(ptn->retimer)) {
371  		ret = dev_err_probe(dev, PTR_ERR(ptn->retimer),
372  				    "Failed to register typec retimer\n");
373  		goto err_switch_unregister;
374  	}
375  
376  	return 0;
377  
378  err_switch_unregister:
379  	typec_switch_unregister(ptn->sw);
380  
381  err_disable_regulator:
382  	regulator_disable(ptn->vdd18_supply);
383  
384  err_mux_put:
385  	typec_mux_put(ptn->typec_mux);
386  
387  err_switch_put:
388  	typec_switch_put(ptn->typec_switch);
389  
390  	return ret;
391  }
392  
393  static void ptn36502_remove(struct i2c_client *client)
394  {
395  	struct ptn36502 *ptn = i2c_get_clientdata(client);
396  
397  	typec_retimer_unregister(ptn->retimer);
398  	typec_switch_unregister(ptn->sw);
399  
400  	regulator_disable(ptn->vdd18_supply);
401  
402  	typec_mux_put(ptn->typec_mux);
403  	typec_switch_put(ptn->typec_switch);
404  }
405  
406  static const struct i2c_device_id ptn36502_table[] = {
407  	{ "ptn36502" },
408  	{ }
409  };
410  MODULE_DEVICE_TABLE(i2c, ptn36502_table);
411  
412  static const struct of_device_id ptn36502_of_table[] = {
413  	{ .compatible = "nxp,ptn36502" },
414  	{ }
415  };
416  MODULE_DEVICE_TABLE(of, ptn36502_of_table);
417  
418  static struct i2c_driver ptn36502_driver = {
419  	.driver = {
420  		.name = "ptn36502",
421  		.of_match_table = ptn36502_of_table,
422  	},
423  	.probe		= ptn36502_probe,
424  	.remove		= ptn36502_remove,
425  	.id_table	= ptn36502_table,
426  };
427  module_i2c_driver(ptn36502_driver);
428  
429  MODULE_AUTHOR("Luca Weiss <luca.weiss@fairphone.com>");
430  MODULE_DESCRIPTION("NXP PTN36502 Type-C driver");
431  MODULE_LICENSE("GPL");
432