ptn36502.c

  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
 62struct 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
 79static 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
214static 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
236static 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
267static 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
293static const struct regmap_config ptn36502_regmap = {
294	.max_register = 0x0d,
295	.reg_bits = 8,
296	.val_bits = 8,
297};
298
299static 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
378err_switch_unregister:
379	typec_switch_unregister(ptn->sw);
380
381err_disable_regulator:
382	regulator_disable(ptn->vdd18_supply);
383
384err_mux_put:
385	typec_mux_put(ptn->typec_mux);
386
387err_switch_put:
388	typec_switch_put(ptn->typec_switch);
389
390	return ret;
391}
392
393static 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
406static const struct i2c_device_id ptn36502_table[] = {
407	{ "ptn36502" },
408	{ }
409};
410MODULE_DEVICE_TABLE(i2c, ptn36502_table);
411
412static const struct of_device_id ptn36502_of_table[] = {
413	{ .compatible = "nxp,ptn36502" },
414	{ }
415};
416MODULE_DEVICE_TABLE(of, ptn36502_of_table);
417
418static 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};
427module_i2c_driver(ptn36502_driver);
428
429MODULE_AUTHOR("Luca Weiss <luca.weiss@fairphone.com>");
430MODULE_DESCRIPTION("NXP PTN36502 Type-C driver");
431MODULE_LICENSE("GPL");