mp9941.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Hardware monitoring driver for MPS Multi-phase Digital VR Controllers(MP9941)
  4 */
  5
  6#include <linux/bitfield.h>
  7#include <linux/bits.h>
  8#include <linux/i2c.h>
  9#include <linux/module.h>
 10#include <linux/of_device.h>
 11#include "pmbus.h"
 12
 13/*
 14 * Vender specific registers. The MFR_ICC_MAX(0x02) is used to
 15 * config the iin scale. The MFR_RESO_SET(0xC7) is used to
 16 * config the vout format. The MFR_VR_MULTI_CONFIG_R1(0x0D) is
 17 * used to identify the vout vid step.
 18 */
 19#define MFR_ICC_MAX	0x02
 20#define MFR_RESO_SET	0xC7
 21#define MFR_VR_MULTI_CONFIG_R1	0x0D
 22
 23#define MP9941_VIN_LIMIT_UINT	1
 24#define MP9941_VIN_LIMIT_DIV	8
 25#define MP9941_READ_VIN_UINT	1
 26#define MP9941_READ_VIN_DIV	32
 27
 28#define MP9941_PAGE_NUM	1
 29
 30#define MP9941_RAIL1_FUNC	(PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | \
 31							PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT | \
 32							PMBUS_HAVE_TEMP | PMBUS_HAVE_PIN | \
 33							PMBUS_HAVE_IIN | \
 34							PMBUS_HAVE_STATUS_VOUT | \
 35							PMBUS_HAVE_STATUS_IOUT | \
 36							PMBUS_HAVE_STATUS_TEMP | \
 37							PMBUS_HAVE_STATUS_INPUT)
 38
 39struct mp9941_data {
 40	struct pmbus_driver_info info;
 41	int vid_resolution;
 42};
 43
 44#define to_mp9941_data(x) container_of(x, struct mp9941_data, info)
 45
 46static int mp9941_set_vout_format(struct i2c_client *client)
 47{
 48	int ret;
 49
 50	ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
 51	if (ret < 0)
 52		return ret;
 53
 54	ret = i2c_smbus_read_word_data(client, MFR_RESO_SET);
 55	if (ret < 0)
 56		return ret;
 57
 58	/*
 59	 * page = 0, MFR_RESO_SET[7:6] defines the vout format
 60	 * 2'b11 set the vout format as direct
 61	 */
 62	ret = (ret & ~GENMASK(7, 6)) | FIELD_PREP(GENMASK(7, 6), 3);
 63
 64	return i2c_smbus_write_word_data(client, MFR_RESO_SET, ret);
 65}
 66
 67static int
 68mp9941_identify_vid_resolution(struct i2c_client *client, struct pmbus_driver_info *info)
 69{
 70	struct mp9941_data *data = to_mp9941_data(info);
 71	int ret;
 72
 73	/*
 74	 * page = 2, MFR_VR_MULTI_CONFIG_R1[4:4] defines rail1 vid step value
 75	 * 1'b0 represents the vid step value is 10mV
 76	 * 1'b1 represents the vid step value is 5mV
 77	 */
 78	ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 2);
 79	if (ret < 0)
 80		return ret;
 81
 82	ret = i2c_smbus_read_word_data(client, MFR_VR_MULTI_CONFIG_R1);
 83	if (ret < 0)
 84		return ret;
 85
 86	if (FIELD_GET(GENMASK(4, 4), ret))
 87		data->vid_resolution = 5;
 88	else
 89		data->vid_resolution = 10;
 90
 91	return 0;
 92}
 93
 94static int mp9941_identify_iin_scale(struct i2c_client *client)
 95{
 96	int ret;
 97
 98	ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
 99	if (ret < 0)
100		return ret;
101
102	ret = i2c_smbus_read_word_data(client, MFR_RESO_SET);
103	if (ret < 0)
104		return ret;
105
106	ret = (ret & ~GENMASK(3, 2)) | FIELD_PREP(GENMASK(3, 2), 0);
107
108	ret = i2c_smbus_write_word_data(client, MFR_RESO_SET, ret);
109	if (ret < 0)
110		return ret;
111
112	/*
113	 * page = 2, MFR_ICC_MAX[15:13] defines the iin scale
114	 * 3'b000 set the iout scale as 0.5A/Lsb
115	 */
116	ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 2);
117	if (ret < 0)
118		return ret;
119
120	ret = i2c_smbus_read_word_data(client, MFR_ICC_MAX);
121	if (ret < 0)
122		return ret;
123
124	ret = (ret & ~GENMASK(15, 13)) | FIELD_PREP(GENMASK(15, 13), 0);
125
126	return i2c_smbus_write_word_data(client, MFR_ICC_MAX, ret);
127}
128
129static int mp9941_identify(struct i2c_client *client, struct pmbus_driver_info *info)
130{
131	int ret;
132
133	ret = mp9941_identify_iin_scale(client);
134	if (ret < 0)
135		return ret;
136
137	ret = mp9941_identify_vid_resolution(client, info);
138	if (ret < 0)
139		return ret;
140
141	return mp9941_set_vout_format(client);
142}
143
144static int mp9941_read_word_data(struct i2c_client *client, int page, int phase,
145				 int reg)
146{
147	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
148	struct mp9941_data *data = to_mp9941_data(info);
149	int ret;
150
151	switch (reg) {
152	case PMBUS_READ_VIN:
153		/* The MP9941 vin scale is (1/32V)/Lsb */
154		ret = pmbus_read_word_data(client, page, phase, reg);
155		if (ret < 0)
156			return ret;
157
158		ret = DIV_ROUND_CLOSEST((ret & GENMASK(9, 0)) * MP9941_READ_VIN_UINT,
159					MP9941_READ_VIN_DIV);
160		break;
161	case PMBUS_READ_IIN:
162		ret = pmbus_read_word_data(client, page, phase, reg);
163		if (ret < 0)
164			return ret;
165
166		ret = ret & GENMASK(10, 0);
167		break;
168	case PMBUS_VIN_OV_FAULT_LIMIT:
169		/* The MP9941 vin ov limit scale is (1/8V)/Lsb */
170		ret = pmbus_read_word_data(client, page, phase, reg);
171		if (ret < 0)
172			return ret;
173
174		ret = DIV_ROUND_CLOSEST((ret & GENMASK(7, 0)) * MP9941_VIN_LIMIT_UINT,
175					MP9941_VIN_LIMIT_DIV);
176		break;
177	case PMBUS_IIN_OC_WARN_LIMIT:
178		ret = pmbus_read_word_data(client, page, phase, reg);
179		if (ret < 0)
180			return ret;
181
182		ret = ret & GENMASK(7, 0);
183		break;
184	case PMBUS_VOUT_UV_FAULT_LIMIT:
185	case PMBUS_MFR_VOUT_MIN:
186	case PMBUS_MFR_VOUT_MAX:
187		/*
188		 * The vout scale is set to 1mV/Lsb(using r/m/b scale).
189		 * But the vout uv limit and vout max/min scale is 1VID/Lsb,
190		 * so the vout uv limit and vout max/min value should be
191		 * multiplied by vid resolution.
192		 */
193		ret = pmbus_read_word_data(client, page, phase, reg);
194		if (ret < 0)
195			return ret;
196
197		ret = ret * data->vid_resolution;
198		break;
199	case PMBUS_READ_IOUT:
200	case PMBUS_READ_POUT:
201	case PMBUS_READ_TEMPERATURE_1:
202	case PMBUS_READ_VOUT:
203	case PMBUS_READ_PIN:
204	case PMBUS_OT_FAULT_LIMIT:
205	case PMBUS_OT_WARN_LIMIT:
206		ret = -ENODATA;
207		break;
208	default:
209		ret = -EINVAL;
210		break;
211	}
212
213	return ret;
214}
215
216static int mp9941_write_word_data(struct i2c_client *client, int page, int reg,
217				  u16 word)
218{
219	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
220	struct mp9941_data *data = to_mp9941_data(info);
221	int ret;
222
223	switch (reg) {
224	case PMBUS_VIN_OV_FAULT_LIMIT:
225		/* The MP9941 vin ov limit scale is (1/8V)/Lsb */
226		ret = pmbus_write_word_data(client, page, reg,
227					    DIV_ROUND_CLOSEST(word * MP9941_VIN_LIMIT_DIV,
228							      MP9941_VIN_LIMIT_UINT));
229		break;
230	case PMBUS_VOUT_UV_FAULT_LIMIT:
231	case PMBUS_MFR_VOUT_MIN:
232	case PMBUS_MFR_VOUT_MAX:
233		ret = pmbus_write_word_data(client, page, reg,
234					    DIV_ROUND_CLOSEST(word, data->vid_resolution));
235		break;
236	case PMBUS_IIN_OC_WARN_LIMIT:
237	case PMBUS_OT_FAULT_LIMIT:
238	case PMBUS_OT_WARN_LIMIT:
239		ret = -ENODATA;
240		break;
241	default:
242		ret = -EINVAL;
243		break;
244	}
245
246	return ret;
247}
248
249static const struct pmbus_driver_info mp9941_info = {
250	.pages = MP9941_PAGE_NUM,
251	.format[PSC_VOLTAGE_IN] = direct,
252	.format[PSC_CURRENT_IN] = direct,
253	.format[PSC_CURRENT_OUT] = linear,
254	.format[PSC_POWER] = linear,
255	.format[PSC_TEMPERATURE] = direct,
256	.format[PSC_VOLTAGE_OUT] = direct,
257
258	.m[PSC_TEMPERATURE] = 1,
259	.R[PSC_TEMPERATURE] = 0,
260	.b[PSC_TEMPERATURE] = 0,
261
262	.m[PSC_VOLTAGE_IN] = 1,
263	.R[PSC_VOLTAGE_IN] = 0,
264	.b[PSC_VOLTAGE_IN] = 0,
265
266	.m[PSC_CURRENT_IN] = 2,
267	.R[PSC_CURRENT_IN] = 0,
268	.b[PSC_CURRENT_IN] = 0,
269
270	.m[PSC_VOLTAGE_OUT] = 1,
271	.R[PSC_VOLTAGE_OUT] = 3,
272	.b[PSC_VOLTAGE_OUT] = 0,
273
274	.func[0] = MP9941_RAIL1_FUNC,
275	.read_word_data = mp9941_read_word_data,
276	.write_word_data = mp9941_write_word_data,
277	.identify = mp9941_identify,
278};
279
280static int mp9941_probe(struct i2c_client *client)
281{
282	struct mp9941_data *data;
283
284	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
285	if (!data)
286		return -ENOMEM;
287
288	memcpy(&data->info, &mp9941_info, sizeof(mp9941_info));
289
290	return pmbus_do_probe(client, &data->info);
291}
292
293static const struct i2c_device_id mp9941_id[] = {
294	{ "mp9941" },
295	{ }
296};
297MODULE_DEVICE_TABLE(i2c, mp9941_id);
298
299static const struct of_device_id __maybe_unused mp9941_of_match[] = {
300	{.compatible = "mps,mp9941"},
301	{}
302};
303MODULE_DEVICE_TABLE(of, mp9941_of_match);
304
305static struct i2c_driver mp9941_driver = {
306	.driver = {
307		.name = "mp9941",
308		.of_match_table = mp9941_of_match,
309	},
310	.probe = mp9941_probe,
311	.id_table = mp9941_id,
312};
313
314module_i2c_driver(mp9941_driver);
315
316MODULE_AUTHOR("Noah Wang <noahwang.wang@outlook.com>");
317MODULE_DESCRIPTION("PMBus driver for MPS MP9941");
318MODULE_LICENSE("GPL");
319MODULE_IMPORT_NS("PMBUS");