xref: /linux/drivers/hwmon/pmbus/mp9941.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 
39 struct 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 
46 static 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 
67 static int
68 mp9941_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 
94 static 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 
129 static 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 
144 static 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 
216 static 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 
249 static 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 
280 static 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 
293 static const struct i2c_device_id mp9941_id[] = {
294 	{ "mp9941" },
295 	{ }
296 };
297 MODULE_DEVICE_TABLE(i2c, mp9941_id);
298 
299 static const struct of_device_id __maybe_unused mp9941_of_match[] = {
300 	{.compatible = "mps,mp9941"},
301 	{}
302 };
303 MODULE_DEVICE_TABLE(of, mp9941_of_match);
304 
305 static 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 
314 module_i2c_driver(mp9941_driver);
315 
316 MODULE_AUTHOR("Noah Wang <noahwang.wang@outlook.com>");
317 MODULE_DESCRIPTION("PMBus driver for MPS MP9941");
318 MODULE_LICENSE("GPL");
319 MODULE_IMPORT_NS(PMBUS);
320