1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Hardware monitoring driver for MPS Multi-phase Digital VR Controllers(MP2925) 4 */ 5 6 #include <linux/bitfield.h> 7 #include <linux/i2c.h> 8 #include <linux/module.h> 9 #include <linux/of_device.h> 10 #include "pmbus.h" 11 12 /* 13 * Vender specific register MFR_VR_MULTI_CONFIG(0x08). 14 * This register is used to obtain vid scale. 15 */ 16 #define MFR_VR_MULTI_CONFIG 0x08 17 18 #define MP2925_VOUT_DIV 512 19 #define MP2925_VOUT_OVUV_UINT 195 20 #define MP2925_VOUT_OVUV_DIV 100 21 22 #define MP2925_PAGE_NUM 2 23 24 #define MP2925_RAIL1_FUNC (PMBUS_HAVE_VIN | PMBUS_HAVE_PIN | \ 25 PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | \ 26 PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP | \ 27 PMBUS_HAVE_STATUS_VOUT | \ 28 PMBUS_HAVE_STATUS_IOUT | \ 29 PMBUS_HAVE_STATUS_TEMP | \ 30 PMBUS_HAVE_STATUS_INPUT) 31 32 #define MP2925_RAIL2_FUNC (PMBUS_HAVE_PIN | PMBUS_HAVE_VOUT | \ 33 PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT | \ 34 PMBUS_HAVE_TEMP | PMBUS_HAVE_IIN | \ 35 PMBUS_HAVE_STATUS_VOUT | \ 36 PMBUS_HAVE_STATUS_IOUT | \ 37 PMBUS_HAVE_STATUS_TEMP | \ 38 PMBUS_HAVE_STATUS_INPUT) 39 40 struct mp2925_data { 41 struct pmbus_driver_info info; 42 int vout_scale[MP2925_PAGE_NUM]; 43 int vid_offset[MP2925_PAGE_NUM]; 44 }; 45 46 #define to_mp2925_data(x) container_of(x, struct mp2925_data, info) 47 48 static u16 mp2925_linear_exp_transfer(u16 word, u16 expect_exponent) 49 { 50 s16 exponent, mantissa, target_exponent; 51 52 exponent = ((s16)word) >> 11; 53 mantissa = ((s16)((word & 0x7ff) << 5)) >> 5; 54 target_exponent = (s16)((expect_exponent & 0x1f) << 11) >> 11; 55 56 if (exponent > target_exponent) 57 mantissa = mantissa << (exponent - target_exponent); 58 else 59 mantissa = mantissa >> (target_exponent - exponent); 60 61 return (mantissa & 0x7ff) | ((expect_exponent << 11) & 0xf800); 62 } 63 64 static int mp2925_read_byte_data(struct i2c_client *client, int page, int reg) 65 { 66 int ret; 67 68 switch (reg) { 69 case PMBUS_VOUT_MODE: 70 /* 71 * The MP2925 does not follow standard PMBus protocol completely, 72 * and the calculation of vout in this driver is based on direct 73 * format. As a result, the format of vout is enforced to direct. 74 */ 75 ret = PB_VOUT_MODE_DIRECT; 76 break; 77 default: 78 ret = -ENODATA; 79 break; 80 } 81 82 return ret; 83 } 84 85 static int mp2925_read_word_data(struct i2c_client *client, int page, int phase, 86 int reg) 87 { 88 const struct pmbus_driver_info *info = pmbus_get_driver_info(client); 89 struct mp2925_data *data = to_mp2925_data(info); 90 int ret; 91 92 switch (reg) { 93 case PMBUS_READ_VOUT: 94 ret = pmbus_read_word_data(client, page, phase, reg); 95 if (ret < 0) 96 return ret; 97 98 /* 99 * In vid mode, the MP2925 vout telemetry has 49 vid step offset, but 100 * PMBUS_VOUT_OV_FAULT_LIMIT and PMBUS_VOUT_UV_FAULT_LIMIT do not take 101 * this into consideration, its resolution is 1.95mV/LSB, as a result, 102 * format[PSC_VOLTAGE_OUT] can not be set to vid directly. Adding extra 103 * vid_offset variable for vout telemetry. 104 */ 105 ret = DIV_ROUND_CLOSEST(((ret & GENMASK(11, 0)) + data->vid_offset[page]) * 106 data->vout_scale[page], MP2925_VOUT_DIV); 107 break; 108 case PMBUS_VOUT_OV_FAULT_LIMIT: 109 case PMBUS_VOUT_UV_FAULT_LIMIT: 110 ret = pmbus_read_word_data(client, page, phase, reg); 111 if (ret < 0) 112 return ret; 113 114 ret = DIV_ROUND_CLOSEST((ret & GENMASK(11, 0)) * MP2925_VOUT_OVUV_UINT, 115 MP2925_VOUT_OVUV_DIV); 116 break; 117 case PMBUS_STATUS_WORD: 118 case PMBUS_READ_VIN: 119 case PMBUS_READ_IOUT: 120 case PMBUS_READ_POUT: 121 case PMBUS_READ_PIN: 122 case PMBUS_READ_IIN: 123 case PMBUS_READ_TEMPERATURE_1: 124 case PMBUS_VIN_OV_FAULT_LIMIT: 125 case PMBUS_VIN_OV_WARN_LIMIT: 126 case PMBUS_VIN_UV_WARN_LIMIT: 127 case PMBUS_VIN_UV_FAULT_LIMIT: 128 case PMBUS_IOUT_OC_FAULT_LIMIT: 129 case PMBUS_IOUT_OC_WARN_LIMIT: 130 case PMBUS_OT_FAULT_LIMIT: 131 case PMBUS_OT_WARN_LIMIT: 132 ret = -ENODATA; 133 break; 134 default: 135 ret = -EINVAL; 136 break; 137 } 138 139 return ret; 140 } 141 142 static int mp2925_write_word_data(struct i2c_client *client, int page, int reg, 143 u16 word) 144 { 145 int ret; 146 147 switch (reg) { 148 case PMBUS_VIN_OV_FAULT_LIMIT: 149 case PMBUS_VIN_OV_WARN_LIMIT: 150 case PMBUS_VIN_UV_WARN_LIMIT: 151 case PMBUS_VIN_UV_FAULT_LIMIT: 152 /* 153 * The PMBUS_VIN_OV_FAULT_LIMIT, PMBUS_VIN_OV_WARN_LIMIT, 154 * PMBUS_VIN_UV_WARN_LIMIT and PMBUS_VIN_UV_FAULT_LIMIT 155 * of MP2925 is linear11 format, and the exponent is a 156 * constant value(5'b11100)， so the exponent of word 157 * parameter should be converted to 5'b11100(0x1C). 158 */ 159 ret = pmbus_write_word_data(client, page, reg, 160 mp2925_linear_exp_transfer(word, 0x1C)); 161 break; 162 case PMBUS_VOUT_OV_FAULT_LIMIT: 163 case PMBUS_VOUT_UV_FAULT_LIMIT: 164 /* 165 * The bit0-bit11 is the limit value, and bit12-bit15 166 * should not be changed. 167 */ 168 ret = pmbus_read_word_data(client, page, 0xff, reg); 169 if (ret < 0) 170 return ret; 171 172 ret = pmbus_write_word_data(client, page, reg, 173 (ret & ~GENMASK(11, 0)) | 174 FIELD_PREP(GENMASK(11, 0), 175 DIV_ROUND_CLOSEST(word * MP2925_VOUT_OVUV_DIV, 176 MP2925_VOUT_OVUV_UINT))); 177 break; 178 case PMBUS_OT_FAULT_LIMIT: 179 case PMBUS_OT_WARN_LIMIT: 180 /* 181 * The PMBUS_OT_FAULT_LIMIT and PMBUS_OT_WARN_LIMIT of 182 * MP2925 is linear11 format, and the exponent is a 183 * constant value(5'b00000), so the exponent of word 184 * parameter should be converted to 5'b00000. 185 */ 186 ret = pmbus_write_word_data(client, page, reg, 187 mp2925_linear_exp_transfer(word, 0x00)); 188 break; 189 case PMBUS_IOUT_OC_FAULT_LIMIT: 190 case PMBUS_IOUT_OC_WARN_LIMIT: 191 /* 192 * The PMBUS_IOUT_OC_FAULT_LIMIT and PMBUS_IOUT_OC_WARN_LIMIT 193 * of MP2925 is linear11 format, and the exponent can not be 194 * changed. 195 */ 196 ret = pmbus_read_word_data(client, page, 0xff, reg); 197 if (ret < 0) 198 return ret; 199 200 ret = pmbus_write_word_data(client, page, reg, 201 mp2925_linear_exp_transfer(word, 202 FIELD_GET(GENMASK(15, 11), 203 ret))); 204 break; 205 default: 206 ret = -EINVAL; 207 break; 208 } 209 210 return ret; 211 } 212 213 static int 214 mp2925_identify_vout_scale(struct i2c_client *client, struct pmbus_driver_info *info, 215 int page) 216 { 217 struct mp2925_data *data = to_mp2925_data(info); 218 int ret; 219 220 ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page); 221 if (ret < 0) 222 return ret; 223 224 ret = i2c_smbus_read_byte_data(client, PMBUS_VOUT_MODE); 225 if (ret < 0) 226 return ret; 227 228 if (FIELD_GET(GENMASK(5, 5), ret)) { 229 ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 230 page == 0 ? 3 : 4); 231 if (ret < 0) 232 return ret; 233 234 ret = i2c_smbus_read_word_data(client, MFR_VR_MULTI_CONFIG); 235 if (ret < 0) 236 return ret; 237 238 if (FIELD_GET(GENMASK(5, 5), ret)) 239 data->vout_scale[page] = 2560; 240 else 241 data->vout_scale[page] = 5120; 242 243 /* 244 * In vid mode, the MP2925 vout telemetry has 49 vid step offset, but 245 * PMBUS_VOUT_OV_FAULT_LIMIT and PMBUS_VOUT_UV_FAULT_LIMIT do not take 246 * this into consideration, its resolution is 1.95mV/LSB, as a result, 247 * format[PSC_VOLTAGE_OUT] can not be set to vid directly. Adding extra 248 * vid_offset variable for vout telemetry. 249 */ 250 data->vid_offset[page] = 49; 251 } else if (FIELD_GET(GENMASK(4, 4), ret)) { 252 data->vout_scale[page] = 1; 253 data->vid_offset[page] = 0; 254 } else { 255 data->vout_scale[page] = 512; 256 data->vid_offset[page] = 0; 257 } 258 259 return 0; 260 } 261 262 static int mp2925_identify(struct i2c_client *client, struct pmbus_driver_info *info) 263 { 264 int ret; 265 266 ret = mp2925_identify_vout_scale(client, info, 0); 267 if (ret < 0) 268 return ret; 269 270 return mp2925_identify_vout_scale(client, info, 1); 271 } 272 273 static const struct pmbus_driver_info mp2925_info = { 274 .pages = MP2925_PAGE_NUM, 275 .format[PSC_VOLTAGE_IN] = linear, 276 .format[PSC_CURRENT_IN] = linear, 277 .format[PSC_CURRENT_OUT] = linear, 278 .format[PSC_POWER] = linear, 279 .format[PSC_TEMPERATURE] = linear, 280 .format[PSC_VOLTAGE_OUT] = direct, 281 282 .m[PSC_VOLTAGE_OUT] = 1, 283 .R[PSC_VOLTAGE_OUT] = 3, 284 .b[PSC_VOLTAGE_OUT] = 0, 285 286 .func[0] = MP2925_RAIL1_FUNC, 287 .func[1] = MP2925_RAIL2_FUNC, 288 .read_word_data = mp2925_read_word_data, 289 .read_byte_data = mp2925_read_byte_data, 290 .write_word_data = mp2925_write_word_data, 291 .identify = mp2925_identify, 292 }; 293 294 static int mp2925_probe(struct i2c_client *client) 295 { 296 struct mp2925_data *data; 297 298 data = devm_kzalloc(&client->dev, sizeof(struct mp2925_data), GFP_KERNEL); 299 if (!data) 300 return -ENOMEM; 301 302 memcpy(&data->info, &mp2925_info, sizeof(mp2925_info)); 303 304 return pmbus_do_probe(client, &data->info); 305 } 306 307 static const struct i2c_device_id mp2925_id[] = { 308 {"mp2925"}, 309 {"mp2929"}, 310 {} 311 }; 312 MODULE_DEVICE_TABLE(i2c, mp2925_id); 313 314 static const struct of_device_id __maybe_unused mp2925_of_match[] = { 315 {.compatible = "mps,mp2925"}, 316 {.compatible = "mps,mp2929"}, 317 {} 318 }; 319 MODULE_DEVICE_TABLE(of, mp2925_of_match); 320 321 static struct i2c_driver mp2925_driver = { 322 .driver = { 323 .name = "mp2925", 324 .of_match_table = mp2925_of_match, 325 }, 326 .probe = mp2925_probe, 327 .id_table = mp2925_id, 328 }; 329 330 module_i2c_driver(mp2925_driver); 331 332 MODULE_AUTHOR("Wensheng Wang <wenswang@yeah.net>"); 333 MODULE_DESCRIPTION("PMBus driver for MPS MP2925"); 334 MODULE_LICENSE("GPL"); 335 MODULE_IMPORT_NS("PMBUS"); 336