1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Hardware monitoring driver for PMBus devices 4 * 5 * Copyright (c) 2010, 2011 Ericsson AB. 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/module.h> 10 #include <linux/init.h> 11 #include <linux/err.h> 12 #include <linux/slab.h> 13 #include <linux/mutex.h> 14 #include <linux/i2c.h> 15 #include <linux/pmbus.h> 16 #include "pmbus.h" 17 18 struct pmbus_device_info { 19 int pages; 20 u32 flags; 21 }; 22 23 static const struct i2c_device_id pmbus_id[]; 24 25 /* 26 * Find sensor groups and status registers on each page. 27 */ 28 static void pmbus_find_sensor_groups(struct i2c_client *client, 29 struct pmbus_driver_info *info) 30 { 31 int page; 32 33 /* Sensors detected on page 0 only */ 34 if (pmbus_check_word_register(client, 0, PMBUS_READ_VIN)) 35 info->func[0] |= PMBUS_HAVE_VIN; 36 if (pmbus_check_word_register(client, 0, PMBUS_READ_VCAP)) 37 info->func[0] |= PMBUS_HAVE_VCAP; 38 if (pmbus_check_word_register(client, 0, PMBUS_READ_IIN)) 39 info->func[0] |= PMBUS_HAVE_IIN; 40 if (pmbus_check_word_register(client, 0, PMBUS_READ_PIN)) 41 info->func[0] |= PMBUS_HAVE_PIN; 42 if (info->func[0] 43 && pmbus_check_byte_register(client, 0, PMBUS_STATUS_INPUT)) 44 info->func[0] |= PMBUS_HAVE_STATUS_INPUT; 45 if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_12) && 46 pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_1)) { 47 info->func[0] |= PMBUS_HAVE_FAN12; 48 if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_12)) 49 info->func[0] |= PMBUS_HAVE_STATUS_FAN12; 50 } 51 if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_34) && 52 pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_3)) { 53 info->func[0] |= PMBUS_HAVE_FAN34; 54 if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_34)) 55 info->func[0] |= PMBUS_HAVE_STATUS_FAN34; 56 } 57 if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_1)) 58 info->func[0] |= PMBUS_HAVE_TEMP; 59 if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_2)) 60 info->func[0] |= PMBUS_HAVE_TEMP2; 61 if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_3)) 62 info->func[0] |= PMBUS_HAVE_TEMP3; 63 if (info->func[0] & (PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 64 | PMBUS_HAVE_TEMP3) 65 && pmbus_check_byte_register(client, 0, 66 PMBUS_STATUS_TEMPERATURE)) 67 info->func[0] |= PMBUS_HAVE_STATUS_TEMP; 68 69 /* Sensors detected on all pages */ 70 for (page = 0; page < info->pages; page++) { 71 if (pmbus_check_word_register(client, page, PMBUS_READ_VOUT)) { 72 info->func[page] |= PMBUS_HAVE_VOUT; 73 if (pmbus_check_byte_register(client, page, 74 PMBUS_STATUS_VOUT)) 75 info->func[page] |= PMBUS_HAVE_STATUS_VOUT; 76 } 77 if (pmbus_check_word_register(client, page, PMBUS_READ_IOUT)) { 78 info->func[page] |= PMBUS_HAVE_IOUT; 79 if (pmbus_check_byte_register(client, 0, 80 PMBUS_STATUS_IOUT)) 81 info->func[page] |= PMBUS_HAVE_STATUS_IOUT; 82 } 83 if (pmbus_check_word_register(client, page, PMBUS_READ_POUT)) 84 info->func[page] |= PMBUS_HAVE_POUT; 85 } 86 } 87 88 /* 89 * Identify chip parameters. 90 */ 91 static int pmbus_identify(struct i2c_client *client, 92 struct pmbus_driver_info *info) 93 { 94 int ret = 0; 95 96 if (!info->pages) { 97 /* 98 * Check if the PAGE command is supported. If it is, 99 * keep setting the page number until it fails or until the 100 * maximum number of pages has been reached. Assume that 101 * this is the number of pages supported by the chip. 102 */ 103 if (pmbus_check_byte_register(client, 0, PMBUS_PAGE)) { 104 int page; 105 106 for (page = 1; page < PMBUS_PAGES; page++) { 107 if (pmbus_set_page(client, page, 0xff) < 0) 108 break; 109 } 110 pmbus_set_page(client, 0, 0xff); 111 info->pages = page; 112 } else { 113 info->pages = 1; 114 } 115 116 pmbus_clear_faults(client); 117 } 118 119 if (pmbus_check_byte_register(client, 0, PMBUS_VOUT_MODE)) { 120 int vout_mode, i; 121 122 vout_mode = pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE); 123 if (vout_mode >= 0 && vout_mode != 0xff) { 124 switch (vout_mode >> 5) { 125 case 0: 126 break; 127 case 1: 128 info->format[PSC_VOLTAGE_OUT] = vid; 129 for (i = 0; i < info->pages; i++) 130 info->vrm_version[i] = vr11; 131 break; 132 case 2: 133 info->format[PSC_VOLTAGE_OUT] = direct; 134 break; 135 default: 136 ret = -ENODEV; 137 goto abort; 138 } 139 } 140 } 141 142 /* 143 * We should check if the COEFFICIENTS register is supported. 144 * If it is, and the chip is configured for direct mode, we can read 145 * the coefficients from the chip, one set per group of sensor 146 * registers. 147 * 148 * To do this, we will need access to a chip which actually supports the 149 * COEFFICIENTS command, since the command is too complex to implement 150 * without testing it. Until then, abort if a chip configured for direct 151 * mode was detected. 152 */ 153 if (info->format[PSC_VOLTAGE_OUT] == direct) { 154 ret = -ENODEV; 155 goto abort; 156 } 157 158 /* Try to find sensor groups */ 159 pmbus_find_sensor_groups(client, info); 160 abort: 161 return ret; 162 } 163 164 static int pmbus_probe(struct i2c_client *client) 165 { 166 struct pmbus_driver_info *info; 167 struct pmbus_platform_data *pdata = NULL; 168 struct device *dev = &client->dev; 169 struct pmbus_device_info *device_info; 170 171 info = devm_kzalloc(dev, sizeof(struct pmbus_driver_info), GFP_KERNEL); 172 if (!info) 173 return -ENOMEM; 174 175 device_info = (struct pmbus_device_info *)i2c_match_id(pmbus_id, client)->driver_data; 176 if (device_info->flags & PMBUS_SKIP_STATUS_CHECK) { 177 pdata = devm_kzalloc(dev, sizeof(struct pmbus_platform_data), 178 GFP_KERNEL); 179 if (!pdata) 180 return -ENOMEM; 181 182 pdata->flags = PMBUS_SKIP_STATUS_CHECK; 183 } 184 185 info->pages = device_info->pages; 186 info->identify = pmbus_identify; 187 dev->platform_data = pdata; 188 189 return pmbus_do_probe(client, info); 190 } 191 192 static const struct pmbus_device_info pmbus_info_one = { 193 .pages = 1, 194 .flags = 0 195 }; 196 static const struct pmbus_device_info pmbus_info_zero = { 197 .pages = 0, 198 .flags = 0 199 }; 200 static const struct pmbus_device_info pmbus_info_one_skip = { 201 .pages = 1, 202 .flags = PMBUS_SKIP_STATUS_CHECK 203 }; 204 205 /* 206 * Use driver_data to set the number of pages supported by the chip. 207 */ 208 static const struct i2c_device_id pmbus_id[] = { 209 {"adp4000", (kernel_ulong_t)&pmbus_info_one}, 210 {"bmr453", (kernel_ulong_t)&pmbus_info_one}, 211 {"bmr454", (kernel_ulong_t)&pmbus_info_one}, 212 {"dps460", (kernel_ulong_t)&pmbus_info_one_skip}, 213 {"dps650ab", (kernel_ulong_t)&pmbus_info_one_skip}, 214 {"dps800", (kernel_ulong_t)&pmbus_info_one_skip}, 215 {"max20796", (kernel_ulong_t)&pmbus_info_one}, 216 {"mdt040", (kernel_ulong_t)&pmbus_info_one}, 217 {"ncp4200", (kernel_ulong_t)&pmbus_info_one}, 218 {"ncp4208", (kernel_ulong_t)&pmbus_info_one}, 219 {"pdt003", (kernel_ulong_t)&pmbus_info_one}, 220 {"pdt006", (kernel_ulong_t)&pmbus_info_one}, 221 {"pdt012", (kernel_ulong_t)&pmbus_info_one}, 222 {"pmbus", (kernel_ulong_t)&pmbus_info_zero}, 223 {"sgd009", (kernel_ulong_t)&pmbus_info_one_skip}, 224 {"tps40400", (kernel_ulong_t)&pmbus_info_one}, 225 {"tps544b20", (kernel_ulong_t)&pmbus_info_one}, 226 {"tps544b25", (kernel_ulong_t)&pmbus_info_one}, 227 {"tps544c20", (kernel_ulong_t)&pmbus_info_one}, 228 {"tps544c25", (kernel_ulong_t)&pmbus_info_one}, 229 {"udt020", (kernel_ulong_t)&pmbus_info_one}, 230 {} 231 }; 232 233 MODULE_DEVICE_TABLE(i2c, pmbus_id); 234 235 /* This is the driver that will be inserted */ 236 static struct i2c_driver pmbus_driver = { 237 .driver = { 238 .name = "pmbus", 239 }, 240 .probe_new = pmbus_probe, 241 .id_table = pmbus_id, 242 }; 243 244 module_i2c_driver(pmbus_driver); 245 246 MODULE_AUTHOR("Guenter Roeck"); 247 MODULE_DESCRIPTION("Generic PMBus driver"); 248 MODULE_LICENSE("GPL"); 249 MODULE_IMPORT_NS(PMBUS); 250