// SPDX-License-Identifier: GPL-2.0-or-later /* * Driver for MAX20710, MAX20730, MAX20734, and MAX20743 Integrated, * Step-Down Switching Regulators * * Copyright 2019 Google LLC. * Copyright 2020 Maxim Integrated */ #include #include #include #include #include #include #include #include #include #include #include "pmbus.h" enum chips { max20710, max20730, max20734, max20743 }; struct max20730_data { enum chips id; struct pmbus_driver_info info; struct mutex lock; /* Used to protect against parallel writes */ u16 mfr_devset1; }; #define to_max20730_data(x) container_of(x, struct max20730_data, info) #define MAX20730_MFR_DEVSET1 0xd2 /* * Convert discreet value to direct data format. Strictly speaking, all passed * values are constants, so we could do that calculation manually. On the * downside, that would make the driver more difficult to maintain, so lets * use this approach. */ static u16 val_to_direct(int v, enum pmbus_sensor_classes class, const struct pmbus_driver_info *info) { int R = info->R[class] - 3; /* take milli-units into account */ int b = info->b[class] * 1000; long d; d = v * info->m[class] + b; /* * R < 0 is true for all callers, so we don't need to bother * about the R > 0 case. */ while (R < 0) { d = DIV_ROUND_CLOSEST(d, 10); R++; } return (u16)d; } static long direct_to_val(u16 w, enum pmbus_sensor_classes class, const struct pmbus_driver_info *info) { int R = info->R[class] - 3; int b = info->b[class] * 1000; int m = info->m[class]; long d = (s16)w; if (m == 0) return 0; while (R < 0) { d *= 10; R++; } d = (d - b) / m; return d; } static u32 max_current[][5] = { [max20710] = { 6200, 8000, 9700, 11600 }, [max20730] = { 13000, 16600, 20100, 23600 }, [max20734] = { 21000, 27000, 32000, 38000 }, [max20743] = { 18900, 24100, 29200, 34100 }, }; static int max20730_read_word_data(struct i2c_client *client, int page, int phase, int reg) { const struct pmbus_driver_info *info = pmbus_get_driver_info(client); const struct max20730_data *data = to_max20730_data(info); int ret = 0; u32 max_c; switch (reg) { case PMBUS_OT_FAULT_LIMIT: switch ((data->mfr_devset1 >> 11) & 0x3) { case 0x0: ret = val_to_direct(150000, PSC_TEMPERATURE, info); break; case 0x1: ret = val_to_direct(130000, PSC_TEMPERATURE, info); break; default: ret = -ENODATA; break; } break; case PMBUS_IOUT_OC_FAULT_LIMIT: max_c = max_current[data->id][(data->mfr_devset1 >> 5) & 0x3]; ret = val_to_direct(max_c, PSC_CURRENT_OUT, info); break; default: ret = -ENODATA; break; } return ret; } static int max20730_write_word_data(struct i2c_client *client, int page, int reg, u16 word) { struct pmbus_driver_info *info; struct max20730_data *data; u16 devset1; int ret = 0; int idx; info = (struct pmbus_driver_info *)pmbus_get_driver_info(client); data = to_max20730_data(info); mutex_lock(&data->lock); devset1 = data->mfr_devset1; switch (reg) { case PMBUS_OT_FAULT_LIMIT: devset1 &= ~(BIT(11) | BIT(12)); if (direct_to_val(word, PSC_TEMPERATURE, info) < 140000) devset1 |= BIT(11); break; case PMBUS_IOUT_OC_FAULT_LIMIT: devset1 &= ~(BIT(5) | BIT(6)); idx = find_closest(direct_to_val(word, PSC_CURRENT_OUT, info), max_current[data->id], 4); devset1 |= (idx << 5); break; default: ret = -ENODATA; break; } if (!ret && devset1 != data->mfr_devset1) { ret = i2c_smbus_write_word_data(client, MAX20730_MFR_DEVSET1, devset1); if (!ret) { data->mfr_devset1 = devset1; pmbus_clear_cache(client); } } mutex_unlock(&data->lock); return ret; } static const struct pmbus_driver_info max20730_info[] = { [max20710] = { .pages = 1, .read_word_data = max20730_read_word_data, .write_word_data = max20730_write_word_data, /* Source : Maxim AN6140 and AN6042 */ .format[PSC_TEMPERATURE] = direct, .m[PSC_TEMPERATURE] = 21, .b[PSC_TEMPERATURE] = 5887, .R[PSC_TEMPERATURE] = -1, .format[PSC_VOLTAGE_IN] = direct, .m[PSC_VOLTAGE_IN] = 3609, .b[PSC_VOLTAGE_IN] = 0, .R[PSC_VOLTAGE_IN] = -2, .format[PSC_CURRENT_OUT] = direct, .m[PSC_CURRENT_OUT] = 153, .b[PSC_CURRENT_OUT] = 4976, .R[PSC_CURRENT_OUT] = -1, .format[PSC_VOLTAGE_OUT] = linear, .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_STATUS_INPUT, }, [max20730] = { .pages = 1, .read_word_data = max20730_read_word_data, .write_word_data = max20730_write_word_data, /* Source : Maxim AN6042 */ .format[PSC_TEMPERATURE] = direct, .m[PSC_TEMPERATURE] = 21, .b[PSC_TEMPERATURE] = 5887, .R[PSC_TEMPERATURE] = -1, .format[PSC_VOLTAGE_IN] = direct, .m[PSC_VOLTAGE_IN] = 3609, .b[PSC_VOLTAGE_IN] = 0, .R[PSC_VOLTAGE_IN] = -2, /* * Values in the datasheet are adjusted for temperature and * for the relationship between Vin and Vout. * Unfortunately, the data sheet suggests that Vout measurement * may be scaled with a resistor array. This is indeed the case * at least on the evaulation boards. As a result, any in-driver * adjustments would either be wrong or require elaborate means * to configure the scaling. Instead of doing that, just report * raw values and let userspace handle adjustments. */ .format[PSC_CURRENT_OUT] = direct, .m[PSC_CURRENT_OUT] = 153, .b[PSC_CURRENT_OUT] = 4976, .R[PSC_CURRENT_OUT] = -1, .format[PSC_VOLTAGE_OUT] = linear, .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_STATUS_INPUT, }, [max20734] = { .pages = 1, .read_word_data = max20730_read_word_data, .write_word_data = max20730_write_word_data, /* Source : Maxim AN6209 */ .format[PSC_TEMPERATURE] = direct, .m[PSC_TEMPERATURE] = 21, .b[PSC_TEMPERATURE] = 5887, .R[PSC_TEMPERATURE] = -1, .format[PSC_VOLTAGE_IN] = direct, .m[PSC_VOLTAGE_IN] = 3592, .b[PSC_VOLTAGE_IN] = 0, .R[PSC_VOLTAGE_IN] = -2, .format[PSC_CURRENT_OUT] = direct, .m[PSC_CURRENT_OUT] = 111, .b[PSC_CURRENT_OUT] = 3461, .R[PSC_CURRENT_OUT] = -1, .format[PSC_VOLTAGE_OUT] = linear, .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_STATUS_INPUT, }, [max20743] = { .pages = 1, .read_word_data = max20730_read_word_data, .write_word_data = max20730_write_word_data, /* Source : Maxim AN6042 */ .format[PSC_TEMPERATURE] = direct, .m[PSC_TEMPERATURE] = 21, .b[PSC_TEMPERATURE] = 5887, .R[PSC_TEMPERATURE] = -1, .format[PSC_VOLTAGE_IN] = direct, .m[PSC_VOLTAGE_IN] = 3597, .b[PSC_VOLTAGE_IN] = 0, .R[PSC_VOLTAGE_IN] = -2, .format[PSC_CURRENT_OUT] = direct, .m[PSC_CURRENT_OUT] = 95, .b[PSC_CURRENT_OUT] = 5014, .R[PSC_CURRENT_OUT] = -1, .format[PSC_VOLTAGE_OUT] = linear, .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_STATUS_INPUT, }, }; static int max20730_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct device *dev = &client->dev; u8 buf[I2C_SMBUS_BLOCK_MAX + 1]; struct max20730_data *data; enum chips chip_id; int ret; if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA | I2C_FUNC_SMBUS_READ_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_DATA)) return -ENODEV; ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf); if (ret < 0) { dev_err(&client->dev, "Failed to read Manufacturer ID\n"); return ret; } if (ret != 5 || strncmp(buf, "MAXIM", 5)) { buf[ret] = '\0'; dev_err(dev, "Unsupported Manufacturer ID '%s'\n", buf); return -ENODEV; } /* * The chips support reading PMBUS_MFR_MODEL. On both MAX20730 * and MAX20734, reading it returns M20743. Presumably that is * the reason why the command is not documented. Unfortunately, * that means that there is no reliable means to detect the chip. * However, we can at least detect the chip series. Compare * the returned value against 'M20743' and bail out if there is * a mismatch. If that doesn't work for all chips, we may have * to remove this check. */ ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf); if (ret < 0) { dev_err(dev, "Failed to read Manufacturer Model\n"); return ret; } if (ret != 6 || strncmp(buf, "M20743", 6)) { buf[ret] = '\0'; dev_err(dev, "Unsupported Manufacturer Model '%s'\n", buf); return -ENODEV; } ret = i2c_smbus_read_block_data(client, PMBUS_MFR_REVISION, buf); if (ret < 0) { dev_err(dev, "Failed to read Manufacturer Revision\n"); return ret; } if (ret != 1 || buf[0] != 'F') { buf[ret] = '\0'; dev_err(dev, "Unsupported Manufacturer Revision '%s'\n", buf); return -ENODEV; } if (client->dev.of_node) chip_id = (enum chips)of_device_get_match_data(dev); else chip_id = id->driver_data; data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; data->id = chip_id; mutex_init(&data->lock); memcpy(&data->info, &max20730_info[chip_id], sizeof(data->info)); ret = i2c_smbus_read_word_data(client, MAX20730_MFR_DEVSET1); if (ret < 0) return ret; data->mfr_devset1 = ret; return pmbus_do_probe(client, id, &data->info); } static const struct i2c_device_id max20730_id[] = { { "max20710", max20710 }, { "max20730", max20730 }, { "max20734", max20734 }, { "max20743", max20743 }, { }, }; MODULE_DEVICE_TABLE(i2c, max20730_id); static const struct of_device_id max20730_of_match[] = { { .compatible = "maxim,max20710", .data = (void *)max20710 }, { .compatible = "maxim,max20730", .data = (void *)max20730 }, { .compatible = "maxim,max20734", .data = (void *)max20734 }, { .compatible = "maxim,max20743", .data = (void *)max20743 }, { }, }; MODULE_DEVICE_TABLE(of, max20730_of_match); static struct i2c_driver max20730_driver = { .driver = { .name = "max20730", .of_match_table = max20730_of_match, }, .probe = max20730_probe, .remove = pmbus_do_remove, .id_table = max20730_id, }; module_i2c_driver(max20730_driver); MODULE_AUTHOR("Guenter Roeck "); MODULE_DESCRIPTION("PMBus driver for Maxim MAX20710 / MAX20730 / MAX20734 / MAX20743"); MODULE_LICENSE("GPL");