ltc2978.rar_ltc2978_ltc3880

/* * Hardware monitoring driver for LTC2974, LTC2977, LTC2978, LTC3880, * and LTC3883 * * Copyright (c) 2011 Ericsson AB. * Copyright (c) 2013 Guenter Roeck * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/err.h> #include <linux/slab.h> #include <linux/i2c.h> #include "pmbus.h" enum chips { ltc2974, ltc2977, ltc2978, ltc3880, ltc3883 }; /* Common for all chips */ #define LTC2978_MFR_VOUT_PEAK 0xdd #define LTC2978_MFR_VIN_PEAK 0xde #define LTC2978_MFR_TEMPERATURE_PEAK 0xdf #define LTC2978_MFR_SPECIAL_ID 0xe7 /* LTC2974, LCT2977, and LTC2978 */ #define LTC2978_MFR_VOUT_MIN 0xfb #define LTC2978_MFR_VIN_MIN 0xfc #define LTC2978_MFR_TEMPERATURE_MIN 0xfd /* LTC2974 only */ #define LTC2974_MFR_IOUT_PEAK 0xd7 #define LTC2974_MFR_IOUT_MIN 0xd8 /* LTC3880 and LTC3883 */ #define LTC3880_MFR_IOUT_PEAK 0xd7 #define LTC3880_MFR_CLEAR_PEAKS 0xe3 #define LTC3880_MFR_TEMPERATURE2_PEAK 0xf4 /* LTC3883 only */ #define LTC3883_MFR_IIN_PEAK 0xe1 #define LTC2974_ID 0x0212 #define LTC2977_ID 0x0130 #define LTC2978_ID_REV1 0x0121 #define LTC2978_ID_REV2 0x0122 #define LTC2978A_ID 0x0124 #define LTC3880_ID 0x4000 #define LTC3880_ID_MASK 0xff00 #define LTC3883_ID 0x4300 #define LTC3883_ID_MASK 0xff00 #define LTC2974_NUM_PAGES 4 #define LTC2978_NUM_PAGES 8 #define LTC3880_NUM_PAGES 2 #define LTC3883_NUM_PAGES 1 /* * LTC2978 clears peak data whenever the CLEAR_FAULTS command is executed, which * happens pretty much each time chip data is updated. Raw peak data therefore * does not provide much value. To be able to provide useful peak data, keep an * internal cache of measured peak data, which is only cleared if an explicit * "clear peak" command is executed for the sensor in question. */ struct ltc2978_data { enum chips id; u16 vin_min, vin_max; u16 temp_min[LTC2974_NUM_PAGES], temp_max[LTC2974_NUM_PAGES]; u16 vout_min[LTC2978_NUM_PAGES], vout_max[LTC2978_NUM_PAGES]; u16 iout_min[LTC2974_NUM_PAGES], iout_max[LTC2974_NUM_PAGES]; u16 iin_max; u16 temp2_max; struct pmbus_driver_info info; }; #define to_ltc2978_data(x) container_of(x, struct ltc2978_data, info) static inline int lin11_to_val(int data) { s16 e = ((s16)data) >> 11; s32 m = (((s16)(data << 5)) >> 5); /* * mantissa is 10 bit + sign, exponent adds up to 15 bit. * Add 6 bit to exponent for maximum accuracy (10 + 15 + 6 = 31). */ e += 6; return (e < 0 ? m >> -e : m << e); } static int ltc2978_read_word_data_common(struct i2c_client *client, int page, int reg) { const struct pmbus_driver_info *info = pmbus_get_driver_info(client); struct ltc2978_data *data = to_ltc2978_data(info); int ret; switch (reg) { case PMBUS_VIRT_READ_VIN_MAX: ret = pmbus_read_word_data(client, page, LTC2978_MFR_VIN_PEAK); if (ret >= 0) { if (lin11_to_val(ret) > lin11_to_val(data->vin_max)) data->vin_max = ret; ret = data->vin_max; } break; case PMBUS_VIRT_READ_VOUT_MAX: ret = pmbus_read_word_data(client, page, LTC2978_MFR_VOUT_PEAK); if (ret >= 0) { /* * VOUT is 16 bit unsigned with fixed exponent, * so we can compare it directly */ if (ret > data->vout_max[page]) data->vout_max[page] = ret; ret = data->vout_max[page]; } break; case PMBUS_VIRT_READ_TEMP_MAX: ret = pmbus_read_word_data(client, page, LTC2978_MFR_TEMPERATURE_PEAK); if (ret >= 0) { if (lin11_to_val(ret) > lin11_to_val(data->temp_max[page])) data->temp_max[page] = ret; ret = data->temp_max[page]; } break; case PMBUS_VIRT_RESET_VOUT_HISTORY: case PMBUS_VIRT_RESET_VIN_HISTORY: case PMBUS_VIRT_RESET_TEMP_HISTORY: ret = 0; break; default: ret = -ENODATA; break; } return ret; } static int ltc2978_read_word_data(struct i2c_client *client, int page, int reg) { const struct pmbus_driver_info *info = pmbus_get_driver_info(client); struct ltc2978_data *data = to_ltc2978_data(info); int ret; switch (reg) { case PMBUS_VIRT_READ_VIN_MIN: ret = pmbus_read_word_data(client, page, LTC2978_MFR_VIN_MIN); if (ret >= 0) { if (lin11_to_val(ret) < lin11_to_val(data->vin_min)) data->vin_min = ret; ret = data->vin_min; } break; case PMBUS_VIRT_READ_VOUT_MIN: ret = pmbus_read_word_data(client, page, LTC2978_MFR_VOUT_MIN); if (ret >= 0) { /* * VOUT_MIN is known to not be supported on some lots * of LTC2978 revision 1, and will return the maximum * possible voltage if read. If VOUT_MAX is valid and * lower than the reading of VOUT_MIN, use it instead. */ if (data->vout_max[page] && ret > data->vout_max[page]) ret = data->vout_max[page]; if (ret < data->vout_min[page]) data->vout_min[page] = ret; ret = data->vout_min[page]; } break; case PMBUS_VIRT_READ_TEMP_MIN: ret = pmbus_read_word_data(client, page, LTC2978_MFR_TEMPERATURE_MIN); if (ret >= 0) { if (lin11_to_val(ret) < lin11_to_val(data->temp_min[page])) data->temp_min[page] = ret; ret = data->temp_min[page]; } break; case PMBUS_VIRT_READ_IOUT_MAX: case PMBUS_VIRT_RESET_IOUT_HISTORY: case PMBUS_VIRT_READ_TEMP2_MAX: case PMBUS_VIRT_RESET_TEMP2_HISTORY: ret = -ENXIO; break; default: ret = ltc2978_read_word_data_common(client, page, reg); break; } return ret; } static int ltc2974_read_word_data(struct i2c_client *client, int page, int reg) { const struct pmbus_driver_info *info = pmbus_get_driver_info(client); struct ltc2978_data *data = to_ltc2978_data(info); int ret; switch (reg) { case PMBUS_VIRT_READ_IOUT_MAX: ret = pmbus_read_word_data(client, page, LTC2974_MFR_IOUT_PEAK); if (ret >= 0) { if (lin11_to_val(ret) > lin11_to_val(data->iout_max[page])) data->iout_max[page] = ret; ret = data->iout_max[page]; } break; case PMBUS_VIRT_READ_IOUT_MIN: ret = pmbus_read_word_data(client, page, LTC2974_MFR_IOUT_MIN); if (ret >= 0) { if (lin11_to_val(ret) < lin11_to_val(data->iout_min[page])) data->iout_min[page] = ret; ret = data->iout_min[page]; } break; case PMBUS_VIRT_RESET_IOUT_HISTORY: ret = 0; break; default: ret = ltc2978_read_word_data(client, page, reg); break; } return ret; } static int ltc3880_read_word_data(struct i2c_client *client, int page, int reg) { const struct pmbus_driver_info *info = pmbus_get_driver_info(client); struct ltc2978_data *data = to_ltc2978_data(info); int ret; switch (reg) { case PMBUS_VIRT_READ_IOUT_MAX: ret = pmbus_read_word_data(client, page, LTC3880_MFR_IOUT_PEAK); if (ret >= 0) { if (lin11_to_val(ret) > lin11_to_val(data->iout_max[page])) data->iout_max[page] = ret; ret = data->iout_max[page]; } break; case PMBUS_VIRT_READ_TEMP2_MAX: ret = pmbus_read_word_data(client, page, LTC3880_MFR_TEMPERATURE2_PEAK); if (ret >= 0) { if (lin11_to_val(ret) > lin11_to_val(data->temp2_max)) data->temp2_max = ret; ret = data->temp2_max; } break; case PMBUS_VIRT_READ_VIN_MIN: case PMBUS_VIRT_READ_VOUT_MIN: case PMBUS_VIRT_READ_TEMP_MIN: ret = -ENXIO; break; case PMBUS_VIRT_RESET_IOUT_HISTORY: case PMBUS_VIRT_RESET_TEMP2_HISTORY: ret = 0; break; default: ret = ltc2978_read_word_data_common(client, page, reg); break; } return ret; } static int ltc3883_read_word_data(