| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * Hardware monitoring driver for ZL6100 and compatibles |
| * |
| * Copyright (c) 2011 Ericsson AB. |
| * Copyright (c) 2012 Guenter Roeck |
| */ |
| |
| #include <linux/bitops.h> |
| #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 <linux/ktime.h> |
| #include <linux/delay.h> |
| #include "pmbus.h" |
| |
| enum chips { zl2004, zl2005, zl2006, zl2008, zl2105, zl2106, zl6100, zl6105, |
| zl9101, zl9117 }; |
| |
| struct zl6100_data { |
| int id; |
| ktime_t access; /* chip access time */ |
| int delay; /* Delay between chip accesses in uS */ |
| struct pmbus_driver_info info; |
| }; |
| |
| #define to_zl6100_data(x) container_of(x, struct zl6100_data, info) |
| |
| #define ZL6100_MFR_CONFIG 0xd0 |
| #define ZL6100_DEVICE_ID 0xe4 |
| |
| #define ZL6100_MFR_XTEMP_ENABLE BIT(7) |
| |
| #define MFR_VMON_OV_FAULT_LIMIT 0xf5 |
| #define MFR_VMON_UV_FAULT_LIMIT 0xf6 |
| #define MFR_READ_VMON 0xf7 |
| |
| #define VMON_UV_WARNING BIT(5) |
| #define VMON_OV_WARNING BIT(4) |
| #define VMON_UV_FAULT BIT(1) |
| #define VMON_OV_FAULT BIT(0) |
| |
| #define ZL6100_WAIT_TIME 1000 /* uS */ |
| |
| static ushort delay = ZL6100_WAIT_TIME; |
| module_param(delay, ushort, 0644); |
| MODULE_PARM_DESC(delay, "Delay between chip accesses in uS"); |
| |
| /* Convert linear sensor value to milli-units */ |
| static long zl6100_l2d(s16 l) |
| { |
| s16 exponent; |
| s32 mantissa; |
| long val; |
| |
| exponent = l >> 11; |
| mantissa = ((s16)((l & 0x7ff) << 5)) >> 5; |
| |
| val = mantissa; |
| |
| /* scale result to milli-units */ |
| val = val * 1000L; |
| |
| if (exponent >= 0) |
| val <<= exponent; |
| else |
| val >>= -exponent; |
| |
| return val; |
| } |
| |
| #define MAX_MANTISSA (1023 * 1000) |
| #define MIN_MANTISSA (511 * 1000) |
| |
| static u16 zl6100_d2l(long val) |
| { |
| s16 exponent = 0, mantissa; |
| bool negative = false; |
| |
| /* simple case */ |
| if (val == 0) |
| return 0; |
| |
| if (val < 0) { |
| negative = true; |
| val = -val; |
| } |
| |
| /* Reduce large mantissa until it fits into 10 bit */ |
| while (val >= MAX_MANTISSA && exponent < 15) { |
| exponent++; |
| val >>= 1; |
| } |
| /* Increase small mantissa to improve precision */ |
| while (val < MIN_MANTISSA && exponent > -15) { |
| exponent--; |
| val <<= 1; |
| } |
| |
| /* Convert mantissa from milli-units to units */ |
| mantissa = DIV_ROUND_CLOSEST(val, 1000); |
| |
| /* Ensure that resulting number is within range */ |
| if (mantissa > 0x3ff) |
| mantissa = 0x3ff; |
| |
| /* restore sign */ |
| if (negative) |
| mantissa = -mantissa; |
| |
| /* Convert to 5 bit exponent, 11 bit mantissa */ |
| return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800); |
| } |
| |
| /* Some chips need a delay between accesses */ |
| static inline void zl6100_wait(const struct zl6100_data *data) |
| { |
| if (data->delay) { |
| s64 delta = ktime_us_delta(ktime_get(), data->access); |
| if (delta < data->delay) |
| udelay(data->delay - delta); |
| } |
| } |
| |
| static int zl6100_read_word_data(struct i2c_client *client, int page, int reg) |
| { |
| const struct pmbus_driver_info *info = pmbus_get_driver_info(client); |
| struct zl6100_data *data = to_zl6100_data(info); |
| int ret, vreg; |
| |
| if (page > 0) |
| return -ENXIO; |
| |
| if (data->id == zl2005) { |
| /* |
| * Limit register detection is not reliable on ZL2005. |
| * Make sure registers are not erroneously detected. |
| */ |
| switch (reg) { |
| case PMBUS_VOUT_OV_WARN_LIMIT: |
| case PMBUS_VOUT_UV_WARN_LIMIT: |
| case PMBUS_IOUT_OC_WARN_LIMIT: |
| return -ENXIO; |
| } |
| } |
| |
| switch (reg) { |
| case PMBUS_VIRT_READ_VMON: |
| vreg = MFR_READ_VMON; |
| break; |
| case PMBUS_VIRT_VMON_OV_WARN_LIMIT: |
| case PMBUS_VIRT_VMON_OV_FAULT_LIMIT: |
| vreg = MFR_VMON_OV_FAULT_LIMIT; |
| break; |
| case PMBUS_VIRT_VMON_UV_WARN_LIMIT: |
| case PMBUS_VIRT_VMON_UV_FAULT_LIMIT: |
| vreg = MFR_VMON_UV_FAULT_LIMIT; |
| break; |
| default: |
| if (reg >= PMBUS_VIRT_BASE) |
| return -ENXIO; |
| vreg = reg; |
| break; |
| } |
| |
| zl6100_wait(data); |
| ret = pmbus_read_word_data(client, page, vreg); |
| data->access = ktime_get(); |
| if (ret < 0) |
| return ret; |
| |
| switch (reg) { |
| case PMBUS_VIRT_VMON_OV_WARN_LIMIT: |
| ret = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(ret) * 9, 10)); |
| break; |
| case PMBUS_VIRT_VMON_UV_WARN_LIMIT: |
| ret = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(ret) * 11, 10)); |
| break; |
| } |
| |
| return ret; |
| } |
| |
| static int zl6100_read_byte_data(struct i2c_client *client, int page, int reg) |
| { |
| const struct pmbus_driver_info *info = pmbus_get_driver_info(client); |
| struct zl6100_data *data = to_zl6100_data(info); |
| int ret, status; |
| |
| if (page > 0) |
| return -ENXIO; |
| |
| zl6100_wait(data); |
| |
| switch (reg) { |
| case PMBUS_VIRT_STATUS_VMON: |
| ret = pmbus_read_byte_data(client, 0, |
| PMBUS_STATUS_MFR_SPECIFIC); |
| if (ret < 0) |
| break; |
| |
| status = 0; |
| if (ret & VMON_UV_WARNING) |
| status |= PB_VOLTAGE_UV_WARNING; |
| if (ret & VMON_OV_WARNING) |
| status |= PB_VOLTAGE_OV_WARNING; |
| if (ret & VMON_UV_FAULT) |
| status |= PB_VOLTAGE_UV_FAULT; |
| if (ret & VMON_OV_FAULT) |
| status |= PB_VOLTAGE_OV_FAULT; |
| ret = status; |
| break; |
| default: |
| ret = pmbus_read_byte_data(client, page, reg); |
| break; |
| } |
| data->access = ktime_get(); |
| |
| return ret; |
| } |
| |
| static int zl6100_write_word_data(struct i2c_client *client, int page, int reg, |
| u16 word) |
| { |
| const struct pmbus_driver_info *info = pmbus_get_driver_info(client); |
| struct zl6100_data *data = to_zl6100_data(info); |
| int ret, vreg; |
| |
| if (page > 0) |
| return -ENXIO; |
| |
| switch (reg) { |
| case PMBUS_VIRT_VMON_OV_WARN_LIMIT: |
| word = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(word) * 10, 9)); |
| vreg = MFR_VMON_OV_FAULT_LIMIT; |
| pmbus_clear_cache(client); |
| break; |
| case PMBUS_VIRT_VMON_OV_FAULT_LIMIT: |
| vreg = MFR_VMON_OV_FAULT_LIMIT; |
| pmbus_clear_cache(client); |
| break; |
| case PMBUS_VIRT_VMON_UV_WARN_LIMIT: |
| word = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(word) * 10, 11)); |
| vreg = MFR_VMON_UV_FAULT_LIMIT; |
| pmbus_clear_cache(client); |
| break; |
| case PMBUS_VIRT_VMON_UV_FAULT_LIMIT: |
| vreg = MFR_VMON_UV_FAULT_LIMIT; |
| pmbus_clear_cache(client); |
| break; |
| default: |
| if (reg >= PMBUS_VIRT_BASE) |
| return -ENXIO; |
| vreg = reg; |
| } |
| |
| zl6100_wait(data); |
| ret = pmbus_write_word_data(client, page, vreg, word); |
| data->access = ktime_get(); |
| |
| return ret; |
| } |
| |
| static int zl6100_write_byte(struct i2c_client *client, int page, u8 value) |
| { |
| const struct pmbus_driver_info *info = pmbus_get_driver_info(client); |
| struct zl6100_data *data = to_zl6100_data(info); |
| int ret; |
| |
| if (page > 0) |
| return -ENXIO; |
| |
| zl6100_wait(data); |
| ret = pmbus_write_byte(client, page, value); |
| data->access = ktime_get(); |
| |
| return ret; |
| } |
| |
| static const struct i2c_device_id zl6100_id[] = { |
| {"bmr450", zl2005}, |
| {"bmr451", zl2005}, |
| {"bmr462", zl2008}, |
| {"bmr463", zl2008}, |
| {"bmr464", zl2008}, |
| {"zl2004", zl2004}, |
| {"zl2005", zl2005}, |
| {"zl2006", zl2006}, |
| {"zl2008", zl2008}, |
| {"zl2105", zl2105}, |
| {"zl2106", zl2106}, |
| {"zl6100", zl6100}, |
| {"zl6105", zl6105}, |
| {"zl9101", zl9101}, |
| {"zl9117", zl9117}, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, zl6100_id); |
| |
| static int zl6100_probe(struct i2c_client *client, |
| const struct i2c_device_id *id) |
| { |
| int ret; |
| struct zl6100_data *data; |
| struct pmbus_driver_info *info; |
| u8 device_id[I2C_SMBUS_BLOCK_MAX + 1]; |
| const struct i2c_device_id *mid; |
| |
| if (!i2c_check_functionality(client->adapter, |
| I2C_FUNC_SMBUS_READ_WORD_DATA |
| | I2C_FUNC_SMBUS_READ_BLOCK_DATA)) |
| return -ENODEV; |
| |
| ret = i2c_smbus_read_block_data(client, ZL6100_DEVICE_ID, |
| device_id); |
| if (ret < 0) { |
| dev_err(&client->dev, "Failed to read device ID\n"); |
| return ret; |
| } |
| device_id[ret] = '\0'; |
| dev_info(&client->dev, "Device ID %s\n", device_id); |
| |
| mid = NULL; |
| for (mid = zl6100_id; mid->name[0]; mid++) { |
| if (!strncasecmp(mid->name, device_id, strlen(mid->name))) |
| break; |
| } |
| if (!mid->name[0]) { |
| dev_err(&client->dev, "Unsupported device\n"); |
| return -ENODEV; |
| } |
| if (id->driver_data != mid->driver_data) |
| dev_notice(&client->dev, |
| "Device mismatch: Configured %s, detected %s\n", |
| id->name, mid->name); |
| |
| data = devm_kzalloc(&client->dev, sizeof(struct zl6100_data), |
| GFP_KERNEL); |
| if (!data) |
| return -ENOMEM; |
| |
| data->id = mid->driver_data; |
| |
| /* |
| * According to information from the chip vendor, all currently |
| * supported chips are known to require a wait time between I2C |
| * accesses. |
| */ |
| data->delay = delay; |
| |
| /* |
| * Since there was a direct I2C device access above, wait before |
| * accessing the chip again. |
| */ |
| data->access = ktime_get(); |
| zl6100_wait(data); |
| |
| info = &data->info; |
| |
| info->pages = 1; |
| info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT |
| | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
| | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
| | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP; |
| |
| /* |
| * ZL2004, ZL9101M, and ZL9117M support monitoring an extra voltage |
| * (VMON for ZL2004, VDRV for ZL9101M and ZL9117M). Report it as vmon. |
| */ |
| if (data->id == zl2004 || data->id == zl9101 || data->id == zl9117) |
| info->func[0] |= PMBUS_HAVE_VMON | PMBUS_HAVE_STATUS_VMON; |
| |
| ret = i2c_smbus_read_word_data(client, ZL6100_MFR_CONFIG); |
| if (ret < 0) |
| return ret; |
| |
| if (ret & ZL6100_MFR_XTEMP_ENABLE) |
| info->func[0] |= PMBUS_HAVE_TEMP2; |
| |
| data->access = ktime_get(); |
| zl6100_wait(data); |
| |
| info->read_word_data = zl6100_read_word_data; |
| info->read_byte_data = zl6100_read_byte_data; |
| info->write_word_data = zl6100_write_word_data; |
| info->write_byte = zl6100_write_byte; |
| |
| return pmbus_do_probe(client, mid, info); |
| } |
| |
| static struct i2c_driver zl6100_driver = { |
| .driver = { |
| .name = "zl6100", |
| }, |
| .probe = zl6100_probe, |
| .remove = pmbus_do_remove, |
| .id_table = zl6100_id, |
| }; |
| |
| module_i2c_driver(zl6100_driver); |
| |
| MODULE_AUTHOR("Guenter Roeck"); |
| MODULE_DESCRIPTION("PMBus driver for ZL6100 and compatibles"); |
| MODULE_LICENSE("GPL"); |