diff options
Diffstat (limited to 'drivers/hwmon/pmbus/zl6100.c')
| -rw-r--r-- | drivers/hwmon/pmbus/zl6100.c | 419 |
1 files changed, 419 insertions, 0 deletions
diff --git a/drivers/hwmon/pmbus/zl6100.c b/drivers/hwmon/pmbus/zl6100.c new file mode 100644 index 0000000..8196441 --- /dev/null +++ b/drivers/hwmon/pmbus/zl6100.c @@ -0,0 +1,419 @@ +/* + * Hardware monitoring driver for ZL6100 and compatibles + * + * Copyright (c) 2011 Ericsson AB. + * Copyright (c) 2012 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 <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 (1 << 7) + +#define MFR_VMON_OV_FAULT_LIMIT 0xf5 +#define MFR_VMON_UV_FAULT_LIMIT 0xf6 +#define MFR_READ_VMON 0xf7 + +#define VMON_UV_WARNING (1 << 5) +#define VMON_OV_WARNING (1 << 4) +#define VMON_UV_FAULT (1 << 1) +#define VMON_OV_FAULT (1 << 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"); |
