From daa436e67cd2dcac7cbb505bb4425fdfdafaa5a7 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Thu, 30 Jan 2014 19:51:14 -0800 Subject: [PATCH] hwmon: (pmbus) Support per-page exponent in linear mode Some chips use different exponents for sensors on different pages or rails. Detect and store exponent per page to support this situation. This fixes a problem with wrong voltages seen on UCD90120. Reported-by: Soren Brinkmann Tested-by: Soren Brinkmann Signed-off-by: Guenter Roeck --- drivers/hwmon/pmbus/pmbus_core.c | 68 +++++++++++++++++--------------- 1 file changed, 36 insertions(+), 32 deletions(-) diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c index 3cbf66e9d86..291d11fe93e 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -90,7 +90,8 @@ struct pmbus_data { u32 flags; /* from platform data */ - int exponent; /* linear mode: exponent for output voltages */ + int exponent[PMBUS_PAGES]; + /* linear mode: exponent for output voltages */ const struct pmbus_driver_info *info; @@ -410,7 +411,7 @@ static long pmbus_reg2data_linear(struct pmbus_data *data, long val; if (sensor->class == PSC_VOLTAGE_OUT) { /* LINEAR16 */ - exponent = data->exponent; + exponent = data->exponent[sensor->page]; mantissa = (u16) sensor->data; } else { /* LINEAR11 */ exponent = ((s16)sensor->data) >> 11; @@ -516,7 +517,7 @@ static long pmbus_reg2data(struct pmbus_data *data, struct pmbus_sensor *sensor) #define MIN_MANTISSA (511 * 1000) static u16 pmbus_data2reg_linear(struct pmbus_data *data, - enum pmbus_sensor_classes class, long val) + struct pmbus_sensor *sensor, long val) { s16 exponent = 0, mantissa; bool negative = false; @@ -525,7 +526,7 @@ static u16 pmbus_data2reg_linear(struct pmbus_data *data, if (val == 0) return 0; - if (class == PSC_VOLTAGE_OUT) { + if (sensor->class == PSC_VOLTAGE_OUT) { /* LINEAR16 does not support negative voltages */ if (val < 0) return 0; @@ -534,10 +535,10 @@ static u16 pmbus_data2reg_linear(struct pmbus_data *data, * For a static exponents, we don't have a choice * but to adjust the value to it. */ - if (data->exponent < 0) - val <<= -data->exponent; + if (data->exponent[sensor->page] < 0) + val <<= -data->exponent[sensor->page]; else - val >>= data->exponent; + val >>= data->exponent[sensor->page]; val = DIV_ROUND_CLOSEST(val, 1000); return val & 0xffff; } @@ -548,14 +549,14 @@ static u16 pmbus_data2reg_linear(struct pmbus_data *data, } /* Power is in uW. Convert to mW before converting. */ - if (class == PSC_POWER) + if (sensor->class == PSC_POWER) val = DIV_ROUND_CLOSEST(val, 1000L); /* * For simplicity, convert fan data to milli-units * before calculating the exponent. */ - if (class == PSC_FAN) + if (sensor->class == PSC_FAN) val = val * 1000; /* Reduce large mantissa until it fits into 10 bit */ @@ -585,22 +586,22 @@ static u16 pmbus_data2reg_linear(struct pmbus_data *data, } static u16 pmbus_data2reg_direct(struct pmbus_data *data, - enum pmbus_sensor_classes class, long val) + struct pmbus_sensor *sensor, long val) { long m, b, R; - m = data->info->m[class]; - b = data->info->b[class]; - R = data->info->R[class]; + m = data->info->m[sensor->class]; + b = data->info->b[sensor->class]; + R = data->info->R[sensor->class]; /* Power is in uW. Adjust R and b. */ - if (class == PSC_POWER) { + if (sensor->class == PSC_POWER) { R -= 3; b *= 1000; } /* Calculate Y = (m * X + b) * 10^R */ - if (class != PSC_FAN) { + if (sensor->class != PSC_FAN) { R -= 3; /* Adjust R and b for data in milli-units */ b *= 1000; } @@ -619,7 +620,7 @@ static u16 pmbus_data2reg_direct(struct pmbus_data *data, } static u16 pmbus_data2reg_vid(struct pmbus_data *data, - enum pmbus_sensor_classes class, long val) + struct pmbus_sensor *sensor, long val) { val = clamp_val(val, 500, 1600); @@ -627,20 +628,20 @@ static u16 pmbus_data2reg_vid(struct pmbus_data *data, } static u16 pmbus_data2reg(struct pmbus_data *data, - enum pmbus_sensor_classes class, long val) + struct pmbus_sensor *sensor, long val) { u16 regval; - switch (data->info->format[class]) { + switch (data->info->format[sensor->class]) { case direct: - regval = pmbus_data2reg_direct(data, class, val); + regval = pmbus_data2reg_direct(data, sensor, val); break; case vid: - regval = pmbus_data2reg_vid(data, class, val); + regval = pmbus_data2reg_vid(data, sensor, val); break; case linear: default: - regval = pmbus_data2reg_linear(data, class, val); + regval = pmbus_data2reg_linear(data, sensor, val); break; } return regval; @@ -746,7 +747,7 @@ static ssize_t pmbus_set_sensor(struct device *dev, return -EINVAL; mutex_lock(&data->update_lock); - regval = pmbus_data2reg(data, sensor->class, val); + regval = pmbus_data2reg(data, sensor, val); ret = _pmbus_write_word_data(client, sensor->page, sensor->reg, regval); if (ret < 0) rv = ret; @@ -1643,12 +1644,13 @@ static int pmbus_find_attributes(struct i2c_client *client, * This function is called for all chips. */ static int pmbus_identify_common(struct i2c_client *client, - struct pmbus_data *data) + struct pmbus_data *data, int page) { int vout_mode = -1; - if (pmbus_check_byte_register(client, 0, PMBUS_VOUT_MODE)) - vout_mode = _pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE); + if (pmbus_check_byte_register(client, page, PMBUS_VOUT_MODE)) + vout_mode = _pmbus_read_byte_data(client, page, + PMBUS_VOUT_MODE); if (vout_mode >= 0 && vout_mode != 0xff) { /* * Not all chips support the VOUT_MODE command, @@ -1659,7 +1661,7 @@ static int pmbus_identify_common(struct i2c_client *client, if (data->info->format[PSC_VOLTAGE_OUT] != linear) return -ENODEV; - data->exponent = ((s8)(vout_mode << 3)) >> 3; + data->exponent[page] = ((s8)(vout_mode << 3)) >> 3; break; case 1: /* VID mode */ if (data->info->format[PSC_VOLTAGE_OUT] != vid) @@ -1674,7 +1676,7 @@ static int pmbus_identify_common(struct i2c_client *client, } } - pmbus_clear_fault_page(client, 0); + pmbus_clear_fault_page(client, page); return 0; } @@ -1682,7 +1684,7 @@ static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data, struct pmbus_driver_info *info) { struct device *dev = &client->dev; - int ret; + int page, ret; /* * Some PMBus chips don't support PMBUS_STATUS_BYTE, so try @@ -1715,10 +1717,12 @@ static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data, return -ENODEV; } - ret = pmbus_identify_common(client, data); - if (ret < 0) { - dev_err(dev, "Failed to identify chip capabilities\n"); - return ret; + for (page = 0; page < info->pages; page++) { + ret = pmbus_identify_common(client, data, page); + if (ret < 0) { + dev_err(dev, "Failed to identify chip capabilities\n"); + return ret; + } } return 0; } -- 2.41.0