On 05/20/2010 02:50 PM, Andre Prendel wrote: > You made a careless mistake, see below. Please fix this and resend the patch > again. Then I added my Acked-by and I think Jean will schedule the patch for > 2.6.35 (after another review of course :)) You sir, would be correct... *sigh* I tried using the scripts/Lindent on it to be sure there were no coding style issues but that messed up even your original code. In any event, here it is again: >From 9acd29ff48c64e58a7f5cdb888c86e737c56281c Mon Sep 17 00:00:00 2001 From: Jeff Angielski <jeff@xxxxxxxxxxxxxxx> Date: Mon, 10 May 2010 10:26:34 -0400 Subject: [PATCH] hwmon: (tmp421) Add nfactor support Add support for reading and writing the n-factor correction registers. This is needed to compensate for the characteristics of a particular sensor hanging off of the remote channels. Signed-off-by: Jeff Angielski <jeff@xxxxxxxxxxxxxxx> --- Documentation/hwmon/tmp421 | 19 +++++++++++++++++++ drivers/hwmon/tmp421.c | 41 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 60 insertions(+), 0 deletions(-) diff --git a/Documentation/hwmon/tmp421 b/Documentation/hwmon/tmp421 index 0cf07f8..668228a 100644 --- a/Documentation/hwmon/tmp421 +++ b/Documentation/hwmon/tmp421 @@ -17,6 +17,7 @@ Supported chips: Authors: Andre Prendel <andre.prendel@xxxxxx> + Jeff Angielski <jeff@xxxxxxxxxxxxxxx> Description ----------- @@ -34,3 +35,21 @@ the temperature values via the following sysfs files: temp[1-4]_input temp[2-4]_fault + +The chips allow the user to adjust the n-factor value that is used +when converting the remote channel measurements to temperature. The +adjustment has a range of -128 to +127 that yields an effective +n-factor range of 0.706542 to 1.747977. The power on reset value +for the adjustment is 0 which results in an n-factor of 1.008. + +The effective n-factor is calculated according to the following +equation: + +n_factor = (1.008 * 300) / (300 - nfactor_adjust) + +The driver exports the n-factor adjustment value via the following +sysfs files: + +temp[2-4]_n_adjust + + diff --git a/drivers/hwmon/tmp421.c b/drivers/hwmon/tmp421.c index 738c472..dfd62be 100644 --- a/drivers/hwmon/tmp421.c +++ b/drivers/hwmon/tmp421.c @@ -49,6 +49,7 @@ enum chips { tmp421, tmp422, tmp423 }; static const u8 TMP421_TEMP_MSB[4] = { 0x00, 0x01, 0x02, 0x03 }; static const u8 TMP421_TEMP_LSB[4] = { 0x10, 0x11, 0x12, 0x13 }; +static const u8 TMP421_N_CORRECT[3] = { 0x21, 0x22, 0x23 }; /* Flags */ #define TMP421_CONFIG_SHUTDOWN 0x40 @@ -76,6 +77,7 @@ struct tmp421_data { int channels; u8 config; s16 temp[4]; + s8 n_adjust[3]; }; static int temp_from_s16(s16 reg) @@ -115,6 +117,10 @@ static struct tmp421_data *tmp421_update_device(struct device *dev) data->temp[i] |= i2c_smbus_read_byte_data(client, TMP421_TEMP_LSB[i]); } + for (i = 1; i < data->channels; i++) { + data->n_adjust[i - 1] = i2c_smbus_read_byte_data(client, + TMP421_N_CORRECT[i - 1]); + } data->last_updated = jiffies; data->valid = 1; } @@ -157,6 +163,32 @@ static ssize_t show_fault(struct device *dev, return sprintf(buf, "0\n"); } +static ssize_t show_n_adjust(struct device *dev, + struct device_attribute *devattr, char *buf) +{ + int index = to_sensor_dev_attr(devattr)->index; + struct tmp421_data *data = tmp421_update_device(dev); + + return sprintf(buf, "%d\n", data->n_adjust[index - 1]); +} + +static ssize_t set_n_adjust(struct device *dev, + struct device_attribute *devattr, + const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + struct tmp421_data *data = i2c_get_clientdata(client); + int index = to_sensor_dev_attr(devattr)->index; + int n_adjust = simple_strtol(buf, NULL, 10); + + mutex_lock(&data->update_lock); + i2c_smbus_write_byte_data(client, TMP421_N_CORRECT[index - 1], + SENSORS_LIMIT(n_adjust, -128, 127)); + mutex_unlock(&data->update_lock); + + return count; +} + static mode_t tmp421_is_visible(struct kobject *kobj, struct attribute *a, int n) { @@ -177,19 +209,28 @@ static mode_t tmp421_is_visible(struct kobject *kobj, struct attribute *a, static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_value, NULL, 0); static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_value, NULL, 1); static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_fault, NULL, 1); +static SENSOR_DEVICE_ATTR(temp2_n_adjust, S_IRUSR | S_IWUSR | S_IRGRP, + show_n_adjust, set_n_adjust, 1); static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp_value, NULL, 2); static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_fault, NULL, 2); +static SENSOR_DEVICE_ATTR(temp3_n_adjust, S_IRUSR | S_IWUSR | S_IRGRP, + show_n_adjust, set_n_adjust, 2); static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp_value, NULL, 3); static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_fault, NULL, 3); +static SENSOR_DEVICE_ATTR(temp4_n_adjust, S_IRUSR | S_IWUSR | S_IRGRP, + show_n_adjust, set_n_adjust, 3); static struct attribute *tmp421_attr[] = { &sensor_dev_attr_temp1_input.dev_attr.attr, &sensor_dev_attr_temp2_input.dev_attr.attr, &sensor_dev_attr_temp2_fault.dev_attr.attr, + &sensor_dev_attr_temp2_n_adjust.dev_attr.attr, &sensor_dev_attr_temp3_input.dev_attr.attr, &sensor_dev_attr_temp3_fault.dev_attr.attr, + &sensor_dev_attr_temp3_n_adjust.dev_attr.attr, &sensor_dev_attr_temp4_input.dev_attr.attr, &sensor_dev_attr_temp4_fault.dev_attr.attr, + &sensor_dev_attr_temp4_n_adjust.dev_attr.attr, NULL }; -- 1.7.0.4 -- Jeff Angielski The PTR Group www.theptrgroup.com _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors