diff options
| author | Guillaume Roguez <guillaume.roguez@savoirfairelinux.com> | 2012-10-04 00:54:08 +0400 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2012-12-05 22:55:54 +0400 |
| commit | 0962e0f1a5634b63953db2c12edcff938f9d811d (patch) | |
| tree | 698edc816261f42f0acd810f8f15a9fa70234e6f /drivers/hwmon/ads7828.c | |
| parent | 46d784629202c5da9be8d727988e7083fb455bf8 (diff) | |
| download | linux-0962e0f1a5634b63953db2c12edcff938f9d811d.tar.xz | |
hwmon: (ads7828) add support for ADS7830
The ADS7830 device is almost the same as the ADS7828,
except that it does 8-bit sampling, instead of 12-bit.
This patch extends the ads7828 driver to support this chip.
Signed-off-by: Guillaume Roguez <guillaume.roguez@savoirfairelinux.com>
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon/ads7828.c')
| -rw-r--r-- | drivers/hwmon/ads7828.c | 25 |
1 files changed, 19 insertions, 6 deletions
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c index 42914fc1436d..409b5c16defb 100644 --- a/drivers/hwmon/ads7828.c +++ b/drivers/hwmon/ads7828.c @@ -1,11 +1,13 @@ /* - * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC + * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles * (C) 2007 EADS Astrium * * This driver is based on the lm75 and other lm_sensors/hwmon drivers * * Written by Steve Hardy <shardy@redhat.com> * + * ADS7830 support, by Guillaume Roguez <guillaume.roguez@savoirfairelinux.com> + * * For further information, see the Documentation/hwmon/ads7828 file. * * This program is free software; you can redistribute it and/or modify @@ -43,6 +45,9 @@ #define ADS7828_EXT_VREF_MV_MIN 50 /* External vref min value 0.05V */ #define ADS7828_EXT_VREF_MV_MAX 5250 /* External vref max value 5.25V */ +/* List of supported devices */ +enum ads7828_chips { ads7828, ads7830 }; + /* Client specific data */ struct ads7828_data { struct device *hwmon_dev; @@ -55,6 +60,7 @@ struct ads7828_data { unsigned int vref_mv; /* voltage reference value */ u8 cmd_byte; /* Command byte without channel bits */ unsigned int lsb_resol; /* Resolution of the ADC sample LSB */ + s32 (*read_channel)(const struct i2c_client *client, u8 command); }; /* Command byte C2,C1,C0 - see datasheet */ @@ -78,8 +84,7 @@ static struct ads7828_data *ads7828_update_device(struct device *dev) for (ch = 0; ch < ADS7828_NCH; ch++) { u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch); - data->adc_input[ch] = - i2c_smbus_read_word_swapped(client, cmd); + data->adc_input[ch] = data->read_channel(client, cmd); } data->last_updated = jiffies; data->valid = true; @@ -164,7 +169,14 @@ static int ads7828_probe(struct i2c_client *client, else data->vref_mv = ADS7828_INT_VREF_MV; - data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096); + /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */ + if (id->driver_data == ads7828) { + data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096); + data->read_channel = i2c_smbus_read_word_swapped; + } else { + data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 256); + data->read_channel = i2c_smbus_read_byte_data; + } data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3; if (!data->diff_input) @@ -191,7 +203,8 @@ error: } static const struct i2c_device_id ads7828_device_ids[] = { - { "ads7828", 0 }, + { "ads7828", ads7828 }, + { "ads7830", ads7830 }, { } }; MODULE_DEVICE_TABLE(i2c, ads7828_device_ids); @@ -210,4 +223,4 @@ module_i2c_driver(ads7828_driver); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Steve Hardy <shardy@redhat.com>"); -MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter"); +MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles"); |