From: Guillaume Roguez <[email protected]> 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 <[email protected]> Signed-off-by: Vivien Didelot <[email protected]> --- Documentation/hwmon/ads7828 | 11 +++++++++-- drivers/hwmon/Kconfig | 7 ++++--- drivers/hwmon/ads7828.c | 25 +++++++++++++++++++------ 3 files changed, 32 insertions(+), 11 deletions(-) diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828 index a987c94..f6e263e 100644 --- a/Documentation/hwmon/ads7828 +++ b/Documentation/hwmon/ads7828 @@ -7,9 +7,15 @@ Supported chips: Datasheet: Publicly available at the Texas Instruments website: http://focus.ti.com/lit/ds/symlink/ads7828.pdf + * Texas Instruments ADS7830 + Prefix: 'ads7830' + Datasheet: Publicly available at the Texas Instruments website: + http://focus.ti.com/lit/ds/symlink/ads7830.pdf + Authors: Steve Hardy <[email protected]> Vivien Didelot <[email protected]> + Guillaume Roguez <[email protected]> Platform data ------------- @@ -35,9 +41,10 @@ in include/linux/platform_data/ads7828.h). The structure fields are: Description ----------- -This driver implements support for the Texas Instruments ADS7828. +This driver implements support for the Texas Instruments ADS7828 and ADS7830. -This device is a 12-bit 8-channel A-D converter. +The ADS7828 device is a 12-bit 8-channel A/D converter, while the ADS7830 does +8-bit sampling. It can operate in single ended mode (8 +ve inputs) or in differential mode, where 4 differential pairs can be measured. diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 83e3e9d..960c8c5 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -1060,11 +1060,12 @@ config SENSORS_ADS1015 will be called ads1015. config SENSORS_ADS7828 - tristate "Texas Instruments ADS7828" + tristate "Texas Instruments ADS7828 and compatibles" depends on I2C help - If you say yes here you get support for Texas Instruments ADS7828 - 12-bit 8-channel ADC device. + If you say yes here you get support for Texas Instruments ADS7828 and + ADS7830 8-channel A/D converters. ADS7828 resolution is 12-bit, while + it is 8-bit on ADS7830. This driver can also be built as a module. If so, the module will be called ads7828. diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c index 42914fc..409b5c1 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 <[email protected]> * + * ADS7830 support, by Guillaume Roguez <[email protected]> + * * 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 <[email protected]>"); -MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter"); +MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles"); -- 1.7.11.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
