hwmon: (ads1015) Add support for ADS1115

This patch adds support for ads1115 device to ads1015 driver.
Based on work of Emiliano Carnati <carnatiatebneuro.com>.
Tested on ARM CPU based board.

Signed-off-by: Evgeniy A. Dushistov <dushistov@mail.ru>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/Documentation/hwmon/ads1015 b/Documentation/hwmon/ads1015
index f6fe9c203733a9508cdfdc0c6b27e1d13921c3e1..063b80d857b1f86e54b2b31c89c77ffdff980847 100644 (file)
--- a/Documentation/hwmon/ads1015
+++ b/Documentation/hwmon/ads1015
@@ -6,6 +6,10 @@ Supported chips:
     Prefix: 'ads1015'
     Datasheet: Publicly available at the Texas Instruments website :
                http://focus.ti.com/lit/ds/symlink/ads1015.pdf
+  * Texas Instruments ADS1115
+    Prefix: 'ads1115'
+    Datasheet: Publicly available at the Texas Instruments website :
+               http://focus.ti.com/lit/ds/symlink/ads1115.pdf
 
 Authors:
         Dirk Eibach, Guntermann & Drunck GmbH <eibach@gdsys.de>
@@ -13,9 +17,9 @@ Authors:
 Description
 -----------
 
-This driver implements support for the Texas Instruments ADS1015.
+This driver implements support for the Texas Instruments ADS1015/ADS1115.
 
-This device is a 12-bit A-D converter with 4 inputs.
+This device is a 12/16-bit A-D converter with 4 inputs.
 
 The inputs can be used single ended or in certain differential combinations.
 

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index e989f7fd645b0d78322ba1431acf4c3f01c220b3..47b3e5821cb8bc070aa49f3257e663d6e4ec6173 100644 (file)
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1202,8 +1202,8 @@ config SENSORS_ADS1015
        tristate "Texas Instruments ADS1015"
        depends on I2C
        help
-         If you say yes here you get support for Texas Instruments ADS1015
-         12-bit 4-input ADC device.
+         If you say yes here you get support for Texas Instruments
+         ADS1015/ADS1115 12/16-bit 4-input ADC device.
 
          This driver can also be built as a module.  If so, the module
          will be called ads1015.

diff --git a/drivers/hwmon/ads1015.c b/drivers/hwmon/ads1015.c
index 2798246ad81470988fadd920dee5e9282f463445..7f9dc2f86b63d639a3a05baa3debc9b2cf724a19 100644 (file)
--- a/drivers/hwmon/ads1015.c
+++ b/drivers/hwmon/ads1015.c
@@ -46,17 +46,28 @@ static const unsigned int fullscale_table[8] = {
        6144, 4096, 2048, 1024, 512, 256, 256, 256 };
 
 /* Data rates in samples per second */
-static const unsigned int data_rate_table[8] = {
-       128, 250, 490, 920, 1600, 2400, 3300, 3300 };
+static const unsigned int data_rate_table_1015[8] = {
+       128, 250, 490, 920, 1600, 2400, 3300, 3300
+};
+
+static const unsigned int data_rate_table_1115[8] = {
+       8, 16, 32, 64, 128, 250, 475, 860
+};
 
 #define ADS1015_DEFAULT_CHANNELS 0xff
 #define ADS1015_DEFAULT_PGA 2
 #define ADS1015_DEFAULT_DATA_RATE 4
 
+enum ads1015_chips {
+       ads1015,
+       ads1115,
+};
+
 struct ads1015_data {
        struct device *hwmon_dev;
        struct mutex update_lock; /* mutex protect updates */
        struct ads1015_channel_data channel_data[ADS1015_CHANNELS];
+       enum ads1015_chips id;
 };
 
 static int ads1015_read_adc(struct i2c_client *client, unsigned int channel)
@@ -66,6 +77,8 @@ static int ads1015_read_adc(struct i2c_client *client, unsigned int channel)
        unsigned int pga = data->channel_data[channel].pga;
        unsigned int data_rate = data->channel_data[channel].data_rate;
        unsigned int conversion_time_ms;
+       const unsigned int * const rate_table = data->id == ads1115 ?
+               data_rate_table_1115 : data_rate_table_1015;
        int res;
 
        mutex_lock(&data->update_lock);
@@ -75,7 +88,7 @@ static int ads1015_read_adc(struct i2c_client *client, unsigned int channel)
        if (res < 0)
                goto err_unlock;
        config = res;
-       conversion_time_ms = DIV_ROUND_UP(1000, data_rate_table[data_rate]);
+       conversion_time_ms = DIV_ROUND_UP(1000, rate_table[data_rate]);
 
        /* setup and start single conversion */
        config &= 0x001f;
@@ -113,8 +126,9 @@ static int ads1015_reg_to_mv(struct i2c_client *client, unsigned int channel,
        struct ads1015_data *data = i2c_get_clientdata(client);
        unsigned int pga = data->channel_data[channel].pga;
        int fullscale = fullscale_table[pga];
+       const unsigned mask = data->id == ads1115 ? 0x7fff : 0x7ff0;
 
-       return DIV_ROUND_CLOSEST(reg * fullscale, 0x7ff0);
+       return DIV_ROUND_CLOSEST(reg * fullscale, mask);
 }
 
 /* sysfs callback function */
@@ -257,7 +271,7 @@ static int ads1015_probe(struct i2c_client *client,
                            GFP_KERNEL);
        if (!data)
                return -ENOMEM;
-
+       data->id = id->driver_data;
        i2c_set_clientdata(client, data);
        mutex_init(&data->update_lock);
 
@@ -286,7 +300,8 @@ exit_remove:
 }
 
 static const struct i2c_device_id ads1015_id[] = {
-       { "ads1015", 0 },
+       { "ads1015",  ads1015},
+       { "ads1115",  ads1115},
        { }
 };
 MODULE_DEVICE_TABLE(i2c, ads1015_id);