]> git.karo-electronics.de Git - linux-beck.git/blobdiff - drivers/iio/adc/ti-adc081c.c
Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszer...
[linux-beck.git] / drivers / iio / adc / ti-adc081c.c
index ecbc12138d589d5379ab51b744942b64822115d8..9fd032d9f402fbd57e58d77f186ca66410148d78 100644 (file)
@@ -1,9 +1,21 @@
 /*
+ * TI ADC081C/ADC101C/ADC121C 8/10/12-bit ADC driver
+ *
  * Copyright (C) 2012 Avionic Design GmbH
+ * Copyright (C) 2016 Intel
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
+ *
+ * Datasheets:
+ *     http://www.ti.com/lit/ds/symlink/adc081c021.pdf
+ *     http://www.ti.com/lit/ds/symlink/adc101c021.pdf
+ *     http://www.ti.com/lit/ds/symlink/adc121c021.pdf
+ *
+ * The devices have a very similar interface and differ mostly in the number of
+ * bits handled. For the 8-bit and 10-bit models the least-significant 4 or 2
+ * bits of value registers are reserved.
  */
 
 #include <linux/err.h>
 #include <linux/of.h>
 
 #include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
 #include <linux/regulator/consumer.h>
 
 struct adc081c {
        struct i2c_client *i2c;
        struct regulator *ref;
+
+       /* 8, 10 or 12 */
+       int bits;
 };
 
 #define REG_CONV_RES 0x00
@@ -34,7 +52,7 @@ static int adc081c_read_raw(struct iio_dev *iio,
                if (err < 0)
                        return err;
 
-               *value = (err >> 4) & 0xff;
+               *value = (err & 0xFFF) >> (12 - adc->bits);
                return IIO_VAL_INT;
 
        case IIO_CHAN_INFO_SCALE:
@@ -43,7 +61,7 @@ static int adc081c_read_raw(struct iio_dev *iio,
                        return err;
 
                *value = err / 1000;
-               *shift = 8;
+               *shift = adc->bits;
 
                return IIO_VAL_FRACTIONAL_LOG2;
 
@@ -54,10 +72,53 @@ static int adc081c_read_raw(struct iio_dev *iio,
        return -EINVAL;
 }
 
-static const struct iio_chan_spec adc081c_channel = {
-       .type = IIO_VOLTAGE,
-       .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
-       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+#define ADCxx1C_CHAN(_bits) {                                  \
+       .type = IIO_VOLTAGE,                                    \
+       .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),   \
+       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),           \
+       .scan_type = {                                          \
+               .sign = 'u',                                    \
+               .realbits = (_bits),                            \
+               .storagebits = 16,                              \
+               .shift = 12 - (_bits),                          \
+               .endianness = IIO_CPU,                          \
+       },                                                      \
+}
+
+#define DEFINE_ADCxx1C_CHANNELS(_name, _bits)                          \
+       static const struct iio_chan_spec _name ## _channels[] = {      \
+               ADCxx1C_CHAN((_bits)),                                  \
+               IIO_CHAN_SOFT_TIMESTAMP(1),                             \
+       };                                                              \
+
+#define ADC081C_NUM_CHANNELS 2
+
+struct adcxx1c_model {
+       const struct iio_chan_spec* channels;
+       int bits;
+};
+
+#define ADCxx1C_MODEL(_name, _bits)                                    \
+       {                                                               \
+               .channels = _name ## _channels,                         \
+               .bits = (_bits),                                        \
+       }
+
+DEFINE_ADCxx1C_CHANNELS(adc081c,  8);
+DEFINE_ADCxx1C_CHANNELS(adc101c, 10);
+DEFINE_ADCxx1C_CHANNELS(adc121c, 12);
+
+/* Model ids are indexes in _models array */
+enum adcxx1c_model_id {
+       ADC081C = 0,
+       ADC101C = 1,
+       ADC121C = 2,
+};
+
+static struct adcxx1c_model adcxx1c_models[] = {
+       ADCxx1C_MODEL(adc081c,  8),
+       ADCxx1C_MODEL(adc101c, 10),
+       ADCxx1C_MODEL(adc121c, 12),
 };
 
 static const struct iio_info adc081c_info = {
@@ -65,11 +126,30 @@ static const struct iio_info adc081c_info = {
        .driver_module = THIS_MODULE,
 };
 
+static irqreturn_t adc081c_trigger_handler(int irq, void *p)
+{
+       struct iio_poll_func *pf = p;
+       struct iio_dev *indio_dev = pf->indio_dev;
+       struct adc081c *data = iio_priv(indio_dev);
+       u16 buf[8]; /* 2 bytes data + 6 bytes padding + 8 bytes timestamp */
+       int ret;
+
+       ret = i2c_smbus_read_word_swapped(data->i2c, REG_CONV_RES);
+       if (ret < 0)
+               goto out;
+       buf[0] = ret;
+       iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns());
+out:
+       iio_trigger_notify_done(indio_dev->trig);
+       return IRQ_HANDLED;
+}
+
 static int adc081c_probe(struct i2c_client *client,
                         const struct i2c_device_id *id)
 {
        struct iio_dev *iio;
        struct adc081c *adc;
+       struct adcxx1c_model *model = &adcxx1c_models[id->driver_data];
        int err;
 
        if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
@@ -81,6 +161,7 @@ static int adc081c_probe(struct i2c_client *client,
 
        adc = iio_priv(iio);
        adc->i2c = client;
+       adc->bits = model->bits;
 
        adc->ref = devm_regulator_get(&client->dev, "vref");
        if (IS_ERR(adc->ref))
@@ -95,18 +176,26 @@ static int adc081c_probe(struct i2c_client *client,
        iio->modes = INDIO_DIRECT_MODE;
        iio->info = &adc081c_info;
 
-       iio->channels = &adc081c_channel;
-       iio->num_channels = 1;
+       iio->channels = model->channels;
+       iio->num_channels = ADC081C_NUM_CHANNELS;
+
+       err = iio_triggered_buffer_setup(iio, NULL, adc081c_trigger_handler, NULL);
+       if (err < 0) {
+               dev_err(&client->dev, "iio triggered buffer setup failed\n");
+               goto err_regulator_disable;
+       }
 
        err = iio_device_register(iio);
        if (err < 0)
-               goto regulator_disable;
+               goto err_buffer_cleanup;
 
        i2c_set_clientdata(client, iio);
 
        return 0;
 
-regulator_disable:
+err_buffer_cleanup:
+       iio_triggered_buffer_cleanup(iio);
+err_regulator_disable:
        regulator_disable(adc->ref);
 
        return err;
@@ -118,13 +207,16 @@ static int adc081c_remove(struct i2c_client *client)
        struct adc081c *adc = iio_priv(iio);
 
        iio_device_unregister(iio);
+       iio_triggered_buffer_cleanup(iio);
        regulator_disable(adc->ref);
 
        return 0;
 }
 
 static const struct i2c_device_id adc081c_id[] = {
-       { "adc081c", 0 },
+       { "adc081c", ADC081C },
+       { "adc101c", ADC101C },
+       { "adc121c", ADC121C },
        { }
 };
 MODULE_DEVICE_TABLE(i2c, adc081c_id);
@@ -132,6 +224,8 @@ MODULE_DEVICE_TABLE(i2c, adc081c_id);
 #ifdef CONFIG_OF
 static const struct of_device_id adc081c_of_match[] = {
        { .compatible = "ti,adc081c" },
+       { .compatible = "ti,adc101c" },
+       { .compatible = "ti,adc121c" },
        { }
 };
 MODULE_DEVICE_TABLE(of, adc081c_of_match);
@@ -149,5 +243,5 @@ static struct i2c_driver adc081c_driver = {
 module_i2c_driver(adc081c_driver);
 
 MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
-MODULE_DESCRIPTION("Texas Instruments ADC081C021/027 driver");
+MODULE_DESCRIPTION("Texas Instruments ADC081C/ADC101C/ADC121C driver");
 MODULE_LICENSE("GPL v2");