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path: root/drivers/iio/dac/mcp4725.c
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Diffstat (limited to 'drivers/iio/dac/mcp4725.c')
-rw-r--r--drivers/iio/dac/mcp4725.c176
1 files changed, 160 insertions, 16 deletions
diff --git a/drivers/iio/dac/mcp4725.c b/drivers/iio/dac/mcp4725.c
index cca935c06f2b..db109f0cdd8c 100644
--- a/drivers/iio/dac/mcp4725.c
+++ b/drivers/iio/dac/mcp4725.c
@@ -18,6 +18,8 @@
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/delay.h>
+#include <linux/regulator/consumer.h>
+#include <linux/of.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
@@ -26,12 +28,20 @@
#define MCP4725_DRV_NAME "mcp4725"
+#define MCP472X_REF_VDD 0x00
+#define MCP472X_REF_VREF_UNBUFFERED 0x02
+#define MCP472X_REF_VREF_BUFFERED 0x03
+
struct mcp4725_data {
struct i2c_client *client;
- u16 vref_mv;
+ int id;
+ unsigned ref_mode;
+ bool vref_buffered;
u16 dac_value;
bool powerdown;
unsigned powerdown_mode;
+ struct regulator *vdd_reg;
+ struct regulator *vref_reg;
};
static int mcp4725_suspend(struct device *dev)
@@ -86,6 +96,7 @@ static ssize_t mcp4725_store_eeprom(struct device *dev,
return 0;
inoutbuf[0] = 0x60; /* write EEPROM */
+ inoutbuf[0] |= data->ref_mode << 3;
inoutbuf[1] = data->dac_value >> 4;
inoutbuf[2] = (data->dac_value & 0xf) << 4;
@@ -278,18 +289,49 @@ static int mcp4725_set_value(struct iio_dev *indio_dev, int val)
return 0;
}
+static int mcp4726_set_cfg(struct iio_dev *indio_dev)
+{
+ struct mcp4725_data *data = iio_priv(indio_dev);
+ u8 outbuf[3];
+ int ret;
+
+ outbuf[0] = 0x40;
+ outbuf[0] |= data->ref_mode << 3;
+ if (data->powerdown)
+ outbuf[0] |= data->powerdown << 1;
+ outbuf[1] = data->dac_value >> 4;
+ outbuf[2] = (data->dac_value & 0xf) << 4;
+
+ ret = i2c_master_send(data->client, outbuf, 3);
+ if (ret < 0)
+ return ret;
+ else if (ret != 3)
+ return -EIO;
+ else
+ return 0;
+}
+
static int mcp4725_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct mcp4725_data *data = iio_priv(indio_dev);
+ int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
*val = data->dac_value;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
- *val = data->vref_mv;
+ if (data->ref_mode == MCP472X_REF_VDD)
+ ret = regulator_get_voltage(data->vdd_reg);
+ else
+ ret = regulator_get_voltage(data->vref_reg);
+
+ if (ret < 0)
+ return ret;
+
+ *val = ret / 1000;
*val2 = 12;
return IIO_VAL_FRACTIONAL_LOG2;
}
@@ -323,27 +365,98 @@ static const struct iio_info mcp4725_info = {
.driver_module = THIS_MODULE,
};
+#ifdef CONFIG_OF
+static int mcp4725_probe_dt(struct device *dev,
+ struct mcp4725_platform_data *pdata)
+{
+ struct device_node *np = dev->of_node;
+
+ if (!np)
+ return -ENODEV;
+
+ /* check if is the vref-supply defined */
+ pdata->use_vref = of_property_read_bool(np, "vref-supply");
+ pdata->vref_buffered =
+ of_property_read_bool(np, "microchip,vref-buffered");
+
+ return 0;
+}
+#else
+static int mcp4725_probe_dt(struct device *dev,
+ struct mcp4725_platform_data *platform_data)
+{
+ return -ENODEV;
+}
+#endif
+
static int mcp4725_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct mcp4725_data *data;
struct iio_dev *indio_dev;
- struct mcp4725_platform_data *platform_data = client->dev.platform_data;
- u8 inbuf[3];
+ struct mcp4725_platform_data *pdata, pdata_dt;
+ u8 inbuf[4];
u8 pd;
+ u8 ref;
int err;
- if (!platform_data || !platform_data->vref_mv) {
- dev_err(&client->dev, "invalid platform data");
- return -EINVAL;
- }
-
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (indio_dev == NULL)
return -ENOMEM;
data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->client = client;
+ data->id = id->driver_data;
+ pdata = dev_get_platdata(&client->dev);
+
+ if (!pdata) {
+ err = mcp4725_probe_dt(&client->dev, &pdata_dt);
+ if (err) {
+ dev_err(&client->dev,
+ "invalid platform or devicetree data");
+ return err;
+ }
+ pdata = &pdata_dt;
+ }
+
+ if (data->id == MCP4725 && pdata->use_vref) {
+ dev_err(&client->dev,
+ "external reference is unavailable on MCP4725");
+ return -EINVAL;
+ }
+
+ if (!pdata->use_vref && pdata->vref_buffered) {
+ dev_err(&client->dev,
+ "buffering is unavailable on the internal reference");
+ return -EINVAL;
+ }
+
+ if (!pdata->use_vref)
+ data->ref_mode = MCP472X_REF_VDD;
+ else
+ data->ref_mode = pdata->vref_buffered ?
+ MCP472X_REF_VREF_BUFFERED :
+ MCP472X_REF_VREF_UNBUFFERED;
+
+ data->vdd_reg = devm_regulator_get(&client->dev, "vdd");
+ if (IS_ERR(data->vdd_reg))
+ return PTR_ERR(data->vdd_reg);
+
+ err = regulator_enable(data->vdd_reg);
+ if (err)
+ return err;
+
+ if (pdata->use_vref) {
+ data->vref_reg = devm_regulator_get(&client->dev, "vref");
+ if (IS_ERR(data->vref_reg)) {
+ err = PTR_ERR(data->vref_reg);
+ goto err_disable_vdd_reg;
+ }
+
+ err = regulator_enable(data->vref_reg);
+ if (err)
+ goto err_disable_vdd_reg;
+ }
indio_dev->dev.parent = &client->dev;
indio_dev->name = id->name;
@@ -352,25 +465,56 @@ static int mcp4725_probe(struct i2c_client *client,
indio_dev->num_channels = 1;
indio_dev->modes = INDIO_DIRECT_MODE;
- data->vref_mv = platform_data->vref_mv;
+ /* read current DAC value and settings */
+ err = i2c_master_recv(client, inbuf, data->id == MCP4725 ? 3 : 4);
- /* read current DAC value */
- err = i2c_master_recv(client, inbuf, 3);
if (err < 0) {
dev_err(&client->dev, "failed to read DAC value");
- return err;
+ goto err_disable_vref_reg;
}
pd = (inbuf[0] >> 1) & 0x3;
data->powerdown = pd > 0 ? true : false;
- data->powerdown_mode = pd ? pd - 1 : 2; /* largest register to gnd */
+ data->powerdown_mode = pd ? pd - 1 : 2; /* largest resistor to gnd */
data->dac_value = (inbuf[1] << 4) | (inbuf[2] >> 4);
+ if (data->id == MCP4726)
+ ref = (inbuf[3] >> 3) & 0x3;
+
+ if (data->id == MCP4726 && ref != data->ref_mode) {
+ dev_info(&client->dev,
+ "voltage reference mode differs (conf: %u, eeprom: %u), setting %u",
+ data->ref_mode, ref, data->ref_mode);
+ err = mcp4726_set_cfg(indio_dev);
+ if (err < 0)
+ goto err_disable_vref_reg;
+ }
+
+ err = iio_device_register(indio_dev);
+ if (err)
+ goto err_disable_vref_reg;
+
+ return 0;
+
+err_disable_vref_reg:
+ if (data->vref_reg)
+ regulator_disable(data->vref_reg);
- return iio_device_register(indio_dev);
+err_disable_vdd_reg:
+ regulator_disable(data->vdd_reg);
+
+ return err;
}
static int mcp4725_remove(struct i2c_client *client)
{
- iio_device_unregister(i2c_get_clientdata(client));
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ struct mcp4725_data *data = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+
+ if (data->vref_reg)
+ regulator_disable(data->vref_reg);
+ regulator_disable(data->vdd_reg);
+
return 0;
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-05 02:53:18 +0300