iio: dac: mcp4725: Add basic support for MCP4726
MCP4726 is a single channel 12-bit DAC. We can support MCP4726 with
a little changes to mcp4725 driver. In power-down mode, they have
different selection of VOUT pull-down registers.
MCP4726 also has features:
- Output gain options: 1x, 2x
- Voltage reference selection: VDD, VREF (Unbuffered or Buffered)
But these are not supported in this change. (1x gain, VDD is selected)
datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/22272C.pdf
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Peter Meerwald <pmeerw@pmeerw.net>
Cc: linux-iio@vger.kernel.org
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/dac/mcp4725.c b/drivers/iio/dac/mcp4725.c
index 43d1458..fb4b336 100644
--- a/drivers/iio/dac/mcp4725.c
+++ b/drivers/iio/dac/mcp4725.c
@@ -1,5 +1,5 @@
/*
- * mcp4725.c - Support for Microchip MCP4725
+ * mcp4725.c - Support for Microchip MCP4725/6
*
* Copyright (C) 2012 Peter Meerwald <pmeerw@pmeerw.net>
*
@@ -134,6 +134,12 @@
"500kohm_to_gnd"
};
+static const char * const mcp4726_powerdown_modes[] = {
+ "1kohm_to_gnd",
+ "125kohm_to_gnd",
+ "640kohm_to_gnd"
+};
+
static int mcp4725_get_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
@@ -182,11 +188,24 @@
return len;
}
-static const struct iio_enum mcp4725_powerdown_mode_enum = {
- .items = mcp4725_powerdown_modes,
- .num_items = ARRAY_SIZE(mcp4725_powerdown_modes),
- .get = mcp4725_get_powerdown_mode,
- .set = mcp4725_set_powerdown_mode,
+enum {
+ MCP4725,
+ MCP4726,
+};
+
+static const struct iio_enum mcp472x_powerdown_mode_enum[] = {
+ [MCP4725] = {
+ .items = mcp4725_powerdown_modes,
+ .num_items = ARRAY_SIZE(mcp4725_powerdown_modes),
+ .get = mcp4725_get_powerdown_mode,
+ .set = mcp4725_set_powerdown_mode,
+ },
+ [MCP4726] = {
+ .items = mcp4726_powerdown_modes,
+ .num_items = ARRAY_SIZE(mcp4726_powerdown_modes),
+ .get = mcp4725_get_powerdown_mode,
+ .set = mcp4725_set_powerdown_mode,
+ },
};
static const struct iio_chan_spec_ext_info mcp4725_ext_info[] = {
@@ -196,19 +215,46 @@
.write = mcp4725_write_powerdown,
.shared = IIO_SEPARATE,
},
- IIO_ENUM("powerdown_mode", IIO_SEPARATE, &mcp4725_powerdown_mode_enum),
- IIO_ENUM_AVAILABLE("powerdown_mode", &mcp4725_powerdown_mode_enum),
+ IIO_ENUM("powerdown_mode", IIO_SEPARATE,
+ &mcp472x_powerdown_mode_enum[MCP4725]),
+ IIO_ENUM_AVAILABLE("powerdown_mode",
+ &mcp472x_powerdown_mode_enum[MCP4725]),
{ },
};
-static const struct iio_chan_spec mcp4725_channel = {
- .type = IIO_VOLTAGE,
- .indexed = 1,
- .output = 1,
- .channel = 0,
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
- .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
- .ext_info = mcp4725_ext_info,
+static const struct iio_chan_spec_ext_info mcp4726_ext_info[] = {
+ {
+ .name = "powerdown",
+ .read = mcp4725_read_powerdown,
+ .write = mcp4725_write_powerdown,
+ .shared = IIO_SEPARATE,
+ },
+ IIO_ENUM("powerdown_mode", IIO_SEPARATE,
+ &mcp472x_powerdown_mode_enum[MCP4726]),
+ IIO_ENUM_AVAILABLE("powerdown_mode",
+ &mcp472x_powerdown_mode_enum[MCP4726]),
+ { },
+};
+
+static const struct iio_chan_spec mcp472x_channel[] = {
+ [MCP4725] = {
+ .type = IIO_VOLTAGE,
+ .indexed = 1,
+ .output = 1,
+ .channel = 0,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+ .ext_info = mcp4725_ext_info,
+ },
+ [MCP4726] = {
+ .type = IIO_VOLTAGE,
+ .indexed = 1,
+ .output = 1,
+ .channel = 0,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+ .ext_info = mcp4726_ext_info,
+ },
};
static int mcp4725_set_value(struct iio_dev *indio_dev, int val)
@@ -301,7 +347,7 @@
indio_dev->dev.parent = &client->dev;
indio_dev->info = &mcp4725_info;
- indio_dev->channels = &mcp4725_channel;
+ indio_dev->channels = &mcp472x_channel[id->driver_data];
indio_dev->num_channels = 1;
indio_dev->modes = INDIO_DIRECT_MODE;
@@ -315,7 +361,7 @@
}
pd = (inbuf[0] >> 1) & 0x3;
data->powerdown = pd > 0 ? true : false;
- data->powerdown_mode = pd ? pd-1 : 2; /* 500kohm_to_gnd */
+ data->powerdown_mode = pd ? pd - 1 : 2; /* largest register to gnd */
data->dac_value = (inbuf[1] << 4) | (inbuf[2] >> 4);
return iio_device_register(indio_dev);
@@ -328,7 +374,8 @@
}
static const struct i2c_device_id mcp4725_id[] = {
- { "mcp4725", 0 },
+ { "mcp4725", MCP4725 },
+ { "mcp4726", MCP4726 },
{ }
};
MODULE_DEVICE_TABLE(i2c, mcp4725_id);
@@ -345,5 +392,5 @@
module_i2c_driver(mcp4725_driver);
MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
-MODULE_DESCRIPTION("MCP4725 12-bit DAC");
+MODULE_DESCRIPTION("MCP4725/6 12-bit DAC");
MODULE_LICENSE("GPL");