Re: [PATCHv3] iio: adc: add driver for MCP3204/08 12-bit ADC
On 05/03/2013 10:55 AM, Oskar Andero wrote:
[...]
> +
> +struct mcp320x {
> + struct spi_device *spi;
> + struct spi_message msg;
> + struct spi_transfer transfer[2];
> +
> + u8 tx_buf;
> + u8 rx_buf[2];
> +
> + struct regulator *reg;
> + unsigned int ref_mv;
ref_mv looks unused.
> +
> + struct mutex lock;
> +};
> +
[..]
> +static int mcp320x_probe(struct spi_device *spi)
> +{
[...]
> +
> + ret = regulator_enable(adc->reg);
> + if (ret < 0)
> + goto reg_free;
You shouldn't disable the regulator if enabling it failed.
> +
> + mutex_init(>lock);
> +
> + ret = iio_device_register(indio_dev);
> + if (ret < 0)
> + goto reg_free;
> +
> + return 0;
> +
> +reg_free:
> + regulator_disable(adc->reg);
> + regulator_put(adc->reg);
> +iio_free:
> + iio_device_free(indio_dev);
> +
> + return ret;
> +}
[...]
--
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[PATCHv3] iio: adc: add driver for MCP3204/08 12-bit ADC
This adds support for Microchip's 12 bit AD converters MCP3204 and
MCP3208. These chips communicates over SPI and supports single-ended
and pseudo-differential configurations.
Cc: Jonathan Cameron
Cc: Lars-Peter Clausen
Signed-off-by: Oskar Andero
---
drivers/iio/adc/Kconfig | 10 ++
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/mcp320x.c | 258 ++
3 files changed, 269 insertions(+)
create mode 100644 drivers/iio/adc/mcp320x.c
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index ab0767e6..93129ec 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -133,6 +133,16 @@ config MAX1363
max11646, max11647) Provides direct access via sysfs and buffered
data via the iio dev interface.
+config MCP320X
+ tristate "Microchip Technology MCP3204/08"
+ depends on SPI
+ help
+ Say yes here to build support for Microchip Technology's MCP3204 or
+ MCP3208 analog to digital converter.
+
+ This driver can also be built as a module. If so, the module will be
+ called mcp320x.
+
config TI_ADC081C
tristate "Texas Instruments ADC081C021/027"
depends on I2C
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 0a825be..8f475d3 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_AT91_ADC) += at91_adc.o
obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
obj-$(CONFIG_MAX1363) += max1363.o
+obj-$(CONFIG_MCP320X) += mcp320x.o
obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o
diff --git a/drivers/iio/adc/mcp320x.c b/drivers/iio/adc/mcp320x.c
new file mode 100644
index 000..b38bf87
--- /dev/null
+++ b/drivers/iio/adc/mcp320x.c
@@ -0,0 +1,258 @@
+/*
+ * Copyright (C) 2013 Oskar Andero
+ *
+ * Driver for Microchip Technology's MCP3204 and MCP3208 ADC chips.
+ * Datasheet can be found here:
+ * http://ww1.microchip.com/downloads/en/devicedoc/21298c.pdf
+ *
+ * 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.
+ */
+
+#include
+#include
+#include
+#include
+#include
+
+#define MCP_SINGLE_ENDED (1 << 3)
+#define MCP_START_BIT (1 << 4)
+
+enum {
+ mcp3204,
+ mcp3208,
+};
+
+struct mcp320x {
+ struct spi_device *spi;
+ struct spi_message msg;
+ struct spi_transfer transfer[2];
+
+ u8 tx_buf;
+ u8 rx_buf[2];
+
+ struct regulator *reg;
+ unsigned int ref_mv;
+
+ struct mutex lock;
+};
+
+static int mcp320x_adc_conversion(struct mcp320x *adc, u8 msg)
+{
+ int ret;
+
+ adc->tx_buf = msg;
+ ret = spi_sync(adc->spi, >msg);
+ if (ret < 0)
+ return ret;
+
+ return ((adc->rx_buf[0] & 0x3f) << 6) |
+ (adc->rx_buf[1] >> 2);
+}
+
+static int mcp320x_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *channel, int *val,
+ int *val2, long mask)
+{
+ struct mcp320x *adc = iio_priv(indio_dev);
+ int ret = -EINVAL;
+
+ mutex_lock(>lock);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (channel->differential)
+ ret = mcp320x_adc_conversion(adc,
+ MCP_START_BIT | channel->address);
+ else
+ ret = mcp320x_adc_conversion(adc,
+ MCP_START_BIT | MCP_SINGLE_ENDED |
+ channel->address);
+ if (ret < 0)
+ goto out;
+
+ *val = ret;
+ ret = IIO_VAL_INT;
+ break;
+
+ case IIO_CHAN_INFO_SCALE:
+ /* Digital output code = (4096 * Vin) / Vref */
+ ret = regulator_get_voltage(adc->reg);
+ if (ret < 0)
+ goto out;
+
+ *val = ret / 1000;
+ *val2 = 12;
+ ret = IIO_VAL_FRACTIONAL_LOG2;
+ break;
+
+ default:
+ break;
+ }
+
+out:
+ mutex_unlock(>lock);
+
+ return ret;
+}
+
+#define MCP320X_VOLTAGE_CHANNEL(num) \
+ { \
+ .type = IIO_VOLTAGE,\
+ .indexed = 1, \
+ .channel = (num), \
+ .address = (num), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \
+ }
+
+#define MCP320X_VOLTAGE_CHANNEL_DIFF(num)
[PATCHv3] iio: adc: add driver for MCP3204/08 12-bit ADC
This adds support for Microchip's 12 bit AD converters MCP3204 and
MCP3208. These chips communicates over SPI and supports single-ended
and pseudo-differential configurations.
Cc: Jonathan Cameron ji...@cam.ac.uk
Cc: Lars-Peter Clausen l...@metafoo.de
Signed-off-by: Oskar Andero oskar.and...@gmail.com
---
drivers/iio/adc/Kconfig | 10 ++
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/mcp320x.c | 258 ++
3 files changed, 269 insertions(+)
create mode 100644 drivers/iio/adc/mcp320x.c
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index ab0767e6..93129ec 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -133,6 +133,16 @@ config MAX1363
max11646, max11647) Provides direct access via sysfs and buffered
data via the iio dev interface.
+config MCP320X
+ tristate Microchip Technology MCP3204/08
+ depends on SPI
+ help
+ Say yes here to build support for Microchip Technology's MCP3204 or
+ MCP3208 analog to digital converter.
+
+ This driver can also be built as a module. If so, the module will be
+ called mcp320x.
+
config TI_ADC081C
tristate Texas Instruments ADC081C021/027
depends on I2C
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 0a825be..8f475d3 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_AT91_ADC) += at91_adc.o
obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
obj-$(CONFIG_MAX1363) += max1363.o
+obj-$(CONFIG_MCP320X) += mcp320x.o
obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o
diff --git a/drivers/iio/adc/mcp320x.c b/drivers/iio/adc/mcp320x.c
new file mode 100644
index 000..b38bf87
--- /dev/null
+++ b/drivers/iio/adc/mcp320x.c
@@ -0,0 +1,258 @@
+/*
+ * Copyright (C) 2013 Oskar Andero oskar.and...@gmail.com
+ *
+ * Driver for Microchip Technology's MCP3204 and MCP3208 ADC chips.
+ * Datasheet can be found here:
+ * http://ww1.microchip.com/downloads/en/devicedoc/21298c.pdf
+ *
+ * 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.
+ */
+
+#include linux/err.h
+#include linux/spi/spi.h
+#include linux/module.h
+#include linux/iio/iio.h
+#include linux/regulator/consumer.h
+
+#define MCP_SINGLE_ENDED (1 3)
+#define MCP_START_BIT (1 4)
+
+enum {
+ mcp3204,
+ mcp3208,
+};
+
+struct mcp320x {
+ struct spi_device *spi;
+ struct spi_message msg;
+ struct spi_transfer transfer[2];
+
+ u8 tx_buf;
+ u8 rx_buf[2];
+
+ struct regulator *reg;
+ unsigned int ref_mv;
+
+ struct mutex lock;
+};
+
+static int mcp320x_adc_conversion(struct mcp320x *adc, u8 msg)
+{
+ int ret;
+
+ adc-tx_buf = msg;
+ ret = spi_sync(adc-spi, adc-msg);
+ if (ret 0)
+ return ret;
+
+ return ((adc-rx_buf[0] 0x3f) 6) |
+ (adc-rx_buf[1] 2);
+}
+
+static int mcp320x_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *channel, int *val,
+ int *val2, long mask)
+{
+ struct mcp320x *adc = iio_priv(indio_dev);
+ int ret = -EINVAL;
+
+ mutex_lock(adc-lock);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (channel-differential)
+ ret = mcp320x_adc_conversion(adc,
+ MCP_START_BIT | channel-address);
+ else
+ ret = mcp320x_adc_conversion(adc,
+ MCP_START_BIT | MCP_SINGLE_ENDED |
+ channel-address);
+ if (ret 0)
+ goto out;
+
+ *val = ret;
+ ret = IIO_VAL_INT;
+ break;
+
+ case IIO_CHAN_INFO_SCALE:
+ /* Digital output code = (4096 * Vin) / Vref */
+ ret = regulator_get_voltage(adc-reg);
+ if (ret 0)
+ goto out;
+
+ *val = ret / 1000;
+ *val2 = 12;
+ ret = IIO_VAL_FRACTIONAL_LOG2;
+ break;
+
+ default:
+ break;
+ }
+
+out:
+ mutex_unlock(adc-lock);
+
+ return ret;
+}
+
+#define MCP320X_VOLTAGE_CHANNEL(num) \
+ { \
+ .type = IIO_VOLTAGE,\
+ .indexed = 1, \
+ .channel = (num), \
+ .address = (num), \
+ .info_mask_separate =
Re: [PATCHv3] iio: adc: add driver for MCP3204/08 12-bit ADC
On 05/03/2013 10:55 AM, Oskar Andero wrote:
[...]
+
+struct mcp320x {
+ struct spi_device *spi;
+ struct spi_message msg;
+ struct spi_transfer transfer[2];
+
+ u8 tx_buf;
+ u8 rx_buf[2];
+
+ struct regulator *reg;
+ unsigned int ref_mv;
ref_mv looks unused.
+
+ struct mutex lock;
+};
+
[..]
+static int mcp320x_probe(struct spi_device *spi)
+{
[...]
+
+ ret = regulator_enable(adc-reg);
+ if (ret 0)
+ goto reg_free;
You shouldn't disable the regulator if enabling it failed.
+
+ mutex_init(adc-lock);
+
+ ret = iio_device_register(indio_dev);
+ if (ret 0)
+ goto reg_free;
+
+ return 0;
+
+reg_free:
+ regulator_disable(adc-reg);
+ regulator_put(adc-reg);
+iio_free:
+ iio_device_free(indio_dev);
+
+ return ret;
+}
[...]
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
