iio: adc: mcp320x: Add support for mcp3301

This adds support for Microchip's 13 bit 1 channel AD converter MCP3301

Signed-off-by: Andrea Galbusera <gizero@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/Documentation/devicetree/bindings/iio/adc/mcp320x.txt b/Documentation/devicetree/bindings/iio/adc/mcp320x.txt
index b851843..2a1f3af 100644 (file)
--- a/Documentation/devicetree/bindings/iio/adc/mcp320x.txt
+++ b/Documentation/devicetree/bindings/iio/adc/mcp320x.txt
@@ -18,6 +18,7 @@ Required properties:
                                "mcp3202"
                                "mcp3204"
                                "mcp3208"
+                               "mcp3301"
 
 
 Examples:

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index dace593..2714f04 100644 (file)
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -229,8 +229,8 @@ config MCP320X
        depends on SPI
        help
          Say yes here to build support for Microchip Technology's
-         MCP3001, MCP3002, MCP3004, MCP3008, MCP3201, MCP3202, MCP3204 or
-         MCP3208 analog to digital converter.
+         MCP3001, MCP3002, MCP3004, MCP3008, MCP3201, MCP3202, MCP3204,
+         MCP3208 or MCP3301 analog to digital converter.
 
          This driver can also be built as a module. If so, the module will be
          called mcp320x.

diff --git a/drivers/iio/adc/mcp320x.c b/drivers/iio/adc/mcp320x.c
index 8d9c9b9..72969c8 100644 (file)
--- a/drivers/iio/adc/mcp320x.c
+++ b/drivers/iio/adc/mcp320x.c
@@ -25,6 +25,7 @@
  * http://ww1.microchip.com/downloads/en/DeviceDoc/21290D.pdf  mcp3201
  * http://ww1.microchip.com/downloads/en/DeviceDoc/21034D.pdf  mcp3202
  * http://ww1.microchip.com/downloads/en/DeviceDoc/21298c.pdf  mcp3204/08
+ * http://ww1.microchip.com/downloads/en/DeviceDoc/21700E.pdf  mcp3301
  *
  * 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
@@ -47,6 +48,7 @@ enum {
        mcp3202,
        mcp3204,
        mcp3208,
+       mcp3301,
 };
 
 struct mcp320x_chip_info {
@@ -76,6 +78,7 @@ static int mcp320x_channel_to_tx_data(int device_index,
        switch (device_index) {
        case mcp3001:
        case mcp3201:
+       case mcp3301:
                return 0;
        case mcp3002:
        case mcp3202:
@@ -102,7 +105,7 @@ static int mcp320x_adc_conversion(struct mcp320x *adc, u8 channel,
        adc->tx_buf = mcp320x_channel_to_tx_data(device_index,
                                                channel, differential);
 
-       if (device_index != mcp3001 && device_index != mcp3201) {
+       if (device_index != mcp3001 && device_index != mcp3201 && device_index != mcp3301) {
                ret = spi_sync(adc->spi, &adc->msg);
                if (ret < 0)
                        return ret;
@@ -125,6 +128,8 @@ static int mcp320x_adc_conversion(struct mcp320x *adc, u8 channel,
        case mcp3204:
        case mcp3208:
                return (adc->rx_buf[0] << 4 | adc->rx_buf[1] >> 4);
+       case mcp3301:
+               return sign_extend32((adc->rx_buf[0] & 0x1f) << 8 | adc->rx_buf[1], 12);
        default:
                return -EINVAL;
        }
@@ -274,6 +279,11 @@ static const struct mcp320x_chip_info mcp320x_chip_infos[] = {
                .num_channels = ARRAY_SIZE(mcp3208_channels),
                .resolution = 12
        },
+       [mcp3301] = {
+               .channels = mcp3201_channels,
+               .num_channels = ARRAY_SIZE(mcp3201_channels),
+               .resolution = 13
+       },
 };
 
 static int mcp320x_probe(struct spi_device *spi)
@@ -367,6 +377,9 @@ static const struct of_device_id mcp320x_dt_ids[] = {
                .compatible = "mcp3208",
                .data = &mcp320x_chip_infos[mcp3208],
        }, {
+               .compatible = "mcp3301",
+               .data = &mcp320x_chip_infos[mcp3301],
+       }, {
        }
 };
 MODULE_DEVICE_TABLE(of, mcp320x_dt_ids);
@@ -381,6 +394,7 @@ static const struct spi_device_id mcp320x_id[] = {
        { "mcp3202", mcp3202 },
        { "mcp3204", mcp3204 },
        { "mcp3208", mcp3208 },
+       { "mcp3301", mcp3301 },
        { }
 };
 MODULE_DEVICE_TABLE(spi, mcp320x_id);