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authorLinus Torvalds <torvalds@linux-foundation.org>2014-12-16 03:06:13 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2014-12-16 03:06:13 +0100
commitdab363f938a53ddaee60bfecc1aebdbb3d3af5f0 (patch)
treeccdb11a6e6191ba71fbc7716714c47b79172070d /drivers/iio/adc/mcp320x.c
parentMerge tag 'firewire-updates' of git://git.kernel.org/pub/scm/linux/kernel/git... (diff)
parentStaging: slicoss: Fix long line issues in slicoss.c (diff)
downloadlinux-dab363f938a53ddaee60bfecc1aebdbb3d3af5f0.tar.xz
linux-dab363f938a53ddaee60bfecc1aebdbb3d3af5f0.zip
Merge tag 'staging-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver updates from Greg KH: "Here's the big staging tree pull request for 3.19-rc1. We continued to delete more lines than were added, always a good thing, but not at a huge rate this release, only about 70k lines removed overall mostly from removing the horrid bcm driver. Lots of normal staging driver cleanups and fixes all over the place, well over a thousand of them, the shortlog shows all the horrid details. The "contentious" thing here is the movement of the Android binder code out of staging into the "real" part of the kernel. This is code that has been stable for a few years now and is working as-is in the tens of millions of devices with no issues. Yes, the code is horrid, and the userspace api leaves a lot to be desired, but it's not going to change due to legacy issues that we have no control over. Because so many devices and companies rely on this, and the code is stable, might as well promote it out of staging. This was all discussed at the Linux Plumbers conference, and everyone participating agreed that this was the best way forward. There is work happening to replace the binder code with something new that is happening right now, but I don't expect to see the results of that work for another year at the earliest. If that ever happens, and Android switches over to it, I'll gladly remove this version. As for maintainers, I'll be glad to maintain this code, I've been doing it for the past few years with no problems. I'll send a MAINTAINERS entry for it before 3.19-final is out, still need to talk to the Google developers about if they are willing to help with it or not, last I checked they were, which was good. All of these patches have been in linux-next for a while with no reported issues" * tag 'staging-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1382 commits) Staging: slicoss: Fix long line issues in slicoss.c staging: rtl8712: remove unnecessary else after return staging: comedi: change some printk calls to pr_err staging: rtl8723au: hal: Removed the extra semicolon lustre: Deletion of unnecessary checks before three function calls staging: lustre: fix sparse warnings: static function declaration staging: lustre: fixed sparse warnings related to static declarations staging: unisys: remove duplicate header staging: unisys: remove unneeded structure staging: ft1000 : replace __attribute ((__packed__) with __packed drivers: staging: rtl8192e: Include "asm/unaligned.h" instead of "access_ok.h" in "rtl819x_BAProc.c" Drivers:staging:rtl8192e: Fixed checkpatch warning Drivers:staging:clocking-wizard: Added a newline staging: clocking-wizard: check for a valid clk_name pointer staging: rtl8723au: Hal_InitPGData() avoid unnecessary typecasts staging: rtl8723au: _DisableAnalog(): Avoid zero-init variables unnecessarily staging: rtl8723au: Remove unnecessary wrapper _ResetDigitalProcedure1() staging: rtl8723au: _ResetDigitalProcedure1_92C() reduce code obfuscation staging: rtl8723au: Remove unnecessary wrapper _DisableRFAFEAndResetBB() staging: rtl8723au: _DisableRFAFEAndResetBB8192C(): Reduce code obfuscation ...
Diffstat (limited to 'drivers/iio/adc/mcp320x.c')
-rw-r--r--drivers/iio/adc/mcp320x.c222
1 files changed, 187 insertions, 35 deletions
diff --git a/drivers/iio/adc/mcp320x.c b/drivers/iio/adc/mcp320x.c
index 28a086e48776..efbfd12a4bfd 100644
--- a/drivers/iio/adc/mcp320x.c
+++ b/drivers/iio/adc/mcp320x.c
@@ -1,9 +1,30 @@
/*
* Copyright (C) 2013 Oskar Andero <oskar.andero@gmail.com>
+ * Copyright (C) 2014 Rose Technology
+ * Allan Bendorff Jensen <abj@rosetechnology.dk>
+ * Soren Andersen <san@rosetechnology.dk>
+ *
+ * Driver for following ADC chips from Microchip Technology's:
+ * 10 Bit converter
+ * MCP3001
+ * MCP3002
+ * MCP3004
+ * MCP3008
+ * ------------
+ * 12 bit converter
+ * MCP3201
+ * MCP3202
+ * MCP3204
+ * MCP3208
+ * ------------
*
- * Driver for Microchip Technology's MCP3204 and MCP3208 ADC chips.
* Datasheet can be found here:
- * http://ww1.microchip.com/downloads/en/devicedoc/21298c.pdf
+ * http://ww1.microchip.com/downloads/en/DeviceDoc/21293C.pdf mcp3001
+ * http://ww1.microchip.com/downloads/en/DeviceDoc/21294E.pdf mcp3002
+ * http://ww1.microchip.com/downloads/en/DeviceDoc/21295d.pdf mcp3004/08
+ * 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
*
* 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
@@ -11,19 +32,29 @@
*/
#include <linux/err.h>
+#include <linux/delay.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 {
+ mcp3001,
+ mcp3002,
+ mcp3004,
+ mcp3008,
+ mcp3201,
+ mcp3202,
mcp3204,
mcp3208,
};
+struct mcp320x_chip_info {
+ const struct iio_chan_spec *channels;
+ unsigned int num_channels;
+ unsigned int resolution;
+};
+
struct mcp320x {
struct spi_device *spi;
struct spi_message msg;
@@ -34,19 +65,69 @@ struct mcp320x {
struct regulator *reg;
struct mutex lock;
+ const struct mcp320x_chip_info *chip_info;
};
-static int mcp320x_adc_conversion(struct mcp320x *adc, u8 msg)
+static int mcp320x_channel_to_tx_data(int device_index,
+ const unsigned int channel, bool differential)
+{
+ int start_bit = 1;
+
+ switch (device_index) {
+ case mcp3001:
+ case mcp3201:
+ return 0;
+ case mcp3002:
+ case mcp3202:
+ return ((start_bit << 4) | (!differential << 3) |
+ (channel << 2));
+ case mcp3004:
+ case mcp3204:
+ case mcp3008:
+ case mcp3208:
+ return ((start_bit << 6) | (!differential << 5) |
+ (channel << 2));
+ default:
+ return -EINVAL;
+ }
+}
+
+static int mcp320x_adc_conversion(struct mcp320x *adc, u8 channel,
+ bool differential, int device_index)
{
int ret;
- adc->tx_buf = msg;
- ret = spi_sync(adc->spi, &adc->msg);
- if (ret < 0)
- return ret;
+ adc->rx_buf[0] = 0;
+ adc->rx_buf[1] = 0;
+ adc->tx_buf = mcp320x_channel_to_tx_data(device_index,
+ channel, differential);
+
+ if (device_index != mcp3001 && device_index != mcp3201) {
+ ret = spi_sync(adc->spi, &adc->msg);
+ if (ret < 0)
+ return ret;
+ } else {
+ ret = spi_read(adc->spi, &adc->rx_buf, sizeof(adc->rx_buf));
+ if (ret < 0)
+ return ret;
+ }
- return ((adc->rx_buf[0] & 0x3f) << 6) |
- (adc->rx_buf[1] >> 2);
+ switch (device_index) {
+ case mcp3001:
+ return (adc->rx_buf[0] << 5 | adc->rx_buf[1] >> 3);
+ case mcp3002:
+ case mcp3004:
+ case mcp3008:
+ return (adc->rx_buf[0] << 2 | adc->rx_buf[1] >> 6);
+ case mcp3201:
+ return (adc->rx_buf[0] << 7 | adc->rx_buf[1] >> 1);
+ case mcp3202:
+ case mcp3204:
+ case mcp3208:
+ return (adc->rx_buf[0] << 4 | adc->rx_buf[1] >> 4);
+ default:
+ return -EINVAL;
+ }
}
static int mcp320x_read_raw(struct iio_dev *indio_dev,
@@ -55,18 +136,17 @@ static int mcp320x_read_raw(struct iio_dev *indio_dev,
{
struct mcp320x *adc = iio_priv(indio_dev);
int ret = -EINVAL;
+ int device_index = 0;
mutex_lock(&adc->lock);
+ device_index = spi_get_device_id(adc->spi)->driver_data;
+
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);
+ ret = mcp320x_adc_conversion(adc, channel->address,
+ channel->differential, device_index);
+
if (ret < 0)
goto out;
@@ -75,18 +155,15 @@ static int mcp320x_read_raw(struct iio_dev *indio_dev,
break;
case IIO_CHAN_INFO_SCALE:
- /* Digital output code = (4096 * Vin) / Vref */
ret = regulator_get_voltage(adc->reg);
if (ret < 0)
goto out;
+ /* convert regulator output voltage to mV */
*val = ret / 1000;
- *val2 = 12;
+ *val2 = adc->chip_info->resolution;
ret = IIO_VAL_FRACTIONAL_LOG2;
break;
-
- default:
- break;
}
out:
@@ -117,6 +194,16 @@ out:
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \
}
+static const struct iio_chan_spec mcp3201_channels[] = {
+ MCP320X_VOLTAGE_CHANNEL_DIFF(0),
+};
+
+static const struct iio_chan_spec mcp3202_channels[] = {
+ MCP320X_VOLTAGE_CHANNEL(0),
+ MCP320X_VOLTAGE_CHANNEL(1),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(0),
+};
+
static const struct iio_chan_spec mcp3204_channels[] = {
MCP320X_VOLTAGE_CHANNEL(0),
MCP320X_VOLTAGE_CHANNEL(1),
@@ -146,19 +233,46 @@ static const struct iio_info mcp320x_info = {
.driver_module = THIS_MODULE,
};
-struct mcp3208_chip_info {
- const struct iio_chan_spec *channels;
- unsigned int num_channels;
-};
-
-static const struct mcp3208_chip_info mcp3208_chip_infos[] = {
+static const struct mcp320x_chip_info mcp320x_chip_infos[] = {
+ [mcp3001] = {
+ .channels = mcp3201_channels,
+ .num_channels = ARRAY_SIZE(mcp3201_channels),
+ .resolution = 10
+ },
+ [mcp3002] = {
+ .channels = mcp3202_channels,
+ .num_channels = ARRAY_SIZE(mcp3202_channels),
+ .resolution = 10
+ },
+ [mcp3004] = {
+ .channels = mcp3204_channels,
+ .num_channels = ARRAY_SIZE(mcp3204_channels),
+ .resolution = 10
+ },
+ [mcp3008] = {
+ .channels = mcp3208_channels,
+ .num_channels = ARRAY_SIZE(mcp3208_channels),
+ .resolution = 10
+ },
+ [mcp3201] = {
+ .channels = mcp3201_channels,
+ .num_channels = ARRAY_SIZE(mcp3201_channels),
+ .resolution = 12
+ },
+ [mcp3202] = {
+ .channels = mcp3202_channels,
+ .num_channels = ARRAY_SIZE(mcp3202_channels),
+ .resolution = 12
+ },
[mcp3204] = {
.channels = mcp3204_channels,
- .num_channels = ARRAY_SIZE(mcp3204_channels)
+ .num_channels = ARRAY_SIZE(mcp3204_channels),
+ .resolution = 12
},
[mcp3208] = {
.channels = mcp3208_channels,
- .num_channels = ARRAY_SIZE(mcp3208_channels)
+ .num_channels = ARRAY_SIZE(mcp3208_channels),
+ .resolution = 12
},
};
@@ -166,7 +280,7 @@ static int mcp320x_probe(struct spi_device *spi)
{
struct iio_dev *indio_dev;
struct mcp320x *adc;
- const struct mcp3208_chip_info *chip_info;
+ const struct mcp320x_chip_info *chip_info;
int ret;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc));
@@ -181,7 +295,7 @@ static int mcp320x_probe(struct spi_device *spi)
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &mcp320x_info;
- chip_info = &mcp3208_chip_infos[spi_get_device_id(spi)->driver_data];
+ chip_info = &mcp320x_chip_infos[spi_get_device_id(spi)->driver_data];
indio_dev->channels = chip_info->channels;
indio_dev->num_channels = chip_info->num_channels;
@@ -226,7 +340,45 @@ static int mcp320x_remove(struct spi_device *spi)
return 0;
}
+#if defined(CONFIG_OF)
+static const struct of_device_id mcp320x_dt_ids[] = {
+ {
+ .compatible = "mcp3001",
+ .data = &mcp320x_chip_infos[mcp3001],
+ }, {
+ .compatible = "mcp3002",
+ .data = &mcp320x_chip_infos[mcp3002],
+ }, {
+ .compatible = "mcp3004",
+ .data = &mcp320x_chip_infos[mcp3004],
+ }, {
+ .compatible = "mcp3008",
+ .data = &mcp320x_chip_infos[mcp3008],
+ }, {
+ .compatible = "mcp3201",
+ .data = &mcp320x_chip_infos[mcp3201],
+ }, {
+ .compatible = "mcp3202",
+ .data = &mcp320x_chip_infos[mcp3202],
+ }, {
+ .compatible = "mcp3204",
+ .data = &mcp320x_chip_infos[mcp3204],
+ }, {
+ .compatible = "mcp3208",
+ .data = &mcp320x_chip_infos[mcp3208],
+ }, {
+ }
+};
+MODULE_DEVICE_TABLE(of, mcp320x_dt_ids);
+#endif
+
static const struct spi_device_id mcp320x_id[] = {
+ { "mcp3001", mcp3001 },
+ { "mcp3002", mcp3002 },
+ { "mcp3004", mcp3004 },
+ { "mcp3008", mcp3008 },
+ { "mcp3201", mcp3201 },
+ { "mcp3202", mcp3202 },
{ "mcp3204", mcp3204 },
{ "mcp3208", mcp3208 },
{ }
@@ -245,5 +397,5 @@ static struct spi_driver mcp320x_driver = {
module_spi_driver(mcp320x_driver);
MODULE_AUTHOR("Oskar Andero <oskar.andero@gmail.com>");
-MODULE_DESCRIPTION("Microchip Technology MCP3204/08");
+MODULE_DESCRIPTION("Microchip Technology MCP3x01/02/04/08");
MODULE_LICENSE("GPL v2");