* Re: [PATCH v3] iio: add support of the max5821
[not found] <1406324581-6958-1-git-send-email-tremyfr@yahoo.fr>
@ 2014-07-27 13:55 ` Jonathan Cameron
0 siblings, 0 replies; only message in thread
From: Jonathan Cameron @ 2014-07-27 13:55 UTC (permalink / raw)
To: Philippe Reynes, linux-iio
Cc: linux-kernel, armadeus-forum, devicetree, julien.boibessot,
pmeerw, borneo.antonio
On 25/07/14 22:43, Philippe Reynes wrote:
> Signed-off-by: Philippe Reynes <tremyfr@yahoo.fr>
Applied to the togreg branch of iio.git. Note this will be initially pushed
out as testing to let the autobuilders play with it.
Thanks,
Jonathan
> ---
> .../devicetree/bindings/iio/dac/max5821.txt | 14 +
> drivers/iio/dac/Kconfig | 8 +
> drivers/iio/dac/Makefile | 1 +
> drivers/iio/dac/max5821.c | 405 ++++++++++++++++++++
> 4 files changed, 428 insertions(+), 0 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/iio/dac/max5821.txt
> create mode 100644 drivers/iio/dac/max5821.c
>
> Changelog:
> v3: (thanks Jonathan Cameron for the feedback)
> - use iio_device_register
> v2: (thanks Peter Meerwald, Antonio Borneo and Jonathan Cameron for the feedback)
> - use devm_iio_device_register
> - use regulator
> - add locking when reading a register
> - use array instead of switch for dac command
> - use ARRAY_SIZE instead of hardcode num of channels
> - set name
> - some others little fix
> diff --git a/Documentation/devicetree/bindings/iio/dac/max5821.txt b/Documentation/devicetree/bindings/iio/dac/max5821.txt
> new file mode 100644
> index 0000000..54276ce
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/dac/max5821.txt
> @@ -0,0 +1,14 @@
> +Maxim max5821 DAC device driver
> +
> +Required properties:
> + - compatible: Must be "maxim,max5821"
> + - reg: Should contain the DAC I2C address
> + - vref-supply: Phandle to the vref power supply
> +
> +Example:
> +
> + max5821@38 {
> + compatible = "maxim,max5821";
> + reg = <0x38>;
> + vref-supply = <®_max5821>;
> + };
> diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
> index f378ca8..fd14a72 100644
> --- a/drivers/iio/dac/Kconfig
> +++ b/drivers/iio/dac/Kconfig
> @@ -152,6 +152,14 @@ config MAX517
> This driver can also be built as a module. If so, the module
> will be called max517.
>
> +config MAX5821
> + tristate "Maxim MAX5821 DAC driver"
> + depends on I2C
> + depends on OF
> + help
> + Say yes here to build support for Maxim MAX5821
> + 10 bits DAC.
> +
> config MCP4725
> tristate "MCP4725 DAC driver"
> depends on I2C
> diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile
> index bb84ad6..82545c0 100644
> --- a/drivers/iio/dac/Makefile
> +++ b/drivers/iio/dac/Makefile
> @@ -17,4 +17,5 @@ obj-$(CONFIG_AD5791) += ad5791.o
> obj-$(CONFIG_AD5686) += ad5686.o
> obj-$(CONFIG_AD7303) += ad7303.o
> obj-$(CONFIG_MAX517) += max517.o
> +obj-$(CONFIG_MAX5821) += max5821.o
> obj-$(CONFIG_MCP4725) += mcp4725.o
> diff --git a/drivers/iio/dac/max5821.c b/drivers/iio/dac/max5821.c
> new file mode 100644
> index 0000000..6e91449
> --- /dev/null
> +++ b/drivers/iio/dac/max5821.c
> @@ -0,0 +1,405 @@
> + /*
> + * iio/dac/max5821.c
> + * Copyright (C) 2014 Philippe Reynes
> + *
> + * 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/kernel.h>
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +#include <linux/iio/iio.h>
> +#include <linux/regulator/consumer.h>
> +
> +#define MAX5821_MAX_DAC_CHANNELS 2
> +
> +/* command bytes */
> +#define MAX5821_LOAD_DAC_A_IN_REG_B 0x00
> +#define MAX5821_LOAD_DAC_B_IN_REG_A 0x10
> +#define MAX5821_EXTENDED_COMMAND_MODE 0xf0
> +#define MAX5821_READ_DAC_A_COMMAND 0xf1
> +#define MAX5821_READ_DAC_B_COMMAND 0xf2
> +
> +#define MAX5821_EXTENDED_POWER_UP 0x00
> +#define MAX5821_EXTENDED_POWER_DOWN_MODE0 0x01
> +#define MAX5821_EXTENDED_POWER_DOWN_MODE1 0x02
> +#define MAX5821_EXTENDED_POWER_DOWN_MODE2 0x03
> +#define MAX5821_EXTENDED_DAC_A 0x04
> +#define MAX5821_EXTENDED_DAC_B 0x08
> +
> +enum max5821_device_ids {
> + ID_MAX5821,
> +};
> +
> +struct max5821_data {
> + struct i2c_client *client;
> + struct regulator *vref_reg;
> + unsigned short vref_mv;
> + bool powerdown[MAX5821_MAX_DAC_CHANNELS];
> + u8 powerdown_mode[MAX5821_MAX_DAC_CHANNELS];
> + struct mutex lock;
> +};
> +
> +static const char * const max5821_powerdown_modes[] = {
> + "three_state",
> + "1kohm_to_gnd",
> + "100kohm_to_gnd",
> +};
> +
> +enum {
> + MAX5821_THREE_STATE,
> + MAX5821_1KOHM_TO_GND,
> + MAX5821_100KOHM_TO_GND
> +};
> +
> +static int max5821_get_powerdown_mode(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan)
> +{
> + struct max5821_data *st = iio_priv(indio_dev);
> +
> + return st->powerdown_mode[chan->channel];
> +}
> +
> +static int max5821_set_powerdown_mode(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan,
> + unsigned int mode)
> +{
> + struct max5821_data *st = iio_priv(indio_dev);
> +
> + st->powerdown_mode[chan->channel] = mode;
> +
> + return 0;
> +}
> +
> +static const struct iio_enum max5821_powerdown_mode_enum = {
> + .items = max5821_powerdown_modes,
> + .num_items = ARRAY_SIZE(max5821_powerdown_modes),
> + .get = max5821_get_powerdown_mode,
> + .set = max5821_set_powerdown_mode,
> +};
> +
> +static ssize_t max5821_read_dac_powerdown(struct iio_dev *indio_dev,
> + uintptr_t private,
> + const struct iio_chan_spec *chan,
> + char *buf)
> +{
> + struct max5821_data *st = iio_priv(indio_dev);
> +
> + return sprintf(buf, "%d\n", st->powerdown[chan->channel]);
> +}
> +
> +static int max5821_sync_powerdown_mode(struct max5821_data *data,
> + const struct iio_chan_spec *chan)
> +{
> + u8 outbuf[2];
> +
> + outbuf[0] = MAX5821_EXTENDED_COMMAND_MODE;
> +
> + if (chan->channel == 0)
> + outbuf[1] = MAX5821_EXTENDED_DAC_A;
> + else
> + outbuf[1] = MAX5821_EXTENDED_DAC_B;
> +
> + if (data->powerdown[chan->channel])
> + outbuf[1] |= data->powerdown_mode[chan->channel] + 1;
> + else
> + outbuf[1] |= MAX5821_EXTENDED_POWER_UP;
> +
> + return i2c_master_send(data->client, outbuf, 2);
> +}
> +
> +static ssize_t max5821_write_dac_powerdown(struct iio_dev *indio_dev,
> + uintptr_t private,
> + const struct iio_chan_spec *chan,
> + const char *buf, size_t len)
> +{
> + struct max5821_data *data = iio_priv(indio_dev);
> + bool powerdown;
> + int ret;
> +
> + ret = strtobool(buf, &powerdown);
> + if (ret)
> + return ret;
> +
> + data->powerdown[chan->channel] = powerdown;
> +
> + ret = max5821_sync_powerdown_mode(data, chan);
> + if (ret < 0)
> + return ret;
> +
> + return len;
> +}
> +
> +static const struct iio_chan_spec_ext_info max5821_ext_info[] = {
> + {
> + .name = "powerdown",
> + .read = max5821_read_dac_powerdown,
> + .write = max5821_write_dac_powerdown,
> + .shared = IIO_SEPARATE,
> + },
> + IIO_ENUM("powerdown_mode", IIO_SEPARATE, &max5821_powerdown_mode_enum),
> + IIO_ENUM_AVAILABLE("powerdown_mode", &max5821_powerdown_mode_enum),
> + { },
> +};
> +
> +#define MAX5821_CHANNEL(chan) { \
> + .type = IIO_VOLTAGE, \
> + .indexed = 1, \
> + .output = 1, \
> + .channel = (chan), \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE), \
> + .ext_info = max5821_ext_info, \
> +}
> +
> +static const struct iio_chan_spec max5821_channels[] = {
> + MAX5821_CHANNEL(0),
> + MAX5821_CHANNEL(1)
> +};
> +
> +static const u8 max5821_read_dac_command[] = {
> + MAX5821_READ_DAC_A_COMMAND,
> + MAX5821_READ_DAC_B_COMMAND
> +};
> +
> +static const u8 max5821_load_dac_command[] = {
> + MAX5821_LOAD_DAC_A_IN_REG_B,
> + MAX5821_LOAD_DAC_B_IN_REG_A
> +};
> +
> +static int max5821_get_value(struct iio_dev *indio_dev,
> + int *val, int channel)
> +{
> + struct max5821_data *data = iio_priv(indio_dev);
> + struct i2c_client *client = data->client;
> + u8 outbuf[1];
> + u8 inbuf[2];
> + int ret;
> +
> + if ((channel != 0) && (channel != 1))
> + return -EINVAL;
> +
> + outbuf[0] = max5821_read_dac_command[channel];
> +
> + mutex_lock(&data->lock);
> +
> + ret = i2c_master_send(client, outbuf, 1);
> + if (ret < 0) {
> + mutex_unlock(&data->lock);
> + return ret;
> + } else if (ret != 1) {
> + mutex_unlock(&data->lock);
> + return -EIO;
> + }
> +
> + ret = i2c_master_recv(client, inbuf, 2);
> + if (ret < 0) {
> + mutex_unlock(&data->lock);
> + return ret;
> + } else if (ret != 2) {
> + mutex_unlock(&data->lock);
> + return -EIO;
> + }
> +
> + mutex_unlock(&data->lock);
> +
> + *val = ((inbuf[0] & 0x0f) << 6) | (inbuf[1] >> 2);
> +
> + return IIO_VAL_INT;
> +}
> +
> +static int max5821_set_value(struct iio_dev *indio_dev,
> + int val, int channel)
> +{
> + struct max5821_data *data = iio_priv(indio_dev);
> + struct i2c_client *client = data->client;
> + u8 outbuf[2];
> + int ret;
> +
> + if ((val < 0) || (val > 1023))
> + return -EINVAL;
> +
> + if ((channel != 0) && (channel != 1))
> + return -EINVAL;
> +
> + outbuf[0] = max5821_load_dac_command[channel];
> + outbuf[0] |= val >> 6;
> + outbuf[1] = (val & 0x3f) << 2;
> +
> + ret = i2c_master_send(client, outbuf, 2);
> + if (ret < 0)
> + return ret;
> + else if (ret != 2)
> + return -EIO;
> + else
> + return 0;
> +}
> +
> +static int max5821_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + struct max5821_data *data = iio_priv(indio_dev);
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + return max5821_get_value(indio_dev, val, chan->channel);
> + case IIO_CHAN_INFO_SCALE:
> + *val = data->vref_mv;
> + *val2 = 10;
> + return IIO_VAL_FRACTIONAL_LOG2;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int max5821_write_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int val, int val2, long mask)
> +{
> + if (val2 != 0)
> + return -EINVAL;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + return max5821_set_value(indio_dev, val, chan->channel);
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int max5821_suspend(struct device *dev)
> +{
> + u8 outbuf[2] = { MAX5821_EXTENDED_COMMAND_MODE,
> + MAX5821_EXTENDED_DAC_A |
> + MAX5821_EXTENDED_DAC_B |
> + MAX5821_EXTENDED_POWER_DOWN_MODE2 };
> +
> + return i2c_master_send(to_i2c_client(dev), outbuf, 2);
> +}
> +
> +static int max5821_resume(struct device *dev)
> +{
> + u8 outbuf[2] = { MAX5821_EXTENDED_COMMAND_MODE,
> + MAX5821_EXTENDED_DAC_A |
> + MAX5821_EXTENDED_DAC_B |
> + MAX5821_EXTENDED_POWER_UP };
> +
> + return i2c_master_send(to_i2c_client(dev), outbuf, 2);
> +}
> +
> +static SIMPLE_DEV_PM_OPS(max5821_pm_ops, max5821_suspend, max5821_resume);
> +#define MAX5821_PM_OPS (&max5821_pm_ops)
> +#else
> +#define MAX5821_PM_OPS NULL
> +#endif /* CONFIG_PM_SLEEP */
> +
> +static const struct iio_info max5821_info = {
> + .read_raw = max5821_read_raw,
> + .write_raw = max5821_write_raw,
> + .driver_module = THIS_MODULE,
> +};
> +
> +static int max5821_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct max5821_data *data;
> + struct iio_dev *indio_dev;
> + u32 tmp;
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> + if (!indio_dev)
> + return -ENOMEM;
> + data = iio_priv(indio_dev);
> + i2c_set_clientdata(client, indio_dev);
> + data->client = client;
> + mutex_init(&data->lock);
> +
> + /* max5821 start in powerdown mode 100Kohm to ground */
> + for (tmp = 0; tmp < MAX5821_MAX_DAC_CHANNELS; tmp++) {
> + data->powerdown[tmp] = true;
> + data->powerdown_mode[tmp] = MAX5821_100KOHM_TO_GND;
> + }
> +
> + data->vref_reg = devm_regulator_get(&client->dev, "vref");
> + if (IS_ERR(data->vref_reg)) {
> + ret = PTR_ERR(data->vref_reg);
> + dev_err(&client->dev,
> + "Failed to get vref regulator: %d\n", ret);
> + goto error_free_reg;
> + }
> +
> + ret = regulator_enable(data->vref_reg);
> + if (ret) {
> + dev_err(&client->dev,
> + "Failed to enable vref regulator: %d\n", ret);
> + goto error_free_reg;
> + }
> +
> + ret = regulator_get_voltage(data->vref_reg);
> + if (ret < 0) {
> + dev_err(&client->dev,
> + "Failed to get voltage on regulator: %d\n", ret);
> + goto error_disable_reg;
> + }
> +
> + data->vref_mv = ret / 1000;
> +
> + indio_dev->name = id->name;
> + indio_dev->dev.parent = &client->dev;
> + indio_dev->num_channels = ARRAY_SIZE(max5821_channels);
> + indio_dev->channels = max5821_channels;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> + indio_dev->info = &max5821_info;
> +
> + return iio_device_register(indio_dev);
> +
> +error_disable_reg:
> + regulator_disable(data->vref_reg);
> +
> +error_free_reg:
> +
> + return ret;
> +}
> +
> +static int max5821_remove(struct i2c_client *client)
> +{
> + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> + struct max5821_data *data = iio_priv(indio_dev);
> +
> + iio_device_unregister(indio_dev);
> + regulator_disable(data->vref_reg);
> +
> + return 0;
> +}
> +
> +static const struct i2c_device_id max5821_id[] = {
> + { "max5821", ID_MAX5821 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, max5821_id);
> +
> +static const struct of_device_id max5821_of_match[] = {
> + { .compatible = "maxim,max5821" },
> + { }
> +};
> +
> +static struct i2c_driver max5821_driver = {
> + .driver = {
> + .name = "max5821",
> + .pm = MAX5821_PM_OPS,
> + .owner = THIS_MODULE,
> + },
> + .probe = max5821_probe,
> + .remove = max5821_remove,
> + .id_table = max5821_id,
> +};
> +module_i2c_driver(max5821_driver);
> +
> +MODULE_AUTHOR("Philippe Reynes <tremyfr@yahoo.fr>");
> +MODULE_DESCRIPTION("MAX5821 DAC");
> +MODULE_LICENSE("GPL v2");
>
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