mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-29 23:53:32 +00:00
673afe4661
Many hwmon drivers don't use the id information provided by the old
i2c probe function, and the remainder can easily be adapted to the new
form ("probe_new") by calling i2c_match_id explicitly.
This avoids scanning the identifier tables during probes.
Drivers which didn't use the id are converted as-is; drivers which did
are modified to call i2c_match_id() with the same level of
error-handling (if any) as before.
This patch wraps up the transition for hwmon, with four stragglers not
included in the previous large patch.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200821160354.594715-1-steve@sk2.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
218 lines
6.3 KiB
C
218 lines
6.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles
|
|
* (C) 2007 EADS Astrium
|
|
*
|
|
* This driver is based on the lm75 and other lm_sensors/hwmon drivers
|
|
*
|
|
* Written by Steve Hardy <shardy@redhat.com>
|
|
*
|
|
* ADS7830 support, by Guillaume Roguez <guillaume.roguez@savoirfairelinux.com>
|
|
*
|
|
* For further information, see the Documentation/hwmon/ads7828.rst file.
|
|
*/
|
|
|
|
#include <linux/err.h>
|
|
#include <linux/hwmon.h>
|
|
#include <linux/hwmon-sysfs.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/init.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/platform_data/ads7828.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/regulator/consumer.h>
|
|
|
|
/* The ADS7828 registers */
|
|
#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
|
|
#define ADS7828_CMD_PD1 0x04 /* Internal vref OFF && A/D ON */
|
|
#define ADS7828_CMD_PD3 0x0C /* Internal vref ON && A/D ON */
|
|
#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
|
|
#define ADS7828_EXT_VREF_MV_MIN 50 /* External vref min value 0.05V */
|
|
#define ADS7828_EXT_VREF_MV_MAX 5250 /* External vref max value 5.25V */
|
|
|
|
/* List of supported devices */
|
|
enum ads7828_chips { ads7828, ads7830 };
|
|
|
|
/* Client specific data */
|
|
struct ads7828_data {
|
|
struct regmap *regmap;
|
|
u8 cmd_byte; /* Command byte without channel bits */
|
|
unsigned int lsb_resol; /* Resolution of the ADC sample LSB */
|
|
};
|
|
|
|
/* Command byte C2,C1,C0 - see datasheet */
|
|
static inline u8 ads7828_cmd_byte(u8 cmd, int ch)
|
|
{
|
|
return cmd | (((ch >> 1) | (ch & 0x01) << 2) << 4);
|
|
}
|
|
|
|
/* sysfs callback function */
|
|
static ssize_t ads7828_in_show(struct device *dev,
|
|
struct device_attribute *da, char *buf)
|
|
{
|
|
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
|
|
struct ads7828_data *data = dev_get_drvdata(dev);
|
|
u8 cmd = ads7828_cmd_byte(data->cmd_byte, attr->index);
|
|
unsigned int regval;
|
|
int err;
|
|
|
|
err = regmap_read(data->regmap, cmd, ®val);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
return sprintf(buf, "%d\n",
|
|
DIV_ROUND_CLOSEST(regval * data->lsb_resol, 1000));
|
|
}
|
|
|
|
static SENSOR_DEVICE_ATTR_RO(in0_input, ads7828_in, 0);
|
|
static SENSOR_DEVICE_ATTR_RO(in1_input, ads7828_in, 1);
|
|
static SENSOR_DEVICE_ATTR_RO(in2_input, ads7828_in, 2);
|
|
static SENSOR_DEVICE_ATTR_RO(in3_input, ads7828_in, 3);
|
|
static SENSOR_DEVICE_ATTR_RO(in4_input, ads7828_in, 4);
|
|
static SENSOR_DEVICE_ATTR_RO(in5_input, ads7828_in, 5);
|
|
static SENSOR_DEVICE_ATTR_RO(in6_input, ads7828_in, 6);
|
|
static SENSOR_DEVICE_ATTR_RO(in7_input, ads7828_in, 7);
|
|
|
|
static struct attribute *ads7828_attrs[] = {
|
|
&sensor_dev_attr_in0_input.dev_attr.attr,
|
|
&sensor_dev_attr_in1_input.dev_attr.attr,
|
|
&sensor_dev_attr_in2_input.dev_attr.attr,
|
|
&sensor_dev_attr_in3_input.dev_attr.attr,
|
|
&sensor_dev_attr_in4_input.dev_attr.attr,
|
|
&sensor_dev_attr_in5_input.dev_attr.attr,
|
|
&sensor_dev_attr_in6_input.dev_attr.attr,
|
|
&sensor_dev_attr_in7_input.dev_attr.attr,
|
|
NULL
|
|
};
|
|
|
|
ATTRIBUTE_GROUPS(ads7828);
|
|
|
|
static const struct regmap_config ads2828_regmap_config = {
|
|
.reg_bits = 8,
|
|
.val_bits = 16,
|
|
};
|
|
|
|
static const struct regmap_config ads2830_regmap_config = {
|
|
.reg_bits = 8,
|
|
.val_bits = 8,
|
|
};
|
|
|
|
static const struct i2c_device_id ads7828_device_ids[];
|
|
|
|
static int ads7828_probe(struct i2c_client *client)
|
|
{
|
|
struct device *dev = &client->dev;
|
|
struct ads7828_platform_data *pdata = dev_get_platdata(dev);
|
|
struct ads7828_data *data;
|
|
struct device *hwmon_dev;
|
|
unsigned int vref_mv = ADS7828_INT_VREF_MV;
|
|
unsigned int vref_uv;
|
|
bool diff_input = false;
|
|
bool ext_vref = false;
|
|
unsigned int regval;
|
|
enum ads7828_chips chip;
|
|
struct regulator *reg;
|
|
|
|
data = devm_kzalloc(dev, sizeof(struct ads7828_data), GFP_KERNEL);
|
|
if (!data)
|
|
return -ENOMEM;
|
|
|
|
if (pdata) {
|
|
diff_input = pdata->diff_input;
|
|
ext_vref = pdata->ext_vref;
|
|
if (ext_vref && pdata->vref_mv)
|
|
vref_mv = pdata->vref_mv;
|
|
} else if (dev->of_node) {
|
|
diff_input = of_property_read_bool(dev->of_node,
|
|
"ti,differential-input");
|
|
reg = devm_regulator_get_optional(dev, "vref");
|
|
if (!IS_ERR(reg)) {
|
|
vref_uv = regulator_get_voltage(reg);
|
|
vref_mv = DIV_ROUND_CLOSEST(vref_uv, 1000);
|
|
if (vref_mv < ADS7828_EXT_VREF_MV_MIN ||
|
|
vref_mv > ADS7828_EXT_VREF_MV_MAX)
|
|
return -EINVAL;
|
|
ext_vref = true;
|
|
}
|
|
}
|
|
|
|
if (client->dev.of_node)
|
|
chip = (enum ads7828_chips)
|
|
of_device_get_match_data(&client->dev);
|
|
else
|
|
chip = i2c_match_id(ads7828_device_ids, client)->driver_data;
|
|
|
|
/* Bound Vref with min/max values */
|
|
vref_mv = clamp_val(vref_mv, ADS7828_EXT_VREF_MV_MIN,
|
|
ADS7828_EXT_VREF_MV_MAX);
|
|
|
|
/* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
|
|
if (chip == ads7828) {
|
|
data->lsb_resol = DIV_ROUND_CLOSEST(vref_mv * 1000, 4096);
|
|
data->regmap = devm_regmap_init_i2c(client,
|
|
&ads2828_regmap_config);
|
|
} else {
|
|
data->lsb_resol = DIV_ROUND_CLOSEST(vref_mv * 1000, 256);
|
|
data->regmap = devm_regmap_init_i2c(client,
|
|
&ads2830_regmap_config);
|
|
}
|
|
|
|
if (IS_ERR(data->regmap))
|
|
return PTR_ERR(data->regmap);
|
|
|
|
data->cmd_byte = ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
|
|
if (!diff_input)
|
|
data->cmd_byte |= ADS7828_CMD_SD_SE;
|
|
|
|
/*
|
|
* Datasheet specifies internal reference voltage is disabled by
|
|
* default. The internal reference voltage needs to be enabled and
|
|
* voltage needs to settle before getting valid ADC data. So perform a
|
|
* dummy read to enable the internal reference voltage.
|
|
*/
|
|
if (!ext_vref)
|
|
regmap_read(data->regmap, data->cmd_byte, ®val);
|
|
|
|
hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
|
|
data,
|
|
ads7828_groups);
|
|
return PTR_ERR_OR_ZERO(hwmon_dev);
|
|
}
|
|
|
|
static const struct i2c_device_id ads7828_device_ids[] = {
|
|
{ "ads7828", ads7828 },
|
|
{ "ads7830", ads7830 },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, ads7828_device_ids);
|
|
|
|
static const struct of_device_id __maybe_unused ads7828_of_match[] = {
|
|
{
|
|
.compatible = "ti,ads7828",
|
|
.data = (void *)ads7828
|
|
},
|
|
{
|
|
.compatible = "ti,ads7830",
|
|
.data = (void *)ads7830
|
|
},
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(of, ads7828_of_match);
|
|
|
|
static struct i2c_driver ads7828_driver = {
|
|
.driver = {
|
|
.name = "ads7828",
|
|
.of_match_table = of_match_ptr(ads7828_of_match),
|
|
},
|
|
|
|
.id_table = ads7828_device_ids,
|
|
.probe_new = ads7828_probe,
|
|
};
|
|
|
|
module_i2c_driver(ads7828_driver);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Steve Hardy <shardy@redhat.com>");
|
|
MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles");
|