summaryrefslogtreecommitdiff
path: root/drivers/hwmon/mcp3021.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/hwmon/mcp3021.c')
-rw-r--r--drivers/hwmon/mcp3021.c164
1 files changed, 86 insertions, 78 deletions
diff --git a/drivers/hwmon/mcp3021.c b/drivers/hwmon/mcp3021.c
index eedb32292d6d..bcddf6804d3a 100644
--- a/drivers/hwmon/mcp3021.c
+++ b/drivers/hwmon/mcp3021.c
@@ -1,18 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* mcp3021.c - driver for Microchip MCP3021 and MCP3221
*
* Copyright (C) 2008-2009, 2012 Freescale Semiconductor, Inc.
* Author: Mingkai Hu <Mingkai.hu@freescale.com>
* Reworked by Sven Schuchmann <schuchmann@schleissheimer.de>
+ * DT support added by Clemens Gruber <clemens.gruber@pqgruber.com>
*
- * This driver export the value of analog input voltage to sysfs, the
+ * This driver exports the value of analog input voltage to sysfs, the
* voltage unit is mV. Through the sysfs interface, lm-sensors tool
* can also display the input voltage.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
*/
#include <linux/kernel.h>
@@ -22,23 +19,21 @@
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/device.h>
+#include <linux/of.h>
-/* Vdd info */
-#define MCP3021_VDD_MAX 5500
-#define MCP3021_VDD_MIN 2700
-#define MCP3021_VDD_REF 3300
+/* Vdd / reference voltage in millivolt */
+#define MCP3021_VDD_REF_MAX 5500
+#define MCP3021_VDD_REF_MIN 2700
+#define MCP3021_VDD_REF_DEFAULT 3300
/* output format */
#define MCP3021_SAR_SHIFT 2
#define MCP3021_SAR_MASK 0x3ff
-
#define MCP3021_OUTPUT_RES 10 /* 10-bit resolution */
-#define MCP3021_OUTPUT_SCALE 4
#define MCP3221_SAR_SHIFT 0
#define MCP3221_SAR_MASK 0xfff
#define MCP3221_OUTPUT_RES 12 /* 12-bit resolution */
-#define MCP3221_OUTPUT_SCALE 1
enum chips {
mcp3021,
@@ -49,20 +44,29 @@ enum chips {
* Client data (each client gets its own)
*/
struct mcp3021_data {
- struct device *hwmon_dev;
- u32 vdd; /* device power supply */
+ struct i2c_client *client;
+ u32 vdd; /* supply and reference voltage in millivolt */
u16 sar_shift;
u16 sar_mask;
u8 output_res;
- u8 output_scale;
};
-static int mcp3021_read16(struct i2c_client *client)
+static inline u16 volts_from_reg(struct mcp3021_data *data, u16 val)
{
- struct mcp3021_data *data = i2c_get_clientdata(client);
- int ret;
- u16 reg;
+ return DIV_ROUND_CLOSEST(data->vdd * val, 1 << data->output_res);
+}
+
+static int mcp3021_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct mcp3021_data *data = dev_get_drvdata(dev);
+ struct i2c_client *client = data->client;
__be16 buf;
+ u16 reg;
+ int ret;
+
+ if (type != hwmon_in)
+ return -EOPNOTSUPP;
ret = i2c_master_recv(client, (char *)&buf, 2);
if (ret < 0)
@@ -79,43 +83,45 @@ static int mcp3021_read16(struct i2c_client *client)
*/
reg = (reg >> data->sar_shift) & data->sar_mask;
- return reg;
+ *val = volts_from_reg(data, reg);
+
+ return 0;
}
-static inline u16 volts_from_reg(struct mcp3021_data *data, u16 val)
+static umode_t mcp3021_is_visible(const void *_data,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel)
{
- if (val == 0)
+ if (type != hwmon_in)
return 0;
- val = val * data->output_scale - data->output_scale / 2;
+ if (attr != hwmon_in_input)
+ return 0;
- return val * DIV_ROUND_CLOSEST(data->vdd,
- (1 << data->output_res) * data->output_scale);
+ return 0444;
}
-static ssize_t show_in_input(struct device *dev, struct device_attribute *attr,
- char *buf)
-{
- struct i2c_client *client = to_i2c_client(dev);
- struct mcp3021_data *data = i2c_get_clientdata(client);
- int reg, in_input;
-
- reg = mcp3021_read16(client);
- if (reg < 0)
- return reg;
-
- in_input = volts_from_reg(data, reg);
+static const struct hwmon_channel_info * const mcp3021_info[] = {
+ HWMON_CHANNEL_INFO(in, HWMON_I_INPUT),
+ NULL
+};
- return sprintf(buf, "%d\n", in_input);
-}
+static const struct hwmon_ops mcp3021_hwmon_ops = {
+ .is_visible = mcp3021_is_visible,
+ .read = mcp3021_read,
+};
-static DEVICE_ATTR(in0_input, S_IRUGO, show_in_input, NULL);
+static const struct hwmon_chip_info mcp3021_chip_info = {
+ .ops = &mcp3021_hwmon_ops,
+ .info = mcp3021_info,
+};
-static int mcp3021_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
+static int mcp3021_probe(struct i2c_client *client)
{
- int err;
struct mcp3021_data *data = NULL;
+ struct device_node *np = client->dev.of_node;
+ struct device *hwmon_dev;
+ enum chips type;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
return -ENODEV;
@@ -127,54 +133,47 @@ static int mcp3021_probe(struct i2c_client *client,
i2c_set_clientdata(client, data);
- switch (id->driver_data) {
+ if (np) {
+ if (!of_property_read_u32(np, "reference-voltage-microvolt",
+ &data->vdd))
+ data->vdd /= 1000;
+ else
+ data->vdd = MCP3021_VDD_REF_DEFAULT;
+ } else {
+ u32 *pdata = dev_get_platdata(&client->dev);
+
+ if (pdata)
+ data->vdd = *pdata;
+ else
+ data->vdd = MCP3021_VDD_REF_DEFAULT;
+ }
+
+ type = (uintptr_t)i2c_get_match_data(client);
+ switch (type) {
case mcp3021:
data->sar_shift = MCP3021_SAR_SHIFT;
data->sar_mask = MCP3021_SAR_MASK;
data->output_res = MCP3021_OUTPUT_RES;
- data->output_scale = MCP3021_OUTPUT_SCALE;
break;
case mcp3221:
data->sar_shift = MCP3221_SAR_SHIFT;
data->sar_mask = MCP3221_SAR_MASK;
data->output_res = MCP3221_OUTPUT_RES;
- data->output_scale = MCP3221_OUTPUT_SCALE;
break;
}
- if (client->dev.platform_data) {
- data->vdd = *(u32 *)client->dev.platform_data;
- if (data->vdd > MCP3021_VDD_MAX || data->vdd < MCP3021_VDD_MIN)
- return -EINVAL;
- } else
- data->vdd = MCP3021_VDD_REF;
-
- err = sysfs_create_file(&client->dev.kobj, &dev_attr_in0_input.attr);
- if (err)
- return err;
-
- data->hwmon_dev = hwmon_device_register(&client->dev);
- if (IS_ERR(data->hwmon_dev)) {
- err = PTR_ERR(data->hwmon_dev);
- goto exit_remove;
- }
-
- return 0;
-
-exit_remove:
- sysfs_remove_file(&client->dev.kobj, &dev_attr_in0_input.attr);
- return err;
-}
-
-static int mcp3021_remove(struct i2c_client *client)
-{
- struct mcp3021_data *data = i2c_get_clientdata(client);
+ data->client = client;
- hwmon_device_unregister(data->hwmon_dev);
- sysfs_remove_file(&client->dev.kobj, &dev_attr_in0_input.attr);
+ if (data->vdd > MCP3021_VDD_REF_MAX || data->vdd < MCP3021_VDD_REF_MIN)
+ return -EINVAL;
- return 0;
+ hwmon_dev = devm_hwmon_device_register_with_info(&client->dev,
+ client->name,
+ data,
+ &mcp3021_chip_info,
+ NULL);
+ return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct i2c_device_id mcp3021_id[] = {
@@ -184,12 +183,21 @@ static const struct i2c_device_id mcp3021_id[] = {
};
MODULE_DEVICE_TABLE(i2c, mcp3021_id);
+#ifdef CONFIG_OF
+static const struct of_device_id of_mcp3021_match[] = {
+ { .compatible = "microchip,mcp3021", .data = (void *)mcp3021 },
+ { .compatible = "microchip,mcp3221", .data = (void *)mcp3221 },
+ { }
+};
+MODULE_DEVICE_TABLE(of, of_mcp3021_match);
+#endif
+
static struct i2c_driver mcp3021_driver = {
.driver = {
.name = "mcp3021",
+ .of_match_table = of_match_ptr(of_mcp3021_match),
},
.probe = mcp3021_probe,
- .remove = mcp3021_remove,
.id_table = mcp3021_id,
};
generated by cgit (git 2.34.1) at 2025-12-25 07:30:52 +0000