linux/drivers/misc/hmc6352.c
Uwe Kleine-König ed5c2f5fd1 i2c: Make remove callback return void
The value returned by an i2c driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)

So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.

Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com>
Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Crt Mori <cmo@melexis.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Marek Behún <kabel@kernel.org> # for leds-turris-omnia
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Machata <petrm@nvidia.com> # for mlxsw
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> # for surface3_power
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> # for bmc150-accel-i2c + kxcjk-1013
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for media/* + staging/media/*
Acked-by: Miguel Ojeda <ojeda@kernel.org> # for auxdisplay/ht16k33 + auxdisplay/lcd2s
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for versaclock5
Reviewed-by: Ajay Gupta <ajayg@nvidia.com> # for ucsi_ccg
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio
Acked-by: Peter Rosin <peda@axentia.se> # for i2c-mux-*, max9860
Acked-by: Adrien Grassein <adrien.grassein@gmail.com> # for lontium-lt8912b
Reviewed-by: Jean Delvare <jdelvare@suse.de> # for hwmon, i2c-core and i2c/muxes
Acked-by: Corey Minyard <cminyard@mvista.com> # for IPMI
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> # for drivers/power
Acked-by: Krzysztof Hałasa <khalasa@piap.pl>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-08-16 12:46:26 +02:00

145 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* hmc6352.c - Honeywell Compass Driver
*
* Copyright (C) 2009 Intel Corp
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/sysfs.h>
#include <linux/nospec.h>
static DEFINE_MUTEX(compass_mutex);
static int compass_command(struct i2c_client *c, u8 cmd)
{
int ret = i2c_master_send(c, &cmd, 1);
if (ret < 0)
dev_warn(&c->dev, "command '%c' failed.\n", cmd);
return ret;
}
static int compass_store(struct device *dev, const char *buf, size_t count,
const char *map)
{
struct i2c_client *c = to_i2c_client(dev);
int ret;
unsigned long val;
ret = kstrtoul(buf, 10, &val);
if (ret)
return ret;
if (val >= strlen(map))
return -EINVAL;
val = array_index_nospec(val, strlen(map));
mutex_lock(&compass_mutex);
ret = compass_command(c, map[val]);
mutex_unlock(&compass_mutex);
if (ret < 0)
return ret;
return count;
}
static ssize_t compass_calibration_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
return compass_store(dev, buf, count, "EC");
}
static ssize_t compass_power_mode_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
return compass_store(dev, buf, count, "SW");
}
static ssize_t compass_heading_data_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
unsigned char i2c_data[2];
int ret;
mutex_lock(&compass_mutex);
ret = compass_command(client, 'A');
if (ret != 1) {
mutex_unlock(&compass_mutex);
return ret;
}
msleep(10); /* sending 'A' cmd we need to wait for 7-10 millisecs */
ret = i2c_master_recv(client, i2c_data, 2);
mutex_unlock(&compass_mutex);
if (ret < 0) {
dev_warn(dev, "i2c read data cmd failed\n");
return ret;
}
ret = (i2c_data[0] << 8) | i2c_data[1];
return sprintf(buf, "%d.%d\n", ret/10, ret%10);
}
static DEVICE_ATTR(heading0_input, S_IRUGO, compass_heading_data_show, NULL);
static DEVICE_ATTR(calibration, S_IWUSR, NULL, compass_calibration_store);
static DEVICE_ATTR(power_state, S_IWUSR, NULL, compass_power_mode_store);
static struct attribute *mid_att_compass[] = {
&dev_attr_heading0_input.attr,
&dev_attr_calibration.attr,
&dev_attr_power_state.attr,
NULL
};
static const struct attribute_group m_compass_gr = {
.name = "hmc6352",
.attrs = mid_att_compass
};
static int hmc6352_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int res;
res = sysfs_create_group(&client->dev.kobj, &m_compass_gr);
if (res) {
dev_err(&client->dev, "device_create_file failed\n");
return res;
}
dev_info(&client->dev, "%s HMC6352 compass chip found\n",
client->name);
return 0;
}
static void hmc6352_remove(struct i2c_client *client)
{
sysfs_remove_group(&client->dev.kobj, &m_compass_gr);
}
static const struct i2c_device_id hmc6352_id[] = {
{ "hmc6352", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, hmc6352_id);
static struct i2c_driver hmc6352_driver = {
.driver = {
.name = "hmc6352",
},
.probe = hmc6352_probe,
.remove = hmc6352_remove,
.id_table = hmc6352_id,
};
module_i2c_driver(hmc6352_driver);
MODULE_AUTHOR("Kalhan Trisal <kalhan.trisal@intel.com");
MODULE_DESCRIPTION("hmc6352 Compass Driver");
MODULE_LICENSE("GPL v2");