linux-stable/drivers/input/keyboard/ipaq-micro-keys.c
Dmitry Torokhov d1212ac94e Input: ipaq-micro-keys - use guard notation when acquiring mutex and spinlock
This makes the code more compact and error handling more robust
by ensuring that locks are released in all code paths when control
leaves critical section.

Link: https://lore.kernel.org/r/20240825051627.2848495-8-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2024-10-03 08:53:14 -07:00

167 lines
3.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
*
* h3600 atmel micro companion support, key subdevice
* based on previous kernel 2.4 version
* Author : Alessandro Gardich <gremlin@gremlin.it>
* Author : Linus Walleij <linus.walleij@linaro.org>
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/pm.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/input.h>
#include <linux/platform_device.h>
#include <linux/mfd/ipaq-micro.h>
struct ipaq_micro_keys {
struct ipaq_micro *micro;
struct input_dev *input;
u16 *codes;
};
static const u16 micro_keycodes[] = {
KEY_RECORD, /* 1: Record button */
KEY_CALENDAR, /* 2: Calendar */
KEY_ADDRESSBOOK, /* 3: Contacts (looks like Outlook) */
KEY_MAIL, /* 4: Envelope (Q on older iPAQs) */
KEY_HOMEPAGE, /* 5: Start (looks like swoopy arrow) */
KEY_UP, /* 6: Up */
KEY_RIGHT, /* 7: Right */
KEY_LEFT, /* 8: Left */
KEY_DOWN, /* 9: Down */
};
static void micro_key_receive(void *data, int len, unsigned char *msg)
{
struct ipaq_micro_keys *keys = data;
int key, down;
down = 0x80 & msg[0];
key = 0x7f & msg[0];
if (key < ARRAY_SIZE(micro_keycodes)) {
input_report_key(keys->input, keys->codes[key], down);
input_sync(keys->input);
}
}
static void micro_key_start(struct ipaq_micro_keys *keys)
{
guard(spinlock)(&keys->micro->lock);
keys->micro->key = micro_key_receive;
keys->micro->key_data = keys;
}
static void micro_key_stop(struct ipaq_micro_keys *keys)
{
guard(spinlock)(&keys->micro->lock);
keys->micro->key = NULL;
keys->micro->key_data = NULL;
}
static int micro_key_open(struct input_dev *input)
{
struct ipaq_micro_keys *keys = input_get_drvdata(input);
micro_key_start(keys);
return 0;
}
static void micro_key_close(struct input_dev *input)
{
struct ipaq_micro_keys *keys = input_get_drvdata(input);
micro_key_stop(keys);
}
static int micro_key_probe(struct platform_device *pdev)
{
struct ipaq_micro_keys *keys;
int error;
int i;
keys = devm_kzalloc(&pdev->dev, sizeof(*keys), GFP_KERNEL);
if (!keys)
return -ENOMEM;
keys->micro = dev_get_drvdata(pdev->dev.parent);
keys->input = devm_input_allocate_device(&pdev->dev);
if (!keys->input)
return -ENOMEM;
keys->input->keycodesize = sizeof(micro_keycodes[0]);
keys->input->keycodemax = ARRAY_SIZE(micro_keycodes);
keys->codes = devm_kmemdup(&pdev->dev, micro_keycodes,
keys->input->keycodesize * keys->input->keycodemax,
GFP_KERNEL);
if (!keys->codes)
return -ENOMEM;
keys->input->keycode = keys->codes;
__set_bit(EV_KEY, keys->input->evbit);
for (i = 0; i < ARRAY_SIZE(micro_keycodes); i++)
__set_bit(micro_keycodes[i], keys->input->keybit);
keys->input->name = "h3600 micro keys";
keys->input->open = micro_key_open;
keys->input->close = micro_key_close;
input_set_drvdata(keys->input, keys);
error = input_register_device(keys->input);
if (error)
return error;
platform_set_drvdata(pdev, keys);
return 0;
}
static int micro_key_suspend(struct device *dev)
{
struct ipaq_micro_keys *keys = dev_get_drvdata(dev);
micro_key_stop(keys);
return 0;
}
static int micro_key_resume(struct device *dev)
{
struct ipaq_micro_keys *keys = dev_get_drvdata(dev);
struct input_dev *input = keys->input;
guard(mutex)(&input->mutex);
if (input_device_enabled(input))
micro_key_start(keys);
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(micro_key_dev_pm_ops,
micro_key_suspend, micro_key_resume);
static struct platform_driver micro_key_device_driver = {
.driver = {
.name = "ipaq-micro-keys",
.pm = pm_sleep_ptr(&micro_key_dev_pm_ops),
},
.probe = micro_key_probe,
};
module_platform_driver(micro_key_device_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("driver for iPAQ Atmel micro keys");
MODULE_ALIAS("platform:ipaq-micro-keys");