bcc0403eb4
The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is ignored (apart from emitting a warning) and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new(), which already returns void. Eventually after all drivers are converted, .remove_new() will be renamed to .remove(). Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/adb9b0aca77d7aa8e54d0a664a4ee290834a60a1.1712732665.git.u.kleine-koenig@pengutronix.de
121 lines
3.1 KiB
C
121 lines
3.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Eurobraille/Iris power off support.
|
|
*
|
|
* Eurobraille's Iris machine is a PC with no APM or ACPI support.
|
|
* It is shutdown by a special I/O sequence which this module provides.
|
|
*
|
|
* Copyright (C) Shérab <Sebastien.Hinderer@ens-lyon.org>
|
|
*/
|
|
|
|
#include <linux/moduleparam.h>
|
|
#include <linux/module.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/pm.h>
|
|
#include <asm/io.h>
|
|
|
|
#define IRIS_GIO_BASE 0x340
|
|
#define IRIS_GIO_INPUT IRIS_GIO_BASE
|
|
#define IRIS_GIO_OUTPUT (IRIS_GIO_BASE + 1)
|
|
#define IRIS_GIO_PULSE 0x80 /* First byte to send */
|
|
#define IRIS_GIO_REST 0x00 /* Second byte to send */
|
|
#define IRIS_GIO_NODEV 0xff /* Likely not an Iris */
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Sébastien Hinderer <Sebastien.Hinderer@ens-lyon.org>");
|
|
MODULE_DESCRIPTION("A power_off handler for Iris devices from EuroBraille");
|
|
|
|
static bool force;
|
|
|
|
module_param(force, bool, 0);
|
|
MODULE_PARM_DESC(force, "Set to one to force poweroff handler installation.");
|
|
|
|
static void (*old_pm_power_off)(void);
|
|
|
|
static void iris_power_off(void)
|
|
{
|
|
outb(IRIS_GIO_PULSE, IRIS_GIO_OUTPUT);
|
|
msleep(850);
|
|
outb(IRIS_GIO_REST, IRIS_GIO_OUTPUT);
|
|
}
|
|
|
|
/*
|
|
* Before installing the power_off handler, try to make sure the OS is
|
|
* running on an Iris. Since Iris does not support DMI, this is done
|
|
* by reading its input port and seeing whether the read value is
|
|
* meaningful.
|
|
*/
|
|
static int iris_probe(struct platform_device *pdev)
|
|
{
|
|
unsigned char status = inb(IRIS_GIO_INPUT);
|
|
if (status == IRIS_GIO_NODEV) {
|
|
printk(KERN_ERR "This machine does not seem to be an Iris. "
|
|
"Power off handler not installed.\n");
|
|
return -ENODEV;
|
|
}
|
|
old_pm_power_off = pm_power_off;
|
|
pm_power_off = &iris_power_off;
|
|
printk(KERN_INFO "Iris power_off handler installed.\n");
|
|
return 0;
|
|
}
|
|
|
|
static void iris_remove(struct platform_device *pdev)
|
|
{
|
|
pm_power_off = old_pm_power_off;
|
|
printk(KERN_INFO "Iris power_off handler uninstalled.\n");
|
|
}
|
|
|
|
static struct platform_driver iris_driver = {
|
|
.driver = {
|
|
.name = "iris",
|
|
},
|
|
.probe = iris_probe,
|
|
.remove_new = iris_remove,
|
|
};
|
|
|
|
static struct resource iris_resources[] = {
|
|
{
|
|
.start = IRIS_GIO_BASE,
|
|
.end = IRIS_GIO_OUTPUT,
|
|
.flags = IORESOURCE_IO,
|
|
.name = "address"
|
|
}
|
|
};
|
|
|
|
static struct platform_device *iris_device;
|
|
|
|
static int iris_init(void)
|
|
{
|
|
int ret;
|
|
if (force != 1) {
|
|
printk(KERN_ERR "The force parameter has not been set to 1."
|
|
" The Iris poweroff handler will not be installed.\n");
|
|
return -ENODEV;
|
|
}
|
|
ret = platform_driver_register(&iris_driver);
|
|
if (ret < 0) {
|
|
printk(KERN_ERR "Failed to register iris platform driver: %d\n",
|
|
ret);
|
|
return ret;
|
|
}
|
|
iris_device = platform_device_register_simple("iris", (-1),
|
|
iris_resources, ARRAY_SIZE(iris_resources));
|
|
if (IS_ERR(iris_device)) {
|
|
printk(KERN_ERR "Failed to register iris platform device\n");
|
|
platform_driver_unregister(&iris_driver);
|
|
return PTR_ERR(iris_device);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void iris_exit(void)
|
|
{
|
|
platform_device_unregister(iris_device);
|
|
platform_driver_unregister(&iris_driver);
|
|
}
|
|
|
|
module_init(iris_init);
|
|
module_exit(iris_exit);
|