Commit ee4cd32e authored by Dmitry Torokhov's avatar Dmitry Torokhov Committed by Jean Delvare
Browse files

hwmon: (ams) Fix locking issues 



Use a separate mutex to serialize input device creation/removal,
otheriwse we deadlock if we try to remove input device while it is
being polled. Also do not take ams_info.lock when it is not needed.

Signed-off-by: default avatarDmitry Torokhov <dtor@mail.ru>
Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
parent 0a020022

drivers/hwmon/ams/ams-core.c

+17 −23
Original line number Diff line number Diff line
@@ -223,12 +223,12 @@ int __init ams_init(void) 


void ams_exit(void)

{

	mutex_lock(&ams_info.lock);



	if (ams_info.has_device) {

	/* Remove input device */

	ams_input_exit();



	/* Remove attributes */

	device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);



	/* Shut down implementation */

	ams_info.exit();
@@ -239,9 +239,6 @@ void ams_exit(void) 
	 */

	flush_scheduled_work();



		/* Remove attributes */

		device_remove_file(&ams_info.of_dev->dev, &dev_attr_current);



	/* Remove device */

	of_device_unregister(ams_info.of_dev);
@@ -250,9 +247,6 @@ void ams_exit(void) 
	pmf_unregister_irq_client(&ams_freefall_client);

}



	mutex_unlock(&ams_info.lock);

}



MODULE_AUTHOR("Stelian Pop, Michael Hanselmann");

MODULE_DESCRIPTION("Apple Motion Sensor driver");

MODULE_LICENSE("GPL");

drivers/hwmon/ams/ams-i2c.c

+0 −4
Original line number Diff line number Diff line
@@ -261,8 +261,6 @@ int __init ams_i2c_init(struct device_node *np) 
{

	int result;



	mutex_lock(&ams_info.lock);



	/* Set implementation stuff */

	ams_info.of_node = np;

	ams_info.exit = ams_i2c_exit;
@@ -273,7 +271,5 @@ int __init ams_i2c_init(struct device_node *np) 


	result = i2c_add_driver(&ams_i2c_driver);



	mutex_unlock(&ams_info.lock);



	return result;

}

drivers/hwmon/ams/ams-input.c

+34 −25
Original line number Diff line number Diff line
@@ -27,6 +27,8 @@ static unsigned int invert; 
module_param(invert, bool, S_IWUSR | S_IRUGO);

MODULE_PARM_DESC(invert, "Invert input data on X and Y axis");



static DEFINE_MUTEX(ams_input_mutex);



static void ams_idev_poll(struct input_polled_dev *dev)

{

	struct input_dev *idev = dev->input;
@@ -50,13 +52,11 @@ static void ams_idev_poll(struct input_polled_dev *dev) 
}



/* Call with ams_info.lock held! */

static void ams_input_enable(void)

static int ams_input_enable(void)

{

	struct input_dev *input;

	s8 x, y, z;



	if (ams_info.idev)

		return;

	int error;



	ams_sensors(&x, &y, &z);

	ams_info.xcalib = x;
@@ -65,7 +65,7 @@ static void ams_input_enable(void) 


	ams_info.idev = input_allocate_polled_device();

	if (!ams_info.idev)

		return;

		return -ENOMEM;



	ams_info.idev->poll = ams_idev_poll;

	ams_info.idev->poll_interval = 25;
@@ -84,14 +84,18 @@ static void ams_input_enable(void) 
	set_bit(EV_KEY, input->evbit);

	set_bit(BTN_TOUCH, input->keybit);



	if (input_register_polled_device(ams_info.idev)) {

	error = input_register_polled_device(ams_info.idev);

	if (error) {

		input_free_polled_device(ams_info.idev);

		ams_info.idev = NULL;

		return;

		return error;

	}



	joystick = 1;



	return 0;

}



/* Call with ams_info.lock held! */

static void ams_input_disable(void)

{

	if (ams_info.idev) {
@@ -99,6 +103,8 @@ static void ams_input_disable(void) 
		input_free_polled_device(ams_info.idev);

		ams_info.idev = NULL;

	}



	joystick = 0;

}



static ssize_t ams_input_show_joystick(struct device *dev,
@@ -110,39 +116,42 @@ static ssize_t ams_input_show_joystick(struct device *dev, 
static ssize_t ams_input_store_joystick(struct device *dev,

	struct device_attribute *attr, const char *buf, size_t count)

{

	if (sscanf(buf, "%d\n", &joystick) != 1)

	unsigned long enable;

	int error = 0;



	if (strict_strtoul(buf, 0, &enable) || enable > 1)

		return -EINVAL;



	mutex_lock(&ams_info.lock);

	mutex_lock(&ams_input_mutex);



	if (joystick)

		ams_input_enable();

	if (enable != joystick) {

		if (enable)

			error = ams_input_enable();

		else

			ams_input_disable();

	}



	mutex_unlock(&ams_info.lock);

	mutex_unlock(&ams_input_mutex);



	return count;

	return error ? error : count;

}



static DEVICE_ATTR(joystick, S_IRUGO | S_IWUSR,

	ams_input_show_joystick, ams_input_store_joystick);



/* Call with ams_info.lock held! */

int ams_input_init(void)

{

	int result;



	result = device_create_file(&ams_info.of_dev->dev, &dev_attr_joystick);



	if (!result && joystick)

	if (joystick)

		ams_input_enable();

	return result;



	return device_create_file(&ams_info.of_dev->dev, &dev_attr_joystick);

}



/* Call with ams_info.lock held! */

void ams_input_exit(void)

{

	ams_input_disable();

	device_remove_file(&ams_info.of_dev->dev, &dev_attr_joystick);



	mutex_lock(&ams_input_mutex);

	ams_input_disable();

	mutex_unlock(&ams_input_mutex);

}

drivers/hwmon/ams/ams-pmu.c

+5 −13
Original line number Diff line number Diff line
@@ -149,8 +149,6 @@ int __init ams_pmu_init(struct device_node *np) 
	const u32 *prop;

	int result;



	mutex_lock(&ams_info.lock);



	/* Set implementation stuff */

	ams_info.of_node = np;

	ams_info.exit = ams_pmu_exit;
@@ -161,10 +159,9 @@ int __init ams_pmu_init(struct device_node *np) 


	/* Get PMU command, should be 0x4e, but we can never know */

	prop = of_get_property(ams_info.of_node, "reg", NULL);

	if (!prop) {

		result = -ENODEV;

		goto exit;

	}

	if (!prop)

		return -ENODEV;



	ams_pmu_cmd = ((*prop) >> 8) & 0xff;



	/* Disable interrupts */
@@ -175,7 +172,7 @@ int __init ams_pmu_init(struct device_node *np) 


	result = ams_sensor_attach();

	if (result < 0)

		goto exit;

		return result;



	/* Set default values */

	ams_pmu_set_register(AMS_FF_LOW_LIMIT, 0x15);
@@ -198,10 +195,5 @@ int __init ams_pmu_init(struct device_node *np) 


	printk(KERN_INFO "ams: Found PMU based motion sensor\n");



	result = 0;



exit:

	mutex_unlock(&ams_info.lock);



	return result;

	return 0;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE