Commit 18726a34 authored by David Härdeman's avatar David Härdeman Committed by Mauro Carvalho Chehab
Browse files

[media] rc-core: cleanup rc_register_device pt2 



Now that rc_register_device() is reorganised, the dev->initialized
hack can be removed. Any driver which calls rc_register_device()
must be prepared for the device to go live immediately.

The dev->initialized commits that are relevant are commit c73bbaa4
("[media] rc-core: don't lock device at rc_register_device()") and
commit 08aeb7c9 ("[media] rc: add locking to fix register/show race").

The original problem was that show_protocols() would access
dev->rc_map.* and various other bits which are now properly
initialized before device_add() is called.

At the same time, remove the bogus "device is being removed" check.

Signed-off-by: default avatarDavid Härdeman <david@hardeman.nu>
Signed-off-by: default avatarSean Young <sean@mess.org>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
parent f56928ab

drivers/media/rc/rc-main.c

+10 −57
Original line number Diff line number Diff line
@@ -15,7 +15,6 @@ 
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt



#include <media/rc-core.h>

#include <linux/atomic.h>

#include <linux/spinlock.h>

#include <linux/delay.h>

#include <linux/input.h>
@@ -934,8 +933,8 @@ static bool lirc_is_present(void) 
 * It returns the protocol names of supported protocols.

 * Enabled protocols are printed in brackets.

 *

 * dev->lock is taken to guard against races between device

 * registration, store_protocols and show_protocols.

 * dev->lock is taken to guard against races between

 * store_protocols and show_protocols.

 */

static ssize_t show_protocols(struct device *device,

			      struct device_attribute *mattr, char *buf)
@@ -945,13 +944,6 @@ static ssize_t show_protocols(struct device *device, 
	char *tmp = buf;

	int i;



	/* Device is being removed */

	if (!dev)

		return -EINVAL;



	if (!atomic_read(&dev->initialized))

		return -ERESTARTSYS;



	mutex_lock(&dev->lock);



	enabled = dev->enabled_protocols;
@@ -1106,8 +1098,8 @@ static void ir_raw_load_modules(u64 *protocols) 
 * See parse_protocol_change() for the valid commands.

 * Returns @len on success or a negative error code.

 *

 * dev->lock is taken to guard against races between device

 * registration, store_protocols and show_protocols.

 * dev->lock is taken to guard against races between

 * store_protocols and show_protocols.

 */

static ssize_t store_protocols(struct device *device,

			       struct device_attribute *mattr,
@@ -1119,13 +1111,6 @@ static ssize_t store_protocols(struct device *device, 
	u64 old_protocols, new_protocols;

	ssize_t rc;



	/* Device is being removed */

	if (!dev)

		return -EINVAL;



	if (!atomic_read(&dev->initialized))

		return -ERESTARTSYS;



	IR_dprintk(1, "Normal protocol change requested\n");

	current_protocols = &dev->enabled_protocols;

	filter = &dev->scancode_filter;
@@ -1200,7 +1185,7 @@ out: 
 * Bits of the filter value corresponding to set bits in the filter mask are

 * compared against input scancodes and non-matching scancodes are discarded.

 *

 * dev->lock is taken to guard against races between device registration,

 * dev->lock is taken to guard against races between

 * store_filter and show_filter.

 */

static ssize_t show_filter(struct device *device,
@@ -1212,13 +1197,6 @@ static ssize_t show_filter(struct device *device, 
	struct rc_scancode_filter *filter;

	u32 val;



	/* Device is being removed */

	if (!dev)

		return -EINVAL;



	if (!atomic_read(&dev->initialized))

		return -ERESTARTSYS;



	mutex_lock(&dev->lock);



	if (fattr->type == RC_FILTER_NORMAL)
@@ -1251,7 +1229,7 @@ static ssize_t show_filter(struct device *device, 
 * Bits of the filter value corresponding to set bits in the filter mask are

 * compared against input scancodes and non-matching scancodes are discarded.

 *

 * dev->lock is taken to guard against races between device registration,

 * dev->lock is taken to guard against races between

 * store_filter and show_filter.

 */

static ssize_t store_filter(struct device *device,
@@ -1265,13 +1243,6 @@ static ssize_t store_filter(struct device *device, 
	unsigned long val;

	int (*set_filter)(struct rc_dev *dev, struct rc_scancode_filter *filter);



	/* Device is being removed */

	if (!dev)

		return -EINVAL;



	if (!atomic_read(&dev->initialized))

		return -ERESTARTSYS;



	ret = kstrtoul(buf, 0, &val);

	if (ret < 0)

		return ret;
@@ -1372,8 +1343,8 @@ static const char * const proto_variant_names[] = { 
 * It returns the protocol names of supported protocols.

 * The enabled protocols are printed in brackets.

 *

 * dev->lock is taken to guard against races between device

 * registration, store_protocols and show_protocols.

 * dev->lock is taken to guard against races between

 * store_wakeup_protocols and show_wakeup_protocols.

 */

static ssize_t show_wakeup_protocols(struct device *device,

				     struct device_attribute *mattr,
@@ -1385,13 +1356,6 @@ static ssize_t show_wakeup_protocols(struct device *device, 
	char *tmp = buf;

	int i;



	/* Device is being removed */

	if (!dev)

		return -EINVAL;



	if (!atomic_read(&dev->initialized))

		return -ERESTARTSYS;



	mutex_lock(&dev->lock);



	allowed = dev->allowed_wakeup_protocols;
@@ -1431,8 +1395,8 @@ static ssize_t show_wakeup_protocols(struct device *device, 
 * It is trigged by writing to /sys/class/rc/rc?/wakeup_protocols.

 * Returns @len on success or a negative error code.

 *

 * dev->lock is taken to guard against races between device

 * registration, store_protocols and show_protocols.

 * dev->lock is taken to guard against races between

 * store_wakeup_protocols and show_wakeup_protocols.

 */

static ssize_t store_wakeup_protocols(struct device *device,

				      struct device_attribute *mattr,
@@ -1444,13 +1408,6 @@ static ssize_t store_wakeup_protocols(struct device *device, 
	u64 allowed;

	int i;



	/* Device is being removed */

	if (!dev)

		return -EINVAL;



	if (!atomic_read(&dev->initialized))

		return -ERESTARTSYS;



	mutex_lock(&dev->lock);



	allowed = dev->allowed_wakeup_protocols;
@@ -1773,7 +1730,6 @@ int rc_register_device(struct rc_dev *dev) 
	dev->minor = minor;

	dev_set_name(&dev->dev, "rc%u", dev->minor);

	dev_set_drvdata(&dev->dev, dev);

	atomic_set(&dev->initialized, 0);



	dev->dev.groups = dev->sysfs_groups;

	if (dev->driver_type != RC_DRIVER_IR_RAW_TX)
@@ -1819,9 +1775,6 @@ int rc_register_device(struct rc_dev *dev) 
			goto out_rx;

	}



	/* Allow the RC sysfs nodes to be accessible */

	atomic_set(&dev->initialized, 1);



	IR_dprintk(1, "Registered rc%u (driver: %s)\n",

		   dev->minor,

		   dev->driver_name ? dev->driver_name : "unknown");

include/media/rc-core.h

+0 −2
Original line number Diff line number Diff line
@@ -70,7 +70,6 @@ enum rc_filter_type { 
/**

 * struct rc_dev - represents a remote control device

 * @dev: driver model's view of this device

 * @initialized: 1 if the device init has completed, 0 otherwise

 * @managed_alloc: devm_rc_allocate_device was used to create rc_dev

 * @sysfs_groups: sysfs attribute groups

 * @input_name: name of the input child device
@@ -137,7 +136,6 @@ enum rc_filter_type { 
 */

struct rc_dev {

	struct device			dev;

	atomic_t			initialized;

	bool				managed_alloc;

	const struct attribute_group	*sysfs_groups[5];

	const char			*input_name;

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