V4L/DVB: drivers/media/IR - improve keytable code (b3074c0a) · Commits · e / devices / android_kernel_fairphone_FP5

drivers/media/IR/ir-keytable.c

+188 −330

Original line number	Diff line number	Diff line
		@@ -17,344 +17,214 @@
		#include <linux/slab.h>
		#include <media/ir-common.h>

		#define IR_TAB_MIN_SIZE 32
		#define IR_TAB_MAX_SIZE 1024
		/* Sizes are in bytes, 256 bytes allows for 32 entries on x64 */
		#define IR_TAB_MIN_SIZE 256
		#define IR_TAB_MAX_SIZE 8192

		/**
		* ir_seek_table() - returns the element order on the table
		* @rc_tab: the ir_scancode_table with the keymap to be used
		* @scancode: the scancode that we're seeking
		* ir_resize_table() - resizes a scancode table if necessary
		* @rc_tab: the ir_scancode_table to resize
		* @return: zero on success or a negative error code
		*
		* This routine is used by the input routines when a key is pressed at the
		* IR. The scancode is received and needs to be converted into a keycode.
		* If the key is not found, it returns KEY_UNKNOWN. Otherwise, returns the
		* corresponding keycode from the table.
		* This routine will shrink the ir_scancode_table if it has lots of
		* unused entries and grow it if it is full.
		*/
		static int ir_seek_table(struct ir_scancode_table *rc_tab, u32 scancode)
		static int ir_resize_table(struct ir_scancode_table *rc_tab)
		{
		int rc;
		unsigned long flags;
		struct ir_scancode *keymap = rc_tab->scan;
		unsigned int oldalloc = rc_tab->alloc;
		unsigned int newalloc = oldalloc;
		struct ir_scancode *oldscan = rc_tab->scan;
		struct ir_scancode *newscan;

		if (rc_tab->size == rc_tab->len) {
		/* All entries in use -> grow keytable */
		if (rc_tab->alloc >= IR_TAB_MAX_SIZE)
		return -ENOMEM;

		spin_lock_irqsave(&rc_tab->lock, flags);
		newalloc *= 2;
		IR_dprintk(1, "Growing table to %u bytes\n", newalloc);
		}

		/* FIXME: replace it by a binary search */
		if ((rc_tab->len * 3 < rc_tab->size) && (oldalloc > IR_TAB_MIN_SIZE)) {
		/* Less than 1/3 of entries in use -> shrink keytable */
		newalloc /= 2;
		IR_dprintk(1, "Shrinking table to %u bytes\n", newalloc);
		}

		for (rc = 0; rc < rc_tab->size; rc++)
		if (keymap[rc].scancode == scancode)
		goto exit;
		if (newalloc == oldalloc)
		return 0;

		/* Not found */
		rc = -EINVAL;
		newscan = kmalloc(newalloc, GFP_ATOMIC);
		if (!newscan) {
		IR_dprintk(1, "Failed to kmalloc %u bytes\n", newalloc);
		return -ENOMEM;
		}

		exit:
		spin_unlock_irqrestore(&rc_tab->lock, flags);
		return rc;
		memcpy(newscan, rc_tab->scan, rc_tab->len * sizeof(struct ir_scancode));
		rc_tab->scan = newscan;
		rc_tab->alloc = newalloc;
		rc_tab->size = rc_tab->alloc / sizeof(struct ir_scancode);
		kfree(oldscan);
		return 0;
		}

		/**
		* ir_roundup_tablesize() - gets an optimum value for the table size
		* @n_elems: minimum number of entries to store keycodes
		*
		* This routine is used to choose the keycode table size.
		* ir_do_setkeycode() - internal function to set a keycode in the
		* scancode->keycode table
		* @dev: the struct input_dev device descriptor
		* @rc_tab: the struct ir_scancode_table to set the keycode in
		* @scancode: the scancode for the ir command
		* @keycode: the keycode for the ir command
		* @return: -EINVAL if the keycode could not be inserted, otherwise zero.
		*
		* In order to have some empty space for new keycodes,
		* and knowing in advance that kmalloc allocates only power of two
		* segments, it optimizes the allocated space to have some spare space
		* for those new keycodes by using the maximum number of entries that
		* will be effectively be allocated by kmalloc.
		* In order to reduce the quantity of table resizes, it has a minimum
		* table size of IR_TAB_MIN_SIZE.
		* This routine is used internally to manipulate the scancode->keycode table.
		* The caller has to hold @rc_tab->lock.
		*/
		static int ir_roundup_tablesize(int n_elems)
		static int ir_do_setkeycode(struct input_dev *dev,
		struct ir_scancode_table *rc_tab,
		unsigned scancode, unsigned keycode)
		{
		size_t size;

		if (n_elems < IR_TAB_MIN_SIZE)
		n_elems = IR_TAB_MIN_SIZE;
		unsigned int i;
		int old_keycode = KEY_RESERVED;

		/* First check if we already have a mapping for this ir command */
		for (i = 0; i < rc_tab->len; i++) {
		/* Keytable is sorted from lowest to highest scancode */
		if (rc_tab->scan[i].scancode > scancode)
		break;
		else if (rc_tab->scan[i].scancode < scancode)
		continue;

		/*
		* As kmalloc only allocates sizes of power of two, get as
		* much entries as possible for the allocated memory segment
		*/
		size = roundup_pow_of_two(n_elems * sizeof(struct ir_scancode));
		n_elems = size / sizeof(struct ir_scancode);
		old_keycode = rc_tab->scan[i].keycode;
		rc_tab->scan[i].keycode = keycode;

		return n_elems;
		/* Did the user wish to remove the mapping? */
		if (keycode == KEY_RESERVED \|\| keycode == KEY_UNKNOWN) {
		rc_tab->len--;
		memmove(&rc_tab->scan[i], &rc_tab->scan[i + 1],
		(rc_tab->len - i) * sizeof(struct ir_scancode));
		}

		/**
		* ir_copy_table() - copies a keytable, discarding the unused entries
		* @destin: destin table
		* @origin: origin table
		*
		* Copies all entries where the keycode is not KEY_UNKNOWN/KEY_RESERVED
		* Also copies table size and table protocol.
		* NOTE: It shouldn't copy the lock field
		*/

		static int ir_copy_table(struct ir_scancode_table *destin,
		const struct ir_scancode_table *origin)
		{
		int i, j = 0;
		/* Possibly shrink the keytable, failure is not a problem */
		ir_resize_table(rc_tab);
		break;
		}

		for (i = 0; i < origin->size; i++) {
		if (origin->scan[i].keycode == KEY_UNKNOWN \|\|
		origin->scan[i].keycode == KEY_RESERVED)
		continue;
		if (old_keycode == KEY_RESERVED) {
		/* No previous mapping found, we might need to grow the table */
		if (ir_resize_table(rc_tab))
		return -ENOMEM;

		memcpy(&destin->scan[j], &origin->scan[i], sizeof(struct ir_scancode));
		j++;
		/* i is the proper index to insert our new keycode */
		memmove(&rc_tab->scan[i + 1], &rc_tab->scan[i],
		(rc_tab->len - i) * sizeof(struct ir_scancode));
		rc_tab->scan[i].scancode = scancode;
		rc_tab->scan[i].keycode = keycode;
		rc_tab->len++;
		set_bit(keycode, dev->keybit);
		} else {
		/* A previous mapping was updated... */
		clear_bit(old_keycode, dev->keybit);
		/* ...but another scancode might use the same keycode */
		for (i = 0; i < rc_tab->len; i++) {
		if (rc_tab->scan[i].keycode == old_keycode) {
		set_bit(old_keycode, dev->keybit);
		break;
		}
		}
		}
		destin->size = j;
		destin->ir_type = origin->ir_type;

		IR_dprintk(1, "Copied %d scancodes to the new keycode table\n", destin->size);

		return 0;
		}

		/**
		* ir_getkeycode() - get a keycode at the evdev scancode ->keycode table
		* ir_setkeycode() - set a keycode in the scancode->keycode table
		* @dev: the struct input_dev device descriptor
		* @scancode: the desired scancode
		* @keycode: the keycode to be retorned.
		* @keycode: result
		* @return: -EINVAL if the keycode could not be inserted, otherwise zero.
		*
		* This routine is used to handle evdev EVIOCGKEY ioctl.
		* If the key is not found, returns -EINVAL, otherwise, returns 0.
		* This routine is used to handle evdev EVIOCSKEY ioctl.
		*/
		static int ir_getkeycode(struct input_dev *dev,
		unsigned int scancode, unsigned int *keycode)
		static int ir_setkeycode(struct input_dev *dev,
		unsigned int scancode, unsigned int keycode)
		{
		int elem;
		int rc;
		unsigned long flags;
		struct ir_input_dev *ir_dev = input_get_drvdata(dev);
		struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;

		elem = ir_seek_table(rc_tab, scancode);
		if (elem >= 0) {
		*keycode = rc_tab->scan[elem].keycode;
		return 0;
		}

		/*
		* Scancode not found and table can't be expanded
		*/
		if (elem < 0 && rc_tab->size == IR_TAB_MAX_SIZE)
		return -EINVAL;

		/*
		* If is there extra space, returns KEY_RESERVED,
		* otherwise, input core won't let ir_setkeycode to work
		*/
		*keycode = KEY_RESERVED;
		return 0;
		}

		/**
		* ir_is_resize_needed() - Check if the table needs rezise
		* @table: keycode table that may need to resize
		* @n_elems: minimum number of entries to store keycodes
		*
		* Considering that kmalloc uses power of two storage areas, this
		* routine detects if the real alloced size will change. If not, it
		* just returns without doing nothing. Otherwise, it will extend or
		* reduce the table size to meet the new needs.
		*
		* It returns 0 if no resize is needed, 1 otherwise.
		*/
		static int ir_is_resize_needed(struct ir_scancode_table *table, int n_elems)
		{
		int cur_size = ir_roundup_tablesize(table->size);
		int new_size = ir_roundup_tablesize(n_elems);

		if (cur_size == new_size)
		return 0;

		/* Resize is needed */
		return 1;
		}

		/**
		* ir_delete_key() - remove a keycode from the table
		* @rc_tab: keycode table
		* @elem: element to be removed
		*
		*/
		static void ir_delete_key(struct ir_scancode_table *rc_tab, int elem)
		{
		unsigned long flags = 0;
		int newsize = rc_tab->size - 1;
		int resize = ir_is_resize_needed(rc_tab, newsize);
		struct ir_scancode *oldkeymap = rc_tab->scan;
		struct ir_scancode *newkeymap = NULL;

		if (resize)
		newkeymap = kzalloc(ir_roundup_tablesize(newsize) *
		sizeof(*newkeymap), GFP_ATOMIC);

		/* There's no memory for resize. Keep the old table */
		if (!resize \|\| !newkeymap) {
		newkeymap = oldkeymap;

		/* We'll modify the live table. Lock it */
		spin_lock_irqsave(&rc_tab->lock, flags);
		}

		/*
		* Copy the elements before the one that will be deleted
		* if (!resize), both oldkeymap and newkeymap points
		* to the same place, so, there's no need to copy
		*/
		if (resize && elem > 0)
		memcpy(newkeymap, oldkeymap,
		elem * sizeof(*newkeymap));

		/*
		* Copy the other elements overwriting the element to be removed
		* This operation applies to both resize and non-resize case
		*/
		if (elem < newsize)
		memcpy(&newkeymap[elem], &oldkeymap[elem + 1],
		(newsize - elem) * sizeof(*newkeymap));

		if (resize) {
		/*
		* As the copy happened to a temporary table, only here
		* it needs to lock while replacing the table pointers
		* to use the new table
		*/
		spin_lock_irqsave(&rc_tab->lock, flags);
		rc_tab->size = newsize;
		rc_tab->scan = newkeymap;
		rc = ir_do_setkeycode(dev, rc_tab, scancode, keycode);
		spin_unlock_irqrestore(&rc_tab->lock, flags);

		/* Frees the old keytable */
		kfree(oldkeymap);
		} else {
		rc_tab->size = newsize;
		spin_unlock_irqrestore(&rc_tab->lock, flags);
		}
		return rc;
		}

		/**
		* ir_insert_key() - insert a keycode at the table
		* @rc_tab: keycode table
		* @scancode: the desired scancode
		* @keycode: the keycode to be retorned.
		* ir_setkeytable() - sets several entries in the scancode->keycode table
		* @dev: the struct input_dev device descriptor
		* @to: the struct ir_scancode_table to copy entries to
		* @from: the struct ir_scancode_table to copy entries from
		* @return: -EINVAL if all keycodes could not be inserted, otherwise zero.
		*
		* This routine is used to handle table initialization.
		*/
		static int ir_insert_key(struct ir_scancode_table *rc_tab,
		int scancode, int keycode)
		static int ir_setkeytable(struct input_dev *dev,
		struct ir_scancode_table *to,
		const struct ir_scancode_table *from)
		{
		struct ir_input_dev *ir_dev = input_get_drvdata(dev);
		struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
		unsigned long flags;
		int elem = rc_tab->size;
		int newsize = rc_tab->size + 1;
		int resize = ir_is_resize_needed(rc_tab, newsize);
		struct ir_scancode *oldkeymap = rc_tab->scan;
		struct ir_scancode *newkeymap;

		if (resize) {
		newkeymap = kzalloc(ir_roundup_tablesize(newsize) *
		sizeof(*newkeymap), GFP_ATOMIC);
		if (!newkeymap)
		return -ENOMEM;

		memcpy(newkeymap, oldkeymap,
		rc_tab->size * sizeof(*newkeymap));
		} else
		newkeymap = oldkeymap;

		/* Stores the new code at the table */
		IR_dprintk(1, "#%d: New scan 0x%04x with key 0x%04x\n",
		rc_tab->size, scancode, keycode);
		unsigned int i;
		int rc = 0;

		spin_lock_irqsave(&rc_tab->lock, flags);
		rc_tab->size = newsize;
		if (resize) {
		rc_tab->scan = newkeymap;
		kfree(oldkeymap);
		for (i = 0; i < from->size; i++) {
		rc = ir_do_setkeycode(dev, to, from->scan[i].scancode,
		from->scan[i].keycode);
		if (rc)
		break;
		}
		newkeymap[elem].scancode = scancode;
		newkeymap[elem].keycode = keycode;
		spin_unlock_irqrestore(&rc_tab->lock, flags);

		return 0;
		return rc;
		}

		/**
		* ir_setkeycode() - set a keycode at the evdev scancode ->keycode table
		* ir_getkeycode() - get a keycode from the scancode->keycode table
		* @dev: the struct input_dev device descriptor
		* @scancode: the desired scancode
		* @keycode: the keycode to be retorned.
		* @keycode: used to return the keycode, if found, or KEY_RESERVED
		* @return: always returns zero.
		*
		* This routine is used to handle evdev EVIOCSKEY ioctl.
		* There's one caveat here: how can we increase the size of the table?
		* If the key is not found, returns -EINVAL, otherwise, returns 0.
		* This routine is used to handle evdev EVIOCGKEY ioctl.
		*/
		static int ir_setkeycode(struct input_dev *dev,
		unsigned int scancode, unsigned int keycode)
		static int ir_getkeycode(struct input_dev *dev,
		unsigned int scancode, unsigned int *keycode)
		{
		int rc = 0;
		int start, end, mid;
		unsigned long flags;
		int key = KEY_RESERVED;
		struct ir_input_dev *ir_dev = input_get_drvdata(dev);
		struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
		struct ir_scancode *keymap = rc_tab->scan;
		unsigned long flags;

		/*
		* Handle keycode table deletions
		*
		* If userspace is adding a KEY_UNKNOWN or KEY_RESERVED,
		* deal as a trial to remove an existing scancode attribution
		* if table become too big, reduce it to save space
		*/
		if (keycode == KEY_UNKNOWN \|\| keycode == KEY_RESERVED) {
		rc = ir_seek_table(rc_tab, scancode);
		if (rc < 0)
		return 0;

		IR_dprintk(1, "#%d: Deleting scan 0x%04x\n", rc, scancode);
		clear_bit(keymap[rc].keycode, dev->keybit);
		ir_delete_key(rc_tab, rc);

		return 0;
		}

		/*
		* Handle keycode replacements
		*
		* If the scancode exists, just replace by the new value
		*/
		rc = ir_seek_table(rc_tab, scancode);
		if (rc >= 0) {
		IR_dprintk(1, "#%d: Replacing scan 0x%04x with key 0x%04x\n",
		rc, scancode, keycode);

		clear_bit(keymap[rc].keycode, dev->keybit);

		spin_lock_irqsave(&rc_tab->lock, flags);
		keymap[rc].keycode = keycode;
		spin_unlock_irqrestore(&rc_tab->lock, flags);

		set_bit(keycode, dev->keybit);

		return 0;
		start = 0;
		end = rc_tab->len - 1;
		while (start <= end) {
		mid = (start + end) / 2;
		if (rc_tab->scan[mid].scancode < scancode)
		start = mid + 1;
		else if (rc_tab->scan[mid].scancode > scancode)
		end = mid - 1;
		else {
		key = rc_tab->scan[mid].keycode;
		break;
		}
		}
		spin_unlock_irqrestore(&rc_tab->lock, flags);

		/*
		* Handle new scancode inserts
		*
		* reallocate table if needed and insert a new keycode
		*/

		/* Avoid growing the table indefinitely */
		if (rc_tab->size + 1 > IR_TAB_MAX_SIZE)
		return -EINVAL;

		rc = ir_insert_key(rc_tab, scancode, keycode);
		if (rc < 0)
		return rc;
		set_bit(keycode, dev->keybit);

		*keycode = key;
		return 0;
		}

		@@ -370,24 +240,12 @@ static int ir_setkeycode(struct input_dev *dev,
		*/
		u32 ir_g_keycode_from_table(struct input_dev *dev, u32 scancode)
		{
		struct ir_input_dev *ir_dev = input_get_drvdata(dev);
		struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
		struct ir_scancode *keymap = rc_tab->scan;
		int elem;
		int keycode;

		elem = ir_seek_table(rc_tab, scancode);
		if (elem >= 0) {
		ir_getkeycode(dev, scancode, &keycode);
		IR_dprintk(1, "%s: scancode 0x%04x keycode 0x%02x\n",
		dev->name, scancode, keymap[elem].keycode);

		return rc_tab->scan[elem].keycode;
		}

		printk(KERN_INFO "%s: unknown key for scancode 0x%04x\n",
		dev->name, scancode);

		/* Reports userspace that an unknown keycode were got */
		return KEY_RESERVED;
		dev->name, scancode, keycode);
		return keycode;
		}
		EXPORT_SYMBOL_GPL(ir_g_keycode_from_table);

		@@ -477,8 +335,7 @@ int __ir_input_register(struct input_dev *input_dev,
		const char *driver_name)
		{
		struct ir_input_dev *ir_dev;
		struct ir_scancode *keymap = rc_tab->scan;
		int i, rc;
		int rc;

		if (rc_tab->scan == NULL \|\| !rc_tab->size)
		return -EINVAL;
		@@ -487,55 +344,55 @@ int __ir_input_register(struct input_dev *input_dev,
		if (!ir_dev)
		return -ENOMEM;

		spin_lock_init(&ir_dev->rc_tab.lock);
		ir_dev->driver_name = kasprintf(GFP_KERNEL, "%s", driver_name);
		if (!ir_dev->driver_name) {
		rc = -ENOMEM;
		goto out_dev;
		}

		ir_dev->driver_name = kmalloc(strlen(driver_name) + 1, GFP_KERNEL);
		if (!ir_dev->driver_name)
		return -ENOMEM;
		strcpy(ir_dev->driver_name, driver_name);
		input_dev->getkeycode = ir_getkeycode;
		input_dev->setkeycode = ir_setkeycode;
		input_set_drvdata(input_dev, ir_dev);

		spin_lock_init(&ir_dev->rc_tab.lock);
		ir_dev->rc_tab.name = rc_tab->name;
		ir_dev->rc_tab.size = ir_roundup_tablesize(rc_tab->size);
		ir_dev->rc_tab.scan = kzalloc(ir_dev->rc_tab.size *
		sizeof(struct ir_scancode), GFP_KERNEL);
		ir_dev->rc_tab.ir_type = rc_tab->ir_type;
		ir_dev->rc_tab.alloc = roundup_pow_of_two(rc_tab->size *
		sizeof(struct ir_scancode));
		ir_dev->rc_tab.scan = kmalloc(ir_dev->rc_tab.alloc, GFP_KERNEL);
		ir_dev->rc_tab.size = ir_dev->rc_tab.alloc / sizeof(struct ir_scancode);

		if (!ir_dev->rc_tab.scan) {
		kfree(ir_dev);
		return -ENOMEM;
		rc = -ENOMEM;
		goto out_name;
		}

		IR_dprintk(1, "Allocated space for %d keycode entries (%zd bytes)\n",
		ir_dev->rc_tab.size,
		ir_dev->rc_tab.size * sizeof(ir_dev->rc_tab.scan));
		IR_dprintk(1, "Allocated space for %u keycode entries (%u bytes)\n",
		ir_dev->rc_tab.size, ir_dev->rc_tab.alloc);

		set_bit(EV_KEY, input_dev->evbit);
		if (ir_setkeytable(input_dev, &ir_dev->rc_tab, rc_tab)) {
		rc = -ENOMEM;
		goto out_table;
		}

		ir_copy_table(&ir_dev->rc_tab, rc_tab);
		ir_dev->props = props;
		if (props && props->open)
		input_dev->open = ir_open;
		if (props && props->close)
		input_dev->close = ir_close;

		/* set the bits for the keys */
		IR_dprintk(1, "key map size: %d\n", rc_tab->size);
		for (i = 0; i < rc_tab->size; i++) {
		IR_dprintk(1, "#%d: setting bit for keycode 0x%04x\n",
		i, keymap[i].keycode);
		set_bit(keymap[i].keycode, input_dev->keybit);
		}
		clear_bit(0, input_dev->keybit);

		set_bit(EV_KEY, input_dev->evbit);

		input_dev->getkeycode = ir_getkeycode;
		input_dev->setkeycode = ir_setkeycode;
		input_set_drvdata(input_dev, ir_dev);

		rc = ir_register_class(input_dev);
		if (rc < 0)
		goto err;
		goto out_table;

		return 0;

		err:
		kfree(rc_tab->scan);
		out_table:
		kfree(ir_dev->rc_tab.scan);
		out_name:
		kfree(ir_dev->driver_name);
		out_dev:
		kfree(ir_dev);
		return rc;
		}
		@@ -564,6 +421,7 @@ void ir_input_unregister(struct input_dev *dev)

		ir_unregister_class(dev);

		kfree(ir_dev->driver_name);
		kfree(ir_dev);
		}
		EXPORT_SYMBOL_GPL(ir_input_unregister);

include/media/ir-core.h

+3 −1

Original line number	Diff line number	Diff line
		@@ -47,7 +47,9 @@ struct ir_scancode {

		struct ir_scancode_table {
		struct ir_scancode *scan;
		int size;
		unsigned int size; /* Max number of entries */
		unsigned int len; /* Used number of entries */
		unsigned int alloc; /* Size of scan in bytes /
		u64 ir_type;
		char *name;
		spinlock_t lock;