drivers/input/sparse-keymap.c
Source file repositories/reference/linux-study-clean/drivers/input/sparse-keymap.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/input/sparse-keymap.c- Extension
.c- Size
- 7646 bytes
- Lines
- 295
- Domain
- Driver Families
- Bucket
- drivers/input
- Inferred role
- Driver Families: exported/initcall integration point
- Status
- integration implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/export.hlinux/input.hlinux/input/sparse-keymap.hlinux/module.hlinux/slab.h
Detected Declarations
function sparse_keymap_get_key_indexfunction sparse_keymap_getkeycodefunction sparse_keymap_setkeycodefunction sparse_keymap_setupfunction sparse_keymap_report_entryfunction sparse_keymap_report_eventexport sparse_keymap_entry_from_scancodeexport sparse_keymap_entry_from_keycodeexport sparse_keymap_setupexport sparse_keymap_report_entryexport sparse_keymap_report_event
Annotated Snippet
if (key->type == KE_KEY) {
if (key == k)
break;
idx++;
}
}
return idx;
}
static struct key_entry *sparse_keymap_entry_by_index(struct input_dev *dev,
unsigned int index)
{
struct key_entry *key;
unsigned int key_cnt = 0;
for (key = dev->keycode; key->type != KE_END; key++)
if (key->type == KE_KEY)
if (key_cnt++ == index)
return key;
return NULL;
}
/**
* sparse_keymap_entry_from_scancode - perform sparse keymap lookup
* @dev: Input device using sparse keymap
* @code: Scan code
*
* This function is used to perform &struct key_entry lookup in an
* input device using sparse keymap.
*/
struct key_entry *sparse_keymap_entry_from_scancode(struct input_dev *dev,
unsigned int code)
{
struct key_entry *key;
for (key = dev->keycode; key->type != KE_END; key++)
if (code == key->code)
return key;
return NULL;
}
EXPORT_SYMBOL(sparse_keymap_entry_from_scancode);
/**
* sparse_keymap_entry_from_keycode - perform sparse keymap lookup
* @dev: Input device using sparse keymap
* @keycode: Key code
*
* This function is used to perform &struct key_entry lookup in an
* input device using sparse keymap.
*/
struct key_entry *sparse_keymap_entry_from_keycode(struct input_dev *dev,
unsigned int keycode)
{
struct key_entry *key;
for (key = dev->keycode; key->type != KE_END; key++)
if (key->type == KE_KEY && keycode == key->keycode)
return key;
return NULL;
}
EXPORT_SYMBOL(sparse_keymap_entry_from_keycode);
static struct key_entry *sparse_keymap_locate(struct input_dev *dev,
const struct input_keymap_entry *ke)
{
struct key_entry *key;
unsigned int scancode;
if (ke->flags & INPUT_KEYMAP_BY_INDEX)
key = sparse_keymap_entry_by_index(dev, ke->index);
else if (input_scancode_to_scalar(ke, &scancode) == 0)
key = sparse_keymap_entry_from_scancode(dev, scancode);
else
key = NULL;
return key;
}
static int sparse_keymap_getkeycode(struct input_dev *dev,
struct input_keymap_entry *ke)
{
const struct key_entry *key;
if (dev->keycode) {
key = sparse_keymap_locate(dev, ke);
if (key && key->type == KE_KEY) {
Annotation
- Immediate include surface: `linux/export.h`, `linux/input.h`, `linux/input/sparse-keymap.h`, `linux/module.h`, `linux/slab.h`.
- Detected declarations: `function sparse_keymap_get_key_index`, `function sparse_keymap_getkeycode`, `function sparse_keymap_setkeycode`, `function sparse_keymap_setup`, `function sparse_keymap_report_entry`, `function sparse_keymap_report_event`, `export sparse_keymap_entry_from_scancode`, `export sparse_keymap_entry_from_keycode`, `export sparse_keymap_setup`, `export sparse_keymap_report_entry`.
- Atlas domain: Driver Families / drivers/input.
- Implementation status: integration implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.