Define data structure for all associated LEDs Add list of associated LEDs and list search helper Add trigger mutex - must be held when accessing trigger/LED or device/LED associations Signed-off-by: Ian Pilcher <arequipeno@gmail.com> --- block/blk-ledtrig.c | 48 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 block/blk-ledtrig.c diff --git a/block/blk-ledtrig.c b/block/blk-ledtrig.c new file mode 100644 index 000000000000..c5ad57ed9c3b --- /dev/null +++ b/block/blk-ledtrig.c @@ -0,0 +1,48 @@ +// SPDX-License-Identifier: GPL-2.0-only + +/* + * Block device LED triggers + * + * Copyright 2021 Ian Pilcher <arequipeno@gmail.com> + */ + +#include <linux/leds.h> +#include <linux/mutex.h> + +/* + * + * Trigger mutex and LED list + * + */ + +// Must hold when doing anything with LED/trigger/block device +// associations +static DEFINE_MUTEX(blk_ledtrig_mutex); + +static LIST_HEAD(blk_ledtrig_leds); + +// Every LED associated with the blkdev trigger gets one of these +struct blk_ledtrig_led { + struct kobject *dir; // block_devices subdirectory + struct led_classdev *led; + unsigned int blink_on; + unsigned int blink_off; + struct list_head leds_list_node; + struct list_head dev_list; +}; + +// Caller must hold blk_ledtrig_mutex +static struct blk_ledtrig_led *blk_ledtrig_find(const char *const led_name, + const size_t name_len) +{ + struct blk_ledtrig_led *bd_led; + + list_for_each_entry(bd_led, &blk_ledtrig_leds, leds_list_node) { + if (strlen(bd_led->led->name) != name_len) + continue; + if (memcmp(bd_led->led->name, led_name, name_len) == 0) + return bd_led; + } + + return NULL; +} -- 2.31.1