Skip to contentSkip to conversation

media: rc: reduce size of struct ir_raw_event

PATCH New Heiner Kallweit 1 participant 1 message Mar 17, 2016

Subsystems (2)
Media (V4L/DVB) RC-core / lirc framework
lore
Share & tools
lore

Heiner Kallweit

author
#0 lore raw

PATCH v2 1/1 media: rc: reduce size of struct ir_raw_event

struct ir_raw_event currently has a size of 12 bytes on most (all?) architectures. This can be reduced to 8 bytes whilst maintaining full backwards compatibility.
This saves 2KB in size of struct ir_raw_event_ctrl (as element kfifo is reduced by 512 * 4 bytes) and it allows to copy the full struct ir_raw_event with a single 64 bit operation.

Successfully tested with the Nuvoton driver and successfully compile-tested with the ene_ir driver (as it uses the carrier / duty_cycle elements).

Signed-off-by Heiner Kallweit <[email protected]>

---
v2:
- don't change type of bit field members

---
 include/media/rc-core.h | 18 ++++--------------
 1 file changed, 4 insertions(+), 14 deletions(-)
include/media/rc-core.h +4 -14
index 0f77b3d..f6f55b7 100644
@@ -215,12 +215,9 @@ enum raw_event_type {
 struct ir_raw_event {
 	union {
 		u32             duration;
-
-		struct {
-			u32     carrier;
-			u8      duty_cycle;
-		};
+		u32             carrier;
 	};
+	u8                      duty_cycle;
 
 	unsigned                pulse:1;
 	unsigned                reset:1;

@@ -228,13 +225,7 @@ struct ir_raw_event {
 	unsigned                carrier_report:1;
 };
 
-#define DEFINE_IR_RAW_EVENT(event) \
-	struct ir_raw_event event = { \
-		{ .duration = 0 } , \
-		.pulse = 0, \
-		.reset = 0, \
-		.timeout = 0, \
-		.carrier_report = 0 }
+#define DEFINE_IR_RAW_EVENT(event) struct ir_raw_event event = {}
 
 static inline void init_ir_raw_event(struct ir_raw_event *ev)
 {

@@ -256,8 +247,7 @@ void ir_raw_event_set_idle(struct rc_dev *dev, bool idle);
 
 static inline void ir_raw_event_reset(struct rc_dev *dev)
 {
-	DEFINE_IR_RAW_EVENT(ev);
-	ev.reset = true;
+	struct ir_raw_event ev = { .reset = true };
 
 	ir_raw_event_store(dev, &ev);
 	ir_raw_event_handle(dev);
Signature · 1 line
2.7.3