]> www.infradead.org Git - users/hch/misc.git/commitdiff
power: supply: 88pm860x: make fsm_state array static const, simplify usage
authorColin Ian King <colin.i.king@gmail.com>
Thu, 7 Aug 2025 12:13:49 +0000 (13:13 +0100)
committerSebastian Reichel <sebastian.reichel@collabora.com>
Sat, 6 Sep 2025 21:24:23 +0000 (23:24 +0200)
Don't populate the read-only array fsm_state on the stack at run time,
instead make it static const, this reduces the object code size as
the data is placed on the data segment and this removes the need to
have code to set the array up on each call.

Note that making the size of the strings to a more optimal 11 bytes long
does not seem to reduce the overall size. Making the array an array of
pointers to the strings increases the code size due to the dereferencing
overhead.

Simplify the array access with &fsm_state[info->state][0] with the simpler
expression fsm_state[info->state] to clean up the code.

Original:
   text    data     bss     dec     hex filename
  22884    8272      64   31220    79f4 drivers/power/supply/88pm860x_charger.o

Patched:
   text    data     bss     dec     hex filename
  22695    8368      64   31127    7997 drivers/power/supply/88pm860x_charger.o

Difference:
   text    data     bss     dec
  -189     +96        0     -93

Reduction of 93 bytes total.

gcc version 14.2.0 (x86-64)

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
drivers/power/supply/88pm860x_charger.c

index 2b9fcb7e71d79e0ce5f062d1c53db7948e4d7067..8d99c6ff72edf6e9c4a8e3c9325507f232d44090 100644 (file)
@@ -284,8 +284,8 @@ static int set_charging_fsm(struct pm860x_charger_info *info)
 {
        struct power_supply *psy;
        union power_supply_propval data;
-       unsigned char fsm_state[][16] = { "init", "discharge", "precharge",
-               "fastcharge",
+       static const unsigned char fsm_state[][16] = {
+               "init", "discharge", "precharge", "fastcharge",
        };
        int ret;
        int vbatt;
@@ -313,7 +313,7 @@ static int set_charging_fsm(struct pm860x_charger_info *info)
 
        dev_dbg(info->dev, "Entering FSM:%s, Charger:%s, Battery:%s, "
                "Allowed:%d\n",
-               &fsm_state[info->state][0],
+               fsm_state[info->state],
                (info->online) ? "online" : "N/A",
                (info->present) ? "present" : "N/A", info->allowed);
        dev_dbg(info->dev, "set_charging_fsm:vbatt:%d(mV)\n", vbatt);
@@ -385,7 +385,7 @@ static int set_charging_fsm(struct pm860x_charger_info *info)
        }
        dev_dbg(info->dev,
                "Out FSM:%s, Charger:%s, Battery:%s, Allowed:%d\n",
-               &fsm_state[info->state][0],
+               fsm_state[info->state],
                (info->online) ? "online" : "N/A",
                (info->present) ? "present" : "N/A", info->allowed);
        mutex_unlock(&info->lock);