From d33baed3fea26756ef3b077347b8da0de3f492f1 Mon Sep 17 00:00:00 2001 From: Shih-Yuan Lee Date: Sat, 11 Jul 2026 17:33:21 +0800 Subject: [PATCH] hwmon: (applesmc) Cache fan positions during register initialization To support the read_string callback for fan labels in the modern HWMON API, load and cache the fan position names in smcreg.fan_positions during register initialization. Pre-pad fallback labels with four spaces to match the "+ 4" pointer arithmetic offset used by all fan labels in the read_string callback. Signed-off-by: Shih-Yuan Lee Link: https://lore.kernel.org/r/20260711093323.14529-2-fourdollars@debian.org Signed-off-by: Guenter Roeck --- drivers/hwmon/applesmc.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c index 90a14a7f2c4c..9b2d9ecb20c0 100644 --- a/drivers/hwmon/applesmc.c +++ b/drivers/hwmon/applesmc.c @@ -133,6 +133,7 @@ static struct applesmc_registers { bool init_complete; /* true when fully initialized */ struct applesmc_entry *cache; /* cached key entries */ const char **index; /* temperature key index */ + char fan_positions[10][17]; /* cached fan position labels */ } smcreg = { .mutex = __MUTEX_INITIALIZER(smcreg.mutex), }; @@ -566,7 +567,7 @@ static int applesmc_init_smcreg_try(void) { struct applesmc_registers *s = &smcreg; bool left_light_sensor = false, right_light_sensor = false; - unsigned int count; + unsigned int count, i; u8 tmp[1]; int ret; @@ -597,6 +598,16 @@ static int applesmc_init_smcreg_try(void) if (s->fan_count > 10) s->fan_count = 10; + for (i = 0; i < s->fan_count; i++) { + char newkey[5]; + + scnprintf(newkey, sizeof(newkey), FAN_ID_FMT, i); + ret = applesmc_read_key(newkey, s->fan_positions[i], 16); + s->fan_positions[i][16] = 0; + if (ret) + scnprintf(s->fan_positions[i], 17, " Fan %d", i); + } + ret = applesmc_get_lower_bound(&s->temp_begin, "T"); if (ret) return ret;