Re: [PATCH] power: supply: macsmc: Support macOS 27 SMC firmware

From: Sven Peter

Date: Thu Jun 11 2026 - 13:09:34 EST


On 11.06.26 18:49, Sasha Finkelstein wrote:
The SMC firmware included in macOS 27 changed the size of BCF0 key from
4 to 1 bytes. This key is used for indicating that battery state is
critically low.

Signed-off-by: Sasha Finkelstein <k@xxxxxxxxxxxxxx>
---
drivers/power/supply/macsmc-power.c | 34 +++++++++++++++++++++++++++++++---
1 file changed, 31 insertions(+), 3 deletions(-)

diff --git a/drivers/power/supply/macsmc-power.c b/drivers/power/supply/macsmc-power.c
index 33ca07460f3a..650dc8740f71 100644
--- a/drivers/power/supply/macsmc-power.c
+++ b/drivers/power/supply/macsmc-power.c
@@ -86,6 +86,7 @@ struct macsmc_power {
bool has_ch0i; /* Force discharge (Older firmware) */
bool has_ch0c; /* Inhibit charge (Older firmware) */
bool has_chte; /* Inhibit charge (Modern firmware) */
+ bool bcf0_1byte; /* Battery critical */

The comment is a bit misleading, maybe "Battery critical key is 1 instead of 4 bytes" or "Battery critical key is 1 byte (Modern firmware)" instead?

With that changed:

Reviewed-by: Sven Peter <sven@xxxxxxxxxx>



Best,


Sven