FAN53555BUC23X has the ID 0 and REV 0xc, starts at 600mV and
increments in 12.5mV steps.

Per the datasheet, the FAN53555BUC23X (23 option) is grouped with
the 00 and 13 options for soft-start timing (t_SS = 300us typ.),
so the existing enable_time = 400 is reused here as well.

This variant is found on the ASUS Tinker Edge R (RK3399Pro) as the
supply regulator for both vdd_gpu and vdd_cpu_b. Verified across
the full GPU OPP table with the userspace devfreq governor.

Signed-off-by: Arash Golgol <arash.golgol@gmail.com>
---
 drivers/regulator/fan53555.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/regulator/fan53555.c b/drivers/regulator/fan53555.c
index c282236959b1..59155cad99bc 100644
--- a/drivers/regulator/fan53555.c
+++ b/drivers/regulator/fan53555.c
@@ -113,6 +113,7 @@ enum {
 enum {
 	FAN53555_CHIP_REV_00 = 0x3,
 	FAN53555_CHIP_REV_13 = 0xf,
+	FAN53555_CHIP_REV_23 = 0xc,
 };
 
 enum {
@@ -305,6 +306,11 @@ static int fan53555_voltages_setup_fairchild(struct fan53555_device_info *di)
 			di->vsel_step = 10000;
 			di->enable_time = 400;
 			break;
+		case FAN53555_CHIP_REV_23:
+			di->vsel_min = 600000;
+			di->vsel_step = 12500;
+			di->enable_time = 400;
+			break;
 		default:
 			dev_err(di->dev,
 				"Chip ID %d with rev %d not supported!\n",
-- 
2.34.1

On Wed, 12 Aug 2026 16:20:54 +0330, Arash Golgol wrote:
> regulator: fan53555: Add support for FAN53555BUC23X type

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-7.3

Thanks!

[1/1] regulator: fan53555: Add support for FAN53555BUC23X type
      https://git.kernel.org/broonie/regulator/c/e739acbe05b0

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark