Re: [PATCH 1/4] regulator: dt-bindings: Add Silergy SYR82X allowed modes

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:

New issues:
- [Medium] Missing of_map_mode callback in fan53555 driver renders DT mode constants non-functional.
- [Low] Brand name misspelled in the newly added header file comment.

Pre-existing issues:
- [High] fan53555_set_mode() corrupts the voltage or enable register instead of changing the mode for multiple non-default variants.
--

--- Patch [1]: [PATCH 1/4] regulator: dt-bindings: Add Silergy SYR82X allowed modes ---
commit 17c0df18a13c2c0dbee697655aab8c718df5c959
Author: Victor Krawiec <victor.krawiec@arturia.com>

regulator: dt-bindings: Add Silergy SYR82X allowed modes
    
Make the PWM mode configurable from devicetree. Some boards require forced
PWM mode to keep the supply ripple within acceptable limits under light
load conditions.

> diff --git a/include/dt-bindings/regulator/silergy,syr82x.h b/include/dt-bindings/regulator/silergy,syr82x.h
> new file mode 100644
> index 0000000000000..6d4aa86bb5c1d
> --- /dev/null
> +++ b/include/dt-bindings/regulator/silergy,syr82x.h
> @@ -0,0 +1,20 @@
> +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
> +/*
> + * Copyright (c) 2026 Arturia - All rights reserved.
> + *
> + * Device Tree binding constants for the Sylergy SYR827 and SYR828 PMIC regulators

[Severity: Low]
This isn't a bug, but there is a typo here ("Sylergy" instead of "Silergy").

> + */
> +
> +#ifndef _DT_BINDINGS_REGULATOR_SYR82X_H
> +#define _DT_BINDINGS_REGULATOR_SYR82X_H
> +
> +/*
> + * Constants to specify regulator modes in device tree for SYR82X regulators
> + * SYR82X_REGULATOR_MODE_FORCE_PWM:	Force fixed PWM mode
> + * SYR82X_REGULATOR_MODE_AUTO:		Allow auto-PFM mode during light load
> + */
> +
> +#define SYR82X_REGULATOR_MODE_FORCE_PWM	1
> +#define SYR82X_REGULATOR_MODE_AUTO	2

[Severity: Medium]
Will these constants actually be parsed by the regulator core?

Looking at the driver handling the SYR82x regulators, it appears to lack the
.of_map_mode callback:

drivers/regulator/fan53555.c:fan53555_regulator_register() {
	...
	rdesc->enable_time = di->enable_time;
	rdesc->owner = THIS_MODULE;

	rdev = devm_regulator_register(di->dev, &di->desc, config);
	...
}

Without an of_map_mode callback, won't the regulator core fail to translate
these device tree mode constants, leaving the forced PWM mode non-functional?

[Severity: High]
This is a pre-existing issue, but while reviewing the mode support for this
hardware I noticed that fan53555_set_mode() might be corrupting registers:

drivers/regulator/fan53555.c:fan53555_set_mode() {
	...
	case REGULATOR_MODE_NORMAL:
		regmap_update_bits(rdev->regmap, di->vol_reg, di->mode_mask, 0);
		break;
	...
}

Does this incorrectly clear the mode mask on di->vol_reg instead of
di->mode_reg?

For variants like FAN53526_VENDOR_TCS where these point to different
registers, could this drop the voltage or disable the regulator entirely
when changing to normal mode?

> +
> +#endif

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260715155141.128601-1-victor.krawiec@arturia.com?part=1