linux-kernel - Re: [PATCH v10 2/8] mfd: simple-mfd-i2c: specify max

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Message-ID: <20250731131827.GG1049189@google.com>
Date: Thu, 31 Jul 2025 14:18:27 +0100
From: Lee Jones <lee@...nel.org>
To: Alex Elder <elder@...cstar.com>
Cc: lgirdwood@...il.com, broonie@...nel.org, alexandre.belloni@...tlin.com,
	robh@...nel.org, krzk+dt@...nel.org, conor+dt@...nel.org,
	mat.jonczyk@...pl, dlan@...too.org, paul.walmsley@...ive.com,
	palmer@...belt.com, aou@...s.berkeley.edu, alex@...ti.fr,
	linux.amoon@...il.com, troymitchell988@...il.com,
	guodong@...cstar.com, linux-rtc@...r.kernel.org,
	devicetree@...r.kernel.org, linux-riscv@...ts.infradead.org,
	spacemit@...ts.linux.dev, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v10 2/8] mfd: simple-mfd-i2c: specify max_register

On Sat, 26 Jul 2025, Alex Elder wrote:

> All devices supported by simple MFD use the same 8-bit register 8-bit
> value regmap configuration.  There is an option available for a device
> to specify a custom configuration, but no existing device uses it.
> 
> Rather than requiring a "full" regmap configuration to be provided to
> change only the max_register value, Lee Jones suggested allowing
> max_register to be specified in the simple_mfd_data structure.  The
> 8-bit register 8-bit configuration is still used by default, but
> max_register is also applied if it is non-zero.
> 
> If both regmap_config and max_register are provided, the max_register
> field in the regmap_config structure is ignored.
> 
> Signed-off-by: Alex Elder <elder@...cstar.com>
> Suggested-by: Lee Jones <lee@...nel.org>
> ---
> v10: - Rename simple_regmap_config() -> simple_regmap_config_get()
>      - Introduce simple_regmap_config_put() to free regmap_config
> 
>  drivers/mfd/simple-mfd-i2c.c | 45 ++++++++++++++++++++++++++++++++----
>  drivers/mfd/simple-mfd-i2c.h |  5 +---
>  2 files changed, 41 insertions(+), 9 deletions(-)

This has gone from an in-function 11 line change to 50 lines and the
inclusion of 2 new functions.  As much as I _really_ appreciate the time
and effort you have put into this [0], the added complexity being added
here doesn't sit right with me.  How would you like to go back to your
v4 idea of providing a bespoke regmap_config for for device?

[0] Beers on me for sending you down this path!

-- 
Lee Jones [李琼斯]