Re: [PATCH v10 2/8] mfd: simple-mfd-i2c: specify max_register

From: Lee Jones <lee@kernel.org>
To: Alex Elder <elder@riscstar.com>
Cc: lgirdwood@gmail.com, broonie@kernel.org,
	alexandre.belloni@bootlin.com, robh@kernel.org,
	krzk+dt@kernel.org, conor+dt@kernel.org, mat.jonczyk@o2.pl,
	dlan@gentoo.org, paul.walmsley@sifive.com, palmer@dabbelt.com,
	aou@eecs.berkeley.edu, alex@ghiti.fr, linux.amoon@gmail.com,
	troymitchell988@gmail.com, guodong@riscstar.com,
	linux-rtc@vger.kernel.org, devicetree@vger.kernel.org,
	linux-riscv@lists.infradead.org, spacemit@lists.linux.dev,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v10 2/8] mfd: simple-mfd-i2c: specify max_register
Date: Thu, 31 Jul 2025 14:41:48 +0100	[thread overview]
Message-ID: <20250731134148.GI1049189@google.com> (raw)
In-Reply-To: <e3cd0e11-e516-4cf6-b8f8-5cf2b5a236a4@riscstar.com>

On Thu, 31 Jul 2025, Alex Elder wrote:

> On 7/31/25 8:18 AM, Lee Jones wrote:
> > 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@riscstar.com>
> > > Suggested-by: Lee Jones <lee@kernel.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?
> 
> I LOVE this suggestion.  I will send v11 shortly and it will
> be very much like v6 (or something like that).
> 
> > [0] Beers on me for sending you down this path!
> 
> I'm looking forward to seeing you again, beer or not.

Likewise!  =:-)

-- 
Lee Jones [李琼斯]