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Subject: Re: [PATCH] regmap: Add function check before called format_val
From: Henry Chen <HenryC.Chen@mediatek.com>
To: Daniel Kurtz <djkurtz@chromium.org>
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On Wed, 2015-08-12 at 22:20 +0800, Daniel Kurtz wrote:

> 
> Since I didn't see it elsewhere in this discussion, I'll point out
> that the "regression" here was introduced by commit [0], which added
> the call to map->format.format_val from regmap_bulk_read() when
> map->bus == NULL.
> 
> [0] commit 15b8d2c41fe5839582029f65c5f7004db451cc2b
>   Author: Arun Chandran <achandran@mvista.com>
>   regmap: Fix regmap_bulk_read in BE mode
> 
> Perhaps the easiest work around to unbreak v4.2 is, as Henry mentions,
> for mtk_pmic_wrap to define its own regmap_bus, with .read() &
> .write() handlers.  This way they will inherit the default built-in
> format_val() from the regmap core.
> 
> Making mtk_pmic-wrap into a regmap_bus makes a bit of sense
> architecturally, too, since it is essentially just a bus for accessing
> the registers of an off-chip PMIC.  The CPU sees a platform bus, but
> the registers of the remote PMIC are accessed over a dedicated SPI
> bus.
> 
> WDYT?
> 
> Henry, can you try to implement this?

Hi Daniel,
I can try to create a regmap_bus for pmic wrap. But I'm not sure if it
was the good solution for this problem.

Hi Mark,
Sorry, I'm afraid that I cannot do this right on init as you said last
time. What do you think about regmap_bus, can you accept that way?

Thanks,
Henry
> 
> Thanks,
> -Dan