Re: [PATCH v4 6/8] media: imx274: add helper function to fill a reg_8 table chunk

From: Luca Ceresoli
Date: Wed Jun 27 2018 - 05:09:47 EST


Hi Sakari,

On 26/06/2018 14:20, Sakari Ailus wrote:
> Hi Luca,
>
> On Mon, Jun 11, 2018 at 01:35:37PM +0200, Luca Ceresoli wrote:
>> Tables of struct reg_8 are used to simplify multi-byte register
>> assignment. However filling these snippets with values computed at
>> runtime is currently implemented by very similar functions doing the
>> needed shift & mask manipulation.
>>
>> Replace all those functions with a unique helper function to fill
>> reg_8 tables in a simple and clean way.
>
> What's the purpose of writing these registers as multiple IÂC writes, when
> this can be done as a single write (i.e. the address followed by two or
> three octets of data)?

Good point. The for loops applying the register values (the lines just
after those changed by my patch) defuse the regmap bulk write capability.

I guess this could be improved not filling any table, but directly
calling regmap_bulk_write(), passing the u16 or u32 register value with
proper endianness. No tables, less code. This would replace the present
patch with a shorter and more effective one. Is it what you was suggesting?

I'll try that.
--
Luca