Re: [RFC/RFT PATCH 1/3] Input: ad7879 - convert to use regmap

[Michael Hennerich <michael.hennerich@analog.com>]

On 18.02.2017 00:31, Dmitry Torokhov wrote:
> Instead of rolling our own infrastructure to provide uniform access to I2C
> and SPI buses, let's switch to using regmap.
>
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---
>
> Michael,
>
> I am a bit (actually a lot) confused how this driver was working with SPI
> and Blackfin, which is, as far as I understand, little-endian, because from
> my reading of the spec the data on wire is big-endian. If this is not
> correct we need to change spi regmap config to be:
>
> static const struct regmap_config ad7879_spi_regmap_config = {
> 	.reg_bits = 16,
> 	.val_bits = 16,
> 	.max_register = 15,
> 	.read_flag_mask = AD7879_CMD_MAGIC | AD7879_CMD_READ,
> 	.write_flag_mask = AD7879_CMD_MAGIC,
> 	.reg_format_endian_default = REGMAP_ENDIAN_LITTLE,
> 	.val_format_endian_default = REGMAP_ENDIAN_LITTLE,
> };
>
> Also, the original ad7879_spi_xfer was funky to tell the least. We
> allocated n+2 spi_transfer structures, then smashed the beginning of the
> first one with u16 command, then basically "restored" it???
>
> Anyway, if you could try it out (and fix ;) ), that would be great.

Hi Dimitry,

Thanks for doing this.
Overall looks great, but i definitely need to test this.
Your right this xfer functions looks awkward.
I'll review and get back to you.



-- 
Greetings,
Michael

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