[PATCH v2] iio: adc: stm32-dfsdm: add id registers support

[Jonathan Cameron]

On Thu, 5 Jan 2023 13:53:30 +0100
Olivier Moysan <olivier.moysan at foss.st.com> wrote:

> Add support of identification registers to STM32 DFSDM
> to allow hardware capabilities discovery and configuration check.
> The number of filters and channels, are read from registers,
> when they are available.
> 
> Signed-off-by: Olivier Moysan <olivier.moysan at foss.st.com>
One minor thing inline. I'll tweak it whilst applying.


Applied with that tweak to the togreg branch of iio.git and pushed out
as testing for 0-day etc to look at it.

Thanks,

Jonathan

> ---
> Changes in v2:
> - Add and update comments
> - Remove useless masks



> diff --git a/drivers/iio/adc/stm32-dfsdm.h b/drivers/iio/adc/stm32-dfsdm.h
> index 4afc1f528b78..b64cfb42c549 100644
> --- a/drivers/iio/adc/stm32-dfsdm.h
> +++ b/drivers/iio/adc/stm32-dfsdm.h
> @@ -13,25 +13,29 @@

...

>  /*
> @@ -231,6 +235,28 @@
>  #define DFSDM_AWCFR_AWHTF_MASK	GENMASK(15, 8)
>  #define DFSDM_AWCFR_AWHTF(v)	FIELD_PREP(DFSDM_AWCFR_AWHTF_MASK, v)
>  
> +/*
> + * Identification register definitions
> + */
> +#define DFSDM_HWCFGR		0x7F0
> +#define DFSDM_VERR		0x7F4
> +#define DFSDM_IPIDR		0x7F8
> +#define DFSDM_SIDR		0x7FC
> +
> +/* HWCFGR: Hardware configuration register */
> +#define DFSDM_HWCFGR_NBT_SHIFT	0

The _SHIFT macros don't add anything useful over using
the _MASK ones directly.  So drop them.

> +#define DFSDM_HWCFGR_NBT_MASK	GENMASK(7, 0)
> +#define DFSDM_HWCFGR_NBF_SHIFT	8
> +#define DFSDM_HWCFGR_NBF_MASK	GENMASK(15, 8)
> +
> +/* VERR: Version register */
> +#define DFSDM_VERR_MINREV_SHIFT	0
> +#define DFSDM_VERR_MINREV_MASK	GENMASK(3, 0)
> +#define DFSDM_VERR_MAJREV_SHIFT	4
> +#define DFSDM_VERR_MAJREV_MASK	GENMASK(7, 4)
> +
> +#define STM32MP15_IPIDR_NUMBER	0x00110031
> +
>  /* DFSDM filter order  */
>  enum stm32_dfsdm_sinc_order {
>  	DFSDM_FASTSINC_ORDER, /* FastSinc filter type */