[U-Boot] [PATCH v3] dm: spi: Read default speed and mode values from DT

[Jagan Teki]

On Mon, Jan 28, 2019 at 2:37 PM Patrick Delaunay
<patrick.delaunay at st.com> wrote:
>
> This patch update the behavior introduced by
> commit 96907c0fe50a ("dm: spi: Read default speed and mode values from DT")
>
> In case of DT boot, don't read default speed and mode for SPI from
> CONFIG_* but instead read from DT node. This will make sure that boards
> with multiple SPI/QSPI controllers can be probed at different
> bus frequencies and SPI modes.
>
> DT values will be always used when available (full DM support of
> SPI slave with available DT node) even if speed and mode are requested;
> for example in splash screen support (in splash_sf_read_raw)
> or in SPL boot (in spl_spi_load_image).
> The caller of spi_get_bus_and_cs() no more need to force speed=0.
>
> But the current behavior don't change if the SPI slave is not
> present (device with generic driver is created automatically)
> or if platdata is used (CONFIG_OF_PLATDATA).
>
>
> Signed-off-by: Patrick Delaunay <patrick.delaunay at st.com>
> ---
>
> Changes in v3:
>     - complete rework of the patch-set to avoid regression
>
> Changes in v2:
>     - use variables to avoid duplicated code
>
>  README                   | 3 +++
>  cmd/sf.c                 | 3 +--
>  common/spl/spl_spi.c     | 2 ++
>  drivers/spi/spi-uclass.c | 4 +++-
>  include/spi.h            | 9 +++++----
>  5 files changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/README b/README
> index 17d56b8..f7fe74f 100644
> --- a/README
> +++ b/README
> @@ -2184,6 +2184,9 @@ The following options need to be configured:
>                 CONFIG_SF_DEFAULT_MODE          (see include/spi.h)
>                 CONFIG_SF_DEFAULT_SPEED         in Hz
>
> +               In case of DT boot, SPI don't read default speed and mode
> +               from CONFIG_*, but from platdata values computed from available
> +               DT node

This has to update in Kconfig help info.