[PATCH v2 1/5] spi: add spi_optimize_message() APIs

[Jonathan Cameron]

On Mon, 19 Feb 2024 16:33:18 -0600
David Lechner <dlechner at baylibre.com> wrote:

> This adds a new spi_optimize_message() function that can be used to
> optimize SPI messages that are used more than once. Peripheral drivers
> that use the same message multiple times can use this API to perform SPI
> message validation and controller-specific optimizations once and then
> reuse the message while avoiding the overhead of revalidating the
> message on each spi_(a)sync() call.
> 
> Internally, the SPI core will also call this function for each message
> if the peripheral driver did not explicitly call it. This is done to so
> that controller drivers don't have to have multiple code paths for
> optimized and non-optimized messages.
> 
> A hook is provided for controller drivers to perform controller-specific
> optimizations.
> 
> Suggested-by: Martin Sperl <kernel at martin.sperl.org>
> Link: https://lore.kernel.org/linux-spi/39DEC004-10A1-47EF-9D77-276188D2580C@martin.sperl.org/
> Signed-off-by: David Lechner <dlechner at baylibre.com>

Very nice.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron at huawei.com>