Re: [PATCH] iio: adc: ti-ads7950: use spi_optimize_message()

[Andy Shevchenko <andriy.shevchenko@intel.com>]

On Sat, Apr 11, 2026 at 05:13:33PM -0500, David Lechner wrote:
> Use spi_optimize_message() to reduce CPU usage during buffered reads.
> 
> On hardware with support for SPI_CS_WORD, this reduced the CPU usage
> of the threaded interrupt by about 5%. On hardware without support, this
> should reduce CPU usage even more since it won't have to split the SPI
> transfers each time the interrupt handler is called.
> 
> The update_scan_mode callback hand to be moved to the buffer preenable
> callback since the SPI transfer mode can't be changed after
> spi_optimize_message() has been called. (The buffer postenable callback
> can't be used because it happens after the trigger is enabled, so the
> SPI message needs to be optimized before that.)
> 
> The indent of ti_ads7950_read_raw is changed since there is no longer
> anything else in the struct to align with since we removed
> ti_ads7950_update_scan_mode.

Some of the func() are mentioned w/o parentheses and I got lost which one is
which. Also callbacks usually mentioned as .callback() (with a leading dot).

The second paragraph doesn't tell me clearly if there is a behaviour change
from user perspective.

-- 
With Best Regards,
Andy Shevchenko