Re: [PATCH] iio: adc: ltc2309: Add read delay support for LTC2305

[Andy Shevchenko]

On Fri, Mar 27, 2026 at 11:41:59AM +0800, Carlos Jones Jr wrote:
> The LTC2305 requires a minimum 1.6μs delay between the I2C write
> operation (channel selection) and the subsequent read operation to
> allow the chip to process the command and prepare the result. While
> not explicitly documented in the datasheet, this timing requirement
> was identified by the hardware designer as necessary for reliable
> operation.
> 
> This extends the existing LTC2305 support (commit 8625d418d24b
> ("iio: adc: ltc2309: add support for ltc2305")) with the missing
> inter-transaction delay.
> 
> Add a read_delay_us field to chip_info to support chip-specific timing
> requirements. Use fsleep() to implement the delay, with LTC2305 set to
> 2μs (1.6μs requirement rounded up). LTC2309 does not require additional
> delay beyond inherent I2C bus timing.

> Also optimize chip_info structure with __counted_by_ptr() annotation
> and field reordering to minimize padding.

This should be a separate patch.
Please, always split the change to logical pieces.

-- 
With Best Regards,
Andy Shevchenko