On 12/01/15 14:05, Mark Brown wrote: > On Mon, Jan 12, 2015 at 12:02:21PM +0200, Roger Quadros wrote: >> +Mark with correct id. > > Please fix your mail client to word wrap within paragraphs, it amkes > your mail more legible. Fixed now. Thanks for pointing out. > >>> The problem here is we can't use regmap_update_bits() because we need to write a 1 to the DONE bit to clear it and _regmap_update_bits() doesn't allow us to do that because of commit >>> d91e8db2c3bb regmap: Suppress noop writes in regmap_update_bits() >>> >>> Is reverting it going to cause other issues? If yes then can we have a flag to specify forced update? > > The usual thing to do here is an explicit write clearing the latch, > either immediately after setting it or immediately before setting it. > If the register is marked as volatile and the hardware doesn't read back > the latched state that also does the trick. > How does this work if driver has access to only 1 bit that can only be written with 1 to clear a condition? Writing a 0 is no-op. It can read back 0 or 1 depending on the condition. I didn't understand the volatile trick :P. cheers, -roger -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
