On 10/18/11 14:43, Ricardo Ribalda Delgado wrote: > Hello Jonathan > > First of all, thanks for your messages :). > >> To make my point about these functions being more complex than needed >> in more detail.... >> >> If this were two functions and you drop the zero and 1 mask >> (which I'm not convinced make any sense. I've also killed the message. >> We both agree it is the wrong way to go, so post a patch fixing the i2c >> interface as well. > > Of course your functions are much more simpler and beautiful than the > fat one I wrote, no doubt about it :). Just three comments > > - Checking the one mask and the zero mask is the only way we have to > know if the chip is still there, The absense of that reply should > trigger an IO error or at least a retry. As you point out, the > zero/one mask is only violated on startup. I just wanted to make it > more risk free, but if you believe it is more clear that way, lets > remove it It's somewhat unconventional to verify the existence of a chip like this. Usually you assume that if it was there once it still is unless there is a very good reason to think otherwise. Worth doing an initial check in your spi_probe and indeed verify there against these known bits. No need to do it every time though. > > - I am not very fun of kmallocing data per write, specially when it is > part of the irq handler, and you expect this to be low latency. What > about allocating a buffer on init time, and use it with a mutex? That's absolutely fine and the right way to do it. You could poke it into the cma3000_accl_data then use the cachline aligned magic. Its is tiny so I doubt anyone will mind the overhead for the i2c side of things. > > -I dont like the push error message to the bottom, but that will mean > a rewrite of the cma3000 driver, shall I go for it? I would. Though probably worth getting Hemanth to say if he minds first given it's his driver! > > > Thanks again, and I will post the new version when you reply this :) > > -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
