On Mon, 2012-11-26 at 15:37 +0000, Vasily Khoruzhick wrote: > On Thu, Nov 1, 2012 at 8:58 PM, Pawel Moll <pawel.moll@xxxxxxx> wrote: > > LEDs are often controlled by writing to memory mapped > > register. This patch adds: > > > > 1. Generic functions for platform code and drivers to create > > class device for LEDs controlled by arbitrary bit masks. > > The control register value is read, modified by logic AND > > and OR operations with respective mask and written back. > > > > 2. A platform driver for simple use case when one or more LED > > are controlled by consecutive bits in a register pointed > > at by the platform device's memory resource. It can be > > particularly useful for MFD cells being part of an other > > device. > > This MMIO controls some latch (or whatever) which is actually GPIO. > So implementing generic GPIO MMIO driver and using leds-gpio on top of > it appears to be a better solution for me. I won't argue that it is doable - I don't even have to implement the MMIO GPIO driver, because my MFD already has a set of pseudo-GPIO lines and extending those won't be a problem at all an I'll do exactly that if there is no other choice. But at the same time I hope you would agree that my_code->gpio_controller->gpio_led_description->register_device chain is longer than my_code->mmio_led one if you want to add a single "status" led for your little board ;-). I don't event mention that at least couple of the existing drivers follow the same "MMIO pattern" blindly. Nevertheless I'd really like to hear from the maintainers... Thanks! Paweł -- To unsubscribe from this list: send the line "unsubscribe linux-leds" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
