>> >> On 28 of September 2010 10:40:42 Arun Murthy wrote: >> >> > The existing pwm based led and backlight driver makes use of the >> >> > pwm(include/linux/pwm.h). So all the board specific pwm drivers >> will >> >> > be exposing the same set of function name as in >> include/linux/pwm.h. >> >> > As a result build fails. >> >> >> >> Which build fails? One with multi-SoC support? Please be more >> specific. >> > Sure will add this in v2. >> > >> >> Could you clarify for the benefit of all, which specific issues you are >> trying to address with this patch series > 1. Now since all the pwm driver export same set of function(pwm_enable, pwm_disable,..), if it happens that there are two pwm driver enabled this > leads to re-declaration and results in build failure. The proper way to handle this would be to have a pwm core function, and let all the pwm > drivers register to the pwm core driver. > 2. The above scenario also occurs in place of multi-soc environment. Lets say OMAP has a pwm module and that is being used for primary lcd backlight > and twl has a backlight that is being used for controlling the charging led brightness. In this case there exists 2 pwm drivers and one pwm driver > will be used by pwm_bl.c and other by leds-pwm.c Speaking specifically of OMAP4, twl6030 supports multiple PWMs i.e for display/keypad backlight, charging led. But there should not be need for multiple drivers since twl6030-pwm should be able to support all these (currently it doesnot though). So there would single pwm_enable, pwm_disable exported and driver internally takes care configuring the correct PWM based on id. Would it not be similar situation for other hardware also. Thanks Hemanth
