On 12 October 2013 11:12, Tomasz Figa <t.figa@xxxxxxxxxxx> wrote: > On Saturday 12 of October 2013 04:28:51 Tomasz Figa wrote: >> [Fixing incorrent mail addresses and dropping the old DT ML.] >> >> On Saturday 12 of October 2013 04:22:04 Tomasz Figa wrote: >> > Hi Naveen, >> > >> > On Friday 11 of October 2013 16:56:54 Naveen Krishna Chatradhi wrote: >> > > The exynos5 i2c clock is based on a fixed 66 MHz peripheral clock, and >> > > therefore is completely independent of the cpu frequency. >> > > Thus, registering for a CPU freq notifier is very wasteful. >> > > >> > > This patch modifes the code such that, i2c bus registers to >> > > cpu_freq_transition only for non Exynos SoCs. >> > > >> > > This change should save a bunch of cpufreq transitions calls >> > > which does not apply to exynos SoCs. >> > >> > The idea is fine, although... >> > >> > > Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@xxxxxxxxxxx> >> > > --- >> > > drivers/i2c/busses/i2c-s3c2410.c | 4 ++-- >> > > 1 file changed, 2 insertions(+), 2 deletions(-) >> > > >> > > diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c >> > > index cab1c91..d062fa7 100644 >> > > --- a/drivers/i2c/busses/i2c-s3c2410.c >> > > +++ b/drivers/i2c/busses/i2c-s3c2410.c >> > > @@ -123,7 +123,7 @@ struct s3c24xx_i2c { >> > > struct s3c2410_platform_i2c *pdata; >> > > int gpios[2]; >> > > struct pinctrl *pctrl; >> > > -#ifdef CONFIG_CPU_FREQ >> > > +#if defined(CONFIG_CPU_FREQ) && !defined(CONFIG_ARCH_EXYNOS) >> > >> > ...this is not a good coding practice, especially when already having >> > multiplatform kernels in sight. >> > >> > The best way would be to check on which SoC we are running at runtime, >> > but since this might need changing a lot of code, then at least I would >> > change this from !defined(EXYNOS) to defined(S3C24XX), so it is not being >> > compiled in when S3C24XX support is not enabled and if it's enabled then >> > the notifier will be registered as a safe fallback that will run correctly >> > on all platforms. > > Actually you can simply check for CONFIG_CPU_FREQ_S3C24XX here. sure, this makes it more meaningful. will make the modifications and resubmit. > > Best regards, > Tomasz > -- Shine bright, (: Nav :) -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html