On Wed, Jan 16, 2013 at 04:01:20PM +0100, Rafael J. Wysocki wrote: > On Wednesday, January 16, 2013 07:20:54 AM Mika Westerberg wrote: > > On Wed, Jan 16, 2013 at 12:59:17AM +0100, Rafael J. Wysocki wrote: > > > On Monday, January 14, 2013 04:46:26 PM Mika Westerberg wrote: > > > > We are starting to see traditional SoC peripherals also in the x86 world, > > > > things like UART, I2C and SPI controllers that might already have a working > > > > device driver. These drivers typically take advantage of the Linux clk > > > > framework to control and retrieve information about the peripheral clock. > > > > > > > > There hasn't been a standard way on x86 to pass the clock rate from > > > > whatever configuration system is used to the driver, but instead different > > > > variations have emerged, like adding this information to the platform data. > > > > > > > > In order to use the standard Linux way we enable the common clk subsystem > > > > also on x86. This allows us to re-use the drivers with little or no > > > > modification wrt. clock API usage. > > > > > > > > This patch was originally proposed by Mark Brown. > > > > > > Are there any side effects of selecting COMMON_CLK by an arch and if so then > > > what are they? > > > > Selecting COMMON_CLK also selects HAVE_CLK, so drivers that are dependent > > on that option become available when you run make config. > > Well, that's not very nice. Do you know how many of them there are? There are few. I tried how many I get on my config and there were 9 new questions with 'make oldconfig'. Grepping (if I did it correctly) reveals: % git grep 'depends .*HAVE_CLK' -- '*/Kconfig' | wc -l 27 > Distros often build all drivers available regardless of whether or not they > are going to be used and it would be kind of wasteful for them to build drivers > that aren't even going to work. If a driver depends only on HAVE_CLK and doesn't work everywhere, there is a problem in that particular driver and its Kconfig options (some dependencies are missing). These drivers should be fixed. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
