On Mon, 2011-02-28 at 23:42 -0600, Semwal, Sumit wrote: > On Mon, Feb 28, 2011 at 9:33 PM, Tomi Valkeinen <tomi.valkeinen@xxxxxx> wrote: > > On Mon, 2011-02-28 at 09:02 -0600, Semwal, Sumit wrote: > >> Provide a function in pdata to allow dss submodules to check if a given > >> clock is available on a platform as an optional clock. > >> > >> Signed-off-by: Senthilvadivu Guruswamy <svadivu@xxxxxx> > >> (based on implementation from Senthil) > >> > >> Signed-off-by: Sumit Semwal <sumit.semwal@xxxxxx> > >> --- > >> arch/arm/mach-omap2/display.c | 20 ++++++++++++++++++++ > >> arch/arm/plat-omap/include/plat/display.h | 2 ++ > >> 2 files changed, 22 insertions(+), 0 deletions(-) > >> > >> diff --git a/arch/arm/mach-omap2/display.c b/arch/arm/mach-omap2/display.c > >> index 5ab6a74..9f4f862 100644 > >> --- a/arch/arm/mach-omap2/display.c > >> +++ b/arch/arm/mach-omap2/display.c > >> @@ -42,6 +42,25 @@ static struct omap_device_pm_latency omap_dss_latency[] = { > >> }, > >> }; > >> > >> +static bool opt_clock_available(const char *clk_role) > >> +{ > >> + int i; > >> + struct omap_hwmod *oh; > >> + > >> + /* opt_clks are always associated with dss hwmod */ > >> + oh = omap_hwmod_lookup("dss_core"); > >> + if (!oh) { > >> + pr_err("Could not look up dss_core.\n"); > >> + return -ENODEV; > > > > The function returns a bool. Perhaps the lookup would be better done in > > omap_display_init(), and stored in a static variable. > Yes; I guess I should go with your earlier suggestion - of keeping > this 'oh' as part of pdata, and then use it here. I don't think it needs to be part of pdata. It's internal to this file, and if I'm not mistaken, omap_display_init() is called just once from the current board file. Thus the data could as well be stored in a static variable. > > Or if it's clear that this should never happen, BUG_ON(!oh); > Well, multiple people have 'frowned' upon using BUG_ON in dss - > especially because some people might still want their kernel to keep > working despite a display failure? Yes, BUG is an easy, not good, way out =). Tomi -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html