Hello Everyone, On 14 May 2014 17:09, Naveen Krishna Chatradhi <ch.naveen@xxxxxxxxxxx> wrote: > exynos_drm_init() does probing of various drivers like dp_panel, > hdmi, fimd, mixer, etc in an order and finally binds them together. > > Some of the drm devices (Eg: dp_panel) try to do regulator_get() > and enable few supplies during their probe. > Chances are that, these devices may get probed before the respective > supply/PMIC is hooked. In such cases, dp_panel would continue with > "dummy regulator". Which is not what the system wants. > > Lets give the core connectivity and regulators modules some time > to hookup the supplies before Exynos DRM devices comes into picture. > > Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@xxxxxxxxxxx> > --- > This change is proposed after > 1. Discussing with I2C/SPI & DMA subsystem maintainers and Others > @ https://lkml.org/lkml/2014/5/9/333 > Trying to change the I2C, SPI and DMA drivers as subsys_initcall() > Which was strictly opposed, as a flaw was found in DRM subsystem. > > 2. -EPROBE_DEFER won't work well with the current sequency of > platform_driver_register()s in exynos_drm_init() > > 3. bridge_panel mechanism is under RFC and no conclusions were drawn yet. > > We should be able to probe each DRM device independently and let PROBE_DEFER > take care of dependencies. But, this could cause lot of bootup time. > > late_initcall() of DRM works well and fixes all the above issues for now. > Kindly suggest, if an alternative/better mechanism is out there. > > Thanks, > drivers/gpu/drm/exynos/exynos_drm_drv.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c > index 4cef88f..78c185a 100644 > --- a/drivers/gpu/drm/exynos/exynos_drm_drv.c > +++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c > @@ -692,7 +692,7 @@ static void exynos_drm_exit(void) > platform_driver_unregister(&exynos_drm_platform_driver); > } > > -module_init(exynos_drm_init); > +late_initcall(exynos_drm_init); > module_exit(exynos_drm_exit); > > MODULE_AUTHOR("Inki Dae <inki.dae@xxxxxxxxxxx>"); Kindly, show some light on this change. Also adding more reviewers. > -- > 1.7.9.5 > -- 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
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