From aaf2c0fbbbb1ec56936e726eec6c253bc4bd469f Mon Sep 17 00:00:00 2001 From: Lokesh Vutla Date: Wed, 10 Jun 2015 14:56:24 +0530 Subject: [PATCH] ARM: OMAP2+: hwmod: add support for lock and unlock hooks Some IP blocks like RTC, needs an additional setting for writing to its registers. This is to prevent any spurious writes from changing the register values. This patch adds optional lock and unlock function pointers to the IP block's hwmod data. These unlock and lock function pointers are called by hwmod code before and after writing sysconfig registers. Signed-off-by: Lokesh Vutla [paul@pwsan.com: fixed indentation level to conform with the rest of the structure members] Reviewed-by: Paul Walmsley Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/omap_hwmod.c | 13 +++++++++++++ arch/arm/mach-omap2/omap_hwmod.h | 4 ++++ 2 files changed, 17 insertions(+) diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c index d78c12e7cb5e..2ceed3192f22 100644 --- a/arch/arm/mach-omap2/omap_hwmod.c +++ b/arch/arm/mach-omap2/omap_hwmod.c @@ -299,7 +299,20 @@ static void _write_sysconfig(u32 v, struct omap_hwmod *oh) /* Module might have lost context, always update cache and register */ oh->_sysc_cache = v; + + /* + * Some IP blocks (such as RTC) require unlocking of IP before + * accessing its registers. If a function pointer is present + * to unlock, then call it before accessing sysconfig and + * call lock after writing sysconfig. + */ + if (oh->class->unlock) + oh->class->unlock(oh); + omap_hwmod_write(v, oh, oh->class->sysc->sysc_offs); + + if (oh->class->lock) + oh->class->lock(oh); } /** diff --git a/arch/arm/mach-omap2/omap_hwmod.h b/arch/arm/mach-omap2/omap_hwmod.h index b5d27ec81610..13f390202c60 100644 --- a/arch/arm/mach-omap2/omap_hwmod.h +++ b/arch/arm/mach-omap2/omap_hwmod.h @@ -576,6 +576,8 @@ struct omap_hwmod_omap4_prcm { * @pre_shutdown: ptr to fn to be executed immediately prior to device shutdown * @reset: ptr to fn to be executed in place of the standard hwmod reset fn * @enable_preprogram: ptr to fn to be executed during device enable + * @lock: ptr to fn to be executed to lock IP registers + * @unlock: ptr to fn to be executed to unlock IP registers * * Represent the class of a OMAP hardware "modules" (e.g. timer, * smartreflex, gpio, uart...) @@ -600,6 +602,8 @@ struct omap_hwmod_class { int (*pre_shutdown)(struct omap_hwmod *oh); int (*reset)(struct omap_hwmod *oh); int (*enable_preprogram)(struct omap_hwmod *oh); + void (*lock)(struct omap_hwmod *oh); + void (*unlock)(struct omap_hwmod *oh); }; /** -- 2.20.1