From 8b95d1ce3300c411728954473316bd04d0ba9883 Mon Sep 17 00:00:00 2001 From: Russ Dill Date: Tue, 4 Sep 2018 12:19:35 +0530 Subject: clk: Add functions to save/restore clock context en-masse Deep enough power saving mode can result into losing context of the clock registers also, and they need to be restored once coming back from the power saving mode. Hence add functions to save/restore clock context. Signed-off-by: Keerthy Signed-off-by: Russ Dill Acked-by: Tony Lindgren Signed-off-by: Tero Kristo --- include/linux/clk-provider.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/linux/clk-provider.h') diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index 08b1aa70a38d..df7379da6269 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -119,6 +119,11 @@ struct clk_duty { * Called with enable_lock held. This function must not * sleep. * + * @save_context: Save the context of the clock in prepration for poweroff. + * + * @restore_context: Restore the context of the clock after a restoration + * of power. + * * @recalc_rate Recalculate the rate of this clock, by querying hardware. The * parent rate is an input parameter. It is up to the caller to * ensure that the prepare_mutex is held across this call. @@ -223,6 +228,8 @@ struct clk_ops { void (*disable)(struct clk_hw *hw); int (*is_enabled)(struct clk_hw *hw); void (*disable_unused)(struct clk_hw *hw); + int (*save_context)(struct clk_hw *hw); + void (*restore_context)(struct clk_hw *hw); unsigned long (*recalc_rate)(struct clk_hw *hw, unsigned long parent_rate); long (*round_rate)(struct clk_hw *hw, unsigned long rate, -- cgit From 435365485f40cf12747d1daa2253a4f4b46b8148 Mon Sep 17 00:00:00 2001 From: Keerthy Date: Tue, 4 Sep 2018 12:19:36 +0530 Subject: clk: clk: Add clk_gate_restore_context function The clock gate restore context function enables or disables the gate clocks based on the enable_count. This is done in cases where the clock context is lost and based on the enable_count the clock either needs to be enabled/disabled. Signed-off-by: Keerthy Acked-by: Tony Lindgren Signed-off-by: Tero Kristo --- drivers/clk/clk.c | 19 +++++++++++++++++++ include/linux/clk-provider.h | 2 ++ 2 files changed, 21 insertions(+) (limited to 'include/linux/clk-provider.h') diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 8a0254a1c303..dd775771a7cc 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -923,6 +923,25 @@ static int clk_core_enable_lock(struct clk_core *core) return ret; } +/** + * clk_gate_restore_context - restore context for poweroff + * @hw: the clk_hw pointer of clock whose state is to be restored + * + * The clock gate restore context function enables or disables + * the gate clocks based on the enable_count. This is done in cases + * where the clock context is lost and based on the enable_count + * the clock either needs to be enabled/disabled. This + * helps restore the state of gate clocks. + */ +void clk_gate_restore_context(struct clk_hw *hw) +{ + if (hw->clk->core->enable_count) + hw->clk->core->ops->enable(hw); + else + hw->clk->core->ops->disable(hw); +} +EXPORT_SYMBOL_GPL(clk_gate_restore_context); + static int _clk_save_context(struct clk_core *clk) { struct clk_core *child; diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index df7379da6269..60c51871b04b 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -1018,5 +1018,7 @@ static inline void clk_writel(u32 val, u32 __iomem *reg) #endif /* platform dependent I/O accessors */ +void clk_gate_restore_context(struct clk_hw *hw); + #endif /* CONFIG_COMMON_CLK */ #endif /* CLK_PROVIDER_H */ -- cgit