diff options
Diffstat (limited to 'drivers/clk/stm32/clk-stm32-core.c')
| -rw-r--r-- | drivers/clk/stm32/clk-stm32-core.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/drivers/clk/stm32/clk-stm32-core.c b/drivers/clk/stm32/clk-stm32-core.c index e5a22bb09495..45a279e73779 100644 --- a/drivers/clk/stm32/clk-stm32-core.c +++ b/drivers/clk/stm32/clk-stm32-core.c @@ -495,6 +495,54 @@ static int clk_stm32_composite_is_enabled(struct clk_hw *hw) return stm32_gate_is_enabled(composite->base, composite->clock_data, composite->gate_id); } +#define MUX_SAFE_POSITION 0 + +static int clk_stm32_has_safe_mux(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + const struct stm32_mux_cfg *mux = &composite->clock_data->muxes[composite->mux_id]; + + return !!(mux->flags & MUX_SAFE); +} + +static void clk_stm32_set_safe_position_mux(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + + if (!clk_stm32_composite_is_enabled(hw)) { + unsigned long flags = 0; + + if (composite->clock_data->is_multi_mux) { + struct clk_hw *other_mux_hw = NULL; + + other_mux_hw = composite->clock_data->is_multi_mux(hw); + + if (!other_mux_hw || clk_stm32_composite_is_enabled(other_mux_hw)) + return; + } + + spin_lock_irqsave(composite->lock, flags); + + stm32_mux_set_parent(composite->base, composite->clock_data, + composite->mux_id, MUX_SAFE_POSITION); + + spin_unlock_irqrestore(composite->lock, flags); + } +} + +static void clk_stm32_safe_restore_position_mux(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + int sel = clk_hw_get_parent_index(hw); + unsigned long flags = 0; + + spin_lock_irqsave(composite->lock, flags); + + stm32_mux_set_parent(composite->base, composite->clock_data, composite->mux_id, sel); + + spin_unlock_irqrestore(composite->lock, flags); +} + static void clk_stm32_composite_gate_endisable(struct clk_hw *hw, int enable) { struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); @@ -516,6 +564,9 @@ static int clk_stm32_composite_gate_enable(struct clk_hw *hw) clk_stm32_composite_gate_endisable(hw, 1); + if (composite->mux_id != NO_STM32_MUX && clk_stm32_has_safe_mux(hw)) + clk_stm32_safe_restore_position_mux(hw); + return 0; } @@ -527,6 +578,9 @@ static void clk_stm32_composite_gate_disable(struct clk_hw *hw) return; clk_stm32_composite_gate_endisable(hw, 0); + + if (composite->mux_id != NO_STM32_MUX && clk_stm32_has_safe_mux(hw)) + clk_stm32_set_safe_position_mux(hw); } static void clk_stm32_composite_disable_unused(struct clk_hw *hw) |