diff options
author | Gabriel Fernandez <gabriel.fernandez@foss.st.com> | 2022-05-16 10:05:57 +0300 |
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committer | Stephen Boyd <sboyd@kernel.org> | 2022-05-21 07:07:49 +0300 |
commit | 83ce0357dcb7fc7270fcb2c5cfea420085b8770e (patch) | |
tree | 8e5f9a8a6f094fc2e39cf35f5a7596dde841e369 /drivers/clk/stm32/clk-stm32-core.c | |
parent | ffa2d04d859e99d69d0c89d3dc50067022544354 (diff) | |
download | linux-83ce0357dcb7fc7270fcb2c5cfea420085b8770e.tar.xz |
clk: stm32mp13: add safe mux management
Some muxes need to set a the safe position when clock is off.
Signed-off-by: Gabriel Fernandez <gabriel.fernandez@foss.st.com>
Link: https://lore.kernel.org/r/20220516070600.7692-12-gabriel.fernandez@foss.st.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
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) |