[PATCH 2/5] clk: sunxi-ng: gate: Support common pre-dividers
From: Chen-Yu Tsai <hidden>
Date: 2017-02-14 03:35:37
Also in:
linux-clk, lkml
Subsystem:
arm/allwinner sunxi soc support, common clk framework, the rest · Maintainers:
Chen-Yu Tsai, Jernej Skrabec, Samuel Holland, Michael Turquette, Stephen Boyd, Linus Torvalds
Some clock gates have a pre-divider between the source input and the gate itself. A notable example is the HSIC 12 MHz clock found on the A83T, which has the 24 MHz main oscillator as its input, and a /2 pre-divider. Signed-off-by: Chen-Yu Tsai <redacted> --- drivers/clk/sunxi-ng/ccu_gate.c | 47 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+)
diff --git a/drivers/clk/sunxi-ng/ccu_gate.c b/drivers/clk/sunxi-ng/ccu_gate.c
index 8a81f9d4a89f..cd069d5da215 100644
--- a/drivers/clk/sunxi-ng/ccu_gate.c
+++ b/drivers/clk/sunxi-ng/ccu_gate.c@@ -75,8 +75,55 @@ static int ccu_gate_is_enabled(struct clk_hw *hw) return ccu_gate_helper_is_enabled(&cg->common, cg->enable); } +static unsigned long ccu_gate_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct ccu_gate *cg = hw_to_ccu_gate(hw); + unsigned long rate = parent_rate; + + if (cg->common.features & CCU_FEATURE_ALL_PREDIV) + rate /= cg->common.prediv; + + return rate; +} + +static long ccu_gate_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + struct ccu_gate *cg = hw_to_ccu_gate(hw); + int div = 1; + + if (cg->common.features & CCU_FEATURE_ALL_PREDIV) + div = cg->common.prediv; + + if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) { + unsigned long best_parent = rate; + + if (cg->common.features & CCU_FEATURE_ALL_PREDIV) + best_parent *= div; + *prate = clk_hw_round_rate(clk_hw_get_parent(hw), best_parent); + } + + return *prate / div; +} + +static int ccu_gate_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + /* + * We must report success but we can do so unconditionally because + * clk_factor_round_rate returns values that ensure this call is a + * nop. + */ + + return 0; +} + const struct clk_ops ccu_gate_ops = { .disable = ccu_gate_disable, .enable = ccu_gate_enable, .is_enabled = ccu_gate_is_enabled, + .round_rate = ccu_gate_round_rate, + .set_rate = ccu_gate_set_rate, + .recalc_rate = ccu_gate_recalc_rate, };
--
2.11.0