xref: /openbmc/linux/drivers/clk/actions/owl-gate.c (revision aac28965)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // OWL gate clock driver
4 //
5 // Copyright (c) 2014 Actions Semi Inc.
6 // Author: David Liu <liuwei@actions-semi.com>
7 //
8 // Copyright (c) 2018 Linaro Ltd.
9 // Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
10 
11 #include <linux/clk-provider.h>
12 #include <linux/regmap.h>
13 
14 #include "owl-gate.h"
15 
16 void owl_gate_set(const struct owl_clk_common *common,
17 		 const struct owl_gate_hw *gate_hw, bool enable)
18 {
19 	int set = gate_hw->gate_flags & CLK_GATE_SET_TO_DISABLE ? 1 : 0;
20 	u32 reg;
21 
22 	set ^= enable;
23 
24 	regmap_read(common->regmap, gate_hw->reg, &reg);
25 
26 	if (set)
27 		reg |= BIT(gate_hw->bit_idx);
28 	else
29 		reg &= ~BIT(gate_hw->bit_idx);
30 
31 	regmap_write(common->regmap, gate_hw->reg, reg);
32 }
33 
34 static void owl_gate_disable(struct clk_hw *hw)
35 {
36 	struct owl_gate *gate = hw_to_owl_gate(hw);
37 	struct owl_clk_common *common = &gate->common;
38 
39 	owl_gate_set(common, &gate->gate_hw, false);
40 }
41 
42 static int owl_gate_enable(struct clk_hw *hw)
43 {
44 	struct owl_gate *gate = hw_to_owl_gate(hw);
45 	struct owl_clk_common *common = &gate->common;
46 
47 	owl_gate_set(common, &gate->gate_hw, true);
48 
49 	return 0;
50 }
51 
52 int owl_gate_clk_is_enabled(const struct owl_clk_common *common,
53 		   const struct owl_gate_hw *gate_hw)
54 {
55 	u32 reg;
56 
57 	regmap_read(common->regmap, gate_hw->reg, &reg);
58 
59 	if (gate_hw->gate_flags & CLK_GATE_SET_TO_DISABLE)
60 		reg ^= BIT(gate_hw->bit_idx);
61 
62 	return !!(reg & BIT(gate_hw->bit_idx));
63 }
64 
65 static int owl_gate_is_enabled(struct clk_hw *hw)
66 {
67 	struct owl_gate *gate = hw_to_owl_gate(hw);
68 	struct owl_clk_common *common = &gate->common;
69 
70 	return owl_gate_clk_is_enabled(common, &gate->gate_hw);
71 }
72 
73 const struct clk_ops owl_gate_ops = {
74 	.disable	= owl_gate_disable,
75 	.enable		= owl_gate_enable,
76 	.is_enabled	= owl_gate_is_enabled,
77 };
78