1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 */
4
5 #define pr_fmt(fmt) "imx:clk-gpr-mux: " fmt
6
7 #include <linux/module.h>
8
9 #include <linux/clk-provider.h>
10 #include <linux/errno.h>
11 #include <linux/export.h>
12 #include <linux/io.h>
13 #include <linux/slab.h>
14 #include <linux/regmap.h>
15 #include <linux/mfd/syscon.h>
16
17 #include "clk.h"
18
19 struct imx_clk_gpr {
20 struct clk_hw hw;
21 struct regmap *regmap;
22 u32 mask;
23 u32 reg;
24 const u32 *mux_table;
25 };
26
to_imx_clk_gpr(struct clk_hw * hw)27 static struct imx_clk_gpr *to_imx_clk_gpr(struct clk_hw *hw)
28 {
29 return container_of(hw, struct imx_clk_gpr, hw);
30 }
31
imx_clk_gpr_mux_get_parent(struct clk_hw * hw)32 static u8 imx_clk_gpr_mux_get_parent(struct clk_hw *hw)
33 {
34 struct imx_clk_gpr *priv = to_imx_clk_gpr(hw);
35 unsigned int val;
36 int ret;
37
38 ret = regmap_read(priv->regmap, priv->reg, &val);
39 if (ret)
40 goto get_parent_err;
41
42 val &= priv->mask;
43
44 ret = clk_mux_val_to_index(hw, priv->mux_table, 0, val);
45 if (ret < 0)
46 goto get_parent_err;
47
48 return ret;
49
50 get_parent_err:
51 pr_err("%s: failed to get parent (%pe)\n",
52 clk_hw_get_name(hw), ERR_PTR(ret));
53
54 /* return some realistic non negative value. Potentially we could
55 * give index to some dummy error parent.
56 */
57 return 0;
58 }
59
imx_clk_gpr_mux_set_parent(struct clk_hw * hw,u8 index)60 static int imx_clk_gpr_mux_set_parent(struct clk_hw *hw, u8 index)
61 {
62 struct imx_clk_gpr *priv = to_imx_clk_gpr(hw);
63 unsigned int val = clk_mux_index_to_val(priv->mux_table, 0, index);
64
65 return regmap_update_bits(priv->regmap, priv->reg, priv->mask, val);
66 }
67
68 static const struct clk_ops imx_clk_gpr_mux_ops = {
69 .get_parent = imx_clk_gpr_mux_get_parent,
70 .set_parent = imx_clk_gpr_mux_set_parent,
71 .determine_rate = __clk_mux_determine_rate,
72 };
73
imx_clk_gpr_mux(const char * name,const char * compatible,u32 reg,const char ** parent_names,u8 num_parents,const u32 * mux_table,u32 mask)74 struct clk_hw *imx_clk_gpr_mux(const char *name, const char *compatible,
75 u32 reg, const char **parent_names,
76 u8 num_parents, const u32 *mux_table, u32 mask)
77 {
78 struct clk_init_data init = { };
79 struct imx_clk_gpr *priv;
80 struct regmap *regmap;
81 struct clk_hw *hw;
82 int ret;
83
84 regmap = syscon_regmap_lookup_by_compatible(compatible);
85 if (IS_ERR(regmap)) {
86 pr_err("failed to find %s regmap\n", compatible);
87 return ERR_CAST(regmap);
88 }
89
90 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
91 if (!priv)
92 return ERR_PTR(-ENOMEM);
93
94 init.name = name;
95 init.ops = &imx_clk_gpr_mux_ops;
96 init.parent_names = parent_names;
97 init.num_parents = num_parents;
98 init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
99
100 priv->hw.init = &init;
101 priv->regmap = regmap;
102 priv->mux_table = mux_table;
103 priv->reg = reg;
104 priv->mask = mask;
105
106 hw = &priv->hw;
107 ret = clk_hw_register(NULL, &priv->hw);
108 if (ret) {
109 kfree(priv);
110 hw = ERR_PTR(ret);
111 }
112
113 return hw;
114 }
115