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
19struct 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
27static 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
32static 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
50get_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
60static 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
68static 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
74struct 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