1// SPDX-License-Identifier: GPL-2.0
 2//
 3// Spreadtrum multiplexer clock driver
 4//
 5// Copyright (C) 2017 Spreadtrum, Inc.
 6// Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
 7
 8#include <linux/clk.h>
 9#include <linux/clk-provider.h>
10#include <linux/regmap.h>
11
12#include "mux.h"
13
14u8 sprd_mux_helper_get_parent(const struct sprd_clk_common *common,
15			      const struct sprd_mux_ssel *mux)
16{
17	unsigned int reg;
18	u8 parent;
19	int num_parents;
20	int i;
21
22	regmap_read(common->regmap, common->reg, &reg);
23	parent = reg >> mux->shift;
24	parent &= (1 << mux->width) - 1;
25
26	if (!mux->table)
27		return parent;
28
29	num_parents = clk_hw_get_num_parents(&common->hw);
30
31	for (i = 0; i < num_parents - 1; i++)
32		if (parent >= mux->table[i] && parent < mux->table[i + 1])
33			return i;
34
35	return num_parents - 1;
36}
37EXPORT_SYMBOL_GPL(sprd_mux_helper_get_parent);
38
39static u8 sprd_mux_get_parent(struct clk_hw *hw)
40{
41	struct sprd_mux *cm = hw_to_sprd_mux(hw);
42
43	return sprd_mux_helper_get_parent(&cm->common, &cm->mux);
44}
45
46int sprd_mux_helper_set_parent(const struct sprd_clk_common *common,
47			       const struct sprd_mux_ssel *mux,
48			       u8 index)
49{
50	unsigned int reg;
51
52	if (mux->table)
53		index = mux->table[index];
54
55	regmap_read(common->regmap, common->reg, &reg);
56	reg &= ~GENMASK(mux->width + mux->shift - 1, mux->shift);
57	regmap_write(common->regmap, common->reg,
58			  reg | (index << mux->shift));
59
60	return 0;
61}
62EXPORT_SYMBOL_GPL(sprd_mux_helper_set_parent);
63
64static int sprd_mux_set_parent(struct clk_hw *hw, u8 index)
65{
66	struct sprd_mux *cm = hw_to_sprd_mux(hw);
67
68	return sprd_mux_helper_set_parent(&cm->common, &cm->mux, index);
69}
70
71const struct clk_ops sprd_mux_ops = {
72	.get_parent = sprd_mux_get_parent,
73	.set_parent = sprd_mux_set_parent,
74	.determine_rate = __clk_mux_determine_rate,
75};
76EXPORT_SYMBOL_GPL(sprd_mux_ops);