1 /*
2  *
3  * This software is licensed under the terms of the GNU General Public
4  * License version 2, as published by the Free Software Foundation, and
5  * may be copied, distributed, and modified under those terms.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  */
12 
13 #include <linux/slab.h>
14 #include <linux/bitops.h>
15 #include <linux/regmap.h>
16 #include <linux/clk.h>
17 #include <linux/clk-provider.h>
18 #include "clk.h"
19 
20 struct rockchip_muxgrf_clock {
21 	struct clk_hw		hw;
22 	struct regmap		*regmap;
23 	u32			reg;
24 	u32			shift;
25 	u32			width;
26 	int			flags;
27 };
28 
29 #define to_muxgrf_clock(_hw) container_of(_hw, struct rockchip_muxgrf_clock, hw)
30 
31 static u8 rockchip_muxgrf_get_parent(struct clk_hw *hw)
32 {
33 	struct rockchip_muxgrf_clock *mux = to_muxgrf_clock(hw);
34 	unsigned int mask = GENMASK(mux->width - 1, 0);
35 	unsigned int val;
36 
37 	regmap_read(mux->regmap, mux->reg, &val);
38 
39 	val >>= mux->shift;
40 	val &= mask;
41 
42 	return val;
43 }
44 
45 static int rockchip_muxgrf_set_parent(struct clk_hw *hw, u8 index)
46 {
47 	struct rockchip_muxgrf_clock *mux = to_muxgrf_clock(hw);
48 	unsigned int mask = GENMASK(mux->width + mux->shift - 1, mux->shift);
49 	unsigned int val;
50 
51 	val = index;
52 	val <<= mux->shift;
53 
54 	if (mux->flags & CLK_MUX_HIWORD_MASK)
55 		return regmap_write(mux->regmap, mux->reg, val | (mask << 16));
56 	else
57 		return regmap_update_bits(mux->regmap, mux->reg, mask, val);
58 }
59 
60 static const struct clk_ops rockchip_muxgrf_clk_ops = {
61 	.get_parent = rockchip_muxgrf_get_parent,
62 	.set_parent = rockchip_muxgrf_set_parent,
63 	.determine_rate = __clk_mux_determine_rate,
64 };
65 
66 struct clk *rockchip_clk_register_muxgrf(const char *name,
67 				const char *const *parent_names, u8 num_parents,
68 				int flags, struct regmap *regmap, int reg,
69 				int shift, int width, int mux_flags)
70 {
71 	struct rockchip_muxgrf_clock *muxgrf_clock;
72 	struct clk_init_data init;
73 	struct clk *clk;
74 
75 	if (IS_ERR(regmap)) {
76 		pr_err("%s: regmap not available\n", __func__);
77 		return ERR_PTR(-ENOTSUPP);
78 	}
79 
80 	muxgrf_clock = kmalloc(sizeof(*muxgrf_clock), GFP_KERNEL);
81 	if (!muxgrf_clock)
82 		return ERR_PTR(-ENOMEM);
83 
84 	init.name = name;
85 	init.flags = flags;
86 	init.num_parents = num_parents;
87 	init.parent_names = parent_names;
88 	init.ops = &rockchip_muxgrf_clk_ops;
89 
90 	muxgrf_clock->hw.init = &init;
91 	muxgrf_clock->regmap = regmap;
92 	muxgrf_clock->reg = reg;
93 	muxgrf_clock->shift = shift;
94 	muxgrf_clock->width = width;
95 	muxgrf_clock->flags = mux_flags;
96 
97 	clk = clk_register(NULL, &muxgrf_clock->hw);
98 	if (IS_ERR(clk))
99 		kfree(muxgrf_clock);
100 
101 	return clk;
102 }
103