xref: /openbmc/linux/drivers/clk/at91/clk-i2s-mux.c (revision e15a5365)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Copyright (C) 2018 Microchip Technology Inc,
4  *                     Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
5  *
6  *
7  */
8 
9 #include <linux/clk-provider.h>
10 #include <linux/of.h>
11 #include <linux/mfd/syscon.h>
12 #include <linux/regmap.h>
13 #include <linux/slab.h>
14 
15 #include <soc/at91/atmel-sfr.h>
16 
17 #include "pmc.h"
18 
19 struct clk_i2s_mux {
20 	struct clk_hw hw;
21 	struct regmap *regmap;
22 	u8 bus_id;
23 };
24 
25 #define to_clk_i2s_mux(hw) container_of(hw, struct clk_i2s_mux, hw)
26 
27 static u8 clk_i2s_mux_get_parent(struct clk_hw *hw)
28 {
29 	struct clk_i2s_mux *mux = to_clk_i2s_mux(hw);
30 	u32 val;
31 
32 	regmap_read(mux->regmap, AT91_SFR_I2SCLKSEL, &val);
33 
34 	return (val & BIT(mux->bus_id)) >> mux->bus_id;
35 }
36 
37 static int clk_i2s_mux_set_parent(struct clk_hw *hw, u8 index)
38 {
39 	struct clk_i2s_mux *mux = to_clk_i2s_mux(hw);
40 
41 	return regmap_update_bits(mux->regmap, AT91_SFR_I2SCLKSEL,
42 				  BIT(mux->bus_id), index << mux->bus_id);
43 }
44 
45 static const struct clk_ops clk_i2s_mux_ops = {
46 	.get_parent = clk_i2s_mux_get_parent,
47 	.set_parent = clk_i2s_mux_set_parent,
48 	.determine_rate = __clk_mux_determine_rate,
49 };
50 
51 struct clk_hw * __init
52 at91_clk_i2s_mux_register(struct regmap *regmap, const char *name,
53 			  const char * const *parent_names,
54 			  unsigned int num_parents, u8 bus_id)
55 {
56 	struct clk_init_data init = {};
57 	struct clk_i2s_mux *i2s_ck;
58 	int ret;
59 
60 	i2s_ck = kzalloc(sizeof(*i2s_ck), GFP_KERNEL);
61 	if (!i2s_ck)
62 		return ERR_PTR(-ENOMEM);
63 
64 	init.name = name;
65 	init.ops = &clk_i2s_mux_ops;
66 	init.parent_names = parent_names;
67 	init.num_parents = num_parents;
68 
69 	i2s_ck->hw.init = &init;
70 	i2s_ck->bus_id = bus_id;
71 	i2s_ck->regmap = regmap;
72 
73 	ret = clk_hw_register(NULL, &i2s_ck->hw);
74 	if (ret) {
75 		kfree(i2s_ck);
76 		return ERR_PTR(ret);
77 	}
78 
79 	return &i2s_ck->hw;
80 }
81