1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * drivers/clk/at91/clk-slow.c
4 *
5 * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
6 */
7
8 #include <linux/clk-provider.h>
9 #include <linux/clkdev.h>
10 #include <linux/clk/at91_pmc.h>
11 #include <linux/of.h>
12 #include <linux/mfd/syscon.h>
13 #include <linux/regmap.h>
14
15 #include "pmc.h"
16
17 struct clk_sam9260_slow {
18 struct clk_hw hw;
19 struct regmap *regmap;
20 };
21
22 #define to_clk_sam9260_slow(hw) container_of(hw, struct clk_sam9260_slow, hw)
23
clk_sam9260_slow_get_parent(struct clk_hw * hw)24 static u8 clk_sam9260_slow_get_parent(struct clk_hw *hw)
25 {
26 struct clk_sam9260_slow *slowck = to_clk_sam9260_slow(hw);
27 unsigned int status;
28
29 regmap_read(slowck->regmap, AT91_PMC_SR, &status);
30
31 return status & AT91_PMC_OSCSEL ? 1 : 0;
32 }
33
34 static const struct clk_ops sam9260_slow_ops = {
35 .get_parent = clk_sam9260_slow_get_parent,
36 };
37
38 struct clk_hw * __init
at91_clk_register_sam9260_slow(struct regmap * regmap,const char * name,const char ** parent_names,int num_parents)39 at91_clk_register_sam9260_slow(struct regmap *regmap,
40 const char *name,
41 const char **parent_names,
42 int num_parents)
43 {
44 struct clk_sam9260_slow *slowck;
45 struct clk_hw *hw;
46 struct clk_init_data init;
47 int ret;
48
49 if (!name)
50 return ERR_PTR(-EINVAL);
51
52 if (!parent_names || !num_parents)
53 return ERR_PTR(-EINVAL);
54
55 slowck = kzalloc(sizeof(*slowck), GFP_KERNEL);
56 if (!slowck)
57 return ERR_PTR(-ENOMEM);
58
59 init.name = name;
60 init.ops = &sam9260_slow_ops;
61 init.parent_names = parent_names;
62 init.num_parents = num_parents;
63 init.flags = 0;
64
65 slowck->hw.init = &init;
66 slowck->regmap = regmap;
67
68 hw = &slowck->hw;
69 ret = clk_hw_register(NULL, &slowck->hw);
70 if (ret) {
71 kfree(slowck);
72 hw = ERR_PTR(ret);
73 }
74
75 return hw;
76 }
77