1 /*
2 * Copyright (C) 2013 Freescale Semiconductor, Inc.
3 *
4 * The code contained herein is licensed under the GNU General Public
5 * License. You may obtain a copy of the GNU General Public License
6 * Version 2 or later at the following locations:
7 *
8 * http://www.opensource.org/licenses/gpl-license.html
9 * http://www.gnu.org/copyleft/gpl.html
10 */
11
12 #include <linux/clk-provider.h>
13 #include <linux/err.h>
14 #include <linux/io.h>
15 #include <linux/slab.h>
16 #include "clk.h"
17
18 /**
19 * struct clk_fixup_mux - imx integer fixup multiplexer clock
20 * @mux: the parent class
21 * @ops: pointer to clk_ops of parent class
22 * @fixup: a hook to fixup the write value
23 *
24 * The imx fixup multiplexer clock is a subclass of basic clk_mux
25 * with an addtional fixup hook.
26 */
27 struct clk_fixup_mux {
28 struct clk_mux mux;
29 const struct clk_ops *ops;
30 void (*fixup)(u32 *val);
31 };
32
to_clk_fixup_mux(struct clk_hw * hw)33 static inline struct clk_fixup_mux *to_clk_fixup_mux(struct clk_hw *hw)
34 {
35 struct clk_mux *mux = to_clk_mux(hw);
36
37 return container_of(mux, struct clk_fixup_mux, mux);
38 }
39
clk_fixup_mux_get_parent(struct clk_hw * hw)40 static u8 clk_fixup_mux_get_parent(struct clk_hw *hw)
41 {
42 struct clk_fixup_mux *fixup_mux = to_clk_fixup_mux(hw);
43
44 return fixup_mux->ops->get_parent(&fixup_mux->mux.hw);
45 }
46
clk_fixup_mux_set_parent(struct clk_hw * hw,u8 index)47 static int clk_fixup_mux_set_parent(struct clk_hw *hw, u8 index)
48 {
49 struct clk_fixup_mux *fixup_mux = to_clk_fixup_mux(hw);
50 struct clk_mux *mux = to_clk_mux(hw);
51 unsigned long flags = 0;
52 u32 val;
53
54 spin_lock_irqsave(mux->lock, flags);
55
56 val = readl(mux->reg);
57 val &= ~(mux->mask << mux->shift);
58 val |= index << mux->shift;
59 fixup_mux->fixup(&val);
60 writel(val, mux->reg);
61
62 spin_unlock_irqrestore(mux->lock, flags);
63
64 return 0;
65 }
66
67 static const struct clk_ops clk_fixup_mux_ops = {
68 .get_parent = clk_fixup_mux_get_parent,
69 .set_parent = clk_fixup_mux_set_parent,
70 };
71
imx_clk_fixup_mux(const char * name,void __iomem * reg,u8 shift,u8 width,const char * const * parents,int num_parents,void (* fixup)(u32 * val))72 struct clk *imx_clk_fixup_mux(const char *name, void __iomem *reg,
73 u8 shift, u8 width, const char * const *parents,
74 int num_parents, void (*fixup)(u32 *val))
75 {
76 struct clk_fixup_mux *fixup_mux;
77 struct clk *clk;
78 struct clk_init_data init;
79
80 if (!fixup)
81 return ERR_PTR(-EINVAL);
82
83 fixup_mux = kzalloc(sizeof(*fixup_mux), GFP_KERNEL);
84 if (!fixup_mux)
85 return ERR_PTR(-ENOMEM);
86
87 init.name = name;
88 init.ops = &clk_fixup_mux_ops;
89 init.parent_names = parents;
90 init.num_parents = num_parents;
91 init.flags = 0;
92
93 fixup_mux->mux.reg = reg;
94 fixup_mux->mux.shift = shift;
95 fixup_mux->mux.mask = BIT(width) - 1;
96 fixup_mux->mux.lock = &imx_ccm_lock;
97 fixup_mux->mux.hw.init = &init;
98 fixup_mux->ops = &clk_mux_ops;
99 fixup_mux->fixup = fixup;
100
101 clk = clk_register(NULL, &fixup_mux->mux.hw);
102 if (IS_ERR(clk))
103 kfree(fixup_mux);
104
105 return clk;
106 }
107