1/*
2 * Copyright 2012 Freescale Semiconductor, Inc.
3 * Copyright 2012 Linaro Ltd.
4 *
5 * The code contained herein is licensed under the GNU General Public
6 * License. You may obtain a copy of the GNU General Public License
7 * Version 2 or later at the following locations:
8 *
9 * http://www.opensource.org/licenses/gpl-license.html
10 * http://www.gnu.org/copyleft/gpl.html
11 */
12
13#include <linux/clk.h>
14#include <linux/clk-provider.h>
15#include <linux/io.h>
16#include <linux/slab.h>
17#include <linux/jiffies.h>
18#include <linux/err.h>
19#include "clk.h"
20
21static int clk_busy_wait(void __iomem *reg, u8 shift)
22{
23	unsigned long timeout = jiffies + msecs_to_jiffies(10);
24
25	while (readl_relaxed(reg) & (1 << shift))
26		if (time_after(jiffies, timeout))
27			return -ETIMEDOUT;
28
29	return 0;
30}
31
32struct clk_busy_divider {
33	struct clk_divider div;
34	const struct clk_ops *div_ops;
35	void __iomem *reg;
36	u8 shift;
37};
38
39static inline struct clk_busy_divider *to_clk_busy_divider(struct clk_hw *hw)
40{
41	struct clk_divider *div = container_of(hw, struct clk_divider, hw);
42
43	return container_of(div, struct clk_busy_divider, div);
44}
45
46static unsigned long clk_busy_divider_recalc_rate(struct clk_hw *hw,
47						  unsigned long parent_rate)
48{
49	struct clk_busy_divider *busy = to_clk_busy_divider(hw);
50
51	return busy->div_ops->recalc_rate(&busy->div.hw, parent_rate);
52}
53
54static long clk_busy_divider_round_rate(struct clk_hw *hw, unsigned long rate,
55					unsigned long *prate)
56{
57	struct clk_busy_divider *busy = to_clk_busy_divider(hw);
58
59	return busy->div_ops->round_rate(&busy->div.hw, rate, prate);
60}
61
62static int clk_busy_divider_set_rate(struct clk_hw *hw, unsigned long rate,
63		unsigned long parent_rate)
64{
65	struct clk_busy_divider *busy = to_clk_busy_divider(hw);
66	int ret;
67
68	ret = busy->div_ops->set_rate(&busy->div.hw, rate, parent_rate);
69	if (!ret)
70		ret = clk_busy_wait(busy->reg, busy->shift);
71
72	return ret;
73}
74
75static struct clk_ops clk_busy_divider_ops = {
76	.recalc_rate = clk_busy_divider_recalc_rate,
77	.round_rate = clk_busy_divider_round_rate,
78	.set_rate = clk_busy_divider_set_rate,
79};
80
81struct clk *imx_clk_busy_divider(const char *name, const char *parent_name,
82				 void __iomem *reg, u8 shift, u8 width,
83				 void __iomem *busy_reg, u8 busy_shift)
84{
85	struct clk_busy_divider *busy;
86	struct clk *clk;
87	struct clk_init_data init;
88
89	busy = kzalloc(sizeof(*busy), GFP_KERNEL);
90	if (!busy)
91		return ERR_PTR(-ENOMEM);
92
93	busy->reg = busy_reg;
94	busy->shift = busy_shift;
95
96	busy->div.reg = reg;
97	busy->div.shift = shift;
98	busy->div.width = width;
99	busy->div.lock = &imx_ccm_lock;
100	busy->div_ops = &clk_divider_ops;
101
102	init.name = name;
103	init.ops = &clk_busy_divider_ops;
104	init.flags = CLK_SET_RATE_PARENT;
105	init.parent_names = &parent_name;
106	init.num_parents = 1;
107
108	busy->div.hw.init = &init;
109
110	clk = clk_register(NULL, &busy->div.hw);
111	if (IS_ERR(clk))
112		kfree(busy);
113
114	return clk;
115}
116
117struct clk_busy_mux {
118	struct clk_mux mux;
119	const struct clk_ops *mux_ops;
120	void __iomem *reg;
121	u8 shift;
122};
123
124static inline struct clk_busy_mux *to_clk_busy_mux(struct clk_hw *hw)
125{
126	struct clk_mux *mux = container_of(hw, struct clk_mux, hw);
127
128	return container_of(mux, struct clk_busy_mux, mux);
129}
130
131static u8 clk_busy_mux_get_parent(struct clk_hw *hw)
132{
133	struct clk_busy_mux *busy = to_clk_busy_mux(hw);
134
135	return busy->mux_ops->get_parent(&busy->mux.hw);
136}
137
138static int clk_busy_mux_set_parent(struct clk_hw *hw, u8 index)
139{
140	struct clk_busy_mux *busy = to_clk_busy_mux(hw);
141	int ret;
142
143	ret = busy->mux_ops->set_parent(&busy->mux.hw, index);
144	if (!ret)
145		ret = clk_busy_wait(busy->reg, busy->shift);
146
147	return ret;
148}
149
150static struct clk_ops clk_busy_mux_ops = {
151	.get_parent = clk_busy_mux_get_parent,
152	.set_parent = clk_busy_mux_set_parent,
153};
154
155struct clk *imx_clk_busy_mux(const char *name, void __iomem *reg, u8 shift,
156			     u8 width, void __iomem *busy_reg, u8 busy_shift,
157			     const char **parent_names, int num_parents)
158{
159	struct clk_busy_mux *busy;
160	struct clk *clk;
161	struct clk_init_data init;
162
163	busy = kzalloc(sizeof(*busy), GFP_KERNEL);
164	if (!busy)
165		return ERR_PTR(-ENOMEM);
166
167	busy->reg = busy_reg;
168	busy->shift = busy_shift;
169
170	busy->mux.reg = reg;
171	busy->mux.shift = shift;
172	busy->mux.mask = BIT(width) - 1;
173	busy->mux.lock = &imx_ccm_lock;
174	busy->mux_ops = &clk_mux_ops;
175
176	init.name = name;
177	init.ops = &clk_busy_mux_ops;
178	init.flags = 0;
179	init.parent_names = parent_names;
180	init.num_parents = num_parents;
181
182	busy->mux.hw.init = &init;
183
184	clk = clk_register(NULL, &busy->mux.hw);
185	if (IS_ERR(clk))
186		kfree(busy);
187
188	return clk;
189}
190