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Brian Swetland600f7cf2008-09-09 11:04:14 -07001/* arch/arm/mach-msm/clock.c
2 *
3 * Copyright (C) 2007 Google, Inc.
4 * Copyright (c) 2007 QUALCOMM Incorporated
5 *
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 */
16
17#include <linux/version.h>
18#include <linux/kernel.h>
19#include <linux/init.h>
20#include <linux/module.h>
21#include <linux/list.h>
22#include <linux/err.h>
23#include <linux/clk.h>
24#include <linux/spinlock.h>
25
26#include "clock.h"
27#include "proc_comm.h"
28
29static DEFINE_MUTEX(clocks_mutex);
30static DEFINE_SPINLOCK(clocks_lock);
31static LIST_HEAD(clocks);
32
33/*
34 * glue for the proc_comm interface
35 */
36static inline int pc_clk_enable(unsigned id)
37{
38 return msm_proc_comm(PCOM_CLKCTL_RPC_ENABLE, &id, NULL);
39}
40
41static inline void pc_clk_disable(unsigned id)
42{
43 msm_proc_comm(PCOM_CLKCTL_RPC_DISABLE, &id, NULL);
44}
45
46static inline int pc_clk_set_rate(unsigned id, unsigned rate)
47{
48 return msm_proc_comm(PCOM_CLKCTL_RPC_SET_RATE, &id, &rate);
49}
50
51static inline int pc_clk_set_min_rate(unsigned id, unsigned rate)
52{
53 return msm_proc_comm(PCOM_CLKCTL_RPC_MIN_RATE, &id, &rate);
54}
55
56static inline int pc_clk_set_max_rate(unsigned id, unsigned rate)
57{
58 return msm_proc_comm(PCOM_CLKCTL_RPC_MAX_RATE, &id, &rate);
59}
60
61static inline int pc_clk_set_flags(unsigned id, unsigned flags)
62{
63 return msm_proc_comm(PCOM_CLKCTL_RPC_SET_FLAGS, &id, &flags);
64}
65
66static inline unsigned pc_clk_get_rate(unsigned id)
67{
68 if (msm_proc_comm(PCOM_CLKCTL_RPC_RATE, &id, NULL))
69 return 0;
70 else
71 return id;
72}
73
74static inline unsigned pc_clk_is_enabled(unsigned id)
75{
76 if (msm_proc_comm(PCOM_CLKCTL_RPC_ENABLED, &id, NULL))
77 return 0;
78 else
79 return id;
80}
81
82static inline int pc_pll_request(unsigned id, unsigned on)
83{
84 on = !!on;
85 return msm_proc_comm(PCOM_CLKCTL_RPC_PLL_REQUEST, &id, &on);
86}
87
88/*
89 * Standard clock functions defined in include/linux/clk.h
90 */
91struct clk *clk_get(struct device *dev, const char *id)
92{
93 struct clk *clk;
94
95 mutex_lock(&clocks_mutex);
96
97 list_for_each_entry(clk, &clocks, list)
98 if (!strcmp(id, clk->name) && clk->dev == dev)
99 goto found_it;
100
101 list_for_each_entry(clk, &clocks, list)
102 if (!strcmp(id, clk->name) && clk->dev == NULL)
103 goto found_it;
104
105 clk = ERR_PTR(-ENOENT);
106found_it:
107 mutex_unlock(&clocks_mutex);
108 return clk;
109}
110EXPORT_SYMBOL(clk_get);
111
112void clk_put(struct clk *clk)
113{
114}
115EXPORT_SYMBOL(clk_put);
116
117int clk_enable(struct clk *clk)
118{
119 unsigned long flags;
120 spin_lock_irqsave(&clocks_lock, flags);
121 clk->count++;
122 if (clk->count == 1)
123 pc_clk_enable(clk->id);
124 spin_unlock_irqrestore(&clocks_lock, flags);
125 return 0;
126}
127EXPORT_SYMBOL(clk_enable);
128
129void clk_disable(struct clk *clk)
130{
131 unsigned long flags;
132 spin_lock_irqsave(&clocks_lock, flags);
133 BUG_ON(clk->count == 0);
134 clk->count--;
135 if (clk->count == 0)
136 pc_clk_disable(clk->id);
137 spin_unlock_irqrestore(&clocks_lock, flags);
138}
139EXPORT_SYMBOL(clk_disable);
140
141unsigned long clk_get_rate(struct clk *clk)
142{
143 return pc_clk_get_rate(clk->id);
144}
145EXPORT_SYMBOL(clk_get_rate);
146
147int clk_set_rate(struct clk *clk, unsigned long rate)
148{
149 int ret;
150 if (clk->flags & CLKFLAG_USE_MIN_MAX_TO_SET) {
151 ret = pc_clk_set_max_rate(clk->id, rate);
152 if (ret)
153 return ret;
154 return pc_clk_set_min_rate(clk->id, rate);
155 }
156 return pc_clk_set_rate(clk->id, rate);
157}
158EXPORT_SYMBOL(clk_set_rate);
159
160int clk_set_parent(struct clk *clk, struct clk *parent)
161{
162 return -ENOSYS;
163}
164EXPORT_SYMBOL(clk_set_parent);
165
166struct clk *clk_get_parent(struct clk *clk)
167{
168 return ERR_PTR(-ENOSYS);
169}
170EXPORT_SYMBOL(clk_get_parent);
171
172int clk_set_flags(struct clk *clk, unsigned long flags)
173{
174 if (clk == NULL || IS_ERR(clk))
175 return -EINVAL;
176 return pc_clk_set_flags(clk->id, flags);
177}
178EXPORT_SYMBOL(clk_set_flags);
179
180
181void __init msm_clock_init(void)
182{
183 unsigned n;
184
185 spin_lock_init(&clocks_lock);
186 mutex_lock(&clocks_mutex);
187 for (n = 0; n < msm_num_clocks; n++)
188 list_add_tail(&msm_clocks[n].list, &clocks);
189 mutex_unlock(&clocks_mutex);
190}
191
192/* The bootloader and/or AMSS may have left various clocks enabled.
193 * Disable any clocks that belong to us (CLKFLAG_AUTO_OFF) but have
194 * not been explicitly enabled by a clk_enable() call.
195 */
196static int __init clock_late_init(void)
197{
198 unsigned long flags;
199 struct clk *clk;
200 unsigned count = 0;
201
202 mutex_lock(&clocks_mutex);
203 list_for_each_entry(clk, &clocks, list) {
204 if (clk->flags & CLKFLAG_AUTO_OFF) {
205 spin_lock_irqsave(&clocks_lock, flags);
206 if (!clk->count) {
207 count++;
208 pc_clk_disable(clk->id);
209 }
210 spin_unlock_irqrestore(&clocks_lock, flags);
211 }
212 }
213 mutex_unlock(&clocks_mutex);
214 pr_info("clock_late_init() disabled %d unused clocks\n", count);
215 return 0;
216}
217
218late_initcall(clock_late_init);