[CPUFREQ] Fix missing cpufreq_cpu_put() call in ->show
[linux-2.6.git] / drivers / cpufreq / freq_table.c
1 /*
2  * linux/drivers/cpufreq/freq_table.c
3  *
4  * Copyright (C) 2002 - 2003 Dominik Brodowski
5  */
6
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/cpufreq.h>
11
12 #define dprintk(msg...) \
13         cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, "freq-table", msg)
14
15 /*********************************************************************
16  *                     FREQUENCY TABLE HELPERS                       *
17  *********************************************************************/
18
19 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
20                                     struct cpufreq_frequency_table *table)
21 {
22         unsigned int min_freq = ~0;
23         unsigned int max_freq = 0;
24         unsigned int i;
25
26         for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
27                 unsigned int freq = table[i].frequency;
28                 if (freq == CPUFREQ_ENTRY_INVALID) {
29                         dprintk("table entry %u is invalid, skipping\n", i);
30
31                         continue;
32                 }
33                 dprintk("table entry %u: %u kHz, %u index\n",
34                                         i, freq, table[i].index);
35                 if (freq < min_freq)
36                         min_freq = freq;
37                 if (freq > max_freq)
38                         max_freq = freq;
39         }
40
41         policy->min = policy->cpuinfo.min_freq = min_freq;
42         policy->max = policy->cpuinfo.max_freq = max_freq;
43
44         if (policy->min == ~0)
45                 return -EINVAL;
46         else
47                 return 0;
48 }
49 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
50
51
52 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
53                                    struct cpufreq_frequency_table *table)
54 {
55         unsigned int next_larger = ~0;
56         unsigned int i;
57         unsigned int count = 0;
58
59         dprintk("request for verification of policy (%u - %u kHz) for cpu %u\n",
60                                         policy->min, policy->max, policy->cpu);
61
62         if (!cpu_online(policy->cpu))
63                 return -EINVAL;
64
65         cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
66                                      policy->cpuinfo.max_freq);
67
68         for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
69                 unsigned int freq = table[i].frequency;
70                 if (freq == CPUFREQ_ENTRY_INVALID)
71                         continue;
72                 if ((freq >= policy->min) && (freq <= policy->max))
73                         count++;
74                 else if ((next_larger > freq) && (freq > policy->max))
75                         next_larger = freq;
76         }
77
78         if (!count)
79                 policy->max = next_larger;
80
81         cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
82                                      policy->cpuinfo.max_freq);
83
84         dprintk("verification lead to (%u - %u kHz) for cpu %u\n",
85                                 policy->min, policy->max, policy->cpu);
86
87         return 0;
88 }
89 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
90
91
92 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
93                                    struct cpufreq_frequency_table *table,
94                                    unsigned int target_freq,
95                                    unsigned int relation,
96                                    unsigned int *index)
97 {
98         struct cpufreq_frequency_table optimal = {
99                 .index = ~0,
100                 .frequency = 0,
101         };
102         struct cpufreq_frequency_table suboptimal = {
103                 .index = ~0,
104                 .frequency = 0,
105         };
106         unsigned int i;
107
108         dprintk("request for target %u kHz (relation: %u) for cpu %u\n",
109                                         target_freq, relation, policy->cpu);
110
111         switch (relation) {
112         case CPUFREQ_RELATION_H:
113                 suboptimal.frequency = ~0;
114                 break;
115         case CPUFREQ_RELATION_L:
116                 optimal.frequency = ~0;
117                 break;
118         }
119
120         if (!cpu_online(policy->cpu))
121                 return -EINVAL;
122
123         for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
124                 unsigned int freq = table[i].frequency;
125                 if (freq == CPUFREQ_ENTRY_INVALID)
126                         continue;
127                 if ((freq < policy->min) || (freq > policy->max))
128                         continue;
129                 switch(relation) {
130                 case CPUFREQ_RELATION_H:
131                         if (freq <= target_freq) {
132                                 if (freq >= optimal.frequency) {
133                                         optimal.frequency = freq;
134                                         optimal.index = i;
135                                 }
136                         } else {
137                                 if (freq <= suboptimal.frequency) {
138                                         suboptimal.frequency = freq;
139                                         suboptimal.index = i;
140                                 }
141                         }
142                         break;
143                 case CPUFREQ_RELATION_L:
144                         if (freq >= target_freq) {
145                                 if (freq <= optimal.frequency) {
146                                         optimal.frequency = freq;
147                                         optimal.index = i;
148                                 }
149                         } else {
150                                 if (freq >= suboptimal.frequency) {
151                                         suboptimal.frequency = freq;
152                                         suboptimal.index = i;
153                                 }
154                         }
155                         break;
156                 }
157         }
158         if (optimal.index > i) {
159                 if (suboptimal.index > i)
160                         return -EINVAL;
161                 *index = suboptimal.index;
162         } else
163                 *index = optimal.index;
164
165         dprintk("target is %u (%u kHz, %u)\n", *index, table[*index].frequency,
166                 table[*index].index);
167
168         return 0;
169 }
170 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
171
172 static struct cpufreq_frequency_table *show_table[NR_CPUS];
173 /**
174  * show_available_freqs - show available frequencies for the specified CPU
175  */
176 static ssize_t show_available_freqs (struct cpufreq_policy *policy, char *buf)
177 {
178         unsigned int i = 0;
179         unsigned int cpu = policy->cpu;
180         ssize_t count = 0;
181         struct cpufreq_frequency_table *table;
182
183         if (!show_table[cpu])
184                 return -ENODEV;
185
186         table = show_table[cpu];
187
188         for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
189                 if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
190                         continue;
191                 count += sprintf(&buf[count], "%d ", table[i].frequency);
192         }
193         count += sprintf(&buf[count], "\n");
194
195         return count;
196
197 }
198
199 struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
200         .attr = { .name = "scaling_available_frequencies",
201                   .mode = 0444,
202                 },
203         .show = show_available_freqs,
204 };
205 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
206
207 /*
208  * if you use these, you must assure that the frequency table is valid
209  * all the time between get_attr and put_attr!
210  */
211 void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
212                                       unsigned int cpu)
213 {
214         dprintk("setting show_table for cpu %u to %p\n", cpu, table);
215         show_table[cpu] = table;
216 }
217 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
218
219 void cpufreq_frequency_table_put_attr(unsigned int cpu)
220 {
221         dprintk("clearing show_table for cpu %u\n", cpu);
222         show_table[cpu] = NULL;
223 }
224 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
225
226 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
227 {
228         return show_table[cpu];
229 }
230 EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
231
232 MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>");
233 MODULE_DESCRIPTION ("CPUfreq frequency table helpers");
234 MODULE_LICENSE ("GPL");