1 /* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
2 *
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License version 2 and
5 * only version 2 as published by the Free Software Foundation.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
15 * 02110-1301, USA.
16 */
17 #include <linux/module.h>
18 #include <linux/spinlock.h>
19 #include "gpiomux.h"
20
21 static DEFINE_SPINLOCK(gpiomux_lock);
22
msm_gpiomux_write(unsigned gpio,gpiomux_config_t active,gpiomux_config_t suspended)23 int msm_gpiomux_write(unsigned gpio,
24 gpiomux_config_t active,
25 gpiomux_config_t suspended)
26 {
27 struct msm_gpiomux_config *cfg = msm_gpiomux_configs + gpio;
28 unsigned long irq_flags;
29 gpiomux_config_t setting;
30
31 if (gpio >= GPIOMUX_NGPIOS)
32 return -EINVAL;
33
34 spin_lock_irqsave(&gpiomux_lock, irq_flags);
35
36 if (active & GPIOMUX_VALID)
37 cfg->active = active;
38
39 if (suspended & GPIOMUX_VALID)
40 cfg->suspended = suspended;
41
42 setting = cfg->ref ? active : suspended;
43 if (setting & GPIOMUX_VALID)
44 __msm_gpiomux_write(gpio, setting);
45
46 spin_unlock_irqrestore(&gpiomux_lock, irq_flags);
47 return 0;
48 }
49 EXPORT_SYMBOL(msm_gpiomux_write);
50
msm_gpiomux_get(unsigned gpio)51 int msm_gpiomux_get(unsigned gpio)
52 {
53 struct msm_gpiomux_config *cfg = msm_gpiomux_configs + gpio;
54 unsigned long irq_flags;
55
56 if (gpio >= GPIOMUX_NGPIOS)
57 return -EINVAL;
58
59 spin_lock_irqsave(&gpiomux_lock, irq_flags);
60 if (cfg->ref++ == 0 && cfg->active & GPIOMUX_VALID)
61 __msm_gpiomux_write(gpio, cfg->active);
62 spin_unlock_irqrestore(&gpiomux_lock, irq_flags);
63 return 0;
64 }
65 EXPORT_SYMBOL(msm_gpiomux_get);
66
msm_gpiomux_put(unsigned gpio)67 int msm_gpiomux_put(unsigned gpio)
68 {
69 struct msm_gpiomux_config *cfg = msm_gpiomux_configs + gpio;
70 unsigned long irq_flags;
71
72 if (gpio >= GPIOMUX_NGPIOS)
73 return -EINVAL;
74
75 spin_lock_irqsave(&gpiomux_lock, irq_flags);
76 BUG_ON(cfg->ref == 0);
77 if (--cfg->ref == 0 && cfg->suspended & GPIOMUX_VALID)
78 __msm_gpiomux_write(gpio, cfg->suspended);
79 spin_unlock_irqrestore(&gpiomux_lock, irq_flags);
80 return 0;
81 }
82 EXPORT_SYMBOL(msm_gpiomux_put);
83
gpiomux_init(void)84 static int __init gpiomux_init(void)
85 {
86 unsigned n;
87
88 for (n = 0; n < GPIOMUX_NGPIOS; ++n) {
89 msm_gpiomux_configs[n].ref = 0;
90 if (!(msm_gpiomux_configs[n].suspended & GPIOMUX_VALID))
91 continue;
92 __msm_gpiomux_write(n, msm_gpiomux_configs[n].suspended);
93 }
94 return 0;
95 }
96 postcore_initcall(gpiomux_init);
97