1 /* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
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.
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.
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
17 #include <linux/module.h>
18 #include <linux/spinlock.h>
21 static DEFINE_SPINLOCK(gpiomux_lock);
23 int msm_gpiomux_write(unsigned gpio,
24 gpiomux_config_t active,
25 gpiomux_config_t suspended)
27 struct msm_gpiomux_config *cfg = msm_gpiomux_configs + gpio;
28 unsigned long irq_flags;
29 gpiomux_config_t setting;
31 if (gpio >= GPIOMUX_NGPIOS)
34 spin_lock_irqsave(&gpiomux_lock, irq_flags);
36 if (active & GPIOMUX_VALID)
39 if (suspended & GPIOMUX_VALID)
40 cfg->suspended = suspended;
42 setting = cfg->ref ? active : suspended;
43 if (setting & GPIOMUX_VALID)
44 __msm_gpiomux_write(gpio, setting);
46 spin_unlock_irqrestore(&gpiomux_lock, irq_flags);
49 EXPORT_SYMBOL(msm_gpiomux_write);
51 int msm_gpiomux_get(unsigned gpio)
53 struct msm_gpiomux_config *cfg = msm_gpiomux_configs + gpio;
54 unsigned long irq_flags;
56 if (gpio >= GPIOMUX_NGPIOS)
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);
65 EXPORT_SYMBOL(msm_gpiomux_get);
67 int msm_gpiomux_put(unsigned gpio)
69 struct msm_gpiomux_config *cfg = msm_gpiomux_configs + gpio;
70 unsigned long irq_flags;
72 if (gpio >= GPIOMUX_NGPIOS)
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);
82 EXPORT_SYMBOL(msm_gpiomux_put);
84 static int __init gpiomux_init(void)
88 for (n = 0; n < GPIOMUX_NGPIOS; ++n) {
89 msm_gpiomux_configs[n].ref = 0;
90 if (!(msm_gpiomux_configs[n].suspended & GPIOMUX_VALID))
92 __msm_gpiomux_write(n, msm_gpiomux_configs[n].suspended);
96 postcore_initcall(gpiomux_init);