/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
#include <linux/module.h>
#include <linux/spinlock.h>
#include "gpiomux.h"
static DEFINE_SPINLOCK(gpiomux_lock);
int msm_gpiomux_write(unsigned gpio,
gpiomux_config_t active,
gpiomux_config_t suspended)
{
struct msm_gpiomux_config *cfg = msm_gpiomux_configs + gpio;
unsigned long irq_flags;
gpiomux_config_t setting;
if (gpio >= GPIOMUX_NGPIOS)
return -EINVAL;
spin_lock_irqsave(&gpiomux_lock, irq_flags);
if (active & GPIOMUX_VALID)
cfg->active = active;
if (suspended & GPIOMUX_VALID)
cfg->suspended = suspended;
setting = cfg->ref ? active : suspended;
if (setting & GPIOMUX_VALID)
__msm_gpiomux_write(gpio, setting);
spin_unlock_irqrestore(&gpiomux_lock, irq_flags);
return 0;
}
EXPORT_SYMBOL(msm_gpiomux_write);
int msm_gpiomux_get(unsigned gpio)
{
struct msm_gpiomux_config *cfg = msm_gpiomux_configs + gpio;
unsigned long irq_flags;
if (gpio >= GPIOMUX_NGPIOS)
return -EINVAL;
spin_lock_irqsave(&gpiomux_lock, irq_flags);
if (cfg->ref++ == 0 && cfg->active & GPIOMUX_VALID)
__msm_gpiomux_write(gpio, cfg->active);
spin_unlock_irqrestore(&gpiomux_lock, irq_flags);
return 0;
}
EXPORT_SYMBOL(msm_gpiomux_get);
int msm_gpiomux_put(unsigned gpio)
{
struct msm_gpiomux_config *cfg = msm_gpiomux_configs + gpio;
unsigned long irq_flags;
if (gpio >= GPIOMUX_NGPIOS)
return -EINVAL;
spin_lock_irqsave(&gpiomux_lock, irq_flags);
BUG_ON(cfg->ref == 0);
if (--cfg->ref == 0 && cfg->suspended & GPIOMUX_VALID)
__msm_gpiomux_write(gpio, cfg->suspended);
spin_unlock_irqrestore(&gpiomux_lock, irq_flags);
return 0;
}
EXPORT_SYMBOL(msm_gpiomux_put);
static int __init gpiomux_init(void)
{
unsigned n;
for (n = 0; n < GPIOMUX_NGPIOS; ++n) {
msm_gpiomux_configs[n].ref = 0;
if (!(msm_gpiomux_configs[n].suspended & GPIOMUX_VALID))
continue;
__msm_gpiomux_write(n, msm_gpiomux_configs[n].suspended);
}
return 0;
}
postcore_initcall(gpiomux_init);
