linux-hardened/arch/arm/plat-omap/dmtimer.c
Timo Kokkonen c5491d1ae1 ARM: OMAP: dmtimers: Fix locking issue in omap_dm_timer_request*()
Calling omap_dm_timer_prepare while the spinlock is held is not
allowed as sleeping functions are called later on during the
preparation (namely within clk_get()).

dm_timer_lock is only required for protecting the
omap_timer_list. After the timer is marked as reserved, the lock is no
longer needed and should be freed.

Signed-off-by: Timo Kokkonen <timo.t.kokkonen@iki.fi>
Cc: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-08-13 06:23:16 -07:00

806 lines
20 KiB
C

/*
* linux/arch/arm/plat-omap/dmtimer.c
*
* OMAP Dual-Mode Timers
*
* Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
* Tarun Kanti DebBarma <tarun.kanti@ti.com>
* Thara Gopinath <thara@ti.com>
*
* dmtimer adaptation to platform_driver.
*
* Copyright (C) 2005 Nokia Corporation
* OMAP2 support by Juha Yrjola
* API improvements and OMAP2 clock framework support by Timo Teras
*
* Copyright (C) 2009 Texas Instruments
* Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* 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.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/io.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/pm_runtime.h>
#include <plat/dmtimer.h>
#include <plat/omap-pm.h>
#include <mach/hardware.h>
static u32 omap_reserved_systimers;
static LIST_HEAD(omap_timer_list);
static DEFINE_SPINLOCK(dm_timer_lock);
/**
* omap_dm_timer_read_reg - read timer registers in posted and non-posted mode
* @timer: timer pointer over which read operation to perform
* @reg: lowest byte holds the register offset
*
* The posted mode bit is encoded in reg. Note that in posted mode write
* pending bit must be checked. Otherwise a read of a non completed write
* will produce an error.
*/
static inline u32 omap_dm_timer_read_reg(struct omap_dm_timer *timer, u32 reg)
{
WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
return __omap_dm_timer_read(timer, reg, timer->posted);
}
/**
* omap_dm_timer_write_reg - write timer registers in posted and non-posted mode
* @timer: timer pointer over which write operation is to perform
* @reg: lowest byte holds the register offset
* @value: data to write into the register
*
* The posted mode bit is encoded in reg. Note that in posted mode the write
* pending bit must be checked. Otherwise a write on a register which has a
* pending write will be lost.
*/
static void omap_dm_timer_write_reg(struct omap_dm_timer *timer, u32 reg,
u32 value)
{
WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
__omap_dm_timer_write(timer, reg, value, timer->posted);
}
static void omap_timer_restore_context(struct omap_dm_timer *timer)
{
if (timer->revision == 1)
__raw_writel(timer->context.tistat, timer->sys_stat);
__raw_writel(timer->context.tisr, timer->irq_stat);
omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG,
timer->context.twer);
omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG,
timer->context.tcrr);
omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG,
timer->context.tldr);
omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG,
timer->context.tmar);
omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG,
timer->context.tsicr);
__raw_writel(timer->context.tier, timer->irq_ena);
omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG,
timer->context.tclr);
}
static void omap_dm_timer_wait_for_reset(struct omap_dm_timer *timer)
{
int c;
if (!timer->sys_stat)
return;
c = 0;
while (!(__raw_readl(timer->sys_stat) & 1)) {
c++;
if (c > 100000) {
printk(KERN_ERR "Timer failed to reset\n");
return;
}
}
}
static void omap_dm_timer_reset(struct omap_dm_timer *timer)
{
omap_dm_timer_enable(timer);
if (timer->pdev->id != 1) {
omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
omap_dm_timer_wait_for_reset(timer);
}
__omap_dm_timer_reset(timer, 0, 0);
omap_dm_timer_disable(timer);
timer->posted = 1;
}
int omap_dm_timer_prepare(struct omap_dm_timer *timer)
{
int ret;
/*
* FIXME: OMAP1 devices do not use the clock framework for dmtimers so
* do not call clk_get() for these devices.
*/
if (!(timer->capability & OMAP_TIMER_NEEDS_RESET)) {
timer->fclk = clk_get(&timer->pdev->dev, "fck");
if (WARN_ON_ONCE(IS_ERR_OR_NULL(timer->fclk))) {
timer->fclk = NULL;
dev_err(&timer->pdev->dev, ": No fclk handle.\n");
return -EINVAL;
}
}
if (timer->capability & OMAP_TIMER_NEEDS_RESET)
omap_dm_timer_reset(timer);
ret = omap_dm_timer_set_source(timer, OMAP_TIMER_SRC_32_KHZ);
timer->posted = 1;
return ret;
}
static inline u32 omap_dm_timer_reserved_systimer(int id)
{
return (omap_reserved_systimers & (1 << (id - 1))) ? 1 : 0;
}
int omap_dm_timer_reserve_systimer(int id)
{
if (omap_dm_timer_reserved_systimer(id))
return -ENODEV;
omap_reserved_systimers |= (1 << (id - 1));
return 0;
}
struct omap_dm_timer *omap_dm_timer_request(void)
{
struct omap_dm_timer *timer = NULL, *t;
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&dm_timer_lock, flags);
list_for_each_entry(t, &omap_timer_list, node) {
if (t->reserved)
continue;
timer = t;
timer->reserved = 1;
break;
}
spin_unlock_irqrestore(&dm_timer_lock, flags);
if (timer) {
ret = omap_dm_timer_prepare(timer);
if (ret) {
timer->reserved = 0;
timer = NULL;
}
}
if (!timer)
pr_debug("%s: timer request failed!\n", __func__);
return timer;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_request);
struct omap_dm_timer *omap_dm_timer_request_specific(int id)
{
struct omap_dm_timer *timer = NULL, *t;
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&dm_timer_lock, flags);
list_for_each_entry(t, &omap_timer_list, node) {
if (t->pdev->id == id && !t->reserved) {
timer = t;
timer->reserved = 1;
break;
}
}
spin_unlock_irqrestore(&dm_timer_lock, flags);
if (timer) {
ret = omap_dm_timer_prepare(timer);
if (ret) {
timer->reserved = 0;
timer = NULL;
}
}
if (!timer)
pr_debug("%s: timer%d request failed!\n", __func__, id);
return timer;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_request_specific);
int omap_dm_timer_free(struct omap_dm_timer *timer)
{
if (unlikely(!timer))
return -EINVAL;
clk_put(timer->fclk);
WARN_ON(!timer->reserved);
timer->reserved = 0;
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_free);
void omap_dm_timer_enable(struct omap_dm_timer *timer)
{
pm_runtime_get_sync(&timer->pdev->dev);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_enable);
void omap_dm_timer_disable(struct omap_dm_timer *timer)
{
pm_runtime_put_sync(&timer->pdev->dev);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_disable);
int omap_dm_timer_get_irq(struct omap_dm_timer *timer)
{
if (timer)
return timer->irq;
return -EINVAL;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_get_irq);
#if defined(CONFIG_ARCH_OMAP1)
/**
* omap_dm_timer_modify_idlect_mask - Check if any running timers use ARMXOR
* @inputmask: current value of idlect mask
*/
__u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
{
int i = 0;
struct omap_dm_timer *timer = NULL;
unsigned long flags;
/* If ARMXOR cannot be idled this function call is unnecessary */
if (!(inputmask & (1 << 1)))
return inputmask;
/* If any active timer is using ARMXOR return modified mask */
spin_lock_irqsave(&dm_timer_lock, flags);
list_for_each_entry(timer, &omap_timer_list, node) {
u32 l;
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
if (l & OMAP_TIMER_CTRL_ST) {
if (((omap_readl(MOD_CONF_CTRL_1) >> (i * 2)) & 0x03) == 0)
inputmask &= ~(1 << 1);
else
inputmask &= ~(1 << 2);
}
i++;
}
spin_unlock_irqrestore(&dm_timer_lock, flags);
return inputmask;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_modify_idlect_mask);
#else
struct clk *omap_dm_timer_get_fclk(struct omap_dm_timer *timer)
{
if (timer)
return timer->fclk;
return NULL;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_get_fclk);
__u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
{
BUG();
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_modify_idlect_mask);
#endif
int omap_dm_timer_trigger(struct omap_dm_timer *timer)
{
if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
pr_err("%s: timer not available or enabled.\n", __func__);
return -EINVAL;
}
omap_dm_timer_write_reg(timer, OMAP_TIMER_TRIGGER_REG, 0);
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_trigger);
int omap_dm_timer_start(struct omap_dm_timer *timer)
{
u32 l;
if (unlikely(!timer))
return -EINVAL;
omap_dm_timer_enable(timer);
if (!(timer->capability & OMAP_TIMER_ALWON)) {
if (omap_pm_get_dev_context_loss_count(&timer->pdev->dev) !=
timer->ctx_loss_count)
omap_timer_restore_context(timer);
}
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
if (!(l & OMAP_TIMER_CTRL_ST)) {
l |= OMAP_TIMER_CTRL_ST;
omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
}
/* Save the context */
timer->context.tclr = l;
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_start);
int omap_dm_timer_stop(struct omap_dm_timer *timer)
{
unsigned long rate = 0;
if (unlikely(!timer))
return -EINVAL;
if (!(timer->capability & OMAP_TIMER_NEEDS_RESET))
rate = clk_get_rate(timer->fclk);
__omap_dm_timer_stop(timer, timer->posted, rate);
if (!(timer->capability & OMAP_TIMER_ALWON))
timer->ctx_loss_count =
omap_pm_get_dev_context_loss_count(&timer->pdev->dev);
/*
* Since the register values are computed and written within
* __omap_dm_timer_stop, we need to use read to retrieve the
* context.
*/
timer->context.tclr =
omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
timer->context.tisr = __raw_readl(timer->irq_stat);
omap_dm_timer_disable(timer);
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_stop);
int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
{
int ret;
char *parent_name = NULL;
struct clk *fclk, *parent;
struct dmtimer_platform_data *pdata;
if (unlikely(!timer))
return -EINVAL;
pdata = timer->pdev->dev.platform_data;
if (source < 0 || source >= 3)
return -EINVAL;
/*
* FIXME: Used for OMAP1 devices only because they do not currently
* use the clock framework to set the parent clock. To be removed
* once OMAP1 migrated to using clock framework for dmtimers
*/
if (pdata->set_timer_src)
return pdata->set_timer_src(timer->pdev, source);
fclk = clk_get(&timer->pdev->dev, "fck");
if (IS_ERR_OR_NULL(fclk)) {
pr_err("%s: fck not found\n", __func__);
return -EINVAL;
}
switch (source) {
case OMAP_TIMER_SRC_SYS_CLK:
parent_name = "timer_sys_ck";
break;
case OMAP_TIMER_SRC_32_KHZ:
parent_name = "timer_32k_ck";
break;
case OMAP_TIMER_SRC_EXT_CLK:
parent_name = "timer_ext_ck";
break;
}
parent = clk_get(&timer->pdev->dev, parent_name);
if (IS_ERR_OR_NULL(parent)) {
pr_err("%s: %s not found\n", __func__, parent_name);
ret = -EINVAL;
goto out;
}
ret = clk_set_parent(fclk, parent);
if (IS_ERR_VALUE(ret))
pr_err("%s: failed to set %s as parent\n", __func__,
parent_name);
clk_put(parent);
out:
clk_put(fclk);
return ret;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_source);
int omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload,
unsigned int load)
{
u32 l;
if (unlikely(!timer))
return -EINVAL;
omap_dm_timer_enable(timer);
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
if (autoreload)
l |= OMAP_TIMER_CTRL_AR;
else
l &= ~OMAP_TIMER_CTRL_AR;
omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG, load);
omap_dm_timer_write_reg(timer, OMAP_TIMER_TRIGGER_REG, 0);
/* Save the context */
timer->context.tclr = l;
timer->context.tldr = load;
omap_dm_timer_disable(timer);
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_load);
/* Optimized set_load which removes costly spin wait in timer_start */
int omap_dm_timer_set_load_start(struct omap_dm_timer *timer, int autoreload,
unsigned int load)
{
u32 l;
if (unlikely(!timer))
return -EINVAL;
omap_dm_timer_enable(timer);
if (!(timer->capability & OMAP_TIMER_ALWON)) {
if (omap_pm_get_dev_context_loss_count(&timer->pdev->dev) !=
timer->ctx_loss_count)
omap_timer_restore_context(timer);
}
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
if (autoreload) {
l |= OMAP_TIMER_CTRL_AR;
omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG, load);
} else {
l &= ~OMAP_TIMER_CTRL_AR;
}
l |= OMAP_TIMER_CTRL_ST;
__omap_dm_timer_load_start(timer, l, load, timer->posted);
/* Save the context */
timer->context.tclr = l;
timer->context.tldr = load;
timer->context.tcrr = load;
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_load_start);
int omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
unsigned int match)
{
u32 l;
if (unlikely(!timer))
return -EINVAL;
omap_dm_timer_enable(timer);
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
if (enable)
l |= OMAP_TIMER_CTRL_CE;
else
l &= ~OMAP_TIMER_CTRL_CE;
omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG, match);
/* Save the context */
timer->context.tclr = l;
timer->context.tmar = match;
omap_dm_timer_disable(timer);
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_match);
int omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
int toggle, int trigger)
{
u32 l;
if (unlikely(!timer))
return -EINVAL;
omap_dm_timer_enable(timer);
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
l &= ~(OMAP_TIMER_CTRL_GPOCFG | OMAP_TIMER_CTRL_SCPWM |
OMAP_TIMER_CTRL_PT | (0x03 << 10));
if (def_on)
l |= OMAP_TIMER_CTRL_SCPWM;
if (toggle)
l |= OMAP_TIMER_CTRL_PT;
l |= trigger << 10;
omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
/* Save the context */
timer->context.tclr = l;
omap_dm_timer_disable(timer);
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_pwm);
int omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler)
{
u32 l;
if (unlikely(!timer))
return -EINVAL;
omap_dm_timer_enable(timer);
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
l &= ~(OMAP_TIMER_CTRL_PRE | (0x07 << 2));
if (prescaler >= 0x00 && prescaler <= 0x07) {
l |= OMAP_TIMER_CTRL_PRE;
l |= prescaler << 2;
}
omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
/* Save the context */
timer->context.tclr = l;
omap_dm_timer_disable(timer);
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_prescaler);
int omap_dm_timer_set_int_enable(struct omap_dm_timer *timer,
unsigned int value)
{
if (unlikely(!timer))
return -EINVAL;
omap_dm_timer_enable(timer);
__omap_dm_timer_int_enable(timer, value);
/* Save the context */
timer->context.tier = value;
timer->context.twer = value;
omap_dm_timer_disable(timer);
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_int_enable);
unsigned int omap_dm_timer_read_status(struct omap_dm_timer *timer)
{
unsigned int l;
if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
pr_err("%s: timer not available or enabled.\n", __func__);
return 0;
}
l = __raw_readl(timer->irq_stat);
return l;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_read_status);
int omap_dm_timer_write_status(struct omap_dm_timer *timer, unsigned int value)
{
if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev)))
return -EINVAL;
__omap_dm_timer_write_status(timer, value);
/* Save the context */
timer->context.tisr = value;
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_write_status);
unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *timer)
{
if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
pr_err("%s: timer not iavailable or enabled.\n", __func__);
return 0;
}
return __omap_dm_timer_read_counter(timer, timer->posted);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_read_counter);
int omap_dm_timer_write_counter(struct omap_dm_timer *timer, unsigned int value)
{
if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
pr_err("%s: timer not available or enabled.\n", __func__);
return -EINVAL;
}
omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG, value);
/* Save the context */
timer->context.tcrr = value;
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_write_counter);
int omap_dm_timers_active(void)
{
struct omap_dm_timer *timer;
list_for_each_entry(timer, &omap_timer_list, node) {
if (!timer->reserved)
continue;
if (omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG) &
OMAP_TIMER_CTRL_ST) {
return 1;
}
}
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timers_active);
/**
* omap_dm_timer_probe - probe function called for every registered device
* @pdev: pointer to current timer platform device
*
* Called by driver framework at the end of device registration for all
* timer devices.
*/
static int __devinit omap_dm_timer_probe(struct platform_device *pdev)
{
unsigned long flags;
struct omap_dm_timer *timer;
struct resource *mem, *irq;
struct device *dev = &pdev->dev;
struct dmtimer_platform_data *pdata = pdev->dev.platform_data;
if (!pdata) {
dev_err(dev, "%s: no platform data.\n", __func__);
return -ENODEV;
}
irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (unlikely(!irq)) {
dev_err(dev, "%s: no IRQ resource.\n", __func__);
return -ENODEV;
}
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (unlikely(!mem)) {
dev_err(dev, "%s: no memory resource.\n", __func__);
return -ENODEV;
}
timer = devm_kzalloc(dev, sizeof(struct omap_dm_timer), GFP_KERNEL);
if (!timer) {
dev_err(dev, "%s: memory alloc failed!\n", __func__);
return -ENOMEM;
}
timer->io_base = devm_request_and_ioremap(dev, mem);
if (!timer->io_base) {
dev_err(dev, "%s: region already claimed.\n", __func__);
return -ENOMEM;
}
timer->id = pdev->id;
timer->irq = irq->start;
timer->reserved = omap_dm_timer_reserved_systimer(timer->id);
timer->pdev = pdev;
timer->capability = pdata->timer_capability;
/* Skip pm_runtime_enable for OMAP1 */
if (!(timer->capability & OMAP_TIMER_NEEDS_RESET)) {
pm_runtime_enable(dev);
pm_runtime_irq_safe(dev);
}
if (!timer->reserved) {
pm_runtime_get_sync(dev);
__omap_dm_timer_init_regs(timer);
pm_runtime_put(dev);
}
/* add the timer element to the list */
spin_lock_irqsave(&dm_timer_lock, flags);
list_add_tail(&timer->node, &omap_timer_list);
spin_unlock_irqrestore(&dm_timer_lock, flags);
dev_dbg(dev, "Device Probed.\n");
return 0;
}
/**
* omap_dm_timer_remove - cleanup a registered timer device
* @pdev: pointer to current timer platform device
*
* Called by driver framework whenever a timer device is unregistered.
* In addition to freeing platform resources it also deletes the timer
* entry from the local list.
*/
static int __devexit omap_dm_timer_remove(struct platform_device *pdev)
{
struct omap_dm_timer *timer;
unsigned long flags;
int ret = -EINVAL;
spin_lock_irqsave(&dm_timer_lock, flags);
list_for_each_entry(timer, &omap_timer_list, node)
if (timer->pdev->id == pdev->id) {
list_del(&timer->node);
ret = 0;
break;
}
spin_unlock_irqrestore(&dm_timer_lock, flags);
return ret;
}
static struct platform_driver omap_dm_timer_driver = {
.probe = omap_dm_timer_probe,
.remove = __devexit_p(omap_dm_timer_remove),
.driver = {
.name = "omap_timer",
},
};
static int __init omap_dm_timer_driver_init(void)
{
return platform_driver_register(&omap_dm_timer_driver);
}
static void __exit omap_dm_timer_driver_exit(void)
{
platform_driver_unregister(&omap_dm_timer_driver);
}
early_platform_init("earlytimer", &omap_dm_timer_driver);
module_init(omap_dm_timer_driver_init);
module_exit(omap_dm_timer_driver_exit);
MODULE_DESCRIPTION("OMAP Dual-Mode Timer Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRIVER_NAME);
MODULE_AUTHOR("Texas Instruments Inc");