ARM: at91: cpuidle: Convert to platform driver
Using the platform driver model is a good way to separate the cpuidle specific
code from the low level pm code. It allows to remove the dependency between
these two components.
The platform_device is located in the pm code and a 'set' function has been
added to set the standby function from the AT91_SOC_START initialization
function. Each SoC with a cpuidle driver will set the standby function in the
platform_data field at init time. Then pm code will register the cpuidle
platform device.
The cpuidle driver will register the platform_driver and use the device's
platform_data as a standby callback in the idle path.
The at91_pm_enter function contains a { if then else } based on cpu_is_xx
similar to what was in cpuidle. This is considered dangerous when adding a new
SoC. Like the cpuidle driver, a standby ops is defined and assigned when the
SoC init function specifies what is its standby function and reused in the
at91_pm_enter's 'case' block.
Signed-off-by: Daniel Lezcano <[email protected]>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <[email protected]>
Acked-by: Nicolas Ferre <[email protected]>
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index 15afb5d..9986542 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -39,6 +39,8 @@
#include "at91_rstc.h"
#include "at91_shdwc.h"
+static void (*at91_pm_standby)(void);
+
static void __init show_reset_status(void)
{
static char reset[] __initdata = "reset";
@@ -266,14 +268,8 @@
* For ARM 926 based chips, this requirement is weaker
* as at91sam9 can access a RAM in self-refresh mode.
*/
- if (cpu_is_at91rm9200())
- at91rm9200_standby();
- else if (cpu_is_at91sam9g45())
- at91sam9g45_standby();
- else if (cpu_is_at91sam9263())
- at91sam9263_standby();
- else
- at91sam9_standby();
+ if (at91_pm_standby)
+ at91_pm_standby();
break;
case PM_SUSPEND_ON:
@@ -314,6 +310,18 @@
.end = at91_pm_end,
};
+static struct platform_device at91_cpuidle_device = {
+ .name = "cpuidle-at91",
+};
+
+void at91_pm_set_standby(void (*at91_standby)(void))
+{
+ if (at91_standby) {
+ at91_cpuidle_device.dev.platform_data = at91_standby;
+ at91_pm_standby = at91_standby;
+ }
+}
+
static int __init at91_pm_init(void)
{
#ifdef CONFIG_AT91_SLOW_CLOCK
@@ -325,6 +333,9 @@
/* AT91RM9200 SDRAM low-power mode cannot be used with self-refresh. */
if (cpu_is_at91rm9200())
at91_ramc_write(0, AT91RM9200_SDRAMC_LPR, 0);
+
+ if (at91_cpuidle_device.dev.platform_data)
+ platform_device_register(&at91_cpuidle_device);
suspend_set_ops(&at91_pm_ops);