/* * based on arch/arm/mach-kirkwood/cpuidle.c * * CPU idle support for AT91 SoC * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. * * The cpu idle uses wait-for-interrupt and RAM self refresh in order * to implement two idle states - * #1 wait-for-interrupt * #2 wait-for-interrupt and RAM self refresh */ #include <linux/kernel.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/cpuidle.h> #include <linux/io.h> #include <linux/export.h> #include <asm/proc-fns.h> #include <asm/cpuidle.h> #include <mach/cpu.h> #include "pm.h" #define AT91_MAX_STATES 2 /* Actual code that puts the SoC in different idle states */ static int at91_enter_idle(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { if (cpu_is_at91rm9200()) at91rm9200_standby(); else if (cpu_is_at91sam9g45()) at91sam9g45_standby(); else if (cpu_is_at91sam9263()) at91sam9263_standby(); else at91sam9_standby(); return index; } static struct cpuidle_driver at91_idle_driver = { .name = "at91_idle", .owner = THIS_MODULE, .states[0] = ARM_CPUIDLE_WFI_STATE, .states[1] = { .enter = at91_enter_idle, .exit_latency = 10, .target_residency = 100000, .flags = CPUIDLE_FLAG_TIME_VALID, .name = "RAM_SR", .desc = "WFI and DDR Self Refresh", }, .state_count = AT91_MAX_STATES, }; /* Initialize CPU idle by registering the idle states */ static int __init at91_init_cpuidle(void) { return cpuidle_register(&at91_idle_driver, NULL); } device_initcall(at91_init_cpuidle);