1 /* 2 * Copyright 2012 Calxeda, Inc. 3 * 4 * Based on arch/arm/plat-mxc/cpuidle.c: #v3.7 5 * Copyright 2012 Freescale Semiconductor, Inc. 6 * Copyright 2012 Linaro Ltd. 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms and conditions of the GNU General Public License, 10 * version 2, as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope it will be useful, but WITHOUT 13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 15 * more details. 16 * 17 * You should have received a copy of the GNU General Public License along with 18 * this program. If not, see <http://www.gnu.org/licenses/>. 19 * 20 * Maintainer: Rob Herring <rob.herring@calxeda.com> 21 */ 22 23 #include <linux/cpuidle.h> 24 #include <linux/cpu_pm.h> 25 #include <linux/init.h> 26 #include <linux/mm.h> 27 #include <linux/platform_device.h> 28 #include <asm/cpuidle.h> 29 #include <asm/suspend.h> 30 #include <asm/psci.h> 31 32 static int calxeda_idle_finish(unsigned long val) 33 { 34 const struct psci_power_state ps = { 35 .type = PSCI_POWER_STATE_TYPE_POWER_DOWN, 36 }; 37 return psci_ops.cpu_suspend(ps, __pa(cpu_resume)); 38 } 39 40 static int calxeda_pwrdown_idle(struct cpuidle_device *dev, 41 struct cpuidle_driver *drv, 42 int index) 43 { 44 cpu_pm_enter(); 45 cpu_suspend(0, calxeda_idle_finish); 46 cpu_pm_exit(); 47 48 return index; 49 } 50 51 static struct cpuidle_driver calxeda_idle_driver = { 52 .name = "calxeda_idle", 53 .states = { 54 ARM_CPUIDLE_WFI_STATE, 55 { 56 .name = "PG", 57 .desc = "Power Gate", 58 .flags = CPUIDLE_FLAG_TIME_VALID, 59 .exit_latency = 30, 60 .power_usage = 50, 61 .target_residency = 200, 62 .enter = calxeda_pwrdown_idle, 63 }, 64 }, 65 .state_count = 2, 66 }; 67 68 static int __init calxeda_cpuidle_probe(struct platform_device *pdev) 69 { 70 return cpuidle_register(&calxeda_idle_driver, NULL); 71 } 72 73 static struct platform_driver calxeda_cpuidle_plat_driver = { 74 .driver = { 75 .name = "cpuidle-calxeda", 76 .owner = THIS_MODULE, 77 }, 78 .probe = calxeda_cpuidle_probe, 79 }; 80 81 module_platform_driver(calxeda_cpuidle_plat_driver); 82