/* * Versatile Express SPC CPUFreq Interface driver * * It provides necessary ops to arm_big_little cpufreq driver. * * Copyright (C) 2013 ARM Ltd. * Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed "as is" WITHOUT ANY WARRANTY of any * kind, whether express or implied; without even the implied warranty * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/cpu.h> #include <linux/cpufreq.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/pm_opp.h> #include <linux/types.h> #include "arm_big_little.h" static int ve_spc_init_opp_table(const struct cpumask *cpumask) { struct device *cpu_dev = get_cpu_device(cpumask_first(cpumask)); /* * platform specific SPC code must initialise the opp table * so just check if the OPP count is non-zero */ return dev_pm_opp_get_opp_count(cpu_dev) <= 0; } static int ve_spc_get_transition_latency(struct device *cpu_dev) { return 1000000; /* 1 ms */ } static const struct cpufreq_arm_bL_ops ve_spc_cpufreq_ops = { .name = "vexpress-spc", .get_transition_latency = ve_spc_get_transition_latency, .init_opp_table = ve_spc_init_opp_table, }; static int ve_spc_cpufreq_probe(struct platform_device *pdev) { return bL_cpufreq_register(&ve_spc_cpufreq_ops); } static int ve_spc_cpufreq_remove(struct platform_device *pdev) { bL_cpufreq_unregister(&ve_spc_cpufreq_ops); return 0; } static struct platform_driver ve_spc_cpufreq_platdrv = { .driver = { .name = "vexpress-spc-cpufreq", }, .probe = ve_spc_cpufreq_probe, .remove = ve_spc_cpufreq_remove, }; module_platform_driver(ve_spc_cpufreq_platdrv); MODULE_LICENSE("GPL");