projects / mirror_ubuntu-artful-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 8def3103 SH |
1 | /* |
| 2 | * System Control and Power Interface (SCPI) based CPUFreq Interface driver | |
| 3 | * | |
| 4 | * It provides necessary ops to arm_big_little cpufreq driver. | |
| 5 | * | |
| 6 | * Copyright (C) 2015 ARM Ltd. | |
| 7 | * Sudeep Holla <sudeep.holla@arm.com> | |
| 8 | * | |
| 9 | * This program is free software; you can redistribute it and/or modify | |
| 10 | * it under the terms of the GNU General Public License version 2 as | |
| 11 | * published by the Free Software Foundation. | |
| 12 | * | |
| 13 | * This program is distributed "as is" WITHOUT ANY WARRANTY of any | |
| 14 | * kind, whether express or implied; without even the implied warranty | |
| 15 | * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 16 | * GNU General Public License for more details. | |
| 17 | */ | |
| 18 | ||
| 19 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
| 20 | ||
| d9975b0b | 21 | #include <linux/cpu.h> |
| 8def3103 SH |
22 | #include <linux/cpufreq.h> |
| 23 | #include <linux/module.h> | |
| 24 | #include <linux/platform_device.h> | |
| 25 | #include <linux/pm_opp.h> | |
| 26 | #include <linux/scpi_protocol.h> | |
| 27 | #include <linux/types.h> | |
| 28 | ||
| 29 | #include "arm_big_little.h" | |
| 30 | ||
| 31 | static struct scpi_ops *scpi_ops; | |
| 32 | ||
| d9975b0b | 33 | static int scpi_get_transition_latency(struct device *cpu_dev) |
| 8def3103 | 34 | { |
| c0f2e219 | 35 | return scpi_ops->get_transition_latency(cpu_dev); |
| d9975b0b SH |
36 | } |
| 37 | ||
| 38 | static int scpi_init_opp_table(const struct cpumask *cpumask) | |
| 39 | { | |
| c0f2e219 | 40 | int ret; |
| d9975b0b | 41 | struct device *cpu_dev = get_cpu_device(cpumask_first(cpumask)); |
| 8def3103 | 42 | |
| c0f2e219 SH |
43 | ret = scpi_ops->add_opps_to_device(cpu_dev); |
| 44 | if (ret) { | |
| 45 | dev_warn(cpu_dev, "failed to add opps to the device\n"); | |
| 46 | return ret; | |
| 8def3103 | 47 | } |
| 8def3103 | 48 | |
| d9975b0b SH |
49 | ret = dev_pm_opp_set_sharing_cpus(cpu_dev, cpumask); |
| 50 | if (ret) | |
| 51 | dev_err(cpu_dev, "%s: failed to mark OPPs as shared: %d\n", | |
| 52 | __func__, ret); | |
| 53 | return ret; | |
| 8def3103 SH |
54 | } |
| 55 | ||
| 56 | static struct cpufreq_arm_bL_ops scpi_cpufreq_ops = { | |
| 57 | .name = "scpi", | |
| 58 | .get_transition_latency = scpi_get_transition_latency, | |
| 59 | .init_opp_table = scpi_init_opp_table, | |
| d9975b0b | 60 | .free_opp_table = dev_pm_opp_cpumask_remove_table, |
| 8def3103 SH |
61 | }; |
| 62 | ||
| 63 | static int scpi_cpufreq_probe(struct platform_device *pdev) | |
| 64 | { | |
| 65 | scpi_ops = get_scpi_ops(); | |
| 66 | if (!scpi_ops) | |
| 67 | return -EIO; | |
| 68 | ||
| 69 | return bL_cpufreq_register(&scpi_cpufreq_ops); | |
| 70 | } | |
| 71 | ||
| 72 | static int scpi_cpufreq_remove(struct platform_device *pdev) | |
| 73 | { | |
| 74 | bL_cpufreq_unregister(&scpi_cpufreq_ops); | |
| 75 | scpi_ops = NULL; | |
| 76 | return 0; | |
| 77 | } | |
| 78 | ||
| 79 | static struct platform_driver scpi_cpufreq_platdrv = { | |
| 80 | .driver = { | |
| 81 | .name = "scpi-cpufreq", | |
| 8def3103 SH |
82 | }, |
| 83 | .probe = scpi_cpufreq_probe, | |
| 84 | .remove = scpi_cpufreq_remove, | |
| 85 | }; | |
| 86 | module_platform_driver(scpi_cpufreq_platdrv); | |
| 87 | ||
| 88 | MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>"); | |
| 89 | MODULE_DESCRIPTION("ARM SCPI CPUFreq interface driver"); | |
| 90 | MODULE_LICENSE("GPL v2"); |