| 1 | /* |
| 2 | * Copyright (C) STMicroelectronics 2009 |
| 3 | * Copyright (C) ST-Ericsson SA 2010-2012 |
| 4 | * |
| 5 | * License Terms: GNU General Public License v2 |
| 6 | * Author: Sundar Iyer <sundar.iyer@stericsson.com> |
| 7 | * Author: Martin Persson <martin.persson@stericsson.com> |
| 8 | * Author: Jonas Aaberg <jonas.aberg@stericsson.com> |
| 9 | */ |
| 10 | |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/cpufreq.h> |
| 14 | #include <linux/delay.h> |
| 15 | #include <linux/slab.h> |
| 16 | #include <linux/platform_device.h> |
| 17 | #include <linux/clk.h> |
| 18 | |
| 19 | static struct cpufreq_frequency_table *freq_table; |
| 20 | static struct clk *armss_clk; |
| 21 | |
| 22 | static int dbx500_cpufreq_target(struct cpufreq_policy *policy, |
| 23 | unsigned int index) |
| 24 | { |
| 25 | /* update armss clk frequency */ |
| 26 | return clk_set_rate(armss_clk, freq_table[index].frequency * 1000); |
| 27 | } |
| 28 | |
| 29 | static int dbx500_cpufreq_init(struct cpufreq_policy *policy) |
| 30 | { |
| 31 | policy->clk = armss_clk; |
| 32 | return cpufreq_generic_init(policy, freq_table, 20 * 1000); |
| 33 | } |
| 34 | |
| 35 | static struct cpufreq_driver dbx500_cpufreq_driver = { |
| 36 | .flags = CPUFREQ_STICKY | CPUFREQ_CONST_LOOPS | |
| 37 | CPUFREQ_NEED_INITIAL_FREQ_CHECK, |
| 38 | .verify = cpufreq_generic_frequency_table_verify, |
| 39 | .target_index = dbx500_cpufreq_target, |
| 40 | .get = cpufreq_generic_get, |
| 41 | .init = dbx500_cpufreq_init, |
| 42 | .name = "DBX500", |
| 43 | .attr = cpufreq_generic_attr, |
| 44 | }; |
| 45 | |
| 46 | static int dbx500_cpufreq_probe(struct platform_device *pdev) |
| 47 | { |
| 48 | struct cpufreq_frequency_table *pos; |
| 49 | |
| 50 | freq_table = dev_get_platdata(&pdev->dev); |
| 51 | if (!freq_table) { |
| 52 | pr_err("dbx500-cpufreq: Failed to fetch cpufreq table\n"); |
| 53 | return -ENODEV; |
| 54 | } |
| 55 | |
| 56 | armss_clk = clk_get(&pdev->dev, "armss"); |
| 57 | if (IS_ERR(armss_clk)) { |
| 58 | pr_err("dbx500-cpufreq: Failed to get armss clk\n"); |
| 59 | return PTR_ERR(armss_clk); |
| 60 | } |
| 61 | |
| 62 | pr_info("dbx500-cpufreq: Available frequencies:\n"); |
| 63 | cpufreq_for_each_entry(pos, freq_table) |
| 64 | pr_info(" %d Mhz\n", pos->frequency / 1000); |
| 65 | |
| 66 | return cpufreq_register_driver(&dbx500_cpufreq_driver); |
| 67 | } |
| 68 | |
| 69 | static struct platform_driver dbx500_cpufreq_plat_driver = { |
| 70 | .driver = { |
| 71 | .name = "cpufreq-ux500", |
| 72 | }, |
| 73 | .probe = dbx500_cpufreq_probe, |
| 74 | }; |
| 75 | |
| 76 | static int __init dbx500_cpufreq_register(void) |
| 77 | { |
| 78 | return platform_driver_register(&dbx500_cpufreq_plat_driver); |
| 79 | } |
| 80 | device_initcall(dbx500_cpufreq_register); |
| 81 | |
| 82 | MODULE_LICENSE("GPL v2"); |
| 83 | MODULE_DESCRIPTION("cpufreq driver for DBX500"); |