Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/cpufreq/raspberrypi-cpufreq.c b/drivers/cpufreq/raspberrypi-cpufreq.c
new file mode 100644
index 0000000..2bc7d97
--- /dev/null
+++ b/drivers/cpufreq/raspberrypi-cpufreq.c
@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Raspberry Pi cpufreq driver
+ *
+ * Copyright (C) 2019, Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
+ */
+
+#include <linux/clk.h>
+#include <linux/cpu.h>
+#include <linux/cpufreq.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+
+#define RASPBERRYPI_FREQ_INTERVAL 100000000
+
+static struct platform_device *cpufreq_dt;
+
+static int raspberrypi_cpufreq_probe(struct platform_device *pdev)
+{
+ struct device *cpu_dev;
+ unsigned long min, max;
+ unsigned long rate;
+ struct clk *clk;
+ int ret;
+
+ cpu_dev = get_cpu_device(0);
+ if (!cpu_dev) {
+ pr_err("Cannot get CPU for cpufreq driver\n");
+ return -ENODEV;
+ }
+
+ clk = clk_get(cpu_dev, NULL);
+ if (IS_ERR(clk)) {
+ dev_err(cpu_dev, "Cannot get clock for CPU0\n");
+ return PTR_ERR(clk);
+ }
+
+ /*
+ * The max and min frequencies are configurable in the Raspberry Pi
+ * firmware, so we query them at runtime.
+ */
+ min = roundup(clk_round_rate(clk, 0), RASPBERRYPI_FREQ_INTERVAL);
+ max = roundup(clk_round_rate(clk, ULONG_MAX), RASPBERRYPI_FREQ_INTERVAL);
+ clk_put(clk);
+
+ for (rate = min; rate <= max; rate += RASPBERRYPI_FREQ_INTERVAL) {
+ ret = dev_pm_opp_add(cpu_dev, rate, 0);
+ if (ret)
+ goto remove_opp;
+ }
+
+ cpufreq_dt = platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
+ ret = PTR_ERR_OR_ZERO(cpufreq_dt);
+ if (ret) {
+ dev_err(cpu_dev, "Failed to create platform device, %d\n", ret);
+ goto remove_opp;
+ }
+
+ return 0;
+
+remove_opp:
+ dev_pm_opp_remove_all_dynamic(cpu_dev);
+
+ return ret;
+}
+
+static int raspberrypi_cpufreq_remove(struct platform_device *pdev)
+{
+ struct device *cpu_dev;
+
+ cpu_dev = get_cpu_device(0);
+ if (cpu_dev)
+ dev_pm_opp_remove_all_dynamic(cpu_dev);
+
+ platform_device_unregister(cpufreq_dt);
+
+ return 0;
+}
+
+/*
+ * Since the driver depends on clk-raspberrypi, which may return EPROBE_DEFER,
+ * all the activity is performed in the probe, which may be defered as well.
+ */
+static struct platform_driver raspberrypi_cpufreq_driver = {
+ .driver = {
+ .name = "raspberrypi-cpufreq",
+ },
+ .probe = raspberrypi_cpufreq_probe,
+ .remove = raspberrypi_cpufreq_remove,
+};
+module_platform_driver(raspberrypi_cpufreq_driver);
+
+MODULE_AUTHOR("Nicolas Saenz Julienne <nsaenzjulienne@suse.de");
+MODULE_DESCRIPTION("Raspberry Pi cpufreq driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:raspberrypi-cpufreq");