[PATCH 2/2] cpufreq: cppc: convert to a platform driver

Mian Yousaf Kaukab
2020-12-10T14:24:13Z

From: Mian Yousaf Kaukab <ykaukab@suse.de>

Instead of piggybacking on ACPI_PROCESSOR_DEVICE_HID, convert the driver
to a proper platform driver with its own ID. Driver will only be probed
when cppc-cpufreq device is available.

Fixes: 28f06f770454 ("cppc_cpufreq: replace per-cpu structures with lists")
Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
---
drivers/cpufreq/cppc_cpufreq.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index bb4c068601db..defac1dd9a2a 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -11,13 +11,13 @@
#define pr_fmt(fmt) "CPPC Cpufreq:" fmt

#include <linux/kernel.h>
-#include <linux/module.h>
#include <linux/delay.h>
#include <linux/cpu.h>
#include <linux/cpufreq.h>
#include <linux/dmi.h>
#include <linux/time.h>
#include <linux/vmalloc.h>
+#include <linux/platform_device.h>

#include <asm/unaligned.h>

@@ -512,7 +512,7 @@ static void cppc_check_hisi_workaround(void)
acpi_put_table(tbl);
}

-static int __init cppc_cpufreq_init(void)
+static int cppc_cpufreq_probe(struct platform_device *pdev)
{
if (acpi_disabled)
return -ENODEV;
@@ -533,26 +533,27 @@ static inline void free_cpu_data(void)
list_del(&iter->node);
kfree(iter);
}
-
}

-static void __exit cppc_cpufreq_exit(void)
+static int cppc_cpufreq_remove(struct platform_device *pdev)
{
cpufreq_unregister_driver(&cppc_cpufreq_driver);

free_cpu_data();
+
+ return 0;
}

-module_exit(cppc_cpufreq_exit);
+static struct platform_driver cppc_cpufreq_platform_driver = {
+ .driver = {
+ .name = "cppc-cpufreq",
+ },
+ .probe = cppc_cpufreq_probe,
+ .remove = cppc_cpufreq_remove,
+};
+module_platform_driver(cppc_cpufreq_platform_driver);
+
+MODULE_ALIAS("platform:cppc-cpufreq");
MODULE_AUTHOR("Ashwin Chaugule");
MODULE_DESCRIPTION("CPUFreq driver based on the ACPI CPPC v5.0+ spec");
MODULE_LICENSE("GPL");
-
-late_initcall(cppc_cpufreq_init);
-
-static const struct acpi_device_id cppc_acpi_ids[] __used = {
- {ACPI_PROCESSOR_DEVICE_HID, },
- {}
-};
-
-MODULE_DEVICE_TABLE(acpi, cppc_acpi_ids);
--
2.26.2