Commit 1ae2f435 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

ACPI: x86: cmos_rtc: Create a CMOS RTC platform device 



Make the CMOS RTC ACPI scan handler create a platform device that will
be used subsequently by rtc-cmos for driver binding on x86 systems with
ACPI and update add_rtc_cmos() to skip registering a fallback platform
device for the CMOS RTC when the above one has been registered.

Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com> # x86
Link: https://patch.msgid.link/1962427.tdWV9SEqCh@rafael.j.wysocki
parent 6cee29ad

arch/x86/kernel/rtc.c

+4 −0
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 
/*

 * RTC related functions

 */

#include <linux/acpi.h>

#include <linux/platform_device.h>

#include <linux/mc146818rtc.h>

#include <linux/export.h>
@@ -146,6 +147,9 @@ static __init int add_rtc_cmos(void) 
		}

	}

#endif

	if (cmos_rtc_platform_device_present)

		return 0;



	if (!x86_platform.legacy.rtc)

		return -ENODEV;

drivers/acpi/x86/cmos_rtc.c

+8 −0
Original line number Diff line number Diff line
@@ -24,6 +24,8 @@ static const struct acpi_device_id acpi_cmos_rtc_ids[] = { 
	{}

};



bool cmos_rtc_platform_device_present;



static bool cmos_rtc_space_handler_present __read_mostly;



static acpi_status acpi_cmos_rtc_space_handler(u32 function,
@@ -103,6 +105,12 @@ static int acpi_cmos_rtc_attach(struct acpi_device *adev, 
	if (ret < 0)

		return ret;



	if (IS_ERR_OR_NULL(acpi_create_platform_device(adev, NULL))) {

		pr_err("Failed to create CMOS-RTC platform device\n");

		return 0;

	} else {

		cmos_rtc_platform_device_present = true;

	}

	return 1;

}

include/linux/acpi.h

+4 −0
Original line number Diff line number Diff line
@@ -791,6 +791,8 @@ const char *acpi_get_subsystem_id(acpi_handle handle); 
int acpi_mrrm_max_mem_region(void);

#endif



extern bool cmos_rtc_platform_device_present;



#else	/* !CONFIG_ACPI */



#define acpi_disabled 1
@@ -1116,6 +1118,8 @@ static inline int acpi_mrrm_max_mem_region(void) 
	return 1;

}



#define cmos_rtc_platform_device_present	false



#endif	/* !CONFIG_ACPI */



#ifdef CONFIG_ACPI_HMAT