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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/acpi/acpi_cmos_rtc.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/acpi/acpi_cmos_rtc.c')
-rw-r--r-- | drivers/acpi/acpi_cmos_rtc.c | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/drivers/acpi/acpi_cmos_rtc.c b/drivers/acpi/acpi_cmos_rtc.c new file mode 100644 index 000000000..0980a1339 --- /dev/null +++ b/drivers/acpi/acpi_cmos_rtc.c @@ -0,0 +1,90 @@ +/* + * ACPI support for CMOS RTC Address Space access + * + * Copyright (C) 2013, Intel Corporation + * Authors: Lan Tianyu <tianyu.lan@intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/acpi.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mc146818rtc.h> + +#include "internal.h" + +ACPI_MODULE_NAME("cmos rtc"); + +static const struct acpi_device_id acpi_cmos_rtc_ids[] = { + { "PNP0B00" }, + { "PNP0B01" }, + { "PNP0B02" }, + {} +}; + +static acpi_status +acpi_cmos_rtc_space_handler(u32 function, acpi_physical_address address, + u32 bits, u64 *value64, + void *handler_context, void *region_context) +{ + int i; + u8 *value = (u8 *)value64; + + if (address > 0xff || !value64) + return AE_BAD_PARAMETER; + + if (function != ACPI_WRITE && function != ACPI_READ) + return AE_BAD_PARAMETER; + + spin_lock_irq(&rtc_lock); + + for (i = 0; i < DIV_ROUND_UP(bits, 8); ++i, ++address, ++value) + if (function == ACPI_READ) + *value = CMOS_READ(address); + else + CMOS_WRITE(*value, address); + + spin_unlock_irq(&rtc_lock); + + return AE_OK; +} + +static int acpi_install_cmos_rtc_space_handler(struct acpi_device *adev, + const struct acpi_device_id *id) +{ + acpi_status status; + + status = acpi_install_address_space_handler(adev->handle, + ACPI_ADR_SPACE_CMOS, + &acpi_cmos_rtc_space_handler, + NULL, NULL); + if (ACPI_FAILURE(status)) { + pr_err(PREFIX "Error installing CMOS-RTC region handler\n"); + return -ENODEV; + } + + return 1; +} + +static void acpi_remove_cmos_rtc_space_handler(struct acpi_device *adev) +{ + if (ACPI_FAILURE(acpi_remove_address_space_handler(adev->handle, + ACPI_ADR_SPACE_CMOS, &acpi_cmos_rtc_space_handler))) + pr_err(PREFIX "Error removing CMOS-RTC region handler\n"); +} + +static struct acpi_scan_handler cmos_rtc_handler = { + .ids = acpi_cmos_rtc_ids, + .attach = acpi_install_cmos_rtc_space_handler, + .detach = acpi_remove_cmos_rtc_space_handler, +}; + +void __init acpi_cmos_rtc_init(void) +{ + acpi_scan_add_handler(&cmos_rtc_handler); +} |