Merge branches 'acpi-x86', 'acpi-dptf' and 'acpi-apei'

[linux-2.6-block.git] / drivers / acpi / x86 / cmos_rtc.c

diff --git a/drivers/acpi/x86/cmos_rtc.c b/drivers/acpi/x86/cmos_rtc.c
new file mode 100644 (file)
index 0000000..51643ff
--- /dev/null
+++ b/drivers/acpi/x86/cmos_rtc.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ACPI support for CMOS RTC Address Space access
+ *
+ * Copyright (C) 2013, Intel Corporation
+ * Authors: Lan Tianyu <tianyu.lan@intel.com>
+ */
+
+#define pr_fmt(fmt) "ACPI: " fmt
+
+#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"
+
+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;
+}
+
+int acpi_install_cmos_rtc_space_handler(acpi_handle handle)
+{
+       acpi_status status;
+
+       status = acpi_install_address_space_handler(handle,
+                       ACPI_ADR_SPACE_CMOS,
+                       &acpi_cmos_rtc_space_handler,
+                       NULL, NULL);
+       if (ACPI_FAILURE(status)) {
+               pr_err("Error installing CMOS-RTC region handler\n");
+               return -ENODEV;
+       }
+
+       return 1;
+}
+EXPORT_SYMBOL_GPL(acpi_install_cmos_rtc_space_handler);
+
+void acpi_remove_cmos_rtc_space_handler(acpi_handle handle)
+{
+       if (ACPI_FAILURE(acpi_remove_address_space_handler(handle,
+                       ACPI_ADR_SPACE_CMOS, &acpi_cmos_rtc_space_handler)))
+               pr_err("Error removing CMOS-RTC region handler\n");
+}
+EXPORT_SYMBOL_GPL(acpi_remove_cmos_rtc_space_handler);
+
+static int acpi_cmos_rtc_attach_handler(struct acpi_device *adev, const struct acpi_device_id *id)
+{
+       return acpi_install_cmos_rtc_space_handler(adev->handle);
+}
+
+static void acpi_cmos_rtc_detach_handler(struct acpi_device *adev)
+{
+       acpi_remove_cmos_rtc_space_handler(adev->handle);
+}
+
+static struct acpi_scan_handler cmos_rtc_handler = {
+       .ids = acpi_cmos_rtc_ids,
+       .attach = acpi_cmos_rtc_attach_handler,
+       .detach = acpi_cmos_rtc_detach_handler,
+};
+
+void __init acpi_cmos_rtc_init(void)
+{
+       acpi_scan_add_handler(&cmos_rtc_handler);
+}