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authorLan Tianyu <tianyu.lan@intel.com>2013-06-05 02:27:50 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-07-21 18:21:28 -0700
commit623c1cba04991c15d594a25fd31d7480d931aa57 (patch)
treef82e520cd4fa829712db79930782355b0822b5d5
parente64c0641beee09a0d9870efc5ea40eb06b6529cb (diff)
downloadvexpress-lsk-623c1cba04991c15d594a25fd31d7480d931aa57.tar.gz
ACPI: Add CMOS RTC Operation Region handler support
commit 2fa97feb4406c546b52e35b6b6c50cb8f63425d2 upstream. On HP Folio 13-2000, the BIOS defines a CMOS RTC Operation Region and the EC's _REG methord accesses that region. Thus an appropriate address space handler must be registered for that region before the EC driver is loaded. Introduce a mechanism for adding CMOS RTC address space handlers. Register an ACPI scan handler for CMOS RTC devices such that, when a device of that kind is detected during an ACPI namespace scan, a common CMOS RTC operation region address space handler will be installed for it. References: https://bugzilla.kernel.org/show_bug.cgi?id=54621 Reported-and-tested-by: Stefan Nagy <public@stefan-nagy.at> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/acpi/Makefile1
-rw-r--r--drivers/acpi/acpi_cmos_rtc.c92
-rw-r--r--drivers/acpi/internal.h5
-rw-r--r--drivers/acpi/scan.c1
4 files changed, 99 insertions, 0 deletions
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 536562c626a..97c949abfab 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -43,6 +43,7 @@ acpi-y += acpi_platform.o
acpi-y += power.o
acpi-y += event.o
acpi-y += sysfs.o
+acpi-$(CONFIG_X86) += acpi_cmos_rtc.o
acpi-$(CONFIG_DEBUG_FS) += debugfs.o
acpi-$(CONFIG_ACPI_NUMA) += numa.o
acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
diff --git a/drivers/acpi/acpi_cmos_rtc.c b/drivers/acpi/acpi_cmos_rtc.c
new file mode 100644
index 00000000000..84190ed89c0
--- /dev/null
+++ b/drivers/acpi/acpi_cmos_rtc.c
@@ -0,0 +1,92 @@
+/*
+ * 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 <asm-generic/rtc.h>
+
+#include "internal.h"
+
+#define PREFIX "ACPI: "
+
+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 0;
+}
+
+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);
+}
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index c610a76d92c..63a08549bfa 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -50,6 +50,11 @@ void acpi_memory_hotplug_init(void);
#else
static inline void acpi_memory_hotplug_init(void) {}
#endif
+#ifdef CONFIG_X86
+void acpi_cmos_rtc_init(void);
+#else
+static inline void acpi_cmos_rtc_init(void) {}
+#endif
void acpi_sysfs_add_hotplug_profile(struct acpi_hotplug_profile *hotplug,
const char *name);
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 27da63061e1..14807e53cca 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -2040,6 +2040,7 @@ int __init acpi_scan_init(void)
acpi_pci_link_init();
acpi_platform_init();
acpi_lpss_init();
+ acpi_cmos_rtc_init();
acpi_container_init();
acpi_memory_hotplug_init();
acpi_dock_init();