misc/pvpanic: split-up generic and platform dependent code

Split-up generic and platform dependent code in order to be able to re-use
generic event handling code in pvpanic PCI device driver in the next patches.

The code from pvpanic.c was split in two new files:
- pvpanic.c: generic code that handles pvpanic events
- pvpanic-mmio.c: platform/bus dependent code

Signed-off-by: Mihai Carabas <mihai.carabas@oracle.com>
Link: https://lore.kernel.org/r/1616597356-20696-2-git-send-email-mihai.carabas@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

7 files changed, 139 insertions, 51 deletions

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index f532c59bb59b..c5f20e939ca3 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -427,14 +427,6 @@ config MISC_RTSX
 	tristate
 	default MISC_RTSX_PCI || MISC_RTSX_USB
 
-config PVPANIC
-	tristate "pvpanic device support"
-	depends on HAS_IOMEM && (ACPI || OF)
-	help
-	  This driver provides support for the pvpanic device.  pvpanic is
-	  a paravirtualized device provided by QEMU; it lets a virtual machine
-	  (guest) communicate panic events to the host.
-
 config HISI_HIKEY_USB
 	tristate "USB GPIO Hub on HiSilicon Hikey 960/970 Platform"
 	depends on (OF && GPIOLIB) || COMPILE_TEST
@@ -461,4 +453,5 @@ source "drivers/misc/bcm-vk/Kconfig"
 source "drivers/misc/cardreader/Kconfig"
 source "drivers/misc/habanalabs/Kconfig"
 source "drivers/misc/uacce/Kconfig"
+source "drivers/misc/pvpanic/Kconfig"
 endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 99b6f15a3c70..fd5f87e149c5 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -51,7 +51,7 @@ obj-$(CONFIG_PCI_ENDPOINT_TEST)	+= pci_endpoint_test.o
 obj-$(CONFIG_OCXL)		+= ocxl/
 obj-$(CONFIG_BCM_VK)		+= bcm-vk/
 obj-y				+= cardreader/
-obj-$(CONFIG_PVPANIC)   	+= pvpanic.o
+obj-$(CONFIG_PVPANIC)   	+= pvpanic/
 obj-$(CONFIG_HABANA_AI)		+= habanalabs/
 obj-$(CONFIG_UACCE)		+= uacce/
 obj-$(CONFIG_XILINX_SDFEC)	+= xilinx_sdfec.o
diff --git a/drivers/misc/pvpanic/Kconfig b/drivers/misc/pvpanic/Kconfig
new file mode 100644
index 000000000000..454f1ee62b72
--- /dev/null
+++ b/drivers/misc/pvpanic/Kconfig
@@ -0,0 +1,19 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Pvpanic Kconfig
+#
+# Copyright (C) 2021 Oracle.
+#
+
+config PVPANIC
+	bool "pvpanic device support"
+	help
+	  This option allows to select a specific pvpanic device driver.
+	  pvpanic is a paravirtualized device provided by QEMU; it lets
+	  a virtual machine (guest) communicate panic events to the host.
+
+config PVPANIC_MMIO
+	tristate "pvpanic MMIO device support"
+	depends on HAS_IOMEM && (ACPI || OF) && PVPANIC
+	help
+	  This driver provides support for the MMIO pvpanic device.
diff --git a/drivers/misc/pvpanic/Makefile b/drivers/misc/pvpanic/Makefile
new file mode 100644
index 000000000000..e12a2dc2e982
--- /dev/null
+++ b/drivers/misc/pvpanic/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Pvpanic Makefile
+#
+# Copyright (C) 2021 Oracle.
+#
+obj-$(CONFIG_PVPANIC_MMIO)	+= pvpanic.o pvpanic-mmio.o
diff --git a/drivers/misc/pvpanic.c b/drivers/misc/pvpanic/pvpanic-mmio.c
index f1655f5ca016..d7bf7db6c19c 100644
--- a/drivers/misc/pvpanic.c
+++ b/drivers/misc/pvpanic/pvpanic-mmio.c
@@ -1,13 +1,12 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- *  Pvpanic Device Support
+ *  Pvpanic MMIO Device Support
  *
  *  Copyright (C) 2013 Fujitsu.
  *  Copyright (C) 2018 ZTE.
+ *  Copyright (C) 2021 Oracle.
  */
 
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/kexec.h>
@@ -18,6 +17,12 @@
 
 #include <uapi/misc/pvpanic.h>
 
+#include "pvpanic.h"
+
+MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>");
+MODULE_DESCRIPTION("pvpanic-mmio device driver");
+MODULE_LICENSE("GPL");
+
 static void __iomem *base;
 static unsigned int capability = PVPANIC_PANICKED | PVPANIC_CRASH_LOADED;
 static unsigned int events;
@@ -49,47 +54,19 @@ static ssize_t events_store(struct device *dev,  struct device_attribute *attr,
 
 	events = tmp;
 
+	pvpanic_set_events(events);
+
 	return count;
 
 }
 static DEVICE_ATTR_RW(events);
 
-static struct attribute *pvpanic_dev_attrs[] = {
+static struct attribute *pvpanic_mmio_dev_attrs[] = {
 	&dev_attr_capability.attr,
 	&dev_attr_events.attr,
 	NULL
 };
-ATTRIBUTE_GROUPS(pvpanic_dev);
-
-MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>");
-MODULE_DESCRIPTION("pvpanic device driver");
-MODULE_LICENSE("GPL");
-
-static void
-pvpanic_send_event(unsigned int event)
-{
-	if (event & capability & events)
-		iowrite8(event, base);
-}
-
-static int
-pvpanic_panic_notify(struct notifier_block *nb, unsigned long code,
-		     void *unused)
-{
-	unsigned int event = PVPANIC_PANICKED;
-
-	if (kexec_crash_loaded())
-		event = PVPANIC_CRASH_LOADED;
-
-	pvpanic_send_event(event);
-
-	return NOTIFY_DONE;
-}
-
-static struct notifier_block pvpanic_panic_nb = {
-	.notifier_call = pvpanic_panic_notify,
-	.priority = 1, /* let this called before broken drm_fb_helper */
-};
+ATTRIBUTE_GROUPS(pvpanic_mmio_dev);
 
 static int pvpanic_mmio_probe(struct platform_device *pdev)
 {
@@ -119,9 +96,7 @@ static int pvpanic_mmio_probe(struct platform_device *pdev)
 	capability &= ioread8(base);
 	events = capability;
 
-	if (capability)
-		atomic_notifier_chain_register(&panic_notifier_list,
-					       &pvpanic_panic_nb);
+	pvpanic_probe(base, capability);
 
 	return 0;
 }
@@ -129,9 +104,7 @@ static int pvpanic_mmio_probe(struct platform_device *pdev)
 static int pvpanic_mmio_remove(struct platform_device *pdev)
 {
 
-	if (capability)
-		atomic_notifier_chain_unregister(&panic_notifier_list,
-						 &pvpanic_panic_nb);
+	pvpanic_remove();
 
 	return 0;
 }
@@ -153,7 +126,7 @@ static struct platform_driver pvpanic_mmio_driver = {
 		.name = "pvpanic-mmio",
 		.of_match_table = pvpanic_mmio_match,
 		.acpi_match_table = pvpanic_device_ids,
-		.dev_groups = pvpanic_dev_groups,
+		.dev_groups = pvpanic_mmio_dev_groups,
 	},
 	.probe = pvpanic_mmio_probe,
 	.remove = pvpanic_mmio_remove,
diff --git a/drivers/misc/pvpanic/pvpanic.c b/drivers/misc/pvpanic/pvpanic.c
new file mode 100644
index 000000000000..a9605f90c534
--- /dev/null
+++ b/drivers/misc/pvpanic/pvpanic.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  Pvpanic Device Support
+ *
+ *  Copyright (C) 2013 Fujitsu.
+ *  Copyright (C) 2018 ZTE.
+ *  Copyright (C) 2021 Oracle.
+ */
+
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+
+#include <uapi/misc/pvpanic.h>
+
+#include "pvpanic.h"
+
+MODULE_AUTHOR("Mihai Carabas <mihai.carabas@oracle.com>");
+MODULE_DESCRIPTION("pvpanic device driver ");
+MODULE_LICENSE("GPL");
+
+static void __iomem *base;
+static unsigned int capability;
+static unsigned int events;
+
+static void
+pvpanic_send_event(unsigned int event)
+{
+	if (event & capability & events)
+		iowrite8(event, base);
+}
+
+static int
+pvpanic_panic_notify(struct notifier_block *nb, unsigned long code,
+		     void *unused)
+{
+	unsigned int event = PVPANIC_PANICKED;
+
+	if (kexec_crash_loaded())
+		event = PVPANIC_CRASH_LOADED;
+
+	pvpanic_send_event(event);
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block pvpanic_panic_nb = {
+	.notifier_call = pvpanic_panic_notify,
+	.priority = 1, /* let this called before broken drm_fb_helper */
+};
+
+void pvpanic_probe(void __iomem *pbase, unsigned int dev_cap)
+{
+	base = pbase;
+	capability = dev_cap;
+	events = capability;
+
+	if (capability)
+		atomic_notifier_chain_register(&panic_notifier_list,
+					       &pvpanic_panic_nb);
+}
+EXPORT_SYMBOL_GPL(pvpanic_probe);
+
+void pvpanic_remove(void)
+{
+	if (capability)
+		atomic_notifier_chain_unregister(&panic_notifier_list,
+						 &pvpanic_panic_nb);
+	base = NULL;
+}
+EXPORT_SYMBOL_GPL(pvpanic_remove);
+
+void pvpanic_set_events(unsigned int dev_events)
+{
+	events = dev_events;
+}
+EXPORT_SYMBOL_GPL(pvpanic_set_events);
diff --git a/drivers/misc/pvpanic/pvpanic.h b/drivers/misc/pvpanic/pvpanic.h
new file mode 100644
index 000000000000..3abe15fa24b8
--- /dev/null
+++ b/drivers/misc/pvpanic/pvpanic.h
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  Pvpanic Device Support
+ *
+ *  Copyright (C) 2021 Oracle.
+ */
+
+#ifndef PVPANIC_H_
+#define PVPANIC_H_
+
+void pvpanic_probe(void __iomem *base, unsigned int dev_cap);
+void pvpanic_remove(void);
+void pvpanic_set_events(unsigned int dev_events);
+
+#endif /* PVPANIC_H_ */