[PATCH V4 3/6] misc/pvpanic: add API for pvpanic driver framework

[Peng Hao]

Add pvpanic_add/remove_device API. Follow-up patches will use them to
add/remove specific drivers into framework.

Signed-off-by: Peng Hao <peng.h...@zte.com.cn>
---
 drivers/misc/pvpanic/pvpanic.c | 47 ++++++++++++++++++++++++++++++++++++++----
 drivers/misc/pvpanic/pvpanic.h | 15 ++++++++++++++
 2 files changed, 58 insertions(+), 4 deletions(-)
 create mode 100644 drivers/misc/pvpanic/pvpanic.h

diff --git a/drivers/misc/pvpanic/pvpanic.c b/drivers/misc/pvpanic/pvpanic.c
index f44a884..6225dfb 100644
--- a/drivers/misc/pvpanic/pvpanic.c
+++ b/drivers/misc/pvpanic/pvpanic.c
@@ -14,7 +14,11 @@
 #include <linux/platform_device.h>
 #include <linux/types.h>
 
-static void __iomem *base;
+static struct {
+       struct platform_device *pdev;
+       void __iomem *base;
+       bool is_ioport;
+} pvpanic_data;
 
 #define PVPANIC_PANICKED        (1 << 0)
 
@@ -25,7 +29,7 @@
 static void
 pvpanic_send_event(unsigned int event)
 {
-       iowrite8(event, base);
+       iowrite8(event, pvpanic_data.base);
 }
 
 static int
@@ -41,10 +45,43 @@
        .priority = 1, /* let this called before broken drm_fb_helper */
 };
 
+int pvpanic_add_device(struct device *dev, struct resource *res)
+{
+       struct platform_device *pdev;
+       int ret;
+
+       pdev = platform_device_alloc("pvpanic", -1);
+       if (!pdev)
+               return -ENOMEM;
+
+       pdev->dev.parent = dev;
+
+       ret = platform_device_add_resources(pdev, res, 1);
+       if (ret)
+               goto err;
+
+       ret = platform_device_add(pdev);
+       if (ret)
+               goto err;
+       pvpanic_data.pdev = pdev;
+
+       return 0;
+err:
+       platform_device_put(pdev);
+       return -1;
+}
+
+void pvpanic_remove_device(void)
+{
+       platform_device_unregister(pvpanic_data.pdev);
+       pvpanic_data.pdev = NULL;
+}
+
 static int pvpanic_platform_probe (struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
        struct resource *res;
+       void __iomem *base;
 
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (res) {
@@ -59,8 +96,10 @@ static int pvpanic_platform_probe (struct platform_device 
*pdev)
                base = ioport_map(res->start, resource_size(res));
                if (!base)
                        return -ENODEV;
+               pvpanic_data.is_ioport = true;
         }
 
+       pvpanic_data.base = base;
        atomic_notifier_chain_register(&panic_notifier_list,
                                       &pvpanic_panic_nb);
 
@@ -71,8 +110,8 @@ static int pvpanic_platform_remove(struct platform_device 
*pdev)
 {
        atomic_notifier_chain_unregister(&panic_notifier_list,
                                         &pvpanic_panic_nb);
-
-       iounmap(base);
+       if (pvpanic_data.is_ioport)
+               iounmap(pvpanic_data.base);
 
        return 0;
 }
diff --git a/drivers/misc/pvpanic/pvpanic.h b/drivers/misc/pvpanic/pvpanic.h
new file mode 100644
index 0000000..7fb6bb2
--- /dev/null
+++ b/drivers/misc/pvpanic/pvpanic.h
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* pvpanic driver framework header file
+ *
+ * Copyright (C) 2019 ZTE Ltd.
+ *
+ * Author: Peng Hao <peng.h...@zte.com.cn>
+ */
+
+#ifndef __DRIVERS_MISC_PVPANIC_H
+#define __DRIVERS_MISC_PVPANIC_H
+
+extern int pvpanic_add_device(struct device *dev, struct resource *res);
+extern void pvpanic_remove_device(void);
+
+#endif
-- 
1.8.3.1