[PATCH] pm: print name of failed suspend function

Print more diagnostic info to help identify the source of power management
suspend failures.

Example:

usb_hcd_pci_suspend(): pci_set_power_state+0x0/0x1af() returns -22
pci_device_suspend(): usb_hcd_pci_suspend+0x0/0x11b() returns -22
suspend_device(): pci_device_suspend+0x0/0x34() returns -22

Work-in-progress.  It needs lots more suspend_report_result() calls sprinkled
everywhere.

Cc: Patrick Mochel <mochel@digitalimplant.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@suspend2.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/base/power/suspend.c b/drivers/base/power/suspend.c
index bdb60663f2ef..662209d3f42d 100644
--- a/drivers/base/power/suspend.c
+++ b/drivers/base/power/suspend.c
@@ -10,6 +10,8 @@
 
 #include <linux/vt_kern.h>
 #include <linux/device.h>
+#include <linux/kallsyms.h>
+#include <linux/pm.h>
 #include "../base.h"
 #include "power.h"
 
@@ -58,6 +60,7 @@ int suspend_device(struct device * dev, pm_message_t state)
         if (dev->bus && dev->bus->suspend && !dev->power.power_state.event) {
                 dev_dbg(dev, "suspending\n");
                 error = dev->bus->suspend(dev, state);
+                suspend_report_result(dev->bus->suspend, error);
         }
         up(&dev->sem);
         return error;
@@ -169,3 +172,12 @@ int device_power_down(pm_message_t state)
 
 EXPORT_SYMBOL_GPL(device_power_down);
 
+void __suspend_report_result(const char *function, void *fn, int ret)
+{
+        if (ret) {
+                printk(KERN_ERR "%s(): ", function);
+                print_fn_descriptor_symbol("%s() returns ", (unsigned long)fn);
+                printk("%d\n", ret);
+        }
+}
+EXPORT_SYMBOL_GPL(__suspend_report_result);