PM: Introduce library for device-specific OPPs (v7)

[mirror_ubuntu-artful-kernel.git] / drivers / base / power / trace.c

diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c
index 0a1a2c4dbc6e75e5647117b97ae1f055c2fdb080..9f4258df4cfdbace7c80d889154738f17c7d8461 100644 (file)
--- a/drivers/base/power/trace.c
+++ b/drivers/base/power/trace.c
@@ -188,8 +188,10 @@ static int show_file_hash(unsigned int value)
 static int show_dev_hash(unsigned int value)
 {
        int match = 0;
-       struct list_head *entry = dpm_list.prev;
+       struct list_head *entry;
 
+       device_pm_lock();
+       entry = dpm_list.prev;
        while (entry != &dpm_list) {
                struct device * dev = to_device(entry);
                unsigned int hash = hash_string(DEVSEED, dev_name(dev), DEVHASH);
@@ -199,11 +201,43 @@ static int show_dev_hash(unsigned int value)
                }
                entry = entry->prev;
        }
+       device_pm_unlock();
        return match;
 }
 
 static unsigned int hash_value_early_read;
 
+int show_trace_dev_match(char *buf, size_t size)
+{
+       unsigned int value = hash_value_early_read / (USERHASH * FILEHASH);
+       int ret = 0;
+       struct list_head *entry;
+
+       /*
+        * It's possible that multiple devices will match the hash and we can't
+        * tell which is the culprit, so it's best to output them all.
+        */
+       device_pm_lock();
+       entry = dpm_list.prev;
+       while (size && entry != &dpm_list) {
+               struct device *dev = to_device(entry);
+               unsigned int hash = hash_string(DEVSEED, dev_name(dev),
+                                               DEVHASH);
+               if (hash == value) {
+                       int len = snprintf(buf, size, "%s\n",
+                                           dev_driver_string(dev));
+                       if (len > size)
+                               len = size;
+                       buf += len;
+                       ret += len;
+                       size -= len;
+               }
+               entry = entry->prev;
+       }
+       device_pm_unlock();
+       return ret;
+}
+
 static int early_resume_init(void)
 {
        hash_value_early_read = read_magic_time();