PM / yenta: Split resume into early and late parts (rev. 4)

Commit 0c570cdeb8fdfcb354a3e9cd81bfc6a09c19de0c
(PM / yenta: Fix cardbus suspend/resume regression) caused resume to
fail on systems with two CardBus bridges.  While the exact nature
of the failure is not known at the moment, it can be worked around by
splitting the yenta resume into an early part, executed during the
early phase of resume, that will only resume the socket and power it
up if there was a card in it during suspend, and a late part,
executed during "regular" resume, that will carry out all of the
remaining yenta resume operations.

Fixes http://bugzilla.kernel.org/show_bug.cgi?id=14334, which is a
listed regression from 2.6.31.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reported-by: Stephen J. Gowdy <gowdy@cern.ch>
Tested-by: Jose Marino <braket@hotmail.com>

1 files changed, 43 insertions, 26 deletions

diff --git a/drivers/pcmcia/cs.c b/drivers/pcmcia/cs.c
index 934d4bee39a0..698d75cda084 100644
--- a/drivers/pcmcia/cs.c
+++ b/drivers/pcmcia/cs.c
@@ -98,10 +98,13 @@ EXPORT_SYMBOL(pcmcia_socket_list_rwsem);
  * These functions check for the appropriate struct pcmcia_soket arrays,
  * and pass them to the low-level functions pcmcia_{suspend,resume}_socket
  */
+static int socket_early_resume(struct pcmcia_socket *skt);
+static int socket_late_resume(struct pcmcia_socket *skt);
 static int socket_resume(struct pcmcia_socket *skt);
 static int socket_suspend(struct pcmcia_socket *skt);
 
-int pcmcia_socket_dev_suspend(struct device *dev)
+static void pcmcia_socket_dev_run(struct device *dev,
+                                  int (*cb)(struct pcmcia_socket *))
 {
         struct pcmcia_socket *socket;
 
@@ -110,29 +113,34 @@ int pcmcia_socket_dev_suspend(struct device *dev)
                 if (socket->dev.parent != dev)
                         continue;
                 mutex_lock(&socket->skt_mutex);
-                socket_suspend(socket);
+                cb(socket);
                 mutex_unlock(&socket->skt_mutex);
         }
         up_read(&pcmcia_socket_list_rwsem);
+}
 
+int pcmcia_socket_dev_suspend(struct device *dev)
+{
+        pcmcia_socket_dev_run(dev, socket_suspend);
         return 0;
 }
 EXPORT_SYMBOL(pcmcia_socket_dev_suspend);
 
-int pcmcia_socket_dev_resume(struct device *dev)
+void pcmcia_socket_dev_early_resume(struct device *dev)
 {
-        struct pcmcia_socket *socket;
+        pcmcia_socket_dev_run(dev, socket_early_resume);
+}
+EXPORT_SYMBOL(pcmcia_socket_dev_early_resume);
 
-        down_read(&pcmcia_socket_list_rwsem);
-        list_for_each_entry(socket, &pcmcia_socket_list, socket_list) {
-                if (socket->dev.parent != dev)
-                        continue;
-                mutex_lock(&socket->skt_mutex);
-                socket_resume(socket);
-                mutex_unlock(&socket->skt_mutex);
-        }
-        up_read(&pcmcia_socket_list_rwsem);
+void pcmcia_socket_dev_late_resume(struct device *dev)
+{
+        pcmcia_socket_dev_run(dev, socket_late_resume);
+}
+EXPORT_SYMBOL(pcmcia_socket_dev_late_resume);
 
+int pcmcia_socket_dev_resume(struct device *dev)
+{
+        pcmcia_socket_dev_run(dev, socket_resume);
         return 0;
 }
 EXPORT_SYMBOL(pcmcia_socket_dev_resume);
@@ -546,29 +554,24 @@ static int socket_suspend(struct pcmcia_socket *skt)
         return 0;
 }
 
-/*
- * Resume a socket.  If a card is present, verify its CIS against
- * our cached copy.  If they are different, the card has been
- * replaced, and we need to tell the drivers.
- */
-static int socket_resume(struct pcmcia_socket *skt)
+static int socket_early_resume(struct pcmcia_socket *skt)
 {
-        int ret;
-
-        if (!(skt->state & SOCKET_SUSPEND))
-                return -EBUSY;
-
         skt->socket = dead_socket;
         skt->ops->init(skt);
         skt->ops->set_socket(skt, &skt->socket);
+        if (skt->state & SOCKET_PRESENT)
+                skt->resume_status = socket_setup(skt, resume_delay);
+        return 0;
+}
 
+static int socket_late_resume(struct pcmcia_socket *skt)
+{
         if (!(skt->state & SOCKET_PRESENT)) {
                 skt->state &= ~SOCKET_SUSPEND;
                 return socket_insert(skt);
         }
 
-        ret = socket_setup(skt, resume_delay);
-        if (ret == 0) {
+        if (skt->resume_status == 0) {
                 /*
                  * FIXME: need a better check here for cardbus cards.
                  */
@@ -596,6 +599,20 @@ static int socket_resume(struct pcmcia_socket *skt)
         return 0;
 }
 
+/*
+ * Resume a socket.  If a card is present, verify its CIS against
+ * our cached copy.  If they are different, the card has been
+ * replaced, and we need to tell the drivers.
+ */
+static int socket_resume(struct pcmcia_socket *skt)
+{
+        if (!(skt->state & SOCKET_SUSPEND))
+                return -EBUSY;
+
+        socket_early_resume(skt);
+        return socket_late_resume(skt);
+}
+
 static void socket_remove(struct pcmcia_socket *skt)
 {
         dev_printk(KERN_NOTICE, &skt->dev,