ipmi: Fix how the lower layers are told to watch for messages

[ Upstream commit c65ea996595005be470fbfa16711deba414fd33b ]

The IPMI driver has a mechanism to tell the lower layers it needs
to watch for messages, commands, and watchdogs (so it doesn't
needlessly poll).  However, it needed some extensions, it needed
a way to tell what is being waited for so it could set the timeout
appropriately.

The update to the lower layer was also being done once a second
at best because it was done in the main timeout handler.  However,
if a command is sent and a response message is coming back,
it needed to be started immediately.  So modify the code to
update immediately if it needs to be enabled.  Disable is still
lazy.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Tested-by: Kamlakant Patel <kamlakant.patel@cavium.com>
Stable-dep-of: 6d2555cde291 ("ipmi: fix SSIF not responding under certain cond.")
Signed-off-by: Sasha Levin <sashal@kernel.org>

1 files changed, 29 insertions, 7 deletions

diff --git a/include/linux/ipmi_smi.h b/include/linux/ipmi_smi.h
index 1995ce146789..86b119400f30 100644
--- a/include/linux/ipmi_smi.h
+++ b/include/linux/ipmi_smi.h
@@ -31,6 +31,17 @@ struct device;
 typedef struct ipmi_smi *ipmi_smi_t;
 
 /*
+ * Flags for set_check_watch() below.  Tells if the SMI should be
+ * waiting for watchdog timeouts, commands and/or messages.  There is
+ * also an internal flag for the message handler, SMIs should ignore
+ * it.
+ */
+#define IPMI_WATCH_MASK_INTERNAL	(1 << 0)
+#define IPMI_WATCH_MASK_CHECK_MESSAGES	(1 << 1)
+#define IPMI_WATCH_MASK_CHECK_WATCHDOG	(1 << 2)
+#define IPMI_WATCH_MASK_CHECK_COMMANDS	(1 << 3)
+
+/*
  * Messages to/from the lower layer.  The smi interface will take one
  * of these to send. After the send has occurred and a response has
  * been received, it will report this same data structure back up to
@@ -55,8 +66,16 @@ struct ipmi_smi_msg {
 	int           rsp_size;
 	unsigned char rsp[IPMI_MAX_MSG_LENGTH];
 
-	/* Will be called when the system is done with the message
-	   (presumably to free it). */
+	/*
+	 * There should be a response message coming back in the BMC
+	 * message queue.
+	 */
+	bool needs_response;
+
+	/*
+	 * Will be called when the system is done with the message
+	 * (presumably to free it).
+	 */
 	void (*done)(struct ipmi_smi_msg *msg);
 };
 
@@ -105,12 +124,15 @@ struct ipmi_smi_handlers {
 
 	/*
 	 * Called by the upper layer when some user requires that the
-	 * interface watch for events, received messages, watchdog
-	 * pretimeouts, or not.  Used by the SMI to know if it should
-	 * watch for these.  This may be NULL if the SMI does not
-	 * implement it.
+	 * interface watch for received messages and watchdog
+	 * pretimeouts (basically do a "Get Flags", or not.  Used by
+	 * the SMI to know if it should watch for these.  This may be
+	 * NULL if the SMI does not implement it.  watch_mask is from
+	 * IPMI_WATCH_MASK_xxx above.  The interface should run slower
+	 * timeouts for just watchdog checking or faster timeouts when
+	 * waiting for the message queue.
 	 */
-	void (*set_need_watch)(void *send_info, bool enable);
+	void (*set_need_watch)(void *send_info, unsigned int watch_mask);
 
 	/*
 	 * Called when flushing all pending messages.