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From 59267fc34f4900dcd2ec3295f6be04b79aee2186 Mon Sep 17 00:00:00 2001
From: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Date: Fri, 6 May 2022 09:43:25 +0200
Subject: [PATCH] media: cec-adap.c: fix is_configuring state
Git-commit: 59267fc34f4900dcd2ec3295f6be04b79aee2186
Patch-mainline: v5.19-rc1
References: git-fixes

If an adapter is trying to claim a free logical address then it is
in the 'is_configuring' state. If during that process the cable is
disconnected (HPD goes low, which in turn invalidates the physical
address), then cec_adap_unconfigure() is called, and that set the
is_configuring boolean to false, even though the thread that's
trying to claim an LA is still running.

Don't touch the is_configuring bool in cec_adap_unconfigure(), it
will eventually be cleared by the thread. By making that change
the cec_config_log_addr() function also had to change: it was
aborting if is_configuring became false (since that is what
cec_adap_unconfigure() did), but that no longer works. Instead
check if the physical address is invalid. That is a much
more appropriate check anyway.

This fixes a bug where the the adapter could be disabled even
though the device was still configuring. This could cause POLL
transmits to time out.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/media/cec/core/cec-adap.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/media/cec/core/cec-adap.c
+++ b/drivers/media/cec/core/cec-adap.c
@@ -1272,7 +1272,7 @@ static int cec_config_log_addr(struct ce
 		 * While trying to poll the physical address was reset
 		 * and the adapter was unconfigured, so bail out.
 		 */
-		if (!adap->is_configuring)
+		if (adap->phys_addr == CEC_PHYS_ADDR_INVALID)
 			return -EINTR;
 
 		if (err)
@@ -1329,7 +1329,6 @@ static void cec_adap_unconfigure(struct
 	    adap->phys_addr != CEC_PHYS_ADDR_INVALID)
 		WARN_ON(adap->ops->adap_log_addr(adap, CEC_LOG_ADDR_INVALID));
 	adap->log_addrs.log_addr_mask = 0;
-	adap->is_configuring = false;
 	adap->is_configured = false;
 	cec_flush(adap);
 	wake_up_interruptible(&adap->kthread_waitq);
@@ -1521,9 +1520,10 @@ unconfigure:
 	for (i = 0; i < las->num_log_addrs; i++)
 		las->log_addr[i] = CEC_LOG_ADDR_INVALID;
 	cec_adap_unconfigure(adap);
+	adap->is_configuring = false;
 	adap->kthread_config = NULL;
-	mutex_unlock(&adap->lock);
 	complete(&adap->config_completion);
+	mutex_unlock(&adap->lock);
 	return 0;
 }