[PATCH AUTOSEL 6.3 10/19] media: cec: core: disable adapter in cec_devnode_unregister

From: Sasha Levin
Date: Thu Jun 15 2023 - 07:39:05 EST


From: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>

[ Upstream commit fe4526d99e2e06b08bb80316c3a596ea6a807b75 ]

Explicitly disable the CEC adapter in cec_devnode_unregister()

Usually this does not really do anything important, but for drivers
that use the CEC pin framework this is needed to properly stop the
hrtimer. Without this a crash would happen when such a driver is
unloaded with rmmod.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/media/cec/core/cec-adap.c | 5 ++++-
drivers/media/cec/core/cec-core.c | 2 ++
drivers/media/cec/core/cec-priv.h | 1 +
3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/media/cec/core/cec-adap.c b/drivers/media/cec/core/cec-adap.c
index 4f5ab3cae8a71..ac18707fddcd2 100644
--- a/drivers/media/cec/core/cec-adap.c
+++ b/drivers/media/cec/core/cec-adap.c
@@ -1582,7 +1582,7 @@ static void cec_claim_log_addrs(struct cec_adapter *adap, bool block)
*
* This function is called with adap->lock held.
*/
-static int cec_adap_enable(struct cec_adapter *adap)
+int cec_adap_enable(struct cec_adapter *adap)
{
bool enable;
int ret = 0;
@@ -1592,6 +1592,9 @@ static int cec_adap_enable(struct cec_adapter *adap)
if (adap->needs_hpd)
enable = enable && adap->phys_addr != CEC_PHYS_ADDR_INVALID;

+ if (adap->devnode.unregistered)
+ enable = false;
+
if (enable == adap->is_enabled)
return 0;

diff --git a/drivers/media/cec/core/cec-core.c b/drivers/media/cec/core/cec-core.c
index af358e901b5f3..7e153c5cad04f 100644
--- a/drivers/media/cec/core/cec-core.c
+++ b/drivers/media/cec/core/cec-core.c
@@ -191,6 +191,8 @@ static void cec_devnode_unregister(struct cec_adapter *adap)
mutex_lock(&adap->lock);
__cec_s_phys_addr(adap, CEC_PHYS_ADDR_INVALID, false);
__cec_s_log_addrs(adap, NULL, false);
+ // Disable the adapter (since adap->devnode.unregistered is true)
+ cec_adap_enable(adap);
mutex_unlock(&adap->lock);

cdev_device_del(&devnode->cdev, &devnode->dev);
diff --git a/drivers/media/cec/core/cec-priv.h b/drivers/media/cec/core/cec-priv.h
index b78df931aa74b..ed1f8c67626bf 100644
--- a/drivers/media/cec/core/cec-priv.h
+++ b/drivers/media/cec/core/cec-priv.h
@@ -47,6 +47,7 @@ int cec_monitor_pin_cnt_inc(struct cec_adapter *adap);
void cec_monitor_pin_cnt_dec(struct cec_adapter *adap);
int cec_adap_status(struct seq_file *file, void *priv);
int cec_thread_func(void *_adap);
+int cec_adap_enable(struct cec_adapter *adap);
void __cec_s_phys_addr(struct cec_adapter *adap, u16 phys_addr, bool block);
int __cec_s_log_addrs(struct cec_adapter *adap,
struct cec_log_addrs *log_addrs, bool block);
--
2.39.2