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From: Douglas Anderson <dianders@chromium.org>
To: Marcel Holtmann <marcel@holtmann.org>,
	Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Cc: Stephen Boyd <swboyd@chromium.org>,
	Guenter Roeck <groeck@chromium.org>,
	Johan Hovold <johan+linaro@kernel.org>,
	Bartosz Golaszewski <bartosz.golaszewski@linaro.org>,
	Douglas Anderson <dianders@chromium.org>,
	Sai Teja Aluvala <quic_saluvala@quicinc.com>,
	linux-bluetooth@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH] Bluetooth: qca: If memdump doesn't work, re-enable IBS
Date: Fri, 17 May 2024 17:02:46 -0700
Message-ID: <20240517170246.1.Ia769fe5fbeaa6aca2edfb01b82eb7df0c6955459@changeid>
Precedence: bulk
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On systems in the field, we are seeing this sometimes in the kernel logs:
  Bluetooth: qca_controller_memdump() hci0: hci_devcd_init Return:-95

This means that _something_ decided that it wanted to get a memdump
but then hci_devcd_init() returned -EOPNOTSUPP (AKA -95).

The cleanup code in qca_controller_memdump() when we get back an error
from hci_devcd_init() undoes most things but forgets to clear
QCA_IBS_DISABLED. One side effect of this is that, during the next
suspend, qca_suspend() will always get a timeout.

Let's fix it so that we clear the bit.

Fixes: 06d3fdfcdf5c ("Bluetooth: hci_qca: Add qcom devcoredump support")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
I'm nowhere near an expert on this code so please give extra eyes on
this patch. I also have no idea how to reproduce the problem nor even
how to trigger a memdump to test it. I'd love any advice that folks
could give. ;-)

 drivers/bluetooth/hci_qca.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index 0c9c9ee56592..1ef12f5a115d 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -1090,6 +1090,7 @@ static void qca_controller_memdump(struct work_struct *work)
 				qca->memdump_state = QCA_MEMDUMP_COLLECTED;
 				cancel_delayed_work(&qca->ctrl_memdump_timeout);
 				clear_bit(QCA_MEMDUMP_COLLECTION, &qca->flags);
+				clear_bit(QCA_IBS_DISABLED, &qca->flags);
 				mutex_unlock(&qca->hci_memdump_lock);
 				return;
 			}
-- 
2.45.0.rc1.225.g2a3ae87e7f-goog