Bluetooth: btqca: Add a short delay before downloading the NVM

[ Upstream commit 8059ba0bd0e4694e51c2ee6438a77b325f06c0d5 ]

On WCN3990 downloading the NVM sometimes fails with a "TLV response
size mismatch" error:

[  174.949955] Bluetooth: btqca.c:qca_download_firmware() hci0: QCA Downloading qca/crnv21.bin
[  174.958718] Bluetooth: btqca.c:qca_tlv_send_segment() hci0: QCA TLV response size mismatch

It seems the controller needs a short time after downloading the
firmware before it is ready for the NVM. A delay as short as 1 ms
seems sufficient, make it 10 ms just in case. No event is received
during the delay, hence we don't just silently drop an extra event.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/bluetooth/btqca.c b/drivers/bluetooth/btqca.c
index ec9e03a..9e70f7c 100644 (file)
--- a/drivers/bluetooth/btqca.c
+++ b/drivers/bluetooth/btqca.c
@@ -363,6 +363,9 @@ int qca_uart_setup(struct hci_dev *hdev, uint8_t baudrate,
                return err;
        }
 
+       /* Give the controller some time to get ready to receive the NVM */
+       msleep(10);
+
        /* Download NVM configuration */
        config.type = TLV_TYPE_NVM;
        if (soc_type == QCA_WCN3990)