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Date: Thu, 16 May 2024 07:57:41 +0200
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To: kiran.k@intel.com, Marcel Holtmann <marcel@holtmann.org>
Cc: linux-bluetooth@vger.kernel.org
From: Oliver Neukum <oneukum@suse.com>
Subject: question regarding ordering in btintel_pcie_send_sync()
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Hi,

I was looking at the code. I do not have documentation for the
device, but it looks relatively ordinary. Hence this piece of
code caught my eye:


         /* Set the doorbell to notify the device */
         btintel_pcie_set_tx_db(data, tfd_index);

Requesting an interrupt. However, are you sure the IO can be processed
and trigger an interrupt only after the PCI write, which this triggers?

         /* Wait for the complete interrupt - URBD0 */
         ret = wait_event_timeout(data->tx_wait_q, data->tx_wait_done,
                                  msecs_to_jiffies(BTINTEL_PCIE_TX_WAIT_TIMEOUT_MS));

	Regards
		Oliver