mwifiex: Add quirk to disable deep sleep with certain hardware revision

The 88W8897 PCIe+USB card in the hardware revision 20 apparently has a
hardware issue where the card wakes up from deep sleep randomly and very
often, somewhat depending on the card activity, maybe the hardware has a
floating wakeup pin or something. This was found by comparing two MS
Surface Book 2 devices, where one devices wifi card experienced spurious
wakeups, while the other one didn't.

Those continuous wakeups prevent the card from entering host sleep when
the computer suspends. And because the host won't answer to events from
the card anymore while it's suspended, the firmwares internal power
saving state machine seems to get confused and the card can't sleep
anymore at all after that.

Since we can't work around that hardware bug in the firmware, let's
get the hardware revision string from the firmware and match it with
known bad revisions. Then disable auto deep sleep for those revisions,
which makes sure we no longer get those spurious wakeups.

Signed-off-by: Jonas Dreßler <verdre@v0yd.nl>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20211103201800.13531-3-verdre@v0yd.nl

1 files changed, 18 insertions, 0 deletions

diff --git a/drivers/net/wireless/marvell/mwifiex/main.c b/drivers/net/wireless/marvell/mwifiex/main.c
index 19b996c6a260..ace7371c4773 100644
--- a/drivers/net/wireless/marvell/mwifiex/main.c
+++ b/drivers/net/wireless/marvell/mwifiex/main.c
@@ -226,6 +226,23 @@ exit_rx_proc:
 	return 0;
 }
 
+static void maybe_quirk_fw_disable_ds(struct mwifiex_adapter *adapter)
+{
+	struct mwifiex_private *priv = mwifiex_get_priv(adapter, MWIFIEX_BSS_ROLE_STA);
+	struct mwifiex_ver_ext ver_ext;
+
+	if (test_and_set_bit(MWIFIEX_IS_REQUESTING_FW_VEREXT, &adapter->work_flags))
+		return;
+
+	memset(&ver_ext, 0, sizeof(ver_ext));
+	ver_ext.version_str_sel = 1;
+	if (mwifiex_send_cmd(priv, HostCmd_CMD_VERSION_EXT,
+			     HostCmd_ACT_GEN_GET, 0, &ver_ext, false)) {
+		mwifiex_dbg(priv->adapter, MSG,
+			    "Checking hardware revision failed.\n");
+	}
+}
+
 /*
  * The main process.
  *
@@ -356,6 +373,7 @@ process_start:
 			if (adapter->hw_status == MWIFIEX_HW_STATUS_INIT_DONE) {
 				adapter->hw_status = MWIFIEX_HW_STATUS_READY;
 				mwifiex_init_fw_complete(adapter);
+				maybe_quirk_fw_disable_ds(adapter);
 			}
 		}