[PATCH] ath10k: Introduce a devicetree quirk to skip host cap QMI requests

[Amit Pundir]

There are firmware versions which do not support host capability
QMI request. We suspect either the host cap is not implemented or
there may be firmware specific issues, but apparently there seem
to be a generation of firmware that has this particular behavior.

For example, firmware build on Xiaomi Poco F1 (sdm845) phone:
"QC_IMAGE_VERSION_STRING=WLAN.HL.2.0.c3-00257-QCAHLSWMTPLZ-1"

If we do not skip the host cap QMI request on Poco F1, then we
get a QMI_ERR_MALFORMED_MSG_V01 error message in the
ath10k_qmi_host_cap_send_sync(). But this error message is not
fatal to the firmware nor to the ath10k driver and we can still
bring up the WiFi services successfully if we just ignore it.

Hence introducing this DeviceTree quirk to skip host capability
QMI request for the firmware versions which do not support this
feature.

Suggested-by: Bjorn Andersson <bjorn.andersson at linaro.org>
Signed-off-by: Amit Pundir <amit.pundir at linaro.org>
---
 .../devicetree/bindings/net/wireless/qcom,ath10k.txt        |  5 +++++
 drivers/net/wireless/ath/ath10k/qmi.c                       | 13 ++++++++++---
 drivers/net/wireless/ath/ath10k/snoc.c                      |  3 +++
 drivers/net/wireless/ath/ath10k/snoc.h                      |  1 +
 4 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/wireless/qcom,ath10k.txt b/Documentation/devicetree/bindings/net/wireless/qcom,ath10k.txt
index 65ee68efd574..135c7ecd4487 100644
--- a/Documentation/devicetree/bindings/net/wireless/qcom,ath10k.txt
+++ b/Documentation/devicetree/bindings/net/wireless/qcom,ath10k.txt
@@ -86,6 +86,11 @@ Optional properties:
 	Value type: <empty>
 	Definition: Quirk specifying that the firmware expects the 8bit version
 		    of the host capability QMI request
+- qcom,snoc-host-cap-skip-quirk:
+	Usage: Optional
+	Value type: <empty>
+	Definition: Quirk specifying that the firmware wants to skip the host
+		    capability QMI request
 - qcom,xo-cal-data: xo cal offset to be configured in xo trim register.
 
 - qcom,msa-fixed-perm: Boolean context flag to disable SCM call for statically
diff --git a/drivers/net/wireless/ath/ath10k/qmi.c b/drivers/net/wireless/ath/ath10k/qmi.c
index 5468a41e928e..5adff7695e18 100644
--- a/drivers/net/wireless/ath/ath10k/qmi.c
+++ b/drivers/net/wireless/ath/ath10k/qmi.c
@@ -770,6 +770,7 @@ ath10k_qmi_ind_register_send_sync_msg(struct ath10k_qmi *qmi)
 static void ath10k_qmi_event_server_arrive(struct ath10k_qmi *qmi)
 {
 	struct ath10k *ar = qmi->ar;
+	struct ath10k_snoc *ar_snoc = ath10k_snoc_priv(ar);
 	int ret;
 
 	ret = ath10k_qmi_ind_register_send_sync_msg(qmi);
@@ -781,9 +782,15 @@ static void ath10k_qmi_event_server_arrive(struct ath10k_qmi *qmi)
 		return;
 	}
 
-	ret = ath10k_qmi_host_cap_send_sync(qmi);
-	if (ret)
-		return;
+	/*
+	 * Skip the host capability request for the firmware versions which
+	 * do not support this feature.
+	 */
+	if (!test_bit(ATH10K_SNOC_FLAG_SKIP_HOST_CAP_QUIRK, &ar_snoc->flags)) {
+		ret = ath10k_qmi_host_cap_send_sync(qmi);
+		if (ret)
+			return;
+	}
 
 	ret = ath10k_qmi_msa_mem_info_send_sync_msg(qmi);
 	if (ret)
diff --git a/drivers/net/wireless/ath/ath10k/snoc.c b/drivers/net/wireless/ath/ath10k/snoc.c
index 354d49b1cd45..4efbf1339c80 100644
--- a/drivers/net/wireless/ath/ath10k/snoc.c
+++ b/drivers/net/wireless/ath/ath10k/snoc.c
@@ -1281,6 +1281,9 @@ static void ath10k_snoc_quirks_init(struct ath10k *ar)
 
 	if (of_property_read_bool(dev->of_node, "qcom,snoc-host-cap-8bit-quirk"))
 		set_bit(ATH10K_SNOC_FLAG_8BIT_HOST_CAP_QUIRK, &ar_snoc->flags);
+
+	if (of_property_read_bool(dev->of_node, "qcom,snoc-host-cap-skip-quirk"))
+		set_bit(ATH10K_SNOC_FLAG_SKIP_HOST_CAP_QUIRK, &ar_snoc->flags);
 }
 
 int ath10k_snoc_fw_indication(struct ath10k *ar, u64 type)
diff --git a/drivers/net/wireless/ath/ath10k/snoc.h b/drivers/net/wireless/ath/ath10k/snoc.h
index a3dd06f6ac62..2a0045f0af7e 100644
--- a/drivers/net/wireless/ath/ath10k/snoc.h
+++ b/drivers/net/wireless/ath/ath10k/snoc.h
@@ -47,6 +47,7 @@ enum ath10k_snoc_flags {
 	ATH10K_SNOC_FLAG_UNREGISTERING,
 	ATH10K_SNOC_FLAG_RECOVERY,
 	ATH10K_SNOC_FLAG_8BIT_HOST_CAP_QUIRK,
+	ATH10K_SNOC_FLAG_SKIP_HOST_CAP_QUIRK,
 };
 
 struct clk_bulk_data;
-- 
2.7.4