WAR to handle WCN6750 hardware issue

[PATCH v1 0/3] WAR to handle WCN6750 hardware issue

Posted by Balakrishna Godavarthi 4 years ago

On WCN6750 sometimes observed AON power source takes 100ms
time to fully discharge voltage during OFF. As WCN6750 is
combo chip for WLAN and BT. If any of the tech area ON is
triggered during discharge phase, it fails to turn ON.
To overcome this hardware issue, During BT ON, driver check
for WLAN_EN pin status. If it high, it will pull BT_EN to high
immediately else it will wait for 100ms assuming WLAN was just
powered OFF and then BT_EN will be pulled to high.

Balakrishna Godavarthi (3):
  dt-bindings: net: bluetooth: Add wlan-gpio entry for wcn6750
  arm64: dts: qcom: sc7280: Add wlan enable gpio to bluetooth node
  Bluetooth: hci_qca: WAR to handle WCN6750 HW issue

 .../bindings/net/qualcomm-bluetooth.yaml           |  6 +++++
 arch/arm64/boot/dts/qcom/sc7280-idp.dtsi           |  1 +
 drivers/bluetooth/hci_qca.c                        | 30 +++++++++++++++++-----
 3 files changed, 31 insertions(+), 6 deletions(-)

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH v1 0/3] WAR to handle WCN6750 hardware issue

Posted by Dmitry Baryshkov 3 years, 10 months ago

On 29/04/2022 13:27, Balakrishna Godavarthi wrote:
> On WCN6750 sometimes observed AON power source takes 100ms
> time to fully discharge voltage during OFF. As WCN6750 is
> combo chip for WLAN and BT. If any of the tech area ON is
> triggered during discharge phase, it fails to turn ON.
> To overcome this hardware issue, During BT ON, driver check
> for WLAN_EN pin status. If it high, it will pull BT_EN to high
> immediately else it will wait for 100ms assuming WLAN was just
> powered OFF and then BT_EN will be pulled to high.

Ugh. This adds another point to support separate power sequencer device 
for WiFi+BT devices. Let me refresh my last patchset, so that we can 
implement it as a part of common code, rather than hacking hci_qca on 
and on.

> 
> Balakrishna Godavarthi (3):
>    dt-bindings: net: bluetooth: Add wlan-gpio entry for wcn6750
>    arm64: dts: qcom: sc7280: Add wlan enable gpio to bluetooth node
>    Bluetooth: hci_qca: WAR to handle WCN6750 HW issue
> 
>   .../bindings/net/qualcomm-bluetooth.yaml           |  6 +++++
>   arch/arm64/boot/dts/qcom/sc7280-idp.dtsi           |  1 +
>   drivers/bluetooth/hci_qca.c                        | 30 +++++++++++++++++-----
>   3 files changed, 31 insertions(+), 6 deletions(-)
> 


-- 
With best wishes
Dmitry