Re: [PATCH v3 1/1] Bluetooth: btqca: Add WCN6855 firmware priority selection feature

[Shuai Zhang]

Hi Dmitry

On 12/21/2025 11:21 PM, Dmitry Baryshkov wrote:
> On Fri, Dec 19, 2025 at 05:19:30PM +0800, Shuai Zhang wrote:
> > Hi Dmitry
> >
> > On 11/19/2025 3:59 PM, Dmitry Baryshkov wrote:
> > > On Mon, Nov 17, 2025 at 10:16:45AM +0800, Shuai Zhang wrote:
> > > > Historically, WCN685x and QCA2066 shared the same firmware files.
> > > > Now, changes are planned for the firmware that will make it incompatible
> > > > with QCA2066, so a new firmware name is required for WCN685x.
> > > >
> > > > Test Steps:
> > > >    - Boot device
> > > >    - Check the BTFW loading status via dmesg
> > > >
> > > > Sanity pass and Test Log:
> > > > QCA Downloading qca/wcnhpbftfw21.tlv
> > > > Direct firmware load for qca/wcnhpbftfw21.tlv failed with error -2
> > > > QCA Downloading qca/hpbftfw21.tlv
> > > >
> > > > Signed-off-by: Shuai Zhang<shuai.zhang@xxxxxxxxxxxxxxxx>
> > > > ---
> > > >    drivers/bluetooth/btqca.c | 22 ++++++++++++++++++++--
> > > >    1 file changed, 20 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/bluetooth/btqca.c b/drivers/bluetooth/btqca.c
> > > > index 7c958d606..8e0004ef7 100644
> > > > --- a/drivers/bluetooth/btqca.c
> > > > +++ b/drivers/bluetooth/btqca.c
> > > > @@ -847,8 +847,12 @@ int qca_uart_setup(struct hci_dev *hdev, uint8_t baudrate,
> > > >    				 "qca/msbtfw%02x.mbn", rom_ver);
> > > >    			break;
> > > >    		case QCA_WCN6855:
> > > > +			/* Due to historical reasons, WCN685x chip has been using firmware
> > > > +			 * without the "wcn" prefix. The mapping between the chip and its
> > > > +			 * corresponding firmware has now been corrected.
> > > > +			 */
> > > >    			snprintf(config.fwname, sizeof(config.fwname),
> > > > -				 "qca/hpbtfw%02x.tlv", rom_ver);
> > > > +				 "qca/wcnhpbtfw%02x.tlv", rom_ver);
> > > >    			break;
> > > >    		case QCA_WCN7850:
> > > >    			snprintf(config.fwname, sizeof(config.fwname),
> > > > @@ -861,6 +865,13 @@ int qca_uart_setup(struct hci_dev *hdev, uint8_t baudrate,
> > > >    	}
> > > >    	err = qca_download_firmware(hdev, &config, soc_type, rom_ver);
> > > > +
> > > > +	if (!rampatch_name && err < 0 && soc_type == QCA_WCN6855) {
> > > > +		snprintf(config.fwname, sizeof(config.fwname),
> > > > +			 "qca/hpbtfw%02x.tlv", rom_ver);
> > > > +		err = qca_download_firmware(hdev, &config, soc_type, rom_ver);
> > > > +	}
> > > Is there a reason for ignoring how it was done already for other cases when
> > > we need a similar fallback? Please extend the existing code (or rewrite
> > > it) instead of adding a similar hook at a completely different place.
> > Current Strategy (when DTS does not specify rampatch and firmware):
> >      Rampatch: Load the rampatch based on soc_type.
> >      NVM:  Load the NVM with board_id based on soc_type.
> >                  If the file corresponding to board_id does not exist, then
> > load the NVM file ending with .bin.
> >      For HSP (new requirement):
> >          First, load the rampatch/NVM files wcnhpbtfw and wcnhpnv.
> >          If not found:
> >          Rampatch: Fall back to loading the hpbtfw rampatch file.
> >          NVM:  Starting from wcnhpnv.bxxx, load the NVM file ending with
> > .bin.
> >                      If still not found, look for hpnv.bxxx and then apply
> > the above NVM strategy again (soc_type(board_id)  to .bin).
> >
> > The current changes are based on the original implementation, which should
> > make them the clearest modifications.
> > Please review according to the existing strategy, and feel free to let me
> > know if you have any questions.
> qca_download_firmware() has workaround code for WCN6750, loading TLV
> file if MBN is not present. It doesn't make sense to have similar
> workardounds in two different places. Could you please unify code
> (either by moving existing code or by moving your workaround).
I tried to move the changes into |qca_download_firmware|, but it 
conflicts with the logic for
loading the default NVM. Specifically, when there is no NVM 
corresponding to the board_id,
it will not load the |.bin| NVM file. I’m not sure whether this 
limitation is within a controllable range.

https://github.com/shuaz-shuai/Add-WCN6855-firmware-priority-selection-feature

> > > > +
> > > >    	if (err < 0) {
> > > >    		bt_dev_err(hdev, "QCA Failed to download patch (%d)", err);
> > > >    		return err;
> > > > @@ -923,7 +934,7 @@ int qca_uart_setup(struct hci_dev *hdev, uint8_t baudrate,
> > > >    		case QCA_WCN6855:
> > > >    			qca_read_fw_board_id(hdev, &boardid);
> > > >    			qca_get_nvm_name_by_board(config.fwname, sizeof(config.fwname),
> > > > -						  "hpnv", soc_type, ver, rom_ver, boardid);
> > > > +						  "wcnhpnv", soc_type, ver, rom_ver, boardid);
> > > >    			break;
> > > >    		case QCA_WCN7850:
> > > >    			qca_get_nvm_name_by_board(config.fwname, sizeof(config.fwname),
> > > > @@ -936,6 +947,13 @@ int qca_uart_setup(struct hci_dev *hdev, uint8_t baudrate,
> > > >    	}
> > > >    	err = qca_download_firmware(hdev, &config, soc_type, rom_ver);
> > > > +
> > > > +	if (!firmware_name && err < 0 && soc_type == QCA_WCN6855) {
> > > > +		qca_get_nvm_name_by_board(config.fwname, sizeof(config.fwname),
> > > > +					  "hpnv", soc_type, ver, rom_ver, boardid);
> > > > +		err = qca_download_firmware(hdev, &config, soc_type, rom_ver);
> > > > +	}
> > > > +
> > > >    	if (err < 0) {
> > > >    		bt_dev_err(hdev, "QCA Failed to download NVM (%d)", err);
> > > >    		return err;
> > > > --
> > > > 2.34.1
> > Thanks,
> > Shuai