Re: [PATCH v2] Bluetooth: btusb: Add support for variant WCN6855 by using different nvm

[Matthias Kaehlcke <mka@chromium.org>]

On Tue, Oct 12, 2021 at 03:55:56PM +0800, tjiang@codeaurora.org wrote:
> the RF performance of wcn6855 soc chip from different foundries will be
> difference, so we should use different nvm to configure them.
> 
> Signed-off-by: Tim Jiang <tjiang@codeaurora.org>
> ---
>  drivers/bluetooth/btusb.c | 56
> +++++++++++++++++++++++++++++++++++------------
>  1 file changed, 42 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> index 75c83768c257..f352ff351b61 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -3190,6 +3190,9 @@ static int btusb_set_bdaddr_wcn6855(struct hci_dev
> *hdev,
>  #define QCA_DFU_TIMEOUT		3000
>  #define QCA_FLAG_MULTI_NVM      0x80
> 
> +#define WCN6855_2_0_RAM_VERSION_GF 0x400c1200
> +#define WCN6855_2_1_RAM_VERSION_GF 0x400c1211
> +
>  struct qca_version {
>  	__le32	rom_version;
>  	__le32	patch_version;
> @@ -3221,6 +3224,7 @@ static const struct qca_device_info
> qca_devices_table[] = {
>  	{ 0x00000302, 28, 4, 16 }, /* Rome 3.2 */
>  	{ 0x00130100, 40, 4, 16 }, /* WCN6855 1.0 */
>  	{ 0x00130200, 40, 4, 16 }, /* WCN6855 2.0 */
> +	{ 0x00130201, 40, 4, 16 }, /* WCN6855 2.1 */
>  };
> 
>  static int btusb_qca_send_vendor_req(struct usb_device *udev, u8 request,
> @@ -3375,6 +3379,43 @@ static int btusb_setup_qca_load_rampatch(struct
> hci_dev *hdev,
>  	return err;
>  }
> 
> +static void btusb_generate_qca_nvm_name(char *fwname,
> +					size_t max_size,
> +					struct qca_version *ver)

=> const struct qca_version *ver

> +{
> +	u32 rom_version = le32_to_cpu(ver->rom_version);
> +	u16 flag = le16_to_cpu(ver->flag);
> +
> +	if (((flag >> 8) & 0xff) == QCA_FLAG_MULTI_NVM) {
> +		u16 board_id = le16_to_cpu(ver->board_id);
> +		u32 ram_version = le32_to_cpu(ver->ram_version);
> +		const char *variant;
> +
> +		switch (ram_version) {
> +		case WCN6855_2_0_RAM_VERSION_GF:
> +		case WCN6855_2_1_RAM_VERSION_GF:
> +			variant = "_gf";
> +			break;
> +		default:
> +			variant = "";

instead of the default branch you could assign a default to 'variant' at
declaration time, but it's fine either way.

> +			break;
> +		}
> +
> +		/* if boardid equal 0, use default nvm without suffix */

delete the comment, it just states the obvious

> +		if (board_id == 0x0) {

nit: is there really any value in using a hex number here instead of a
plain decimal 0?

> +			snprintf(fwname, max_size, "qca/nvm_usb_%08x%s.bin",
> +				rom_version, variant);
> +		} else {
> +			snprintf(fwname, max_size, "qca/nvm_usb_%08x%s_%04x.bin",
> +				rom_version, variant, board_id);
> +		}
> +	} else {
> +		snprintf(fwname, max_size, "qca/nvm_usb_%08x.bin",
> +			rom_version);
> +	}
> +
> +}
> +
>  static int btusb_setup_qca_load_nvm(struct hci_dev *hdev,
>  				    struct qca_version *ver,
>  				    const struct qca_device_info *info)
> @@ -3383,20 +3424,7 @@ static int btusb_setup_qca_load_nvm(struct hci_dev
> *hdev,
>  	char fwname[64];
>  	int err;
> 
> -	if (((ver->flag >> 8) & 0xff) == QCA_FLAG_MULTI_NVM) {
> -		/* if boardid equal 0, use default nvm without surfix */
> -		if (le16_to_cpu(ver->board_id) == 0x0) {
> -			snprintf(fwname, sizeof(fwname), "qca/nvm_usb_%08x.bin",
> -				 le32_to_cpu(ver->rom_version));
> -		} else {
> -			snprintf(fwname, sizeof(fwname), "qca/nvm_usb_%08x_%04x.bin",
> -				le32_to_cpu(ver->rom_version),
> -				le16_to_cpu(ver->board_id));
> -		}
> -	} else {
> -		snprintf(fwname, sizeof(fwname), "qca/nvm_usb_%08x.bin",
> -			 le32_to_cpu(ver->rom_version));
> -	}
> +	btusb_generate_qca_nvm_name(fwname, sizeof(fwname), ver);
> 
>  	err = request_firmware(&fw, fwname, &hdev->dev);
>  	if (err) {