Re: [PATCH v5] Bluetooth: btusb: Add support using different nvm for variant WCN6855 controller

[Matthias Kaehlcke <mka@chromium.org>]

On Tue, Aug 24, 2021 at 04:28:03PM +0800, Zijun Hu wrote:
> From: Tim Jiang <tjiang@codeaurora.org>
> 
> we have variant wcn6855 soc chip from different foundries, so we should
> use different nvm file with suffix to distinguish them.

Similar question as on v4: why is it necessary to know where a chip was
manufactured? Is the hardware different? Should the FW behave differently
for some reason (e.g. regulatory differences)?

> 
> Signed-off-by: Tim Jiang <tjiang@codeaurora.org>
> ---
>  drivers/bluetooth/btusb.c | 57 +++++++++++++++++++++++++++++++++++++----------
>  1 file changed, 45 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> index 60d2fce59a71..ad7734f8917c 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -3141,6 +3141,9 @@ 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;
> @@ -3172,6 +3175,7 @@ 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,
> @@ -3326,27 +3330,56 @@ static int btusb_setup_qca_load_rampatch(struct hci_dev *hdev,
>  	return err;
>  }
>  
> -static int btusb_setup_qca_load_nvm(struct hci_dev *hdev,
> -				    struct qca_version *ver,
> -				    const struct qca_device_info *info)
> +static void btusb_generate_qca_nvm_name(char **fwname,
> +					int max_size,
> +					struct qca_version *ver,
> +					char *foundry)
>  {
> -	const struct firmware *fw;
> -	char fwname[64];
> -	int err;
> +	char *separator;
> +	u16 board_id;
> +	u32 rom_version;
> +
> +	separator = (foundry == NULL) ? "" : "_";
> +	board_id = le16_to_cpu(ver->board_id);
> +	rom_version = le32_to_cpu(ver->rom_version);

Make the above assignments in the declaration.

>  
>  	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));
> +			snprintf(fwname, sizeof(fwname), "qca/nvm_usb_%08x%s%s.bin",
> +				 rom_version,
> +				 separator,
> +				 foundry);

the last three parameters could be in a single line.

>  		} else {
> -			snprintf(fwname, sizeof(fwname), "qca/nvm_usb_%08x_%04x.bin",
> -				le32_to_cpu(ver->rom_version),
> -				le16_to_cpu(ver->board_id));
> +			snprintf(fwname, sizeof(fwname), "qca/nvm_usb_%08x%s%s%04x.bin",
> +				rom_version,
> +				separator,
> +				foundry,
> +				board_id);

the last four parameters could be in a single line.

Besides the minor comments above this looks good to me in terms of code, but
I'd like to have a better understanding of why the origin of the chip is
important.