Re: [PATCH] wifi: rtw88: usb: Simplify rtw_usb_write_data

[Bitterblue Smith <rtl8821cerfe2@gmail.com>]

On 03/05/2024 01:18, Larry Finger wrote:
> On 5/2/24 4:23 PM, Bitterblue Smith wrote:
>> The skb created in this function always has the same headroom,
>> the chip's TX descriptor size. Use chip->tx_pkt_desc_sz directly.
>>
>> Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
>> ---
>> This is the patch I promised earlier:
>> https://lore.kernel.org/linux-wireless/cae2d330-a4fb-4570-9dde-09684af23ffd@gmail.com/
>> ---
>>   drivers/net/wireless/realtek/rtw88/usb.c | 14 +++++---------
>>   1 file changed, 5 insertions(+), 9 deletions(-)
>>
>> diff --git a/usb.c b/usb.c
>> index 1dfe7c6ae4ba..ff57976b9d3b 100644
>> --- a/usb.c
>> +++ b/usb.c
>> @@ -440,23 +440,21 @@ static int rtw_usb_write_data(struct rtw_dev *rtwdev,
>>   {
>>       const struct rtw_chip_info *chip = rtwdev->chip;
>>       struct sk_buff *skb;
>> -    unsigned int desclen, headsize, size;
>> +    unsigned int size;
>>       u8 qsel;
>>       int ret = 0;
>>          size =pkt_info->tx_pkt_size;
>>       qsel = pkt_info->qsel;
>> -    desclen = chip->tx_pkt_desc_sz;
>> -    headsize = pkt_info->offset ? pkt_info->offset : desclen;
>>   -    skb = dev_alloc_skb(headsize + size);
>> +    skb = dev_alloc_skb(chip->tx_pkt_desc_sz + size);
>>       if (unlikely(!skb))
>>           return -ENOMEM;
>>   -    skb_reserve(skb, headsize);
>> +    skb_reserve(skb, chip->tx_pkt_desc_sz);
>>       skb_put_data(skb, buf, size);
>> -    skb_push(skb, headsize);
>> -    memset(skb->data, 0, headsize);
>> +    skb_push(skb, chip->tx_pkt_desc_sz);
>> +    memset(skb->data, 0, chip->tx_pkt_desc_sz);
>>       rtw_tx_fill_tx_desc(pkt_info, skb);
>>       rtw_tx_fill_txdesc_checksum(rtwdev, pkt_info, skb->data);
>>   @@ -471,12 +469,10 @@ static int rtw_usb_write_data(struct rtw_dev *rtwdev,
>>   static int rtw_usb_write_data_rsvd_page(struct rtw_dev *rtwdev, u8 *buf,
>>                       u32 size)
>>   {
>> -    const struct rtw_chip_info *chip = rtwdev->chip;
>>       struct rtw_tx_pkt_info pkt_info = {0};
>>         pkt_info.tx_pkt_size = size;
>>       pkt_info.qsel = TX_DESC_QSEL_BEACON;
>> -    pkt_info.offset = chip->tx_pkt_desc_sz;
>>         return rtw_usb_write_data(rtwdev, &pkt_info, buf);
>>   }
> 
> This patch doesn't work. When I add it and start an 8822bu, I get:
> 
> [   46.695755] usb 3-6: new high-speed USB device number 4 using xhci_hcd
> [   46.844397] usb 3-6: New USB device found, idVendor=0bda, idProduct=b82c, bcdDevice= 2.10
> [   46.844404] usb 3-6: New USB device strings: Mfr=1, Product=2, SerialNumber=3
> [   46.844406] usb 3-6: Product: 802.11ac NIC
> [   46.844408] usb 3-6: Manufacturer: Realtek
> [   46.844410] usb 3-6: SerialNumber: 123456
> [   47.524214] rtw_8822bu 3-6:1.2: Firmware version 27.2.0, H2C version 13
> [   47.573043] rtw_8822bu 3-6:1.2: error beacon valid
> [   47.573165] rtw_8822bu 3-6:1.2: failed to download rsvd page
> [   47.573488] rtw_8822bu 3-6:1.2: failed to download firmware
> [   47.576745] rtw_8822bu 3-6:1.2: failed to setup chip efuse info
> [   47.576750] rtw_8822bu 3-6:1.2: failed to setup chip information
> [   47.577302] rtw_8822bu 3-6:1.2: probe with driver rtw_8822bu failed with error -16
> 
> When I added code to test if chip->tx_pkt_desc_sz was equal to pkt_info->tx_pkt_size at entry, it reported that there was a difference.
> 
> This patch may work for some of the devices, but clearly not for all.
> 
> NACK.
> 
> Larry

Thank you for testing. Indeed, the second hunk is breaking
the firmware upload.