On Fri, May 20, 2022 at 07:39:03AM +0000, Pkshih wrote: > On Wed, 2022-05-18 at 10:23 +0200, Sascha Hauer wrote: > > Add the common bits and pieces to add USB support to the RTW88 driver. > > This is based on https://github.com/ulli-kroll/rtw88-usb.git which > > itself is first written by Neo Jou. > > > > Signed-off-by: neo_jou <neo_jou@xxxxxxxxxxx> > > Signed-off-by: Hans Ulli Kroll <linux@xxxxxxxxxxxxx> > > Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> > > --- > > drivers/net/wireless/realtek/rtw88/Kconfig | 3 + > > drivers/net/wireless/realtek/rtw88/Makefile | 2 + > > drivers/net/wireless/realtek/rtw88/mac.c | 3 + > > drivers/net/wireless/realtek/rtw88/main.c | 5 + > > drivers/net/wireless/realtek/rtw88/main.h | 4 + > > drivers/net/wireless/realtek/rtw88/reg.h | 1 + > > drivers/net/wireless/realtek/rtw88/tx.h | 31 + > > drivers/net/wireless/realtek/rtw88/usb.c | 1051 +++++++++++++++++++ > > drivers/net/wireless/realtek/rtw88/usb.h | 109 ++ > > 9 files changed, 1209 insertions(+) > > create mode 100644 drivers/net/wireless/realtek/rtw88/usb.c > > create mode 100644 drivers/net/wireless/realtek/rtw88/usb.h > > > > [...] > > > diff --git a/drivers/net/wireless/realtek/rtw88/reg.h b/drivers/net/wireless/realtek/rtw88/reg.h > > index 84ba9ec489c37..a928899030863 100644 > > --- a/drivers/net/wireless/realtek/rtw88/reg.h > > +++ b/drivers/net/wireless/realtek/rtw88/reg.h > > @@ -184,6 +184,7 @@ > > #define BIT_TXDMA_VIQ_MAP(x) \ > ^^^^^^^ replace 8 spaces by one tab This line is not added by me. There are spaces used before the linebreaks throughout this file. > > + do { > > + spin_lock_irqsave(&rtwusb->rx_data_list_lock, flags); > > + > > + rxcb = list_first_entry_or_null(&rtwusb->rx_data_free, > > + struct rx_usb_ctrl_block, list); > > + > > + spin_unlock_irqrestore(&rtwusb->rx_data_list_lock, flags); > > + if (!rxcb) > > + return; > > + > > + rxcb->rx_skb = alloc_skb(RTW_USB_MAX_RECVBUF_SZ, GFP_KERNEL); > > + if (!rxcb->rx_skb) { > > + rtw_err(rtwdev, "could not allocate rx skbuff\n"); > > + return; > > + } > > + > > + usb_fill_bulk_urb(rxcb->rx_urb, rtwusb->udev, > > + usb_rcvbulkpipe(rtwusb->udev, rtwusb->pipe_in), > > + rxcb->rx_skb->data, RTW_USB_MAX_RECVBUF_SZ, > > + rtw_usb_read_port_complete, rxcb); > > + > > + spin_lock_irqsave(&rtwusb->rx_data_list_lock, flags); > > + list_move(&rxcb->list, &rtwusb->rx_data_used); > > + spin_unlock_irqrestore(&rtwusb->rx_data_list_lock, flags); > > + > > + error = usb_submit_urb(rxcb->rx_urb, GFP_KERNEL); > > + if (error) { > > + kfree_skb(rxcb->rx_skb); > > + if (error != -ENODEV) > > + rtw_err(rtwdev, "Err sending rx data urb %d\n", > > + error); > > + rtw_usb_rx_data_put(rtwusb, rxcb); > > + > > + return; > > + } > > + } while (true); > > Can we have a limit of 'for(;<limit;)' insetad of 'while (true)'? Not sure if it's worth it, but yes, it shouldn't hurt either. > > > +} > > + > > +static void rtw_usb_cancel_rx_bufs(struct rtw_usb *rtwusb) > > +{ > > + struct rx_usb_ctrl_block *rxcb; > > + unsigned long flags; > > + > > + spin_lock_irqsave(&rtwusb->rx_data_list_lock, flags); > > + > > + while (true) { > > + rxcb = list_first_entry_or_null(&rtwusb->rx_data_used, > > + struct rx_usb_ctrl_block, list); > > + > > + spin_unlock_irqrestore(&rtwusb->rx_data_list_lock, flags); > > + > > + if (!rxcb) > > + break; > > + > > + usb_kill_urb(rxcb->rx_urb); > > + > > + spin_lock_irqsave(&rtwusb->rx_data_list_lock, flags); > > + list_move(&rxcb->list, &rtwusb->rx_data_free); > > + } > > +} > > The spin_lock pairs are not intuitive. > Can we change this chunk to > > while (true) { > spin_lock(); > rxcb = list_first_entry_or_null(); > spin_unlock() > > if (!rxcb) > return; > > usb_free_urb(); > > spin_lock(); > list_del(); > spin_unlock(); > } > > The drawback is lock/unlock twice in single loop. Yes, that's why I did it the way I did ;) How about: while (true) { unsigned long flags; spin_lock_irqsave(&rtwusb->rx_data_list_lock, flags); rxcb = list_first_entry_or_null(&rtwusb->rx_data_free, struct rx_usb_ctrl_block, list); if (rxcb) list_del(&rxcb->list); spin_unlock_irqrestore(&rtwusb->rx_data_list_lock, flags); if (!rxcb) break; usb_free_urb(rxcb->rx_urb); } Sascha -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
