2020-09-01 05:02:03

by William Sung

Subject: [PATCH 2/2] usb: serial: usb_wwan: Fix lackage for Quectel EG95 LTE modem support

As required by the USB protocol, add zero packet support for Quectel
EG95 LTE modem module.

Fixes: f815dd5cf48b ("net: usb: qmi_wwan: add support for Quectel EG95
LTE modem"

Signed-off-by: William Sung <[email protected]>
---
drivers/usb/serial/usb_wwan.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/serial/usb_wwan.c b/drivers/usb/serial/usb_wwan.c
index 4b9845807bee..75495c939ac6 100644
--- a/drivers/usb/serial/usb_wwan.c
+++ b/drivers/usb/serial/usb_wwan.c
@@ -467,6 +467,7 @@ static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
struct usb_serial *serial = port->serial;
struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
struct urb *urb;
+ struct usb_device_descriptor *desc = &serial->dev->descriptor;

urb = usb_alloc_urb(0, GFP_KERNEL); /* No ISO */
if (!urb)
@@ -476,8 +477,15 @@ static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
usb_sndbulkpipe(serial->dev, endpoint) | dir,
buf, len, callback, ctx);

- if (intfdata->use_zlp && dir == USB_DIR_OUT)
- urb->transfer_flags |= URB_ZERO_PACKET;
+ if (dir == USB_DIR_OUT) {
+ if (intfdata->use_zlp)
+ urb->transfer_flags |= URB_ZERO_PACKET;
+
+ /* Add zero packet support for Quectel EG95 */
+ if (desc->idVendor == cpu_to_le16(0x2C7C) &&
+ desc->idProduct == cpu_to_le16(0x0195))
+ urb->transfer_flags |= URB_ZERO_PACKET;
+ }

return urb;
}
--
2.17.1

2020-09-01 14:27:32

by Daniele Palmas

Subject: Re: [PATCH 2/2] usb: serial: usb_wwan: Fix lackage for Quectel EG95 LTE modem support

Hi William,

Il giorno mar 1 set 2020 alle ore 07:14 William Sung
<[email protected]> ha scritto:
>
> As required by the USB protocol, add zero packet support for Quectel
> EG95 LTE modem module.
>
> Fixes: f815dd5cf48b ("net: usb: qmi_wwan: add support for Quectel EG95
> LTE modem"

If I'm not wrong, that commit is just related to qmi_wwan.

>
> Signed-off-by: William Sung <[email protected]>
> ---
> drivers/usb/serial/usb_wwan.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/serial/usb_wwan.c b/drivers/usb/serial/usb_wwan.c
> index 4b9845807bee..75495c939ac6 100644
> --- a/drivers/usb/serial/usb_wwan.c
> +++ b/drivers/usb/serial/usb_wwan.c
> @@ -467,6 +467,7 @@ static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
> struct usb_serial *serial = port->serial;
> struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
> struct urb *urb;
> + struct usb_device_descriptor *desc = &serial->dev->descriptor;
>
> urb = usb_alloc_urb(0, GFP_KERNEL); /* No ISO */
> if (!urb)
> @@ -476,8 +477,15 @@ static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
> usb_sndbulkpipe(serial->dev, endpoint) | dir,
> buf, len, callback, ctx);
>
> - if (intfdata->use_zlp && dir == USB_DIR_OUT)
> - urb->transfer_flags |= URB_ZERO_PACKET;
> + if (dir == USB_DIR_OUT) {
> + if (intfdata->use_zlp)
> + urb->transfer_flags |= URB_ZERO_PACKET;
> +
> + /* Add zero packet support for Quectel EG95 */
> + if (desc->idVendor == cpu_to_le16(0x2C7C) &&
> + desc->idProduct == cpu_to_le16(0x0195))
> + urb->transfer_flags |= URB_ZERO_PACKET;
> + }

Why not simply add the ZLP flag in option for that device?

Regards,
Daniele

>
> return urb;
> }
> --
> 2.17.1
>