Re: [PATCH v2 2/7] USB: serial: handle suspend failure path correctly
From: Johan Hovold <hidden>
Date: 2013-03-14 11:10:10
Also in:
netdev
On Fri, Mar 08, 2013 at 12:15:19AM +0800, Ming Lei wrote:
quoted hunk ↗ jump to hunk
This patch kills traffic even though type->suspend returns failure inside usb_serial_suspend from system sleep context because USB core ignores the failiure and lets system sleep go ahread, so the serial URB traffic need to be killed in this case. Cc: Johan Hovold <redacted> Signed-off-by: Ming Lei <redacted> --- drivers/usb/serial/usb-serial.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c index a19ed74..9d0b9c8 100644 --- a/drivers/usb/serial/usb-serial.c +++ b/drivers/usb/serial/usb-serial.c@@ -1142,10 +1142,11 @@ int usb_serial_suspend(struct usb_interface *intf, pm_message_t message) if (serial->type->suspend) { r = serial->type->suspend(serial, message); - if (r < 0) { + if (r < 0 && PMSG_IS_AUTO(message)) { serial->suspending = 0; goto err_out; } + /* TODO: resume() might need to handle suspend failure */ } for (i = 0; i < serial->num_ports; ++i) {
Sorry for the late reply. The usb-serial subdriver suspend callbacks do not and must not return non-zero if !PMSG_IS_AUTO(message) so adding code to handle that case merely obfuscates this fact. I'd rather see this documented with a comment just as Bjørn suggested for cdc_mbim and qmi_wwan. Thanks, Johan