> Usually, the developer him(her)self wants to read it to know if current > USB gadget enumerated and what speed is recognized, reading from the > console by eyes is the quickest way. Without this message, there is no > any messages when the USB gadget connects to host. Yes, especially when enumeration USB3 failed then downgrade to USB2. > If enable debug message, there are too many messages, This is the reason why it is not a good solution, when I just need to confirm what the enumeration result is. -- Thanks, Albert On Fri, Jan 8, 2021 at 10:16 AM Peter Chen <hzpeterchen@xxxxxxxxx> wrote: > > On 21-01-07 10:50:38, Greg KH wrote: > > On Thu, Jan 07, 2021 at 09:06:04AM +0000, Albert Wang wrote: > > > This reverts commit 1cbfb8c4f62d667f6b8b3948949737edb92992cc. > > > > > > The log of USB enumeration result is a useful log and only occupies > > > one line especially when USB3 enumeration failed and then downgrade > > > to USB2. > > > > > > Signed-off-by: Albert Wang <albertccwang@xxxxxxxxxx> > > > --- > > > drivers/usb/gadget/composite.c | 6 +++--- > > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c > > > index c6d455f2bb92..5b0d6103a63d 100644 > > > --- a/drivers/usb/gadget/composite.c > > > +++ b/drivers/usb/gadget/composite.c > > > @@ -840,9 +840,9 @@ static int set_config(struct usb_composite_dev *cdev, > > > result = 0; > > > } > > > > > > - DBG(cdev, "%s config #%d: %s\n", > > > - usb_speed_string(gadget->speed), > > > - number, c ? c->label : "unconfigured"); > > > + INFO(cdev, "%s config #%d: %s\n", > > > + usb_speed_string(gadget->speed), > > > + number, c ? c->label : "unconfigured"); > > > > When everything is working properly, the kernel should be quiet. If you > > have to see this message, you can turn it on at runtime, as Felipe > > pointed out, to enable it for your system. But it's not a good default > > thing to have. > > For most production kernel (or kernel ready for customers), it may not enable > CONFIG_DYNAMIC_DEBUG. > > > > > What do you need to see this message for? What tool relies on it? Who > > reads it? > > > > Usually, the developer him(her)self wants to read it to know if current > USB gadget enumerated and what speed is recognized, reading from the > console by eyes is the quickest way. Without this message, there is no > any messages when the USB gadget connects to host. > > If enable debug message, there are too many messages, but I think most > developers may only need one information message to know if enumeration > is established correctly. > > -- > > Thanks, > Peter Chen >
