Hi, Andrew and Denis,
>-----Original Message----- >From: ofono-boun...@ofono.org [mailto:ofono-boun...@ofono.org] On Behalf Of >Denis Kenzior >Sent: Thursday, February 11, 2010 6:38 AM >To: ofono@ofono.org >Subject: Re: [PATCH] Add support of Huawei EM770 modem > >Hi Yang, > >> There are two known parts of code that may have problem and need your >> comments. 1. Once connecting this modem to PC via USB, we can get 5 tty >> ports: ttyUSB0, ttyUSB1, ttyUSB2, ttyUSB3 and ttyUSB4. The correct way to >> talk to this modem is using ttyUSB2. I'm not sure if I handled this >> correctly in file udev.c. 2. When creating the modem, a global modem id > >So Andrew had it exactly correct, you can't just use ttyUSB2 here. Most >devices have other udev attributes you can examine for what type of port it >is, to help you pick the right one. Perhaps examination of 'udevadm info -- >attribute-walk --path=<device>' might be in order? The check of "ttyUSB2" in my code is not the same as you see in /dev directory. Below is the output of this modem along its path (not a full path and I removed some unimportant attributes in each path): looking at device '/devices/pci0000:00/0000:00:1a.7/usb1/1-3/1-3:1.2/ttyUSB2/tty/ttyUSB2': (device1) KERNEL=="ttyUSB2" SUBSYSTEM=="tty" DRIVER=="" looking at parent device '/devices/pci0000:00/0000:00:1a.7/usb1/1-3/1-3:1.2/ttyUSB2': (device2) KERNELS=="ttyUSB2" SUBSYSTEMS=="usb-serial" DRIVERS=="option1" ATTRS{port_number}=="0" looking at parent device '/devices/pci0000:00/0000:00:1a.7/usb1/1-3/1-3:1.2': (device3) KERNELS=="1-3:1.2" SUBSYSTEMS=="usb" DRIVERS=="option" ATTRS{bInterfaceNumber}=="02" ATTRS{modalias}=="usb:v12D1p1404d0000dc00dsc00dp00icFFiscFFipFF" ATTRS{supports_autosuspend}=="0" looking at parent device '/devices/pci0000:00/0000:00:1a.7/usb1/1-3':(device4) KERNELS=="1-3" ATTRS{configuration}=="Huawei Configuration" ATTRS{bNumInterfaces}==" 5" ATTRS{idVendor}=="12d1" ATTRS{idProduct}=="1404" ATTRS{manufacturer}=="HUAWEI Technology" ATTRS{product}=="HUAWEI Mobile" In oFono code, "device4" represents the modem, while "device1" is the udev_device when calling function add_huawei_em770(modem, udev_device). When I check if it's ttyUSB2 or not in my code, I think I'm checking the device1 and its sysname (Showed as KERNEL in device1, but not the one showed in /dev directory), and in the context of this modem (device4). I do believe there may be some other ttyUSB2 in the system, for example, we have another em770 modem pluged in. But these two ttyUSB2 are in different context. I ever tried to change the name showed in /dev directory by writing some udev rules, but this sysname (KERNEL) seems stable (It's still ttyUSB2). Is it possible this sysname gets changed under some circumstance expect the kernel or driver changes? If not, I still think it's safe and convenient to check this value here. Maybe we can use another attribute "bInterfaceNumber". But this attribute is udev_device's parent's parent (device3), so the code could become more complicated. What's your opinion? > >> will be appended to the name of it while constructing the path. This modem >> has name "huawei_em770", thus the path becomes things like >> "/huawei_em7700" or "/huawei_em7701". This looks strange. Need I change >> the name of this modem, or can we use some smarter way to append the modem >> id? > >We should be using the udev short serial from the device. For some reason >this seems to be failing on the EM770. Can you check whether get_serial >returns NULL for this device? Yes. get_serial() will return NULL, and we just use its type as name. >Regards, >-Denis >_______________________________________________ >ofono mailing list >ofono@ofono.org >http://lists.ofono.org/listinfo/ofono Regards, -Yang _______________________________________________ ofono mailing list ofono@ofono.org http://lists.ofono.org/listinfo/ofono
