Hi Alan, On Mon, Feb 11, 2019 at 8:00 PM Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > > On Mon, 11 Feb 2019, Martin Townsend wrote: > > > I can confirm that do_start_stop is called and the code where it > > closes the LUN captures the EJECT (tested using Linux and Windows > > host). > > > > up_read(&common->filesem); > > down_write(&common->filesem); > > printk(KERN_ERR "do_start_stop -> fsg_lun_close (EJECT)\n"); > > fsg_lun_close(curlun); > > up_write(&common->filesem); > > down_read(&common->filesem); > > > > Thank you very much for this as we were about to abandon MSG :) > > > > I have one more problem, if I specify removable=y I can't re-insert > > the device and after reading the documentation it looks like I have to > > reset the backing file attribute in sysfs but I can't seem to write to > > the file attribute: > > root@beeker:/sys/module/g_mass_storage/parameters# ls -la > > total 0 > > drwxr-xr-x 2 root root 0 Feb 4 19:16 . > > drwxr-xr-x 6 root root 0 Feb 4 19:15 .. > > -r--r--r-- 1 root root 4096 Feb 4 19:16 bcdDevice > > -r--r--r-- 1 root root 4096 Feb 4 19:16 cdrom > > -r--r--r-- 1 root root 4096 Feb 4 19:16 file > > -r--r--r-- 1 root root 4096 Feb 4 19:16 iManufacturer > > -r--r--r-- 1 root root 4096 Feb 4 19:16 iProduct > > -r--r--r-- 1 root root 4096 Feb 4 19:16 iSerialNumber > > -r--r--r-- 1 root root 4096 Feb 4 19:16 idProduct > > -r--r--r-- 1 root root 4096 Feb 4 19:16 idVendor > > -r--r--r-- 1 root root 4096 Feb 4 19:16 luns > > -r--r--r-- 1 root root 4096 Feb 4 19:16 nofua > > -r--r--r-- 1 root root 4096 Feb 4 19:16 removable > > -r--r--r-- 1 root root 4096 Feb 4 19:16 ro > > -r--r--r-- 1 root root 4096 Feb 4 19:16 stall > > > > Even if I set the file to writable I just get an IO error. > > root@beeker:/sys/module/g_mass_storage/parameters# chmod 666 file > > root@beeker:/sys/module/g_mass_storage/parameters# echo > > /data/mass_storage/msg.bin > file > > -sh: echo: write error: Input/output error > > > > Any ideas as to why I'm seeing this? If I remove and reinsert the > > g_mass_storage gadget kernel module I can re-insert the device. I > > would like to build the gadget driver into the kernel as mass storage > > is the only gadget function we have and I believe it can be built into > > the kernel if this is the case. > > You're trying to write to the wrong sysfs file. > /sys/module/g_mass_storage/parameters contains the parameters that you > specified when g_mass_storage was loaded; you can't change them. The > file you want is > > /sys/class/udc/XXX/device/gadget/lun0/file > > (fill in the XXX with the appropriate name for your UDC). > oops. thanks for clearing that up for me :) > Alan Stern >
