Hello all I have done modprobe g_serial on my BeagleBoard to use usb as serial port on Beagleboard I have taken the program on the link below as suggested by Jan axelson ... for testing uart communication on BeagleBoard xm http://www.lvr.com/code/usb_serial_port.c I have connected BeagleBoard uart to windows hyperterminal and its connected successfully . Now i am able to write on uart from Beagleboard side .. but as i read on Beagleboard ..i.e write something on Hyperterminal ..at once These ERROR MESSAGES come on Beagleboard !! [ 236.729919] musb g_serial gadget disconnected. [ 238.990112] g_serial gadget: high speed config #2: CDC ACM config [ 274.613616] ------------[ cut here ]------------ [ 274.618286] WARNING: at kernel/mutex.c:207 __mutex_lock_slowpath+0x6c/ 0x278() [ 274.625488] Modules linked in: g_serial rfcomm ipv6 hidp l2cap bluetooth rfkill [ 274.632965] [<c0040c40>] (unwind_backtrace+0x0/0xdc) from [<c006cdb4>] (warn_slowpath_common+0x4c/0x80) [ 274.642425] [<c006cdb4>] (warn_slowpath_common+0x4c/0x80) from [<c04852a0>] (__mutex_lock_slowpath+0x6c/0x278) [ 274.652496] [<c04852a0>] (__mutex_lock_slowpath+0x6c/0x278) from [<c04854b8>] (mutex_lock+0xc/0x1c) [ 274.661621] [<c04854b8>] (mutex_lock+0xc/0x1c) from [<c029c014>] (echo_set_canon_col+0x18/0x40) [ 274.670379] [<c029c014>] (echo_set_canon_col+0x18/0x40) from [<c029e4d8>] (n_tty_receive_buf+0xc54/0xf38) [ 274.680023] [<c029e4d8>] (n_tty_receive_buf+0xc54/0xf38) from [<c02a0c70>] (flush_to_ldisc+0x114/0x1e0) [ 274.689514] [<c02a0c70>] (flush_to_ldisc+0x114/0x1e0) from [<bf09ce3c>] (gs_rx_push+0x140/0x220 [g_serial]) [ 274.699340] [<bf09ce3c>] (gs_rx_push+0x140/0x220 [g_serial]) from [<c0072e00>] (tasklet_action+0x74/0xbc) [ 274.708984] [<c0072e00>] (tasklet_action+0x74/0xbc) from [<c0073400>] (__do_softirq+0xe8/0x1f0) [ 274.717742] [<c0073400>] (__do_softirq+0xe8/0x1f0) from [<c007354c>] (irq_exit+0x44/0x98) [ 274.725982] [<c007354c>] (irq_exit+0x44/0x98) from [<c003b078>] (asm_do_IRQ+0x78/0x98) [ 274.733947] [<c003b078>] (asm_do_IRQ+0x78/0x98) from [<c003bd40>] (__irq_usr+0x40/0xa0) [ 274.742004] Exception stack(0xdfbabfb0 to 0xdfbabff8) [ 274.747100] bfa0: 00000000 be9bbcdd 0000000a 00000003 [ 274.755340] bfc0: 40020000 00000000 00008588 00000003 00000000 00000000 40025000 be9bbccc [ 274.763580] bfe0: 00000000 be9bbcb8 000089f0 400da29c 60000010 ffffffff [ 274.770233] ---[ end trace c191d2c1d7b00f1e ]--- please help me to interpret and how could i correct this ... Thanks Nidhi -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html