[Gumstix-users] RTS/CTS on HWUART

[Andrei R. <ar...@ya...>]

Hi,
trying to use RTS/CTS on HWUART got a problem.
When both pins left unconnected, nothing
gets out of the Gumstix (via breakout-gs)
whether RTS/CTS flow control is enabled or not
('set flow rts/cts' in wermit and tcsetattr()
in my own programm).
But in the opposite direction HWUART receives data
just fine. Then if I connect RTS to CTS
on the Gumstix side, data starts to flow in
both direction, but only when I'm not enabling
RTS/CTS in software. Any attempts to enable
it crashes the system in a couple of seconds
(not instantly). The message is below.
So, anyone had this or similar problems ?
Could someone reproduce it - it's es easy as
connecting 2 pins on HWUART and trying wermit with
rts/cts on.
-Andrei.

BTW, I configure HWUART pins as prescribed:
Set (AF1,in,set) via /proc/gpio/GPIO49
Set (AF1,out,set) via /proc/gpio/GPIO48
Set (AF1,in,set) via /proc/gpio/GPIO50
Set (AF1,out,set) via /proc/gpio/GPIO51

BUG: soft lockup detected on CPU#0!
[<c001ff68>] (dump_stack+0x0/0x14) from [<c0048be8>]
(softlockup_tick+0xac/0xe4)
[<c0048b3c>] (softlockup_tick+0x0/0xe4) from
[<c00354f4>] (run_local_timers+0x18/0x1c)
 r7 = C0365B7C  r6 = C01C2DF0  r5 = 00000000  r4 =
C22032E0
[<c00354dc>] (run_local_timers+0x0/0x1c) from
[<c003553c>] (update_process_times+0x44/0x6c)
[<c00354f8>] (update_process_times+0x0/0x6c) from
[<c001fba8>] (timer_tick+0xc8/0xe4)
 r5 = C01BD5CC  r4 = C0365B7C 
[<c001fae0>] (timer_tick+0x0/0xe4) from [<c0025820>]
(pxa_timer_interrupt+0x64/0xd4)
 r6 = 00000013  r5 = C01C2DE0  r4 = C0364000 
[<c00257bc>] (pxa_timer_interrupt+0x0/0xd4) from
[<c0049170>] (handle_IRQ_event+0xd4/0x118)
 r7 = 00000000  r6 = 00000013  r5 = C018EB94  r4 =
C018A4C0
[<c004909c>] (handle_IRQ_event+0x0/0x118) from
[<c004a574>] (handle_level_irq+0xe4/0x168)
[<c004a490>] (handle_level_irq+0x0/0x168) from
[<c001c728>] (asm_do_IRQ+0x40/0x50)
 r8 = 00010105  r7 = 00010106  r6 = 04000000  r5 =
F2D00000
 r4 = FFFFFFFF 
[<c001c6e8>] (asm_do_IRQ+0x0/0x50) from [<c001b9d8>]
(__irq_svc+0x38/0x78)
[<c0026c80>] (__wake_up+0x0/0x60) from [<c00f5ae0>]
(serial_pxa_irq+0x378/0x474)
 r5 = 00000001  r4 = C0194378 
[<c00f5768>] (serial_pxa_irq+0x0/0x474) from
[<c0049170>] (handle_IRQ_event+0xd4/0x118)
[<c004909c>] (handle_IRQ_event+0x0/0x118) from
[<c004a574>] (handle_level_irq+0xe4/0x168)
[<c004a490>] (handle_level_irq+0x0/0x168) from
[<c001c728>] (asm_do_IRQ+0x40/0x50)
 r8 = 00000104  r7 = 00000105  r6 = 00000080  r5 =
F2D00000
 r4 = FFFFFFFF 
[<c001c6e8>] (asm_do_IRQ+0x0/0x50) from [<c001b9d8>]
(__irq_svc+0x38/0x78)
[<c0030888>] (__do_softirq+0x0/0xc8) from [<c0030af0>]
(irq_exit+0x44/0x58)
 r7 = 00000003  r6 = 00000080  r5 = F2D00000  r4 =
C0364000
[<c0030aac>] (irq_exit+0x0/0x58) from [<c001c72c>]
(asm_do_IRQ+0x44/0x50)
 r4 = FFFFFFFF 
[<c001c6e8>] (asm_do_IRQ+0x0/0x50) from [<c001b9d8>]
(__irq_svc+0x38/0x78)
[<c00f5ef0>] (serial_pxa_set_termios+0x0/0x244) from
[<c00f262c>] (uart_change_speed+0x84/0x88)
[<c00f25a8>] (uart_change_speed+0x0/0x88) from
[<c00f3d50>] (uart_set_termios+0x6c/0x290)
 r4 = C0364000 
[<c00f3ce4>] (uart_set_termios+0x0/0x290) from
[<c00f10ec>] (set_termios+0x404/0x470)
[<c00f0ce8>] (set_termios+0x0/0x470) from [<c00f1324>]
(n_tty_ioctl+0x15c/0x5e4)
[<c00f11c8>] (n_tty_ioctl+0x0/0x5e4) from [<c00ecf60>]
(tty_ioctl+0xdd0/0xe30)
 r6 = BEE03768  r5 = C21F5800  r4 = FFFFFFEA 
[<c00ec190>] (tty_ioctl+0x0/0xe30) from [<c007a1b4>]
(do_ioctl+0x80/0x94)
[<c007a134>] (do_ioctl+0x0/0x94) from [<c007a4a8>]
(vfs_ioctl+0x2e0/0x300)
 r7 = 00000003  r6 = BEE03768  r5 = FFFFFFF7  r4 =
C02641A0
[<c007a1c8>] (vfs_ioctl+0x0/0x300) from [<c007a508>]
(sys_ioctl+0x40/0x5c)
 r8 = C001BFA4  r7 = 00000036  r6 = 00005403  r5 =
FFFFFFF7
 r4 = C02641A0 
[<c007a4c8>] (sys_ioctl+0x0/0x5c) from [<c001be00>]
(ret_fast_syscall+0x0/0x2c)
 r6 = BEE03A4C  r5 = 00000000  r4 = 00000A30