Flashing is a technique to break out of the data/PPP stream and
re-enter command stream (like +++) and MM uses it in the generic
paths in various cases. But devices that don't need it (ie, ones
with at least one AT capable port that won't be used for data)
now sometimes appear to have side-effects.
The Ericsson F5521gw firmware R2A07 resets port attributes like
echo and &C and such when the port is flashed, leading to
confusion on the part of MM. Since the Ericsson devices will
always have at least one free AT port they don't need flashing
anyway.
This feature is initially disabled for all modems, but plugins can enable it by
setting a value greater than 0 for the "max-timeouts" property when creating the
modem object.
It's only used during probing where some port types (Sierra CnS
and some Icera devices) may send streams of data that we can't
understand until we close the port. It interferes with some SMS
operations, so turn it off for ports opened after probing.
This specifically fixes a regression with Novatel GSM secondary
AT port enablement, where the inital pin check closed the port
before the Novatel plugin could send the command to flip secondary
ports to AT mode.
But it's useful elsewhere too, and simplifies a bunch of the PIN
checking code which had to use various ugly methods to track whether
to close the port or not after checking the PIN.
Some ports we know we shouldn't use when we get certain responses
from them. Reading from these ports triggers kernel bugs (at least
on 2.6.31 and 2.6.32) relating to flow control in some drivers
(*cough* hso *cough*), so lets try not to aggravate the kernel too
much. This happens on Icera-based Option devices like the GI0322
(AT&T Quicksilver) for example.
(note: AFAICT this doesn't have any relation to the recent XON/XOFF
patch, since I get this problem without the XON/XOFF patch on both
2.6.31 and 2.6.32 as well)
---
BUG: sleeping function called from invalid context at kernel/mutex.c:94
in_atomic(): 1, irqs_disabled(): 1, pid: 9295, name: modem-manager
Pid: 9295, comm: modem-manager Not tainted 2.6.32.9-67.fc12.x86_64 #1
Call Trace:
<IRQ> [<ffffffff81045d41>] __might_sleep+0xed/0xef
[<ffffffff81454dd0>] mutex_lock+0x24/0x50
[<ffffffff8104811e>] ? enqueue_task_fair+0x2a/0x6d
[<ffffffff812af79f>] tty_throttle+0x1b/0x49
[<ffffffff812af0d9>] n_tty_receive_buf+0xdbb/0xe12
[<ffffffff810459fd>] ? task_rq_unlock+0x11/0x13
[<ffffffff81050c5c>] ? try_to_wake_up+0x2f3/0x305
[<ffffffff8110de0c>] ? __kmalloc+0x37/0x15e
[<ffffffff8110de42>] ? __kmalloc+0x6d/0x15e
[<ffffffff812b12c9>] flush_to_ldisc+0xf8/0x18d
[<ffffffff812b13ae>] tty_flip_buffer_push+0x50/0x61
[<ffffffffa040ccd5>] put_rxbuf_data+0xea/0x124 [hso]
[<ffffffffa040cd97>] put_rxbuf_data_and_resubmit_bulk_urb+0x21/0x6b [hso]
[<ffffffffa040d0b1>] hso_std_serial_read_bulk_callback+0x14d/0x15f [hso]
[<ffffffff8132edf7>] ? dma_unmap_single_attrs.clone.0+0x38/0x3a
[<ffffffff8132ef74>] usb_hcd_giveback_urb+0x91/0xc5
[<ffffffff813417c8>] ehci_urb_done+0x7b/0x90
[<ffffffff81050c5c>] ? try_to_wake_up+0x2f3/0x305
[<ffffffff81341b45>] qh_completions+0x368/0x4b9
[<ffffffff8103e7a0>] ? __wake_up_common+0x4e/0x84
[<ffffffff81343f70>] ehci_work+0x95/0x732
[<ffffffff81045b53>] ? __wake_up+0x44/0x4d
[<ffffffff81070490>] ? insert_work+0x8e/0x9b
[<ffffffff81345f01>] ehci_irq+0x2be/0x420
[<ffffffff8107071a>] ? __queue_work+0x3a/0x41
[<ffffffff81049e43>] ? resched_cpu+0x6e/0x77
[<ffffffff8107075d>] ? delayed_work_timer_fn+0x3c/0x3e
[<ffffffff810b0e44>] ? __rcu_process_callbacks+0x7d/0x28a
[<ffffffff8132e846>] usb_hcd_irq+0x3f/0x7b
[<ffffffff810acd61>] handle_IRQ_event+0x60/0x121
[<ffffffff810aeb8e>] handle_fasteoi_irq+0x8b/0xc7
[<ffffffff81014625>] handle_irq+0x8b/0x96
[<ffffffff81459c14>] do_IRQ+0x5c/0xbc
[<ffffffff81012693>] ret_from_intr+0x0/0x11
For QCDM devices we want most of what MMSerialPort does, but not
the AT command handling stuff since the commands and responses
aren't AT commands nor are they even strings. So convert everything
that MMSerialPort does into a GByteArray, and let MMAtSerialPort
handle the conversion to strings when necessary.
Previously, a few operations (like disable) could trigger a modem
flash in parallel with another flash. That's wrong, don't allow
that. At the same time, add in finer-grained error checking on
serial port speed operations, and fix a GSM generic bug that would
send the POWER_UP string on disable.
So many modems just don't implement carrier detect that it makes
the previous 'connected' logic useless, so base it off connect/disconnect
and fix up a few places that didn't check connect status before
trying to send commands. Also ensure the serial port is unlocked
for PPP to use when connected.
Get rid of dependency on HAL, using libgudev instead. Fix up the plugin API
to no longer use either HAL or udev defines, but let plugins use whatever
mechanism they want for getting more information out of the device given the
subsystem and device node name.
Modems are now defined as "master" devices which "own" a one or more ports.
A port could be a serial tty device or a network device or whatever. The
plugin figures out whether it supports a given port or not and then assigns
it to a new or existing modem. Modems now have a 'valid' property that
should be set to TRUE when the modem has enough ports to operate correctly.
For devices (ex. 'hso') that use a network device for data transfer, the
modem would need to grab at least one TTY and the network device associated
with that physical device to be 'valid'.
Also move the generic modem support code to a plugin like other modem plugins,
and change the I-support-this-device mechanism to return a number indicating
the level of support. For example, the generic plugin would return a quite
low number if the device indicates via probing that it can do GSM or CDMA, but
a more specific plugin can indicate better support for the device, and thus
the more specific plugin would win control.
Aleksander Morgado
Dan Williams
Nathan Williams