kernel.git/include/linux/tty.h, branch linux-2.6.31.y

tty: Add a full port_close function

2009-10-05T16:32:34Z

commit 7ca0ff9ab3218ec443a7a9ad247e4650373ed41e upstream. Now we are extracting out methods for shutdown and the like we can add a proper tty_port_close method that knows all the innards of the tty closing process and hides the lot from the caller. At some point in the future this will be paired with a similar open() helper and the drivers can stick to hardware management. Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

pty: avoid forcing 'low_latency' tty flag

2009-07-29T19:15:56Z

We really don't want to mark the pty as a low-latency device, because as Alan points out, the ->write method can be called from an IRQ (ppp?), and that means we can't use ->low_latency=1 as we take mutexes in the low_latency case. So rather than using low_latency to force the written data to be pushed to the ldisc handling at 'write()' time, just make the reader side (or the poll function) do the flush when it checks whether there is data to be had. This also fixes the problem with lost data in an emacs compile buffer (bugzilla 13815), and we can thus revert the low_latency pty hack (commit 3a54297478e6578f96fd54bf4daa1751130aca86: "pty: quickfix for the pty ENXIO timing problems"). Signed-off-by: OGAWA Hirofumi Tested-by: Aneesh Kumar K.V [ Modified to do the tty_flush_to_ldisc() inside input_available_p() so that it triggers for both read and poll() - Linus] Signed-off-by: Linus Torvalds

tty: rewrite the ldisc locking

2009-06-11T15:51:01Z

There are several pretty much unfixable races in the old ldisc code, especially with respect to pty behaviour and also to hangup. It's easier to rewrite the code than simply try and patch it up. This patch - splits the ldisc from the tty (so we will be able to refcount it more cleanly later) - introduces a mutex lock for ldisc changing on an active device - fixes the complete mess that hangup caused - implements hopefully correct setldisc/close/hangup locking There are still some problems around pty pairs that have always been there but at least it is now possible to understand the code and fix further problems. This fixes the following known bugs - hang up can leak ldisc references - hang up may not call open/close on ldisc in a matched way - pty/tty pairs can deadlock during an ldisc change - reading the ldisc proc files can cause every ldisc to be loaded and probably a few other of the mysterious ldisc race reports. I'm sure it also adds the odd new one. Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds

tty: Extract various bits of ldisc code

2009-06-11T15:51:01Z

Before trying to tackle the ldisc bugs the code needs to be a good deal more readable, so do the simple extractions of routines first. Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds

tty: Implement a drain delay in the tty port

2009-06-11T15:50:56Z

We need this for devices that cannot flush and wait, but which do not order data and modem events. Without it we will hang up before all the data clears the hardware. Needed for the USB changes. Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds

tty: Add carrier processing on close to the tty_port core

2009-06-11T15:50:56Z

Some drivers implement this internally, others miss it out. Push the behaviour into the core code as that way everyone will do it consistently. Update the dtr rts method to raise or lower depending upon flags. Having a single method in this style fits most of the implementations more cleanly than two funtions. We need this in place before we tackle the USB side Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds

tty: Introduce some close helpers for ports

2009-01-02T18:19:40Z

Again this is a lot of common code we can unify Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds

tty: Introduce a tty_port generic block_til_ready

2009-01-02T18:19:39Z

Start sucking more commonality out of the drivers into a single piece of core code. Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds

isicom: redo locking to use tty port locks

2009-01-02T18:19:38Z

This helps set the basis for moving block_til_ready into common code. We also introduce a tty_port_hangup helper as this will also be generally needed. Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds

tty: Pull the dtr raise into tty port

2009-01-02T18:19:38Z

This moves another per device special out of what should be shared open wait paths into private methods Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds