]> git.karo-electronics.de Git - karo-tx-linux.git/commit
hvc_console: Improve tty/console put_chars handling
authorHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Tue, 5 Jul 2011 21:50:18 +0000 (21:50 +0000)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Tue, 19 Jul 2011 05:13:05 +0000 (15:13 +1000)
commit8c2381af0d3ef62a681dac5a141b6dabb27bf2e1
tree42cd8aaecca37a7fce9d81d20fcd78f9d86647b1
parent63f21a56f1cc0b800a4c00349c59448f82473d19
hvc_console: Improve tty/console put_chars handling

Currently, the hvc_console_print() function drops console output if the
hvc backend's put_chars() returns 0.  This patch changes this behavior
to allow a retry through returning -EAGAIN.

This change also affects the hvc_push() function.  Both functions are
changed to handle -EAGAIN and to retry the put_chars() operation.

If a hvc backend returns -EAGAIN, the retry handling differs:

  - hvc_console_print() spins to write the complete console output.
  - hvc_push() behaves the same way as for returning 0.

Now hvc backends can indirectly control the way how console output is
handled through the hvc console layer.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Acked-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
drivers/tty/hvc/hvc_console.c