[PATCH] drivers/tty/hvc/hvc_tile.c: properly return -EAGAIN

From: Chris Metcalf
Date: Tue May 05 2015 - 13:11:39 EST


We were returning zero if no bytes could be written to the Tilera
hypervisor console device, but this causes the output to be truncated.
By returning -EAGAIN the tty hvc driver will come back and try again,
which gives the semantics we want, and avoids dropping console output.

Signed-off-by: Chris Metcalf <cmetcalf@xxxxxxxxxx>
---
I have queued this in the tile tree as a tile-specific device, but
if someone would prefer to pick it up for a tty or tty/hvc tree,
that's fine too; just let me know.

drivers/tty/hvc/hvc_tile.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/hvc/hvc_tile.c b/drivers/tty/hvc/hvc_tile.c
index 3f6cd3102db5..9da1e842bbe9 100644
--- a/drivers/tty/hvc/hvc_tile.c
+++ b/drivers/tty/hvc/hvc_tile.c
@@ -51,7 +51,8 @@ int tile_console_write(const char *buf, int count)
_SIM_CONTROL_OPERATOR_BITS));
return 0;
} else {
- return hv_console_write((HV_VirtAddr)buf, count);
+ /* Translate 0 bytes written to EAGAIN for hvc_console_print. */
+ return hv_console_write((HV_VirtAddr)buf, count) ?: -EAGAIN;
}
}

--
2.1.2

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