diff options
author | Geert Uytterhoeven <geert+renesas@glider.be> | 2015-08-21 20:02:38 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-10-04 17:33:48 +0100 |
commit | f5835c1d0e30c7d0a48aa36e3a353c7d54ace470 (patch) | |
tree | 31ff9d81c17d0dad8c8f6df7bedf60c75f71722a /drivers/tty/serial/sh-sci.c | |
parent | beb9487b0c18650da16ef088ec859d6e421fade1 (diff) | |
download | op-kernel-dev-f5835c1d0e30c7d0a48aa36e3a353c7d54ace470.zip op-kernel-dev-f5835c1d0e30c7d0a48aa36e3a353c7d54ace470.tar.gz |
serial: sh-sci: Improve comments for DMA timeout calculation
Reformat, grammar improvements, use "ms" instead of "msec".
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/sh-sci.c')
-rw-r--r-- | drivers/tty/serial/sh-sci.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 340700a..cfef543 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -2015,13 +2015,13 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios, #ifdef CONFIG_SERIAL_SH_SCI_DMA /* * Calculate delay for 2 DMA buffers (4 FIFO). - * See serial_core.c::uart_update_timeout(). With 10 - * bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above function - * calculates 1 jiffie for the data plus 5 jiffies for the "slop(e)." - * Then below we calculate 5 jiffies (20ms) for 2 DMA buffers (4 FIFO - * sizes), but when performing a faster transfer, value obtained by - * this formula is may not enough. Therefore, if value is smaller than - * 20msec, this sets 20msec as timeout of DMA. + * See serial_core.c::uart_update_timeout(). + * With 10 bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above + * function calculates 1 jiffie for the data plus 5 jiffies for the + * "slop(e)." Then below we calculate 5 jiffies (20ms) for 2 DMA + * buffers (4 FIFO sizes), but when performing a faster transfer, the + * value obtained by this formula is too small. Therefore, if the value + * is smaller than 20ms, use 20ms as the timeout value for DMA. */ if (s->chan_rx) { unsigned int bits; |