[PATCH v3 08/12] Serial: OMAP2+: Make the RX_TIMEOUT for DMA configurable for each UART

Kevin Hilman khilman at ti.com
Fri Jun 24 20:16:47 EDT 2011

"Govindraj.R" <govindraj.raja at ti.com> writes:

> From: Jon Hunter <jon-hunter at ti.com>
> When using DMA there are two timeouts defined. The first timeout,
> rx_timeout, is really a polling rate in which software polls the
> DMA status to see if the DMA has finished. This is necessary for
> the RX side because we do not know how much data we will receive.
> The secound timeout, RX_TIMEOUT, is a timeout after which the
> DMA will be stopped if no more data is received. To make this
> clearer, rename rx_timeout as rx_poll_rate and rename the
> function serial_omap_rx_timeout() to serial_omap_rxdma_poll().
> The OMAP-Serial driver defines an RX_TIMEOUT of 3 seconds that is
> used to indicate when the DMA for UART can be stopped if no more
> data is received. The value is a global definition that is applied
> to all instances of the UART.
> Each UART may be used for a different purpose and so the timeout
> required may differ. Make this value configurable for each UART so
> that this value can be optimised for power savings.
> Signed-off-by: Jon Hunter <jon-hunter at ti.com>
> Signed-off-by: Govindraj.R <govindraj.raja at ti.com>

Acked-by: Kevin Hilman <khilman at ti.com>

Jon, thanks (again) for the well-written, descriptive changelog.


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