From 18cc0adb132b390d026c574deec29bf182aede51 Mon Sep 17 00:00:00 2001 From: Baruch Siach Date: Sat, 25 Jan 2014 22:36:14 +0200 Subject: spi: document the transfer_one spi_master callback Signed-off-by: Baruch Siach Signed-off-by: Mark Brown --- Documentation/spi/spi-summary | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'Documentation/spi') diff --git a/Documentation/spi/spi-summary b/Documentation/spi/spi-summary index f72e0d1e0da8..dcaad476789c 100644 --- a/Documentation/spi/spi-summary +++ b/Documentation/spi/spi-summary @@ -545,6 +545,21 @@ SPI MASTER METHODS spi_finalize_current_message() so the subsystem can issue the next transfer. This may sleep. + master->transfer_one(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *transfer) + The subsystem calls the driver to transfer a single transfer while + queuing transfers that arrive in the meantime. When the driver is + finished with this transfer, it must call + spi_finalize_current_transfer() so the subsystem can issue the next + transfer. This may sleep. Note: transfer_one and transfer_one_message + are mutually exclusive; when both are set, the generic subsystem does + not call your transfer_one callback. + + Return values: + negative errno: error + 0: transfer is finished + 1: transfer is still in progress + DEPRECATED METHODS master->transfer(struct spi_device *spi, struct spi_message *message) -- cgit v1.2.3