diff options
| author | Mark Brown <broonie@linaro.org> | 2014-01-23 13:07:01 +0000 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2014-01-23 13:07:01 +0000 |
| commit | 3c1039745ef2925aceed53d38af0cddac8e36f31 (patch) | |
| tree | 163fe6bf0ab203d69712936b3bda5d3e98acdeee /Documentation | |
| parent | 7e2c225d585cd6d7481ff4ec446a67334ef11f4d (diff) | |
| parent | 1afd9989a6a2561183be82e420d4d2f3889b7ee7 (diff) | |
Merge remote-tracking branch 'spi/topic/core' into spi-linus
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/spi/spi-summary | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/Documentation/spi/spi-summary b/Documentation/spi/spi-summary index f21edb983413..f72e0d1e0da8 100644 --- a/Documentation/spi/spi-summary +++ b/Documentation/spi/spi-summary @@ -34,7 +34,7 @@ SPI slave functions are usually not interoperable between vendors - It may also be used to stream data in either direction (half duplex), or both of them at the same time (full duplex). - - Some devices may use eight bit words. Others may different word + - Some devices may use eight bit words. Others may use different word lengths, such as streams of 12-bit or 20-bit digital samples. - Words are usually sent with their most significant bit (MSB) first, @@ -121,7 +121,7 @@ active. So the master must set the clock to inactive before selecting a slave, and the slave can tell the chosen polarity by sampling the clock level when its select line goes active. That's why many devices support for example both modes 0 and 3: they don't care about polarity, -and alway clock data in/out on rising clock edges. +and always clock data in/out on rising clock edges. How do these driver programming interfaces work? @@ -139,7 +139,7 @@ a command and then reading its response. There are two types of SPI driver, here called: - Controller drivers ... controllers may be built in to System-On-Chip + Controller drivers ... controllers may be built into System-On-Chip processors, and often support both Master and Slave roles. These drivers touch hardware registers and may use DMA. Or they can be PIO bitbangers, needing just GPIO pins. @@ -548,7 +548,7 @@ SPI MASTER METHODS DEPRECATED METHODS master->transfer(struct spi_device *spi, struct spi_message *message) - This must not sleep. Its responsibility is arrange that the + This must not sleep. Its responsibility is to arrange that the transfer happens and its complete() callback is issued. The two will normally happen later, after other transfers complete, and if the controller is idle it will need to be kickstarted. This |