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-rw-r--r--Documentation/spi/spi-summary8
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
34 - It may also be used to stream data in either direction (half duplex), 34 - It may also be used to stream data in either direction (half duplex),
35 or both of them at the same time (full duplex). 35 or both of them at the same time (full duplex).
36 36
37 - Some devices may use eight bit words. Others may different word 37 - Some devices may use eight bit words. Others may use different word
38 lengths, such as streams of 12-bit or 20-bit digital samples. 38 lengths, such as streams of 12-bit or 20-bit digital samples.
39 39
40 - Words are usually sent with their most significant bit (MSB) first, 40 - 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
121a slave, and the slave can tell the chosen polarity by sampling the 121a slave, and the slave can tell the chosen polarity by sampling the
122clock level when its select line goes active. That's why many devices 122clock level when its select line goes active. That's why many devices
123support for example both modes 0 and 3: they don't care about polarity, 123support for example both modes 0 and 3: they don't care about polarity,
124and alway clock data in/out on rising clock edges. 124and always clock data in/out on rising clock edges.
125 125
126 126
127How do these driver programming interfaces work? 127How do these driver programming interfaces work?
@@ -139,7 +139,7 @@ a command and then reading its response.
139 139
140There are two types of SPI driver, here called: 140There are two types of SPI driver, here called:
141 141
142 Controller drivers ... controllers may be built in to System-On-Chip 142 Controller drivers ... controllers may be built into System-On-Chip
143 processors, and often support both Master and Slave roles. 143 processors, and often support both Master and Slave roles.
144 These drivers touch hardware registers and may use DMA. 144 These drivers touch hardware registers and may use DMA.
145 Or they can be PIO bitbangers, needing just GPIO pins. 145 Or they can be PIO bitbangers, needing just GPIO pins.
@@ -548,7 +548,7 @@ SPI MASTER METHODS
548 DEPRECATED METHODS 548 DEPRECATED METHODS
549 549
550 master->transfer(struct spi_device *spi, struct spi_message *message) 550 master->transfer(struct spi_device *spi, struct spi_message *message)
551 This must not sleep. Its responsibility is arrange that the 551 This must not sleep. Its responsibility is to arrange that the
552 transfer happens and its complete() callback is issued. The two 552 transfer happens and its complete() callback is issued. The two
553 will normally happen later, after other transfers complete, and 553 will normally happen later, after other transfers complete, and
554 if the controller is idle it will need to be kickstarted. This 554 if the controller is idle it will need to be kickstarted. This