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-rw-r--r--Documentation/spi/spi-summary13
1 files changed, 13 insertions, 0 deletions
diff --git a/Documentation/spi/spi-summary b/Documentation/spi/spi-summary
index 761debf748e9..a5ffba33a351 100644
--- a/Documentation/spi/spi-summary
+++ b/Documentation/spi/spi-summary
@@ -115,6 +115,9 @@ shows up in sysfs in several locations:
/sys/devices/.../CTLR/spiB.C ... spi_device for on bus "B",
chipselect C, accessed through CTLR.
+ /sys/devices/.../CTLR/spiB.C/modalias ... identifies the driver
+ that should be used with this device (for hotplug/coldplug)
+
/sys/bus/spi/devices/spiB.C ... symlink to the physical
spiB-C device
@@ -247,6 +250,12 @@ driver is registered:
Like with other static board-specific setup, you won't unregister those.
+The widely used "card" style computers bundle memory, cpu, and little else
+onto a card that's maybe just thirty square centimeters. On such systems,
+your arch/.../mach-.../board-*.c file would primarily provide information
+about the devices on the mainboard into which such a card is plugged. That
+certainly includes SPI devices hooked up through the card connectors!
+
NON-STATIC CONFIGURATIONS
@@ -258,6 +267,10 @@ up the spi bus master, and will likely need spi_new_device() to provide the
board info based on the board that was hotplugged. Of course, you'd later
call at least spi_unregister_device() when that board is removed.
+When Linux includes support for MMC/SD/SDIO/DataFlash cards through SPI, those
+configurations will also be dynamic. Fortunately, those devices all support
+basic device identification probes, so that support should hotplug normally.
+
How do I write an "SPI Protocol Driver"?
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