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-rw-r--r--Documentation/spi/spi-summary13
-rw-r--r--drivers/mtd/devices/m25p80.c4
-rw-r--r--drivers/mtd/devices/mtd_dataflash.c2
-rw-r--r--drivers/spi/Kconfig10
-rw-r--r--drivers/spi/Makefile1
5 files changed, 28 insertions, 2 deletions
diff --git a/Documentation/spi/spi-summary b/Documentation/spi/spi-summary
index 761debf..a5ffba3 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"?
----------------------------------------
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index 45108ed..d5f2408 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -378,7 +378,9 @@ static int m25p80_write(struct mtd_info *mtd, loff_t to, size_t len,
spi_sync(flash->spi, &m);
- *retlen += m.actual_length - sizeof(flash->command);
+ if (retlen)
+ *retlen += m.actual_length
+ - sizeof(flash->command);
}
}
diff --git a/drivers/mtd/devices/mtd_dataflash.c b/drivers/mtd/devices/mtd_dataflash.c
index 99d3a03..155737e 100644
--- a/drivers/mtd/devices/mtd_dataflash.c
+++ b/drivers/mtd/devices/mtd_dataflash.c
@@ -508,7 +508,7 @@ add_dataflash(struct spi_device *spi, char *name,
priv->partitioned = 1;
return add_mtd_partitions(device, parts, nr_parts);
}
- } else if (pdata->nr_parts)
+ } else if (pdata && pdata->nr_parts)
dev_warn(&spi->dev, "ignoring %d default partitions on %s\n",
pdata->nr_parts, device->name);
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 9b21c5d..7a75fae 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -65,6 +65,16 @@ config SPI_BITBANG
need it. You only need to select this explicitly to support driver
modules that aren't part of this kernel tree.
+config SPI_BUTTERFLY
+ tristate "Parallel port adapter for AVR Butterfly (DEVELOPMENT)"
+ depends on SPI_MASTER && PARPORT && EXPERIMENTAL
+ select SPI_BITBANG
+ help
+ This uses a custom parallel port cable to connect to an AVR
+ Butterfly <http://www.atmel.com/products/avr/butterfly>, an
+ inexpensive battery powered microcontroller evaluation board.
+ This same cable can be used to flash new firmware.
+
#
# Add new SPI master controllers in alphabetical order above this line
#
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 5da6a4d..c2c87e8 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_SPI_MASTER) += spi.o
# SPI master controller drivers (bus)
obj-$(CONFIG_SPI_BITBANG) += spi_bitbang.o
+obj-$(CONFIG_SPI_BUTTERFLY) += spi_butterfly.o
# ... add above this line ...
# SPI protocol drivers (device/link on bus)
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