spi: add support for device table matching

With this patch spi drivers can use standard spi_driver.id_table and
MODULE_DEVICE_TABLE() mechanisms to bind against the devices.  Just like
we do with I2C drivers.

This is useful when a single driver supports several variants of devices
but it is not possible to detect them in run-time (like non-JEDEC chips
probing in drivers/mtd/devices/m25p80.c), and when platform_data usage is
overkill.

This patch also makes life a lot easier on OpenFirmware platforms, since
with OF we extensively use proper device IDs in modaliases.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 2 deletions

diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index eb25cedb995..e2051f39f6a 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -20,6 +20,7 @@
 #define __LINUX_SPI_H
 
 #include <linux/device.h>
+#include <linux/mod_devicetable.h>
 
 /*
  * INTERFACES between SPI master-side drivers and SPI infrastructure.
@@ -86,7 +87,7 @@ struct spi_device {
         int                     irq;
         void                    *controller_state;
         void                    *controller_data;
-        char                    modalias[32];
+        char                    modalias[SPI_NAME_SIZE];
 
         /*
          * likely need more hooks for more protocol options affecting how
@@ -145,6 +146,7 @@ struct spi_message;
 
 /**
  * struct spi_driver - Host side "protocol" driver
+ * @id_table: List of SPI devices supported by this driver
  * @probe: Binds this driver to the spi device.  Drivers can verify
  *      that the device is actually present, and may need to configure
  *      characteristics (such as bits_per_word) which weren't needed for
@@ -170,6 +172,7 @@ struct spi_message;
  * MMC, RTC, filesystem character device nodes, and hardware monitoring.
  */
 struct spi_driver {
+        const struct spi_device_id *id_table;
         int                     (*probe)(struct spi_device *spi);
         int                     (*remove)(struct spi_device *spi);
         void                    (*shutdown)(struct spi_device *spi);
@@ -734,7 +737,7 @@ struct spi_board_info {
          * controller_data goes to spi_device.controller_data,
          * irq is copied too
          */
-        char            modalias[32];
+        char            modalias[SPI_NAME_SIZE];
         const void      *platform_data;
         void            *controller_data;
         int             irq;
@@ -802,4 +805,7 @@ spi_unregister_device(struct spi_device *spi)
                 device_unregister(&spi->dev);
 }
 
+extern const struct spi_device_id *
+spi_get_device_id(const struct spi_device *sdev);
+
 #endif /* __LINUX_SPI_H */