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>
This commit is contained in:
Anton Vorontsov 2009-09-22 16:46:04 -07:00 committed by Linus Torvalds
parent b5f3294f0b
commit 75368bf6c2
4 changed files with 54 additions and 2 deletions

View File

@ -59,9 +59,32 @@ static struct device_attribute spi_dev_attrs[] = {
* and the sysfs version makes coldplug work too.
*/
static const struct spi_device_id *spi_match_id(const struct spi_device_id *id,
const struct spi_device *sdev)
{
while (id->name[0]) {
if (!strcmp(sdev->modalias, id->name))
return id;
id++;
}
return NULL;
}
const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev)
{
const struct spi_driver *sdrv = to_spi_driver(sdev->dev.driver);
return spi_match_id(sdrv->id_table, sdev);
}
EXPORT_SYMBOL_GPL(spi_get_device_id);
static int spi_match_device(struct device *dev, struct device_driver *drv)
{
const struct spi_device *spi = to_spi_device(dev);
const struct spi_driver *sdrv = to_spi_driver(drv);
if (sdrv->id_table)
return !!spi_match_id(sdrv->id_table, spi);
return strcmp(spi->modalias, drv->name) == 0;
}

View File

@ -399,6 +399,16 @@ struct i2c_device_id {
__attribute__((aligned(sizeof(kernel_ulong_t))));
};
/* spi */
#define SPI_NAME_SIZE 32
struct spi_device_id {
char name[SPI_NAME_SIZE];
kernel_ulong_t driver_data /* Data private to the driver */
__attribute__((aligned(sizeof(kernel_ulong_t))));
};
/* dmi */
enum dmi_field {
DMI_NONE,

View File

@ -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 */

View File

@ -657,6 +657,15 @@ static int do_i2c_entry(const char *filename, struct i2c_device_id *id,
return 1;
}
/* Looks like: S */
static int do_spi_entry(const char *filename, struct spi_device_id *id,
char *alias)
{
sprintf(alias, "%s", id->name);
return 1;
}
static const struct dmifield {
const char *prefix;
int field;
@ -853,6 +862,10 @@ void handle_moddevtable(struct module *mod, struct elf_info *info,
do_table(symval, sym->st_size,
sizeof(struct i2c_device_id), "i2c",
do_i2c_entry, mod);
else if (sym_is(symname, "__mod_spi_device_table"))
do_table(symval, sym->st_size,
sizeof(struct spi_device_id), "spi",
do_spi_entry, mod);
else if (sym_is(symname, "__mod_dmi_device_table"))
do_table(symval, sym->st_size,
sizeof(struct dmi_system_id), "dmi",