Commit 2ffe8c5f authored by Grant Likely's avatar Grant Likely
Browse files

of: refactor of_modalias_node() and remove explicit match table. 



This patch tightens up the behaviour of of_modalias_node() to be more
predicatable and to eliminate the explicit of_modalias_tablep[] that
is currently used to override the first entry in the compatible list
of a device.  The override table was needed originally because spi
and i2c drivers had no way to do of-style matching.  Now that all
devices can have an of_node pointer, and all drivers can have an
of_match_table, the explicit override table is no longer needed
because each driver can specify its own OF-style match data.

The mpc8349emitx-mcu driver is modified to explicitly specify the
correct device to bind against.

Signed-off-by: default avatarGrant Likely <grant.likely@secretlab.ca>
parent 959e85f7

arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c

+6 −0
Original line number Diff line number Diff line
@@ -160,10 +160,16 @@ static const struct i2c_device_id mcu_ids[] = { 
};

MODULE_DEVICE_TABLE(i2c, mcu_ids);



static struct of_device_id mcu_of_match_table[] __devinitdata = {

	{ .compatible = "fsl,mcu-mpc8349emitx", },

	{ },

};



static struct i2c_driver mcu_driver = {

	.driver = {

		.name = "mcu-mpc8349emitx",

		.owner = THIS_MODULE,

		.of_match_table = mcu_of_match_table,

	},

	.probe = mcu_probe,

	.remove	= __devexit_p(mcu_remove),

drivers/mmc/host/mmc_spi.c

+8 −0
Original line number Diff line number Diff line
@@ -1533,12 +1533,20 @@ static int __devexit mmc_spi_remove(struct spi_device *spi) 
	return 0;

}



#if defined(CONFIG_OF)

static struct of_device_id mmc_spi_of_match_table[] __devinitdata = {

	{ .compatible = "mmc-spi-slot", },

};

#endif



static struct spi_driver mmc_spi_driver = {

	.driver = {

		.name =		"mmc_spi",

		.bus =		&spi_bus_type,

		.owner =	THIS_MODULE,

#if defined(CONFIG_OF)

		.of_match_table = mmc_spi_of_match_table,

#endif

	},

	.probe =	mmc_spi_probe,

	.remove =	__devexit_p(mmc_spi_remove),

drivers/of/base.c

+9 −55
Original line number Diff line number Diff line
@@ -544,75 +544,29 @@ struct device_node *of_find_matching_node(struct device_node *from, 
}

EXPORT_SYMBOL(of_find_matching_node);



/**

 * of_modalias_table: Table of explicit compatible ==> modalias mappings

 *

 * This table allows particulare compatible property values to be mapped

 * to modalias strings.  This is useful for busses which do not directly

 * understand the OF device tree but are populated based on data contained

 * within the device tree.  SPI and I2C are the two current users of this

 * table.

 *

 * In most cases, devices do not need to be listed in this table because

 * the modalias value can be derived directly from the compatible table.

 * However, if for any reason a value cannot be derived, then this table

 * provides a method to override the implicit derivation.

 *

 * At the moment, a single table is used for all bus types because it is

 * assumed that the data size is small and that the compatible values

 * should already be distinct enough to differentiate between SPI, I2C

 * and other devices.

 */

struct of_modalias_table {

	char *of_device;

	char *modalias;

};

static struct of_modalias_table of_modalias_table[] = {

	{ "fsl,mcu-mpc8349emitx", "mcu-mpc8349emitx" },

	{ "mmc-spi-slot", "mmc_spi" },

};



/**

 * of_modalias_node - Lookup appropriate modalias for a device node

 * @node:	pointer to a device tree node

 * @modalias:	Pointer to buffer that modalias value will be copied into

 * @len:	Length of modalias value

 *

 * Based on the value of the compatible property, this routine will determine

 * an appropriate modalias value for a particular device tree node.  Two

 * separate methods are attempted to derive a modalias value.

 * Based on the value of the compatible property, this routine will attempt

 * to choose an appropriate modalias value for a particular device tree node.

 * It does this by stripping the manufacturer prefix (as delimited by a ',')

 * from the first entry in the compatible list property.

 *

 * First method is to lookup the compatible value in of_modalias_table.

 * Second is to strip off the manufacturer prefix from the first

 * compatible entry and use the remainder as modalias

 *

 * This routine returns 0 on success

 * This routine returns 0 on success, <0 on failure.

 */

int of_modalias_node(struct device_node *node, char *modalias, int len)

{

	int i, cplen;

	const char *compatible;

	const char *p;



	/* 1. search for exception list entry */

	for (i = 0; i < ARRAY_SIZE(of_modalias_table); i++) {

		compatible = of_modalias_table[i].of_device;

		if (!of_device_is_compatible(node, compatible))

			continue;

		strlcpy(modalias, of_modalias_table[i].modalias, len);

		return 0;

	}

	const char *compatible, *p;

	int cplen;



	compatible = of_get_property(node, "compatible", &cplen);

	if (!compatible)

	if (!compatible || strlen(compatible) > cplen)

		return -ENODEV;



	/* 2. take first compatible entry and strip manufacturer */

	p = strchr(compatible, ',');

	if (!p)

		return -ENODEV;

	p++;

	strlcpy(modalias, p, len);

	strlcpy(modalias, p ? p + 1 : compatible, len);

	return 0;

}

EXPORT_SYMBOL_GPL(of_modalias_node);

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