Commit 0727702a authored by Joachim Fenkes's avatar Joachim Fenkes Committed by Paul Mackerras
Browse files

[POWERPC] ibmebus: change probe/remove interface from using loc-code to DT path 



In some cases, multiple OFDT nodes might share the same location code, so
the location code is not a unique identifier for an OFDT node. Changed the
ibmebus probe/remove interface to use the DT path of the device node instead
of the location code.

The DT path must be written into probe/remove right as it would appear in
the "devspec" attribute of the ebus device: relative to the DT root, with a
leading slash and without a trailing slash. One trailing newline will not
hurt; multiple newlines will (like perl's chomp()).

Example:

 Add a device "/proc/device-tree/foo@12345678" to ibmebus like this:
    echo /foo@12345678 > /sys/bus/ibmebus/probe

 Remove the device like this:
    echo /foo@12345678 > /sys/bus/ibmebus/remove

Signed-off-by: default avatarJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent 370a908d

arch/powerpc/kernel/ibmebus.c

+60 −55
Original line number Diff line number Diff line
@@ -44,8 +44,6 @@ 
#include <asm/ibmebus.h>

#include <asm/abs_addr.h>



#define MAX_LOC_CODE_LENGTH 80



static struct device ibmebus_bus_device = { /* fake "parent" device */

	.bus_id = "ibmebus",

};
@@ -253,7 +251,7 @@ static void ibmebus_add_devices_by_id(struct of_device_id *idt) 
	return;

}



static int ibmebus_match_helper_name(struct device *dev, void *data)

static int ibmebus_match_name(struct device *dev, void *data)

{

	const struct ibmebus_dev *ebus_dev = to_ibmebus_dev(dev);

	const char *name;
@@ -280,7 +278,7 @@ static void ibmebus_remove_devices_by_id(struct of_device_id *idt) 
	while (strlen(idt->name) > 0) {

		while ((dev = bus_find_device(&ibmebus_bus_type, NULL,

					      (void*)idt->name,

					      ibmebus_match_helper_name))) {

					      ibmebus_match_name))) {

			ibmebus_unregister_device(dev);

		}

		idt++;
@@ -371,17 +369,30 @@ static struct device_attribute ibmebus_dev_attrs[] = { 
	__ATTR_NULL

};



static int ibmebus_match_helper_loc_code(struct device *dev, void *data)

static int ibmebus_match_path(struct device *dev, void *data)

{

	const struct ibmebus_dev *ebus_dev = to_ibmebus_dev(dev);

	const char *loc_code;

	int rc;

	struct device_node *dn =

		of_node_get(to_ibmebus_dev(dev)->ofdev.node);



	loc_code = of_get_property(ebus_dev->ofdev.node, "ibm,loc-code", NULL);

	rc = (dn->full_name && (strcasecmp((char*)data, dn->full_name) == 0));



	if (loc_code && (strcmp(data, loc_code) == 0))

		return 1;

	of_node_put(dn);

	return rc;

}



	return 0;

static char *ibmebus_chomp(const char *in, size_t count)

{

	char *out = (char*)kmalloc(count + 1, GFP_KERNEL);

	if (!out)

		return NULL;



	memcpy(out, in, count);

	out[count] = '\0';

	if (out[count - 1] == '\n')

		out[count - 1] = '\0';



	return out;

}



static ssize_t ibmebus_store_probe(struct bus_type *bus,
@@ -389,65 +400,59 @@ static ssize_t ibmebus_store_probe(struct bus_type *bus, 
{

	struct device_node *dn = NULL;

	struct ibmebus_dev *dev;

	const char *loc_code;

	char parm[MAX_LOC_CODE_LENGTH];

	char *path;

	ssize_t rc;



	if (count >= MAX_LOC_CODE_LENGTH)

		return -EINVAL;

	memcpy(parm, buf, count);

	parm[count] = '\0';

	if (parm[count-1] == '\n')

		parm[count-1] = '\0';



	if (bus_find_device(&ibmebus_bus_type, NULL, parm,

			     ibmebus_match_helper_loc_code)) {

		printk(KERN_WARNING "%s: loc_code %s has already been probed\n",

		       __FUNCTION__, parm);

		return -EINVAL;

	path = ibmebus_chomp(buf, count);

	if (!path)

		return -ENOMEM;



	if (bus_find_device(&ibmebus_bus_type, NULL, path,

			     ibmebus_match_path)) {

		printk(KERN_WARNING "%s: %s has already been probed\n",

		       __FUNCTION__, path);

		rc = -EINVAL;

		goto out;

	}



	while ((dn = of_find_all_nodes(dn))) {

		loc_code = of_get_property(dn, "ibm,loc-code", NULL);

		if (loc_code && (strncmp(loc_code, parm, count) == 0)) {

	if ((dn = of_find_node_by_path(path))) {

		dev = ibmebus_register_device_node(dn);

			if (IS_ERR(dev)) {

		of_node_put(dn);

				return PTR_ERR(dev);

			} else

				return count; /* success */

		}

		rc = IS_ERR(dev) ? PTR_ERR(dev) : count;

	} else {

		printk(KERN_WARNING "%s: no such device node: %s\n",

		       __FUNCTION__, path);

		rc = -ENODEV;

	}



	/* if we drop out of the loop, the loc code was invalid */

	printk(KERN_WARNING "%s: no device with loc_code %s found\n",

	       __FUNCTION__, parm);

	return -ENODEV;

out:

	kfree(path);

	return rc;

}



static ssize_t ibmebus_store_remove(struct bus_type *bus,

				    const char *buf, size_t count)

{

	struct device *dev;

	char parm[MAX_LOC_CODE_LENGTH];

	char *path;



	if (count >= MAX_LOC_CODE_LENGTH)

		return -EINVAL;

	memcpy(parm, buf, count);

	parm[count] = '\0';

	if (parm[count-1] == '\n')

		parm[count-1] = '\0';



	/* The location code is unique, so we will find one device at most */

	if ((dev = bus_find_device(&ibmebus_bus_type, NULL, parm,

				   ibmebus_match_helper_loc_code))) {

	path = ibmebus_chomp(buf, count);

	if (!path)

		return -ENOMEM;



	if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,

				   ibmebus_match_path))) {

		ibmebus_unregister_device(dev);



		kfree(path);

		return count;

	} else {

		printk(KERN_WARNING "%s: loc_code %s not on the bus\n",

		       __FUNCTION__, parm);

		printk(KERN_WARNING "%s: %s not on the bus\n",

		       __FUNCTION__, path);



		kfree(path);

		return -ENODEV;

	}



	return count;

}



static struct bus_attribute ibmebus_bus_attrs[] = {

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