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Diffstat (limited to 'libsysfs/sysfs_device.c')
-rw-r--r--libsysfs/sysfs_device.c269
1 files changed, 134 insertions, 135 deletions
diff --git a/libsysfs/sysfs_device.c b/libsysfs/sysfs_device.c
index 89704dcd80..fbd046f229 100644
--- a/libsysfs/sysfs_device.c
+++ b/libsysfs/sysfs_device.c
@@ -23,6 +23,77 @@
#include "libsysfs.h"
#include "sysfs.h"
+static int confirm_device_bus(struct sysfs_device *dev,
+ unsigned char *busname, unsigned char *bus_id)
+{
+ struct sysfs_link *devlink = NULL;
+ unsigned char devpath[SYSFS_PATH_MAX];
+ int result = 0;
+
+ if (busname == NULL || bus_id == NULL)
+ return -1;
+
+ if (sysfs_get_mnt_path(devpath, SYSFS_PATH_MAX) != 0)
+ return -1;
+
+ strcat(devpath, SYSFS_BUS_DIR);
+ strcat(devpath, "/");
+ strcat(devpath, busname);
+ strcat(devpath, SYSFS_DEVICES_DIR);
+ strcat(devpath, "/");
+ strcat(devpath, bus_id);
+
+ devlink = sysfs_open_link(devpath);
+ if (devlink == NULL)
+ return -1;
+
+ if (strcmp(devlink->target, dev->path) == 0)
+ result++;
+ sysfs_close_link(devlink);
+ return result;
+}
+
+/**
+ * get_device_bus: retrieves the bus name the device is on, checks path to
+ * bus' link to make sure it has correct device.
+ * @dev: device to get busname.
+ * returns 0 with success and -1 with error.
+ */
+static int get_device_bus(struct sysfs_device *dev)
+{
+ unsigned char subsys[SYSFS_NAME_LEN], *bus = NULL, *curdev = NULL;
+ struct dlist *buslist = NULL, *device_list = NULL;
+
+ if (dev == NULL) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ strcpy(subsys, SYSFS_BUS_DIR); /* subsys = /bus */
+ buslist = sysfs_open_subsystem_list(subsys);
+ if (buslist != NULL) {
+ dlist_for_each_data(buslist, bus, char) {
+ device_list = sysfs_open_bus_devices_list(bus);
+ if (device_list != NULL) {
+ dlist_for_each_data(device_list,
+ curdev, char) {
+ if (strcmp(dev->bus_id, curdev) == 0
+ && confirm_device_bus(dev, bus,
+ curdev) > 0) {
+ strcpy(dev->bus, bus);
+ sysfs_close_list(device_list);
+ sysfs_close_list(buslist);
+ return 0;
+ }
+ }
+ sysfs_close_list(device_list);
+ }
+ }
+ sysfs_close_list(buslist);
+ }
+ return -1;
+}
+
/**
* sysfs_close_device_tree: closes every device in the supplied tree,
* closing children only.
@@ -150,6 +221,9 @@ struct sysfs_device *sysfs_open_device(const unsigned char *path)
* implies that the dev->name and dev->bus_id contain same data.
*/
strncpy(dev->name, sdir->name, SYSFS_NAME_LEN);
+
+ if (get_device_bus(dev) != 0)
+ strcpy(dev->bus, SYSFS_UNKNOWN);
return dev;
}
@@ -339,55 +413,6 @@ struct dlist *sysfs_get_device_attributes(struct sysfs_device *device)
}
/**
- * sysfs_open_device_by_id: open a device by id (use the "bus" subsystem)
- * @bus_id: bus_id of the device to open - has to be the "bus_id" in
- * /sys/bus/xxx/devices
- * @bus: bus the device belongs to
- * @bsize: size of the bus buffer
- * returns struct sysfs_device if found, NULL otherwise
- * NOTE:
- * 1. Use sysfs_close_device to close the device
- * 2. Bus the device is on must be supplied
- * Use sysfs_find_device_bus to get the bus name
- */
-struct sysfs_device *sysfs_open_device_by_id(const unsigned char *bus_id,
- const unsigned char *bus, size_t bsize)
-{
- char sysfs_path[SYSFS_PATH_MAX], device_path[SYSFS_PATH_MAX];
- struct sysfs_device *device = NULL;
-
- if (bus_id == NULL || bus == NULL) {
- errno = EINVAL;
- return NULL;
- }
- memset(sysfs_path, 0, SYSFS_PATH_MAX);
- if ((sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX)) != 0) {
- dprintf("Error getting sysfs mount path\n");
- return NULL;
- }
- strcat(sysfs_path, SYSFS_BUS_DIR);
- strcat(sysfs_path, "/");
- strncat(sysfs_path, bus, bsize);
- strcat(sysfs_path, SYSFS_DEVICES_DIR);
- strcat(sysfs_path, "/");
- strcat(sysfs_path, bus_id);
-
- /* devices under /sys/bus/xxx/devices are links to devices subsystem */
- if ((sysfs_get_link(sysfs_path, device_path, SYSFS_PATH_MAX)) < 0) {
- dprintf("Error getting device path\n");
- return NULL;
- }
-
- device = sysfs_open_device(device_path);
- if (device == NULL) {
- dprintf("Error opening device %s\n", bus_id);
- return NULL;
- }
-
- return device;
-}
-
-/**
* get_device_absolute_path: looks up the bus the device is on, gets
* absolute path to the device
* @device: device for which path is needed
@@ -395,29 +420,24 @@ struct sysfs_device *sysfs_open_device_by_id(const unsigned char *bus_id,
* @psize: size of "path"
* Returns 0 on success -1 on failure
*/
-static int get_device_absolute_path(const unsigned char *device,
- unsigned char *path, size_t psize)
+static int get_device_absolute_path(const unsigned char *device,
+ const unsigned char *bus, unsigned char *path, size_t psize)
{
- unsigned char bus_name[SYSFS_NAME_LEN], bus_path[SYSFS_PATH_MAX];
+ unsigned char bus_path[SYSFS_NAME_LEN];
if (device == NULL || path == NULL) {
errno = EINVAL;
return -1;
}
- memset(bus_name, 0, SYSFS_NAME_LEN);
memset(bus_path, 0, SYSFS_NAME_LEN);
- if ((sysfs_find_device_bus(device, bus_name, SYSFS_NAME_LEN)) != 0) {
- dprintf("Device %s not found\n", device);
- return -1;
- }
if (sysfs_get_mnt_path(bus_path, SYSFS_PATH_MAX) != 0) {
dprintf ("Sysfs not supported on this system\n");
return -1;
}
strcat(bus_path, SYSFS_BUS_DIR);
strcat(bus_path, "/");
- strcat(bus_path, bus_name);
+ strcat(bus_path, bus);
strcat(bus_path, SYSFS_DEVICES_DIR);
strcat(bus_path, "/");
strcat(bus_path, device);
@@ -433,106 +453,85 @@ static int get_device_absolute_path(const unsigned char *device,
}
/**
- * sysfs_write_device_attr: modify a "writable" attribute for the given device
- * @dev: device bus_id for which attribute has to be changed
- * @attrib: attribute to change
- * @value: value to change to
- * @len: "value" length to write
- * Returns 0 on success -1 on error
- */
-int sysfs_write_device_attr(unsigned char *dev, unsigned char *attrib,
- unsigned char *value, size_t len)
+ * sysfs_open_device_by_id: open a device by id (use the "bus" subsystem)
+ * @bus_id: bus_id of the device to open - has to be the "bus_id" in
+ * /sys/bus/xxx/devices
+ * @bus: bus the device belongs to
+ * @bsize: size of the bus buffer
+ * returns struct sysfs_device if found, NULL otherwise
+ * NOTE:
+ * 1. Use sysfs_close_device to close the device
+ * 2. Bus the device is on must be supplied
+ * Use sysfs_find_device_bus to get the bus name
+ */
+struct sysfs_device *sysfs_open_device_by_id(const unsigned char *bus_id,
+ const unsigned char *bus, size_t bsize)
{
- struct sysfs_attribute *attribute = NULL;
- unsigned char devpath[SYSFS_PATH_MAX];
+ char sysfs_path[SYSFS_PATH_MAX];
+ struct sysfs_device *device = NULL;
- if (dev == NULL || attrib == NULL || value == NULL) {
+ if (bus_id == NULL || bus == NULL) {
errno = EINVAL;
- return -1;
- }
-
- memset(devpath, 0, SYSFS_PATH_MAX);
- if ((get_device_absolute_path(dev, devpath, SYSFS_PATH_MAX)) != 0) {
- dprintf("Error finding absolute path to device %s\n", dev);
- return -1;
- }
- strcat(devpath, "/");
- strcat(devpath, attrib);
- attribute = sysfs_open_attribute(devpath);
- if (attribute == NULL) {
- dprintf("Attribute %s could not be retrieved for device %s\n",
- attrib, dev);
- return -1;
+ return NULL;
}
- if (attribute->method & SYSFS_METHOD_SHOW) {
- if ((sysfs_read_attribute(attribute)) != 0) {
- dprintf("Error reading attribute %s for device %s\n",
- attrib, dev);
- sysfs_close_attribute(attribute);
- return -1;
- }
+ memset(sysfs_path, 0, SYSFS_PATH_MAX);
+ if ((get_device_absolute_path(bus_id, bus, sysfs_path,
+ SYSFS_PATH_MAX)) != 0) {
+ dprintf("Error getting to device %s\n", bus_id);
+ return NULL;
}
- if ((sysfs_write_attribute(attribute, value, len)) < 0) {
- dprintf("Error setting %s to %s\n", attrib, value);
- sysfs_close_attribute(attribute);
- return -1;
+
+ device = sysfs_open_device(sysfs_path);
+ if (device == NULL) {
+ dprintf("Error opening device %s\n", bus_id);
+ return NULL;
}
- sysfs_close_attribute(attribute);
- return 0;
+
+ return device;
}
-/**
- * sysfs_read_device_attr: read an attribute of the given device
- * @dev: device bus_id for which attribute has to be changed
- * @attrib: attribute to read
- * @value: buffer to return value in
- * @len: size of buffer available
- * Returns 0 on success -1 on error
- */
-int sysfs_read_device_attr(unsigned char *dev, unsigned char *attrib,
- unsigned char *value, size_t len)
+/*
+ * sysfs_open_device_attr: open the given device's attribute
+ * @bus: Bus on which to look
+ * @dev_id: device for which attribute is required
+ * @attrname: name of the attribute to look for
+ * Returns struct sysfs_attribute on success and NULL on failure
+ *
+ * NOTE:
+ * A call to sysfs_close_attribute() is required to close
+ * the attribute returned and free memory.
+ */
+struct sysfs_attribute *sysfs_open_device_attr(const unsigned char *bus,
+ const unsigned char *bus_id, const unsigned char *attrib)
{
struct sysfs_attribute *attribute = NULL;
unsigned char devpath[SYSFS_PATH_MAX];
-
- if (dev == NULL || attrib == NULL || value == NULL) {
+
+ if (bus == NULL || bus_id == NULL || attrib == NULL) {
errno = EINVAL;
- return -1;
+ return NULL;
}
-
+
memset(devpath, 0, SYSFS_PATH_MAX);
- if ((get_device_absolute_path(dev, devpath, SYSFS_PATH_MAX)) != 0) {
- dprintf("Error finding absolute path to device %s\n", dev);
- return -1;
+ if ((get_device_absolute_path(bus_id, bus, devpath,
+ SYSFS_PATH_MAX)) != 0) {
+ dprintf("Error getting to device %s\n", bus_id);
+ return NULL;
}
strcat(devpath, "/");
strcat(devpath, attrib);
attribute = sysfs_open_attribute(devpath);
if (attribute == NULL) {
dprintf("Error opening attribute %s for device %s\n",
- attrib, dev);
- return -1;
- }
- if (!(attribute->method & SYSFS_METHOD_SHOW)) {
- dprintf("Show method not supported for attribute %s\n",
- attrib);
- sysfs_close_attribute(attribute);
- return -1;
+ attrib, bus_id);
+ return NULL;
}
if ((sysfs_read_attribute(attribute)) != 0) {
dprintf("Error reading attribute %s for device %s\n",
- attrib, dev);
+ attrib, bus_id);
sysfs_close_attribute(attribute);
- return -1;
- }
- if (attribute->len > len) {
- dprintf("Value length %d is larger than supplied buffer %d\n",
- attribute->len, len);
- sysfs_close_attribute(attribute);
- return -1;
+ return NULL;
}
- strncpy(value, attribute->value, attribute->len);
- value[(attribute->len)+1] = 0;
- sysfs_close_attribute(attribute);
- return 0;
+ return attribute;
}
+