[POWERPC] Add a unified uevent handler for bus based on of_device

This common uevent handler allow the several bus types based on
of_device to generate the uevent properly and avoiding
code duplication.

This handlers take a struct device as argument and can therefore
be used as the uevent call directly if no special treatment is
needed for the bus.

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 112 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/of_device.c b/arch/powerpc/kernel/of_device.c
index e921514e655..e8aa1f3675b 100644
--- a/arch/powerpc/kernel/of_device.c
+++ b/arch/powerpc/kernel/of_device.c
@@ -120,6 +120,117 @@ void of_device_unregister(struct of_device *ofdev)
 }
 
 
+static ssize_t of_device_get_modalias(struct of_device *ofdev,
+					char *str, ssize_t len)
+{
+	const char *compat;
+	int cplen, i;
+	ssize_t tsize, csize, repend;
+
+	/* Name & Type */
+	csize = snprintf(str, len, "of:N%sT%s",
+				ofdev->node->name, ofdev->node->type);
+
+	/* Get compatible property if any */
+	compat = get_property(ofdev->node, "compatible", &cplen);
+	if (!compat)
+		return csize;
+
+	/* Find true end (we tolerate multiple \0 at the end */
+	for (i=(cplen-1); i>=0 && !compat[i]; i--)
+		cplen--;
+	if (!cplen)
+		return csize;
+	cplen++;
+
+	/* Check space (need cplen+1 chars including final \0) */
+	tsize = csize + cplen;
+	repend = tsize;
+
+	if (csize>=len)		/* @ the limit, all is already filled */
+		return tsize;
+
+	if (tsize>=len) {		/* limit compat list */
+		cplen = len-csize-1;
+		repend = len;
+	}
+
+	/* Copy and do char replacement */
+	memcpy(&str[csize+1], compat, cplen);
+	for (i=csize; i<repend; i++) {
+		char c = str[i];
+		if (c=='\0')
+			str[i] = 'C';
+		else if (c==' ')
+			str[i] = '_';
+	}
+
+	return tsize;
+}
+
+int of_device_uevent(struct device *dev,
+		char **envp, int num_envp, char *buffer, int buffer_size)
+{
+	struct of_device *ofdev;
+	const char *compat;
+	int i = 0, length = 0, seen = 0, cplen, sl;
+
+	if (!dev)
+		return -ENODEV;
+
+	ofdev = to_of_device(dev);
+
+	if (add_uevent_var(envp, num_envp, &i,
+			   buffer, buffer_size, &length,
+			   "OF_NAME=%s", ofdev->node->name))
+		return -ENOMEM;
+
+	if (add_uevent_var(envp, num_envp, &i,
+			   buffer, buffer_size, &length,
+			   "OF_TYPE=%s", ofdev->node->type))
+		return -ENOMEM;
+
+        /* Since the compatible field can contain pretty much anything
+         * it's not really legal to split it out with commas. We split it
+         * up using a number of environment variables instead. */
+
+	compat = get_property(ofdev->node, "compatible", &cplen);
+	while (compat && *compat && cplen > 0) {
+		if (add_uevent_var(envp, num_envp, &i,
+				   buffer, buffer_size, &length,
+				   "OF_COMPATIBLE_%d=%s", seen, compat))
+			return -ENOMEM;
+
+		sl = strlen (compat) + 1;
+		compat += sl;
+		cplen -= sl;
+		seen++;
+	}
+
+	if (add_uevent_var(envp, num_envp, &i,
+			   buffer, buffer_size, &length,
+			   "OF_COMPATIBLE_N=%d", seen))
+		return -ENOMEM;
+
+	/* modalias is trickier, we add it in 2 steps */
+	if (add_uevent_var(envp, num_envp, &i,
+			   buffer, buffer_size, &length,
+			   "MODALIAS="))
+		return -ENOMEM;
+
+	sl = of_device_get_modalias(ofdev, &buffer[length-1],
+					buffer_size-length);
+	if (sl >= (buffer_size-length))
+		return -ENOMEM;
+
+	length += sl;
+
+	envp[i] = NULL;
+
+	return 0;
+}
+
+
 EXPORT_SYMBOL(of_match_node);
 EXPORT_SYMBOL(of_match_device);
 EXPORT_SYMBOL(of_device_register);
@@ -127,3 +238,4 @@ EXPORT_SYMBOL(of_device_unregister);
 EXPORT_SYMBOL(of_dev_get);
 EXPORT_SYMBOL(of_dev_put);
 EXPORT_SYMBOL(of_release_dev);
+EXPORT_SYMBOL(of_device_uevent);