+/* modalias support enables more hands-off userspace setup:
+ * (a) environment variable lets new-style hotplug events work once system is
+ * fully running: "modprobe $MODALIAS"
+ * (b) sysfs attribute lets new-style coldplug recover from hotplug events
+ * mishandled before system is fully running: "modprobe $(cat modalias)"
+ */
+static ssize_t
+modalias_show(struct device *dev, struct device_attribute *a, char *buf)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ int len = snprintf(buf, PAGE_SIZE, "%s\n", pdev->name);
+
+ return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
+}
+
+static struct device_attribute platform_dev_attrs[] = {
+ __ATTR_RO(modalias),
+ __ATTR_NULL,
+};
+
+static int platform_uevent(struct device *dev, char **envp, int num_envp,
+ char *buffer, int buffer_size)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+
+ envp[0] = buffer;
+ snprintf(buffer, buffer_size, "MODALIAS=%s", pdev->name);
+ return 0;
+}
+
+