[PATCH] pcmcia: hotplug event for PCMCIA devices

Export information to /sbin/hotplug for PCMCIA devices: card_id, manf_id,
func_id, bus_id (like pcmcia1.0) and crc32-hashes of the prod_id strings.

Why not the prod_id strings themselves?

a) They may contain all sorts of strange and difficult to handle characters,
   like " ".

b) It's impossible to pass multiple strings to userspace.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 67 insertions, 0 deletions

diff --git a/drivers/pcmcia/ds.c b/drivers/pcmcia/ds.c
index 569e55feecfd..35d479b0df64 100644
--- a/drivers/pcmcia/ds.c
+++ b/drivers/pcmcia/ds.c
@@ -35,6 +35,7 @@
 #include <linux/delay.h>
 #include <linux/kref.h>
 #include <linux/workqueue.h>
+#include <linux/crc32.h>
 
 #include <asm/atomic.h>
 
@@ -601,6 +602,71 @@ static int pcmcia_bus_match(struct device * dev, struct device_driver * drv) {
         return 0;
 }
 
+#ifdef CONFIG_HOTPLUG
+
+static int pcmcia_bus_hotplug(struct device *dev, char **envp, int num_envp,
+                              char *buffer, int buffer_size)
+{
+        struct pcmcia_device *p_dev;
+        int i, length = 0;
+        u32 hash[4] = { 0, 0, 0, 0};
+
+        if (!dev)
+                return -ENODEV;
+
+        p_dev = to_pcmcia_dev(dev);
+
+        /* calculate hashes */
+        for (i=0; i<4; i++) {
+                if (!p_dev->prod_id[i])
+                        continue;
+                hash[i] = crc32(0, p_dev->prod_id[i], strlen(p_dev->prod_id[i]));
+        }
+
+        i = 0;
+
+        if (add_hotplug_env_var(envp, num_envp, &i,
+                                buffer, buffer_size, &length,
+                                "SOCKET_NO=%u",
+                                p_dev->socket->sock))
+                return -ENOMEM;
+
+        if (add_hotplug_env_var(envp, num_envp, &i,
+                                buffer, buffer_size, &length,
+                                "DEVICE_NO=%02X",
+                                p_dev->device_no))
+                return -ENOMEM;
+
+        if (add_hotplug_env_var(envp, num_envp, &i,
+                                buffer, buffer_size, &length,
+                                "MODALIAS=pcmcia:m%04Xc%04Xf%02Xfn%02Xpfn%02X"
+                                "pa%08Xpb%08Xpc%08Xpd%08X",
+                                p_dev->has_manf_id ? p_dev->manf_id : 0,
+                                p_dev->has_card_id ? p_dev->card_id : 0,
+                                p_dev->has_func_id ? p_dev->func_id : 0,
+                                p_dev->func,
+                                p_dev->device_no,
+                                hash[0],
+                                hash[1],
+                                hash[2],
+                                hash[3]))
+                return -ENOMEM;
+
+        envp[i] = NULL;
+
+        return 0;
+}
+
+#else
+
+static int pcmcia_bus_hotplug(struct device *dev, char **envp, int num_envp,
+                              char *buffer, int buffer_size)
+{
+        return -ENODEV;
+}
+
+#endif
+
 /************************ per-device sysfs output ***************************/
 
 #define pcmcia_device_attr(field, test, format)                         \
@@ -1575,6 +1641,7 @@ static struct class_interface pcmcia_bus_interface = {
 
 struct bus_type pcmcia_bus_type = {
         .name = "pcmcia",
+        .hotplug = pcmcia_bus_hotplug,
         .match = pcmcia_bus_match,
         .dev_attrs = pcmcia_dev_attrs,
 };