Re: [BK PATCH] More USB changes for 2.5.38

Greg KH
2002-09-27T19:41:48Z

# ChangeSet 1.611.1.7 -> 1.611.1.8
# drivers/base/core.c 1.39 -> 1.40
# drivers/base/Makefile 1.13 -> 1.14
# drivers/base/base.h 1.12 -> 1.13
# include/linux/device.h 1.38 -> 1.39
# (new) -> 1.1 drivers/base/hotplug.c
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 02/09/27 greg@kroah.com 1.611.1.8
# add hotplug support to the driver core for devices, if their bus type supports it.
# --------------------------------------------
#
diff -Nru a/drivers/base/Makefile b/drivers/base/Makefile
--- a/drivers/base/Makefile Fri Sep 27 12:30:08 2002
+++ b/drivers/base/Makefile Fri Sep 27 12:30:08 2002
@@ -6,6 +6,8 @@

obj-y += fs/

+obj-$(CONFIG_HOTPLUG) += hotplug.o
+
export-objs := core.o power.o sys.o bus.o driver.o \
class.o intf.o platform.o cpu.o

diff -Nru a/drivers/base/base.h b/drivers/base/base.h
--- a/drivers/base/base.h Fri Sep 27 12:30:08 2002
+++ b/drivers/base/base.h Fri Sep 27 12:30:08 2002
@@ -50,3 +50,13 @@

extern int driver_attach(struct device_driver * drv);
extern void driver_detach(struct device_driver * drv);
+
+#ifdef CONFIG_HOTPLUG
+extern int dev_hotplug(struct device *dev, const char *action);
+#else
+static inline int dev_hotplug(struct device *dev, const char *action)
+{
+ return 0;
+}
+#endif
+
diff -Nru a/drivers/base/core.c b/drivers/base/core.c
--- a/drivers/base/core.c Fri Sep 27 12:30:08 2002
+++ b/drivers/base/core.c Fri Sep 27 12:30:08 2002
@@ -200,6 +200,9 @@
if (platform_notify)
platform_notify(dev);

+ /* notify userspace of device entry */
+ dev_hotplug(dev, "add");
+
register_done:
if (error) {
spin_lock(&device_lock);
@@ -254,6 +257,9 @@
*/
if (platform_notify_remove)
platform_notify_remove(dev);
+
+ /* notify userspace that this device is about to disappear */
+ dev_hotplug (dev, "remove");

device_detach(dev);
bus_remove_device(dev);
diff -Nru a/drivers/base/hotplug.c b/drivers/base/hotplug.c
--- /dev/null Wed Dec 31 16:00:00 1969
+++ b/drivers/base/hotplug.c Fri Sep 27 12:30:08 2002
@@ -0,0 +1,103 @@
+/*
+ * drivers/base/hotplug.c - hotplug call code
+ *
+ * Copyright (c) 2000-2001 David Brownell
+ * Copyright (c) 2002 Greg Kroah-Hartman
+ * Copyright (c) 2002 IBM Corp.
+ *
+ * Based off of drivers/usb/core/usb.c:call_agent(), which was
+ * written by David Brownell.
+ *
+ */
+
+#define DEBUG 0
+
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/kmod.h>
+#include <linux/interrupt.h>
+#include "base.h"
+
+/*
+ * hotplugging invokes what /proc/sys/kernel/hotplug says (normally
+ * /sbin/hotplug) when devices get added or removed.
+ *
+ * This invokes a user mode policy agent, typically helping to load driver
+ * or other modules, configure the device, and more. Drivers can provide
+ * a MODULE_DEVICE_TABLE to help with module loading subtasks.
+ */
+#define BUFFER_SIZE 1024 /* should be enough memory for the env */
+#define NUM_ENVP 32 /* number of env pointers */
+int dev_hotplug (struct device *dev, const char *action)
+{
+ char *argv [3], **envp, *buffer, *scratch;
+ int retval;
+ int i = 0;
+
+ pr_debug ("%s\n", __FUNCTION__);
+ if (!dev)
+ return -ENODEV;
+
+ if (!dev->bus || !dev->bus->hotplug)
+ return -ENODEV;
+
+ if (!hotplug_path [0])
+ return -ENODEV;
+
+ if (in_interrupt ()) {
+ pr_debug ("%s - in_interrupt, not allowed!", __FUNCTION__);
+ return -EIO;
+ }
+
+ if (!current->fs->root) {
+ /* don't try to do anything unless we have a root partition */
+ pr_debug ("%s - %s -- no FS yet\n", __FUNCTION__, action);
+ return -EIO;
+ }
+
+ envp = (char **) kmalloc (NUM_ENVP * sizeof (char *), GFP_KERNEL);
+ if (!envp)
+ return -ENOMEM;
+
+ buffer = kmalloc (BUFFER_SIZE, GFP_KERNEL);
+ if (!buffer) {
+ kfree (envp);
+ return -ENOMEM;
+ }
+
+ /* only one standardized param to hotplug command: the bus name */
+ argv [0] = hotplug_path;
+ argv [1] = dev->bus->name;
+ argv [2] = 0;
+
+ /* minimal command environment */
+ envp [i++] = "HOME=/";
+ envp [i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
+
+ scratch = buffer;
+
+ /* action: add, remove */
+ envp [i++] = scratch;
+ scratch += sprintf (scratch, "ACTION=%s", action) + 1;
+
+ /* have the bus specific function set up the rest of the environment */
+ retval = dev->bus->hotplug (dev, &envp[i], NUM_ENVP - i,
+ scratch, BUFFER_SIZE - (scratch - buffer));
+ if (retval) {
+ pr_debug ("%s - hotplug() returned %d\n", __FUNCTION__, retval);
+ goto exit;
+ }
+
+ pr_debug ("%s: %s %s %s %s %s %s\n", __FUNCTION__, argv [0], argv[1],
+ action, envp[0], envp[1], envp[2]);
+ retval = call_usermodehelper (argv [0], argv, envp);
+ if (retval)
+ pr_debug ("%s - call_usermodehelper returned %d\n",
+ __FUNCTION__, retval);
+
+exit:
+ kfree (buffer);
+ kfree (envp);
+ return retval;
+}
diff -Nru a/include/linux/device.h b/include/linux/device.h
--- a/include/linux/device.h Fri Sep 27 12:30:08 2002
+++ b/include/linux/device.h Fri Sep 27 12:30:08 2002
@@ -67,6 +67,8 @@

int (*match)(struct device * dev, struct device_driver * drv);
struct device * (*add) (struct device * parent, char * bus_id);
+ int (*hotplug) (struct device *dev, char **envp,
+ int num_envp, char *buffer, int buffer_size);
};