[PATCH] Re: NAK new drivers without proper power management?

Hi.

On Fri, 2007-02-09 at 19:50 -0600, Robert Han*** wrote:
It also kind of bothers me that if a driver has no suspend/resume
functions, and you suspend and resume the system, we don't complain
about it even though there's a very good chance that device is not going
to function properly. How about something in dmesg like:

Warning: driver for device XXXX has no suspend or resume support.
Device may not function properly after resume.

so that users know who to complain to. Maybe there are some devices that
truly don't need any handling for suspend, but if so I suspect the
number of those is small enough that adding empty functions would be a
good-enough solution.

Here's my current version of a patch to do this, if anyone wants to try
it out. It dumps stack with the warning to make it easier to see what
the source of the message is:

drivers/base/core.c | 25 +++++++++++++++++++++++++
drivers/pci/pci-driver.c | 6 ++++++
drivers/usb/core/driver.c | 5 +++++
include/linux/device.h | 1 +
4 files changed, 37 insertions(+)
diff -ruNp 920-report-no-pm-support.patch-old/drivers/base/core.c 920-report-no-pm-support.patch-new/drivers/base/core.c
--- 920-report-no-pm-support.patch-old/drivers/base/core.c 2007-02-06 14:48:31.000000000 +1100
+++ 920-report-no-pm-support.patch-new/drivers/base/core.c 2007-02-10 13:36:33.000000000 +1100
@@ -552,6 +552,30 @@ int device_add(struct device *dev)
class_intf->add_dev(dev, class_intf);
up(&dev->class->sem);
}
+
+#ifdef CONFIG_PM
+ {
+ int nosusp = 0, nores = 0;
+
+ if (!((dev->class && dev->class->suspend) ||
+ (dev->bus && (dev->bus->suspend || dev->bus->suspend_late))))
+ nosusp = 1;
+
+ if (!((dev->class && dev->class->resume) ||
+ (dev->bus && (dev->bus->resume || dev->bus->resume_early))))
+ nores = 1;
+
+ if ((nosusp || nores) && !dev->pm_safe) {
+ printk("Device driver %s lacks bus and class support for "
+ "being %s.\n",
+ kobject_name(&dev->kobj),
+ nosusp ? (nores ? "suspended or resumed" :
+ "resumed") : "suspended");
+ dump_stack();
+ }
+ }
+#endif
+
Done:
kfree(class_name);
put_device(dev);
@@ -851,6 +875,7 @@ struct device *device_create(struct clas
dev->class = class;
dev->parent = parent;
dev->release = device_create_release;
+ dev->pm_safe = 1;

va_start(args, fmt);
vsnprintf(dev->bus_id, BUS_ID_SIZE, fmt, args);
diff -ruNp 920-report-no-pm-support.patch-old/drivers/pci/pci-driver.c 920-report-no-pm-support.patch-new/drivers/pci/pci-driver.c
--- 920-report-no-pm-support.patch-old/drivers/pci/pci-driver.c 2007-02-06 14:48:44.000000000 +1100
+++ 920-report-no-pm-support.patch-new/drivers/pci/pci-driver.c 2007-02-10 14:00:39.000000000 +1100
@@ -449,6 +449,12 @@ int __pci_register_driver(struct pci_dri
if (error)
driver_unregister(&drv->driver);

+ if (!drv->suspend || !drv->resume)
+ printk("PCI driver %s lacks driver specific %s support.\n",
+ drv->name,
+ !drv->suspend ? (drv->resume ? "suspend" :
+ "suspend and resume") : "resume");
+
return error;
}

diff -ruNp 920-report-no-pm-support.patch-old/drivers/usb/core/driver.c 920-report-no-pm-support.patch-new/drivers/usb/core/driver.c
--- 920-report-no-pm-support.patch-old/drivers/usb/core/driver.c 2007-02-06 14:48:47.000000000 +1100
+++ 920-report-no-pm-support.patch-new/drivers/usb/core/driver.c 2007-02-10 12:32:57.000000000 +1100
@@ -709,6 +709,11 @@ int usb_register_device_driver(struct us
pr_info("%s: registered new device driver %s\n",
usbcore_name, new_udriver->name);
usbfs_update_special();
+ if (!new_udriver->suspend || !new_udriver->resume)
+ printk("USB driver %s lacks %s support.\n",
+ new_udriver->name, !new_udriver->suspend ?
+ (new_udriver->resume ? "suspend" :
+ "suspend and resume") : "resume");
} else {
printk(KERN_ERR "%s: error %d registering device "
" driver %s\n",
diff -ruNp 920-report-no-pm-support.patch-old/include/linux/device.h 920-report-no-pm-support.patch-new/include/linux/device.h
--- 920-report-no-pm-support.patch-old/include/linux/device.h 2007-02-06 14:48:56.000000000 +1100
+++ 920-report-no-pm-support.patch-new/include/linux/device.h 2007-02-10 13:36:01.000000000 +1100
@@ -356,6 +356,7 @@ struct device {
struct kobject kobj;
char bus_id[BUS_ID_SIZE]; /* position on parent bus */
unsigned is_registered:1;
+ unsigned pm_safe:1; /* No suspend/resume fns ok? */
struct device_attribute uevent_attr;
struct device_attribute *devt_attr;




My output:
nigel@nigel:~$ dmesg | grep lacks
[ 15.113674] Device driver platform lacks bus and class support for being suspended or resumed.
[ 15.131601] Device driver pci0000:00 lacks bus and class support for being suspended or resumed.
[ 15.179802] Device driver pnp0 lacks bus and class support for being suspended or resumed.
[ 15.972661] Device driver ide0 lacks bus and class support for being suspended or resumed.
[ 17.829746] Device driver ide1 lacks bus and class support for being suspended or resumed.
[ 17.830878] PCI driver ALI15x3_IDE lacks driver specific suspend and resume support.
[ 17.830963] PCI driver PIIX_IDE lacks driver specific suspend and resume support.
[ 17.878190] Device driver serio0 lacks bus and class support for being resumed.
[ 17.878442] Device driver serio1 lacks bus and class support for being resumed.
[ 17.878672] Device driver serio2 lacks bus and class support for being resumed.
[ 18.555856] Device driver serio3 lacks bus and class support for being resumed.
[ 18.558109] Device driver serio4 lacks bus and class support for being resumed.
[ 78.487717] Device driver usbdev1.1_ep00 lacks bus and class support for being suspended or resumed.
[ 78.595362] Device driver usbdev1.1_ep81 lacks bus and class support for being suspended or resumed.
[ 78.657382] Device driver usbdev2.1_ep00 lacks bus and class support for being suspended or resumed.
[ 78.765044] Device driver usbdev2.1_ep81 lacks bus and class support for being suspended or resumed.
[ 78.795324] Device driver usbdev3.1_ep00 lacks bus and class support for being suspended or resumed.
[ 78.904912] Device driver usbdev3.1_ep81 lacks bus and class support for being suspended or resumed.
[ 78.936997] PCI driver ali15x3_smbus lacks driver specific suspend and resume support.
[ 78.996318] PCI driver ali1535_smbus lacks driver specific suspend and resume support.


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