On Čt 05-01-06 23:27:05, Dominik Brodowski wrote:

On Thu, Jan 05, 2006 at 11:23:38PM +0100, Pavel Machek wrote:

quoted

quoted

In addition, your patch breaks pcmcia / pcmciautils which already uses
numbers (which I already had to change from "3" to "2" before...).

pcmcia actually uses this? Ouch. Do you just read the power file, or
do you write to it, too?

Reading and writing. Replacement for "cardctl suspend" and "cardctl resume".


static int pccardctl_power_one(unsigned long socket_no, unsigned int device,
                               unsigned int power)
{
        int ret;
        char file[SYSFS_PATH_MAX];
        struct sysfs_attribute *attr;

        snprintf(file, SYSFS_PATH_MAX,
                 "/sys/bus/pcmcia/devices/%lu.%u/power/state",
                 socket_no, device);

        attr = sysfs_open_attribute(file);
        if (!attr)
                return -ENODEV;

        ret = sysfs_write_attribute(attr, power ? "2" : "0", 1);

        sysfs_close_attribute(attr);

        return (ret);
}


NB: it will break one day, one way or another, when gregkh makes the
/sys/class -> /sys/devices conversion. However, I'd want to try not to break
the new pcmciautils userspace too often...

Ok, so lets at least add value-checking to .../power file, and prevent
userspace see changes to PM_EVENT_SUSPEND value. 2 and 0 are now
"arbitrary cookies". I'd like to use "on" and "off", but pcmcia
apparently depends on "2" and "0", so...

Any objections?

Signed-off-by: Pavel Machek <redacted>
								Pavel

diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c

@@ -27,22 +27,25 @@
 
 static ssize_t state_show(struct device * dev, struct device_attribute *attr, char * buf)
 {
-	return sprintf(buf, "%u\n", dev->power.power_state.event);
+	if (dev->power.power_state.event)
+		return sprintf(buf, "2\n");
+	else
+		return sprintf(buf, "0\n");
 }
 
 static ssize_t state_store(struct device * dev, struct device_attribute *attr, const char * buf, size_t n)
 {
 	pm_message_t state;
-	char * rest;
-	int error = 0;
+	int error = -EINVAL;
 
-	state.event = simple_strtoul(buf, &rest, 10);
-	if (*rest)
-		return -EINVAL;
-	if (state.event)
-		error = dpm_runtime_suspend(dev, state);
-	else
+	state.event = PM_EVENT_SUSPEND;
+	if ((n == 1) && !strncmp(buf, "2", 1)) {
 		dpm_runtime_resume(dev);
+		error = 0;
+	}
+	if ((n == 1) && !strncmp(buf, "0", 1))
+		error = dpm_runtime_suspend(dev, state);
+
 	return error ? error : n;
 }
 

-- 
Thanks, Sharp!