On Wednesday 26 September 2007, Ishizaki Kou wrote:

This is a patch to support Power/Reset buttons on Beat on Celleb.

On Beat, we have an event from Beat if Power button or Reset button
is pressed. This patch catches the event and convert it to a signal
to INIT process.

/sbin/inittab have no entry to turn the machine power off so we have
to detect if power button is pressed or not internally in our driver.
This idea is taken from PS3's event handling subsystem.

Signed-off-by: Kou Ishizaki <redacted>

Basically looks good. At some point I want to do a similar driver
for the IBM cell blade, but I fear there is not much code we
can share.

+static irqreturn_t beat_power_event(int virq, void *arg)
+{
+	printk(KERN_DEBUG "Beat: power button pressed\n");
+	beat_pm_poweroff_flag = 1;
+	if (kill_cad_pid(SIGINT, 1)) {
+		/* Just in case killing init process failed */
+		beat_power_off();
+	}
+	return IRQ_HANDLED;
+}

I think this should call ctrl_alt_del() instead of doing 
kill_cad_pid() directly.

Also, I think you should better not call the low-level
beat_power_off() function, but rather a high-level function
that goes through the reboot notifiers first.

kernel_restart() seems appropriate for that.

+static irqreturn_t beat_reset_event(int virq, void *arg)
+{
+	printk(KERN_DEBUG "Beat: reset button pressed\n");
+	beat_pm_poweroff_flag = 0;
+	if (kill_cad_pid(SIGINT, 1)) {
+		/* Just in case killing init process failed */
+		beat_restart(NULL);
+	}
+	return IRQ_HANDLED;
+}

same here, except calling kernel_halt() in the end.

+static int __init beat_event_init(void)
+{
+	if (!machine_is(celleb) || !firmware_has_feature(FW_FEATURE_BEAT))
+		return -EINVAL;

Shouldn't one of the two be sufficent? It seems to me that you want to
probe for either celleb or BEAT, but not both, considering that celleb
implies BEAT.

	Arnd <><