[PATCH] appletouch powersaving - please apply for 2.6.23-rc1

[Soeren Sonnenburg <kernel@nn7.de>]

[-- Attachment #1: Type: text/plain, Size: 6867 bytes --]

Hi,

the attached minimally intrusive patch is based on Matthew Garret's
patch 'Make appletouch shut up when it has nothing to say' patches (e.g.
http://lkml.org/lkml/2007/5/13/117): Matthews description follows /
second paragraph lists my additional changes.

The appletouch geyser3 devices found in the Intel Macs (and possibly some later 
PPC ones?) send a constant stream of packets after the first touch. This 
results in the kernel waking up around once every couple of milliseconds 
to process them, making it almost impossible to spend any significant 
period of time in C3 state on a dynamic HZ kernel. Sending the mode 
initialization code makes the device shut up until it's touched again. 
This patch does so after receiving 10 packets with no interesting 
content.

In addition it now empties the work queue via cancel_work_sync on module
exit, keeps all error checking and only reports BTN_LEFT presses if bit
1 in the status byte (last byte in packet) is set. This fixes the random
left clicks issue. Furthermore it invalidates touchpad data before the
mode switch, which fixes the touchpad runs amok issue.

Credits:
Sven Anders found out that one should only check for bit 1 for BTN_LEFT.
Matthew Garrett did the initial 'Make appletouch shut up when it has
nothing to say' so I am adding him to the signed-off lines (hope that is
the correct way).

Patch follows inline and attached.

Soeren.

Signed-off-by: Soeren Sonnenburg <kernel@nn7.de>
Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>

diff --git a/drivers/input/mouse/appletouch.c b/drivers/input/mouse/appletouch.c
index e321526..0426054 100644
--- a/drivers/input/mouse/appletouch.c
+++ b/drivers/input/mouse/appletouch.c
@@ -155,6 +155,8 @@ struct atp {
 	int			xy_acc[ATP_XSENSORS + ATP_YSENSORS];
 	int			overflowwarn;	/* overflow warning printed? */
 	int			datalen;	/* size of an USB urb transfer */
+	int                     idlecount;      /* number of empty packets */
+	struct work_struct      work;
 };
 
 #define dbg_dump(msg, tab) \
@@ -208,6 +210,64 @@ static inline int atp_is_geyser_3(struct atp *dev)
 		(productId == GEYSER4_JIS_PRODUCT_ID);
 }
 
+/*
+ * By default Geyser 3 device sends standard USB HID mouse
+ * packets (Report ID 2). This code changes device mode, so it
+ * sends raw sensor reports (Report ID 5).
+ */
+static int atp_geyser3_init(struct usb_device *udev)
+{
+	char data[8];
+	int size;
+	int i;
+
+	size = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
+			       ATP_GEYSER3_MODE_READ_REQUEST_ID,
+			       USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+			       ATP_GEYSER3_MODE_REQUEST_VALUE,
+			       ATP_GEYSER3_MODE_REQUEST_INDEX, &data, 8, 5000);
+
+
+	if (size != 8) {
+		printk("appletouch atp_geyser3_init READ error\n");
+		for (i=0; i<8; i++)
+			printk("appletouch[%d]: %d\n", i, (int) data[i]);
+
+		err("Could not do mode read request from device"
+		    " (Geyser 3 mode)");
+		return -EIO;
+	}
+
+	/* Apply the mode switch */
+	data[0] = ATP_GEYSER3_MODE_VENDOR_VALUE;
+
+	size = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+			       ATP_GEYSER3_MODE_WRITE_REQUEST_ID,
+			       USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+			       ATP_GEYSER3_MODE_REQUEST_VALUE,
+			       ATP_GEYSER3_MODE_REQUEST_INDEX, &data, 8, 5000);
+	
+	if (size != 8) {
+		printk("appletouch atp_geyser3_init WRITE error\n");
+		for (i=0; i<8; i++)
+			printk("appletouch[%d]: %d\n", i, (int) data[i]);
+		err("Could not do mode write request to device"
+		    " (Geyser 3 mode)");
+		return -EIO;
+	}
+	return 0;
+}
+
+/* Reinitialise the device if it's a geyser 3 */
+static void atp_reinit(struct work_struct *work)
+{
+	struct atp *dev = container_of(work, struct atp, work);
+	struct usb_device *udev = dev->udev;
+
+	dev->idlecount = 0;
+	atp_geyser3_init(udev);
+}
+
 static int atp_calculate_abs(int *xy_sensors, int nb_sensors, int fact,
 			     int *z, int *fingers)
 {
@@ -418,6 +478,8 @@ static void atp_complete(struct urb* urb)
 	y = atp_calculate_abs(dev->xy_acc + ATP_XSENSORS, ATP_YSENSORS,
 			      ATP_YFACT, &y_z, &y_f);
 
+	input_report_key(dev->input, BTN_LEFT, dev->data[dev->datalen-1] & 1);
+
 	if (x && y) {
 		if (dev->x_old != -1) {
 			x = (dev->x_old * 3 + x) >> 2;
@@ -449,10 +511,19 @@ static void atp_complete(struct urb* urb)
 
 		/* reset the accumulator on release */
 		memset(dev->xy_acc, 0, sizeof(dev->xy_acc));
-	}
 
-	input_report_key(dev->input, BTN_LEFT,
-			 !!dev->data[dev->datalen - 1]);
+		/* Geyser 3 will continue to send packets continually after
+		   the first touch unless reinitialised. Do so if it's been
+		   idle for a while in order to avoid waking the kernel up
+		   several hundred times a second */
+		if (atp_is_geyser_3(dev)) {
+			dev->idlecount++;
+			if (dev->idlecount == 10) {
+				dev->valid=0;
+				schedule_work (&dev->work);
+			}
+		}
+	}
 
 	input_sync(dev->input);
 
@@ -528,40 +599,10 @@ static int atp_probe(struct usb_interface *iface, const struct usb_device_id *id
 		dev->datalen = 81;
 
 	if (atp_is_geyser_3(dev)) {
-		/*
-		 * By default Geyser 3 device sends standard USB HID mouse
-		 * packets (Report ID 2). This code changes device mode, so it
-		 * sends raw sensor reports (Report ID 5).
-		 */
-		char data[8];
-		int size;
-
-		size = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
-			ATP_GEYSER3_MODE_READ_REQUEST_ID,
-			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
-			ATP_GEYSER3_MODE_REQUEST_VALUE,
-			ATP_GEYSER3_MODE_REQUEST_INDEX, &data, 8, 5000);
-
-		if (size != 8) {
-			err("Could not do mode read request from device"
-							" (Geyser 3 mode)");
+		/* switch to raw sensor mode */
+		if (atp_geyser3_init(udev))
 			goto err_free_devs;
-		}
-
-		/* Apply the mode switch */
-		data[0] = ATP_GEYSER3_MODE_VENDOR_VALUE;
 
-		size = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
-			ATP_GEYSER3_MODE_WRITE_REQUEST_ID,
-			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
-			ATP_GEYSER3_MODE_REQUEST_VALUE,
-			ATP_GEYSER3_MODE_REQUEST_INDEX, &data, 8, 5000);
-
-		if (size != 8) {
-			err("Could not do mode write request to device"
-							" (Geyser 3 mode)");
-			goto err_free_devs;
-		}
 		printk("appletouch Geyser 3 inited.\n");
 	}
 
@@ -636,6 +677,8 @@ static int atp_probe(struct usb_interface *iface, const struct usb_device_id *id
 	/* save our data pointer in this interface device */
 	usb_set_intfdata(iface, dev);
 
+	INIT_WORK(&dev->work, atp_reinit);
+
 	return 0;
 
  err_free_buffer:
@@ -656,6 +699,7 @@ static void atp_disconnect(struct usb_interface *iface)
 
 	usb_set_intfdata(iface, NULL);
 	if (dev) {
+		cancel_work_sync(&dev->work);
 		usb_kill_urb(dev->urb);
 		input_unregister_device(dev->input);
 		usb_buffer_free(dev->udev, dev->datalen,

-- 
Sometimes, there's a moment as you're waking, when you become aware of
the real world around you, but you're still dreaming.

[-- Attachment #2: appletouch.patch --]
[-- Type: text/x-patch, Size: 5392 bytes --]

diff --git a/drivers/input/mouse/appletouch.c b/drivers/input/mouse/appletouch.c
index e321526..0426054 100644
--- a/drivers/input/mouse/appletouch.c
+++ b/drivers/input/mouse/appletouch.c
@@ -155,6 +155,8 @@ struct atp {
 	int			xy_acc[ATP_XSENSORS + ATP_YSENSORS];
 	int			overflowwarn;	/* overflow warning printed? */
 	int			datalen;	/* size of an USB urb transfer */
+	int                     idlecount;      /* number of empty packets */
+	struct work_struct      work;
 };
 
 #define dbg_dump(msg, tab) \
@@ -208,6 +210,64 @@ static inline int atp_is_geyser_3(struct atp *dev)
 		(productId == GEYSER4_JIS_PRODUCT_ID);
 }
 
+/*
+ * By default Geyser 3 device sends standard USB HID mouse
+ * packets (Report ID 2). This code changes device mode, so it
+ * sends raw sensor reports (Report ID 5).
+ */
+static int atp_geyser3_init(struct usb_device *udev)
+{
+	char data[8];
+	int size;
+	int i;
+
+	size = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
+			       ATP_GEYSER3_MODE_READ_REQUEST_ID,
+			       USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+			       ATP_GEYSER3_MODE_REQUEST_VALUE,
+			       ATP_GEYSER3_MODE_REQUEST_INDEX, &data, 8, 5000);
+
+
+	if (size != 8) {
+		printk("appletouch atp_geyser3_init READ error\n");
+		for (i=0; i<8; i++)
+			printk("appletouch[%d]: %d\n", i, (int) data[i]);
+
+		err("Could not do mode read request from device"
+		    " (Geyser 3 mode)");
+		return -EIO;
+	}
+
+	/* Apply the mode switch */
+	data[0] = ATP_GEYSER3_MODE_VENDOR_VALUE;
+
+	size = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+			       ATP_GEYSER3_MODE_WRITE_REQUEST_ID,
+			       USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+			       ATP_GEYSER3_MODE_REQUEST_VALUE,
+			       ATP_GEYSER3_MODE_REQUEST_INDEX, &data, 8, 5000);
+	
+	if (size != 8) {
+		printk("appletouch atp_geyser3_init WRITE error\n");
+		for (i=0; i<8; i++)
+			printk("appletouch[%d]: %d\n", i, (int) data[i]);
+		err("Could not do mode write request to device"
+		    " (Geyser 3 mode)");
+		return -EIO;
+	}
+	return 0;
+}
+
+/* Reinitialise the device if it's a geyser 3 */
+static void atp_reinit(struct work_struct *work)
+{
+	struct atp *dev = container_of(work, struct atp, work);
+	struct usb_device *udev = dev->udev;
+
+	dev->idlecount = 0;
+	atp_geyser3_init(udev);
+}
+
 static int atp_calculate_abs(int *xy_sensors, int nb_sensors, int fact,
 			     int *z, int *fingers)
 {
@@ -418,6 +478,8 @@ static void atp_complete(struct urb* urb)
 	y = atp_calculate_abs(dev->xy_acc + ATP_XSENSORS, ATP_YSENSORS,
 			      ATP_YFACT, &y_z, &y_f);
 
+	input_report_key(dev->input, BTN_LEFT, dev->data[dev->datalen-1] & 1);
+
 	if (x && y) {
 		if (dev->x_old != -1) {
 			x = (dev->x_old * 3 + x) >> 2;
@@ -449,10 +511,19 @@ static void atp_complete(struct urb* urb)
 
 		/* reset the accumulator on release */
 		memset(dev->xy_acc, 0, sizeof(dev->xy_acc));
-	}
 
-	input_report_key(dev->input, BTN_LEFT,
-			 !!dev->data[dev->datalen - 1]);
+		/* Geyser 3 will continue to send packets continually after
+		   the first touch unless reinitialised. Do so if it's been
+		   idle for a while in order to avoid waking the kernel up
+		   several hundred times a second */
+		if (atp_is_geyser_3(dev)) {
+			dev->idlecount++;
+			if (dev->idlecount == 10) {
+				dev->valid=0;
+				schedule_work (&dev->work);
+			}
+		}
+	}
 
 	input_sync(dev->input);
 
@@ -528,40 +599,10 @@ static int atp_probe(struct usb_interface *iface, const struct usb_device_id *id
 		dev->datalen = 81;
 
 	if (atp_is_geyser_3(dev)) {
-		/*
-		 * By default Geyser 3 device sends standard USB HID mouse
-		 * packets (Report ID 2). This code changes device mode, so it
-		 * sends raw sensor reports (Report ID 5).
-		 */
-		char data[8];
-		int size;
-
-		size = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
-			ATP_GEYSER3_MODE_READ_REQUEST_ID,
-			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
-			ATP_GEYSER3_MODE_REQUEST_VALUE,
-			ATP_GEYSER3_MODE_REQUEST_INDEX, &data, 8, 5000);
-
-		if (size != 8) {
-			err("Could not do mode read request from device"
-							" (Geyser 3 mode)");
+		/* switch to raw sensor mode */
+		if (atp_geyser3_init(udev))
 			goto err_free_devs;
-		}
-
-		/* Apply the mode switch */
-		data[0] = ATP_GEYSER3_MODE_VENDOR_VALUE;
 
-		size = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
-			ATP_GEYSER3_MODE_WRITE_REQUEST_ID,
-			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
-			ATP_GEYSER3_MODE_REQUEST_VALUE,
-			ATP_GEYSER3_MODE_REQUEST_INDEX, &data, 8, 5000);
-
-		if (size != 8) {
-			err("Could not do mode write request to device"
-							" (Geyser 3 mode)");
-			goto err_free_devs;
-		}
 		printk("appletouch Geyser 3 inited.\n");
 	}
 
@@ -636,6 +677,8 @@ static int atp_probe(struct usb_interface *iface, const struct usb_device_id *id
 	/* save our data pointer in this interface device */
 	usb_set_intfdata(iface, dev);
 
+	INIT_WORK(&dev->work, atp_reinit);
+
 	return 0;
 
  err_free_buffer:
@@ -656,6 +699,7 @@ static void atp_disconnect(struct usb_interface *iface)
 
 	usb_set_intfdata(iface, NULL);
 	if (dev) {
+		cancel_work_sync(&dev->work);
 		usb_kill_urb(dev->urb);
 		input_unregister_device(dev->input);
 		usb_buffer_free(dev->udev, dev->datalen,