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Release 4.11 drivers/input/mouse/hgpk.c

Directory: drivers/input/mouse
/*
 * OLPC HGPK (XO-1) touchpad PS/2 mouse driver
 *
 * Copyright (c) 2006-2008 One Laptop Per Child
 * Authors:
 *   Zephaniah E. Hull
 *   Andres Salomon <dilinger@debian.org>
 *
 * This driver is partly based on the ALPS driver, which is:
 *
 * Copyright (c) 2003 Neil Brown <neilb@cse.unsw.edu.au>
 * Copyright (c) 2003-2005 Peter Osterlund <petero2@telia.com>
 * Copyright (c) 2004 Dmitry Torokhov <dtor@mail.ru>
 * Copyright (c) 2005 Vojtech Pavlik <vojtech@suse.cz>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

/*
 * The spec from ALPS is available from
 * <http://wiki.laptop.org/go/Touch_Pad/Tablet>.  It refers to this
 * device as HGPK (Hybrid GS, PT, and Keymatrix).
 *
 * The earliest versions of the device had simultaneous reporting; that
 * was removed.  After that, the device used the Advanced Mode GS/PT streaming
 * stuff.  That turned out to be too buggy to support, so we've finally
 * switched to Mouse Mode (which utilizes only the center 1/3 of the touchpad).
 */


#define DEBUG
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/module.h>
#include <linux/serio.h>
#include <linux/libps2.h>
#include <linux/delay.h>
#include <asm/olpc.h>

#include "psmouse.h"
#include "hgpk.h"


#define ILLEGAL_XY 999999


static bool tpdebug;
module_param(tpdebug, bool, 0644);
MODULE_PARM_DESC(tpdebug, "enable debugging, dumping packets to KERN_DEBUG.");


static int recalib_delta = 100;
module_param(recalib_delta, int, 0644);
MODULE_PARM_DESC(recalib_delta,
	"packets containing a delta this large will be discarded, and a "
	"recalibration may be scheduled.");


static int jumpy_delay = 20;
module_param(jumpy_delay, int, 0644);
MODULE_PARM_DESC(jumpy_delay,
	"delay (ms) before recal after jumpiness detected");


static int spew_delay = 1;
module_param(spew_delay, int, 0644);
MODULE_PARM_DESC(spew_delay,
	"delay (ms) before recal after packet spew detected");


static int recal_guard_time;
module_param(recal_guard_time, int, 0644);
MODULE_PARM_DESC(recal_guard_time,
	"interval (ms) during which recal will be restarted if packet received");


static int post_interrupt_delay = 40;
module_param(post_interrupt_delay, int, 0644);
MODULE_PARM_DESC(post_interrupt_delay,
	"delay (ms) before recal after recal interrupt detected");


static bool autorecal = true;
module_param(autorecal, bool, 0644);
MODULE_PARM_DESC(autorecal, "enable recalibration in the driver");


static char hgpk_mode_name[16];
module_param_string(hgpk_mode, hgpk_mode_name, sizeof(hgpk_mode_name), 0644);
MODULE_PARM_DESC(hgpk_mode,
	"default hgpk mode: mouse, glidesensor or pentablet");


static int hgpk_default_mode = HGPK_MODE_MOUSE;


static const char * const hgpk_mode_names[] = {
	[HGPK_MODE_MOUSE] = "Mouse",
	[HGPK_MODE_GLIDESENSOR] = "GlideSensor",
	[HGPK_MODE_PENTABLET] = "PenTablet",
};




static int hgpk_mode_from_name(const char *buf, int len)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(hgpk_mode_names); i++) {
		const char *name = hgpk_mode_names[i];
		if (strlen(name) == len && !strncasecmp(name, buf, len))
			return i;
	}

	return HGPK_MODE_INVALID;
}


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/*
 * see if new value is within 20% of half of old value
 */



static int approx_half(int curr, int prev)
{
	int belowhalf, abovehalf;

	if (curr < 5 || prev < 5)
		return 0;

	belowhalf = (prev * 8) / 20;
	abovehalf = (prev * 12) / 20;

	return belowhalf < curr && curr <= abovehalf;
}


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Andres Salomon11.69%150.00%


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/*
 * Throw out oddly large delta packets, and any that immediately follow whose
 * values are each approximately half of the previous.  It seems that the ALPS
 * firmware emits errant packets, and they get averaged out slowly.
 */



static int hgpk_discard_decay_hack(struct psmouse *psmouse, int x, int y)
{
	struct hgpk_data *priv = psmouse->private;
	int avx, avy;
	bool do_recal = false;

	avx = abs(x);
	avy = abs(y);

	/* discard if too big, or half that but > 4 times the prev delta */
	if (avx > recalib_delta ||
		(avx > recalib_delta / 2 && ((avx / 4) > priv->xlast))) {
		psmouse_warn(psmouse, "detected %dpx jump in x\n", x);
		priv->xbigj = avx;
	} else if (approx_half(avx, priv->xbigj)) {
		psmouse_warn(psmouse, "detected secondary %dpx jump in x\n", x);
		priv->xbigj = avx;
		priv->xsaw_secondary++;
	} else {
		if (priv->xbigj && priv->xsaw_secondary > 1)
			do_recal = true;
		priv->xbigj = 0;
		priv->xsaw_secondary = 0;
	}

	if (avy > recalib_delta ||
		(avy > recalib_delta / 2 && ((avy / 4) > priv->ylast))) {
		psmouse_warn(psmouse, "detected %dpx jump in y\n", y);
		priv->ybigj = avy;
	} else if (approx_half(avy, priv->ybigj)) {
		psmouse_warn(psmouse, "detected secondary %dpx jump in y\n", y);
		priv->ybigj = avy;
		priv->ysaw_secondary++;
	} else {
		if (priv->ybigj && priv->ysaw_secondary > 1)
			do_recal = true;
		priv->ybigj = 0;
		priv->ysaw_secondary = 0;
	}

	priv->xlast = avx;
	priv->ylast = avy;

	if (do_recal && jumpy_delay) {
		psmouse_warn(psmouse, "scheduling recalibration\n");
		psmouse_queue_work(psmouse, &priv->recalib_wq,
				msecs_to_jiffies(jumpy_delay));
	}

	return priv->xbigj || priv->ybigj;
}


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Paul Fox10.31%125.00%


Total318100.00%4100.00%






static void hgpk_reset_spew_detection(struct hgpk_data *priv)
{
	priv->spew_count = 0;
	priv->dupe_count = 0;
	priv->x_tally = 0;
	priv->y_tally = 0;
	priv->spew_flag = NO_SPEW;
}


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static void hgpk_reset_hack_state(struct psmouse *psmouse)
{
	struct hgpk_data *priv = psmouse->private;

	priv->abs_x = priv->abs_y = -1;
	priv->xlast = priv->ylast = ILLEGAL_XY;
	priv->xbigj = priv->ybigj = 0;
	priv->xsaw_secondary = priv->ysaw_secondary = 0;
	hgpk_reset_spew_detection(priv);
}


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/*
 * We have no idea why this particular hardware bug occurs.  The touchpad
 * will randomly start spewing packets without anything touching the
 * pad.  This wouldn't necessarily be bad, but it's indicative of a
 * severely miscalibrated pad; attempting to use the touchpad while it's
 * spewing means the cursor will jump all over the place, and act "drunk".
 *
 * The packets that are spewed tend to all have deltas between -2 and 2, and
 * the cursor will move around without really going very far.  It will
 * tend to end up in the same location; if we tally up the changes over
 * 100 packets, we end up w/ a final delta of close to 0.  This happens
 * pretty regularly when the touchpad is spewing, and is pretty hard to
 * manually trigger (at least for *my* fingers).  So, it makes a perfect
 * scheme for detecting spews.
 */



static void hgpk_spewing_hack(struct psmouse *psmouse,
			      int l, int r, int x, int y)
{
	struct hgpk_data *priv = psmouse->private;

	/* ignore button press packets; many in a row could trigger
         * a false-positive! */
	if (l || r)
		return;

	/* don't track spew if the workaround feature has been turned off */
	if (!spew_delay)
		return;

	if (abs(x) > 3 || abs(y) > 3) {
		/* no spew, or spew ended */
		hgpk_reset_spew_detection(priv);
		return;
	}

	/* Keep a tally of the overall delta to the cursor position caused by
         * the spew */
	priv->x_tally += x;
	priv->y_tally += y;

	switch (priv->spew_flag) {
	case NO_SPEW:
		/* we're not spewing, but this packet might be the start */
		priv->spew_flag = MAYBE_SPEWING;

		/* fall-through */

	case MAYBE_SPEWING:
		priv->spew_count++;

		if (priv->spew_count < SPEW_WATCH_COUNT)
			break;

		/* excessive spew detected, request recalibration */
		priv->spew_flag = SPEW_DETECTED;

		/* fall-through */

	case SPEW_DETECTED:
		/* only recalibrate when the overall delta to the cursor
                 * is really small. if the spew is causing significant cursor
                 * movement, it is probably a case of the user moving the
                 * cursor very slowly across the screen. */
		if (abs(priv->x_tally) < 3 && abs(priv->y_tally) < 3) {
			psmouse_warn(psmouse, "packet spew detected (%d,%d)\n",
				     priv->x_tally, priv->y_tally);
			priv->spew_flag = RECALIBRATING;
			psmouse_queue_work(psmouse, &priv->recalib_wq,
					   msecs_to_jiffies(spew_delay));
		}

		break;
	case RECALIBRATING:
		/* we already detected a spew and requested a recalibration,
                 * just wait for the queue to kick into action. */
		break;
	}
}


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Daniel Drake8744.16%125.00%


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Paul Fox10.51%125.00%


Total197100.00%4100.00%



/*
 * HGPK Mouse Mode format (standard mouse format, sans middle button)
 *
 * byte 0:      y-over  x-over  y-neg   x-neg   1       0       swr     swl
 * byte 1:      x7      x6      x5      x4      x3      x2      x1      x0
 * byte 2:      y7      y6      y5      y4      y3      y2      y1      y0
 *
 * swr/swl are the left/right buttons.
 * x-neg/y-neg are the x and y delta negative bits
 * x-over/y-over are the x and y overflow bits
 *
 * ---
 *
 * HGPK Advanced Mode - single-mode format
 *
 * byte 0(PT):  1    1    0    0    1    1     1     1
 * byte 0(GS):  1    1    1    1    1    1     1     1
 * byte 1:      0   x6   x5   x4   x3   x2    x1    x0
 * byte 2(PT):  0    0   x9   x8   x7    ? pt-dsw    0
 * byte 2(GS):  0  x10   x9   x8   x7    ? gs-dsw pt-dsw
 * byte 3:      0   y9   y8   y7    1    0   swr   swl
 * byte 4:      0   y6   y5   y4   y3   y2    y1    y0
 * byte 5:      0   z6   z5   z4   z3   z2    z1    z0
 *
 * ?'s are not defined in the protocol spec, may vary between models.
 *
 * swr/swl are the left/right buttons.
 *
 * pt-dsw/gs-dsw indicate that the pt/gs sensor is detecting a
 * pen/finger
 */



static bool hgpk_is_byte_valid(struct psmouse *psmouse, unsigned char *packet)
{
	struct hgpk_data *priv = psmouse->private;
	int pktcnt = psmouse->pktcnt;
	bool valid;

	switch (priv->mode) {
	case HGPK_MODE_MOUSE:
		valid = (packet[0] & 0x0C) == 0x08;
		break;

	case HGPK_MODE_GLIDESENSOR:
		valid = pktcnt == 1 ?
			packet[0] == HGPK_GS : !(packet[pktcnt - 1] & 0x80);
		break;

	case HGPK_MODE_PENTABLET:
		valid = pktcnt == 1 ?
			packet[0] == HGPK_PT : !(packet[pktcnt - 1] & 0x80);
		break;

	default:
		valid = false;
		break;
	}

	if (!valid)
		psmouse_dbg(psmouse,
			    "bad data, mode %d (%d) %*ph\n",
			    priv->mode, pktcnt, 6, psmouse->packet);

	return valid;
}


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Andres Salomon5737.75%125.00%


Andy Shevchenko21.32%125.00%


Dmitry Torokhov10.66%125.00%


Total151100.00%4100.00%






static void hgpk_process_advanced_packet(struct psmouse *psmouse)
{
	struct hgpk_data *priv = psmouse->private;
	struct input_dev *idev = psmouse->dev;
	unsigned char *packet = psmouse->packet;
	int down = !!(packet[2] & 2);
	int left = !!(packet[3] & 1);
	int right = !!(packet[3] & 2);
	int x = packet[1] | ((packet[2] & 0x78) << 4);
	int y = packet[4] | ((packet[3] & 0x70) << 3);

	if (priv->mode == HGPK_MODE_GLIDESENSOR) {
		int pt_down = !!(packet[2] & 1);
		int finger_down = !!(packet[2] & 2);
		int z = packet[5];

		input_report_abs(idev, ABS_PRESSURE, z);
		if (tpdebug)
			psmouse_dbg(psmouse, "pd=%d fd=%d z=%d",
				    pt_down, finger_down, z);
	} else {
		/*
                 * PenTablet mode does not report pressure, so we don't
                 * report it here
                 */
		if (tpdebug)
			psmouse_dbg(psmouse, "pd=%d ", down);
	}

	if (tpdebug)
		psmouse_dbg(psmouse, "l=%d r=%d x=%d y=%d\n",
			    left, right, x, y);

	input_report_key(idev, BTN_TOUCH, down);
	input_report_key(idev, BTN_LEFT, left);
	input_report_key(idev, BTN_RIGHT, right);

	/*
         * If this packet says that the finger was removed, reset our position
         * tracking so that we don't erroneously detect a jump on next press.
         */
	if (!down) {
		hgpk_reset_hack_state(psmouse);
		goto done;
	}

	/*
         * Weed out duplicate packets (we get quite a few, and they mess up
         * our jump detection)
         */
	if (x == priv->abs_x && y == priv->abs_y) {
		if (++priv->dupe_count > SPEW_WATCH_COUNT) {
			if (tpdebug)
				psmouse_dbg(psmouse, "hard spew detected\n");
			priv->spew_flag = RECALIBRATING;
			psmouse_queue_work(psmouse, &priv->recalib_wq,
					   msecs_to_jiffies(spew_delay));
		}
		goto done;
	}

	/* not a duplicate, continue with position reporting */
	priv->dupe_count = 0;

	/* Don't apply hacks in PT mode, it seems reliable */
	if (priv->mode != HGPK_MODE_PENTABLET && priv->abs_x != -1) {
		int x_diff = priv->abs_x - x;
		int y_diff = priv->abs_y - y;
		if (hgpk_discard_decay_hack(psmouse, x_diff, y_diff)) {
			if (tpdebug)
				psmouse_dbg(psmouse, "discarding\n");
			goto done;
		}
		hgpk_spewing_hack(psmouse, left, right, x_diff, y_diff);
	}

	input_report_abs(idev, ABS_X, x);
	input_report_abs(idev, ABS_Y, y);
	priv->abs_x = x;
	priv->abs_y = y;

done:
	input_sync(idev);
}


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static void hgpk_process_simple_packet(struct psmouse *psmouse)
{
	struct input_dev *dev = psmouse->dev;
	unsigned char *packet = psmouse->packet;
	int left = packet[0] & 1;
	int right = (packet[0] >> 1) & 1;
	int x = packet[1] - ((packet[0] << 4) & 0x100);
	int y = ((packet[0] << 3) & 0x100) - packet[2];

	if (packet[0] & 0xc0)
		psmouse_dbg(psmouse,
			    "overflow -- 0x%02x 0x%02x 0x%02x\n",
			    packet[0], packet[1], packet[2]);

	if (hgpk_discard_decay_hack(psmouse, x, y)) {
		if (tpdebug)
			psmouse_dbg(psmouse, "discarding\n");
		return;
	}

	hgpk_spewing_hack(psmouse, left, right, x, y);

	if (tpdebug)
		psmouse_dbg(psmouse, "l=%d r=%d x=%d y=%d\n",
			    left, right, x, y);

	input_report_key(dev, BTN_LEFT, left);
	input_report_key(dev, BTN_RIGHT, right);

	input_report_rel(dev, REL_X, x);
	input_report_rel(dev, REL_Y, y);

	input_sync(dev);
}


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static psmouse_ret_t hgpk_process_byte(struct psmouse *psmouse)
{
	struct hgpk_data *priv = psmouse->private;

	if (!hgpk_is_byte_valid(psmouse, psmouse->packet))
		return PSMOUSE_BAD_DATA;

	if (psmouse->pktcnt >= psmouse->pktsize) {
		if (priv->mode == HGPK_MODE_MOUSE)
			hgpk_process_simple_packet(psmouse);
		else
			hgpk_process_advanced_packet(psmouse);
		return PSMOUSE_FULL_PACKET;
	}

	if (priv->recalib_window) {
		if (time_before(jiffies, priv->recalib_window)) {
			/*
                         * ugh, got a packet inside our recalibration
                         * window, schedule another recalibration.
                         */
			psmouse_dbg(psmouse,
				    "packet inside calibration window, queueing another recalibration\n");
			psmouse_queue_work(psmouse, &priv->recalib_wq,
					msecs_to_jiffies(post_interrupt_delay));
		}
		priv->recalib_window = 0;
	}

	return PSMOUSE_GOOD_DATA;
}


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static int hgpk_select_mode(struct psmouse *psmouse)
{
	struct ps2dev *ps2dev = &psmouse->ps2dev;
	struct hgpk_data *priv = psmouse->private;
	int i;
	int cmd;

	/*
         * 4 disables to enable advanced mode
         * then 3 0xf2 bytes as the preamble for GS/PT selection
         */
	const int advanced_init[] = {
		PSMOUSE_CMD_DISABLE, PSMOUSE_CMD_DISABLE,
		PSMOUSE_CMD_DISABLE, PSMOUSE_CMD_DISABLE,
		0xf2, 0xf2, 0xf2,
        };

	switch (priv->mode) {
	case HGPK_MODE_MOUSE:
		psmouse->pktsize = 3;
		break;

	case HGPK_MODE_GLIDESENSOR:
	case HGPK_MODE_PENTABLET:
		psmouse->pktsize = 6;

		/* Switch to 'Advanced mode.', four disables in a row. */
		for (i = 0; i < ARRAY_SIZE(advanced_init); i++)
			if (ps2_command(ps2dev, NULL, advanced_init[i]))
				return -EIO;

		/* select between GlideSensor (mouse) or PenTablet */
		cmd = priv->mode == HGPK_MODE_GLIDESENSOR ?
			PSMOUSE_CMD_SETSCALE11 : PSMOUSE_CMD_SETSCALE21;

		if (ps2_command(ps2dev, NULL, cmd))
			return -EIO;
		break;

	default:
		return -EINVAL;
	}

	return 0;
}


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static void hgpk_setup_input_device(struct input_dev *input,
				    struct input_dev *old_input,
				    enum hgpk_mode mode)
{
	if (old_input) {
		input->name = old_input->name;
		input->phys = old_input->phys;
		input->id = old_input->id;
		input->dev.parent = old_input->dev.parent;
	}

	memset(input->evbit, 0, sizeof(input->evbit));
	memset(input->relbit, 0, sizeof(input->relbit));
	memset(input->keybit, 0, sizeof(input->keybit));

	/* All modes report left and right buttons */
	__set_bit(EV_KEY, input->evbit);
	__set_bit(BTN_LEFT, input->keybit);
	__set_bit(BTN_RIGHT, input->keybit);

	switch (mode) {
	case HGPK_MODE_MOUSE:
		__set_bit(EV_REL, input->evbit);
		__set_bit(REL_X, input->relbit);
		__set_bit(REL_Y, input->relbit);
		break;

	case HGPK_MODE_GLIDESENSOR:
		__set_bit(BTN_TOUCH, input->keybit);
		__set_bit(BTN_TOOL_FINGER, input->keybit);

		__set_bit(EV_ABS, input->evbit);

		/* GlideSensor has pressure sensor, PenTablet does not */
		input_set_abs_params(input, ABS_PRESSURE, 0, 15, 0, 0);

		/* From device specs */
		input_set_abs_params(input, ABS_X, 0, 399, 0, 0);
		input_set_abs_params(input, ABS_Y, 0, 290, 0, 0);

		/* Calculated by hand based on usable size (52mm x 38mm) */
		input_abs_set_res(input, ABS_X, 8);
		input_abs_set_res(input, ABS_Y, 8);
		break;

	case HGPK_MODE_PENTABLET:
		__set_bit(BTN_TOUCH, input->keybit);
		__set_bit(BTN_TOOL_FINGER, input->keybit);

		__set_bit(EV_ABS, input->evbit);

		/* From device specs */
		input_set_abs_params(input, ABS_X, 0, 999, 0, 0);
		input_set_abs_params(input, ABS_Y, 5, 239, 0, 0);

		/* Calculated by hand based on usable size (156mm x 38mm) */
		input_abs_set_res(input, ABS_X, 6);
		input_abs_set_res(input, ABS_Y, 8);
		break;

	default:
		BUG();
	}
}


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static int hgpk_reset_device(struct psmouse *psmouse, bool recalibrate)
{
	int err;

	psmouse_reset(psmouse);

	if (recalibrate) {
		struct ps2dev *ps2dev = &psmouse->ps2dev;

		/* send the recalibrate request */
		if (ps2_command(ps2dev, NULL, 0xf5) ||
		    ps2_command(ps2dev, NULL, 0xf5) ||
		    ps2_command(ps2dev, NULL, 0xe6) ||
		    ps2_command(ps2dev, NULL, 0xf5)) {
			return -1;
		}

		/* according to ALPS, 150mS is required for recalibration */
		msleep(150);
	}

	err = hgpk_select_mode(psmouse);
	if (err) {
		psmouse_err(psmouse, "failed to select mode\n");
		return err;
	}

	hgpk_reset_hack_state(psmouse);

	return 0;
}


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PersonTokensPropCommitsCommitProp
Daniel Drake8671.67%133.33%


Andres Salomon3327.50%133.33%


Dmitry Torokhov10.83%133.33%


Total120100.00%3100.00%






static int hgpk_force_recalibrate(struct psmouse *psmouse)
{
	struct hgpk_data *priv = psmouse->private;
	int err;

	/* C-series touchpads added the recalibrate command */
	if (psmouse->model < HGPK_MODEL_C)
		return 0;

	if (!autorecal) {
		psmouse_dbg(psmouse, "recalibration disabled, ignoring\n");
		return 0;
	}

	psmouse_dbg(psmouse, "recalibrating touchpad..\n");

	/* we don't want to race with the irq handler, nor with resyncs */
	psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);

	/* start by resetting the device */
	err = hgpk_reset_device(psmouse, true);
	if (err)
		return err;

	/*
         * XXX: If a finger is down during this delay, recalibration will
         * detect capacitance incorrectly.  This is a hardware bug, and
         * we don't have a good way to deal with it.  The 2s window stuff
         * (below) is our best option for now.
         */
	if (psmouse_activate(psmouse))
		return -1;

	if (tpdebug)
		psmouse_dbg(psmouse, "touchpad reactivated\n");

	/*
         * If we get packets right away after recalibrating, it's likely
         * that a finger was on the touchpad.  If so, it's probably
         * miscalibrated, so we optionally schedule another.
         */
	if (recal_guard_time)
		priv->recalib_window = jiffies +
			msecs_to_jiffies(recal_guard_time);

	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
Andres Salomon7257.14%116.67%


Daniel Drake4737.30%233.33%


Dmitry Torokhov43.17%116.67%


Paul Fox32.38%233.33%


Total126100.00%6100.00%



/*
 * This puts the touchpad in a power saving mode; according to ALPS, current
 * consumption goes down to 50uA after running this.  To turn power back on,
 * we drive MS-DAT low.  Measuring with a 1mA resolution ammeter says that
 * the current on the SUS_3.3V rail drops from 3mA or 4mA to 0 when we do this.
 *
 * We have no formal spec that details this operation -- the low-power
 * sequence came from a long-lost email trail.
 */



static int hgpk_toggle_powersave(struct psmouse *psmouse, int enable)
{
	struct ps2dev *ps2dev = &psmouse->ps2dev;
	int timeo;
	int err;

	/* Added on D-series touchpads */
	if (psmouse->model < HGPK_MODEL_D)
		return 0;

	if (enable) {
		psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);

		/*
                 * Sending a byte will drive MS-DAT low; this will wake up
                 * the controller.  Once we get an ACK back from it, it
                 * means we can continue with the touchpad re-init.  ALPS
                 * tells us that 1s should be long enough, so set that as
                 * the upper bound. (in practice, it takes about 3 loops.)
                 */
		for (timeo = 20; timeo > 0; timeo--) {
			if (!ps2_sendbyte(ps2dev, PSMOUSE_CMD_DISABLE, 20))
				break;
			msleep(25);
		}

		err = hgpk_reset_device(psmouse, false);
		if (err) {
			psmouse_err(psmouse, "Failed to reset device!\n");
			return err;
		}

		/* should be all set, enable the touchpad */
		psmouse_activate(psmouse);
		psmouse_dbg(psmouse, "Touchpad powered up.\n");
	} else {
		psmouse_dbg(psmouse, "Powering off touchpad.\n");

		if (ps2_command(ps2dev, NULL, 0xec) ||
		    ps2_command(ps2dev, NULL, 0xec) ||
		    ps2_command(ps2dev, NULL, 0xea)) {
			return -1;
		}

		psmouse_set_state(psmouse, PSMOUSE_IGNORE);

		/* probably won't see an ACK, the touchpad will be off */
		ps2_sendbyte(ps2dev, 0xec, 20);
	}

	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
Andres Salomon15078.12%120.00%


Daniel Drake2311.98%120.00%


Paul Fox168.33%240.00%


Dmitry Torokhov31.56%120.00%


Total192100.00%5100.00%






static int hgpk_poll(struct psmouse *psmouse)
{
	/* We can't poll, so always return failure. */
	return -1;
}


Contributors
PersonTokensPropCommitsCommitProp
Andres Salomon16100.00%1100.00%


Total16100.00%1100.00%






static int hgpk_reconnect(struct psmouse *psmouse)
{
	struct hgpk_data *priv = psmouse->private;

	/*
         * During suspend/resume the ps2 rails remain powered.  We don't want
         * to do a reset because it's flush data out of buffers; however,
         * earlier prototypes (B1) had some brokenness that required a reset.
         */
	if (olpc_board_at_least(olpc_board(0xb2)))
		if (psmouse->ps2dev.serio->dev.power.power_state.event !=
				PM_EVENT_ON)
			return 0;

	priv->powered = 1;
	return hgpk_reset_device(psmouse, false);
}


Contributors
PersonTokensPropCommitsCommitProp
Andres Salomon4669.70%133.33%


Paul Fox1522.73%133.33%


Daniel Drake57.58%133.33%


Total66100.00%3100.00%






static ssize_t hgpk_show_powered(struct psmouse *psmouse, void *data, char