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-rw-r--r--drivers/input/mouse/hgpk.c1063
1 files changed, 1063 insertions, 0 deletions
diff --git a/drivers/input/mouse/hgpk.c b/drivers/input/mouse/hgpk.c
new file mode 100644
index 000000000..4dc441309
--- /dev/null
+++ b/drivers/input/mouse/hgpk.c
@@ -0,0 +1,1063 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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>
+ */
+
+/*
+ * 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;
+}
+
+/*
+ * 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;
+}
+
+/*
+ * 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;
+}
+
+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;
+}
+
+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);
+}
+
+/*
+ * 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;
+
+ fallthrough;
+
+ case MAYBE_SPEWING:
+ priv->spew_count++;
+
+ if (priv->spew_count < SPEW_WATCH_COUNT)
+ break;
+
+ /* excessive spew detected, request recalibration */
+ priv->spew_flag = SPEW_DETECTED;
+
+ fallthrough;
+
+ 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;
+ }
+}
+
+/*
+ * 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;
+}
+
+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);
+}
+
+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);
+}
+
+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;
+}
+
+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;
+}
+
+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();
+ }
+}
+
+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;
+}
+
+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;
+}
+
+/*
+ * 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;
+}
+
+static int hgpk_poll(struct psmouse *psmouse)
+{
+ /* We can't poll, so always return failure. */
+ return -1;
+}
+
+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);
+}
+
+static ssize_t hgpk_show_powered(struct psmouse *psmouse, void *data, char *buf)
+{
+ struct hgpk_data *priv = psmouse->private;
+
+ return sprintf(buf, "%d\n", priv->powered);
+}
+
+static ssize_t hgpk_set_powered(struct psmouse *psmouse, void *data,
+ const char *buf, size_t count)
+{
+ struct hgpk_data *priv = psmouse->private;
+ unsigned int value;
+ int err;
+
+ err = kstrtouint(buf, 10, &value);
+ if (err)
+ return err;
+
+ if (value > 1)
+ return -EINVAL;
+
+ if (value != priv->powered) {
+ /*
+ * hgpk_toggle_power will deal w/ state so
+ * we're not racing w/ irq
+ */
+ err = hgpk_toggle_powersave(psmouse, value);
+ if (!err)
+ priv->powered = value;
+ }
+
+ return err ? err : count;
+}
+
+__PSMOUSE_DEFINE_ATTR(powered, S_IWUSR | S_IRUGO, NULL,
+ hgpk_show_powered, hgpk_set_powered, false);
+
+static ssize_t attr_show_mode(struct psmouse *psmouse, void *data, char *buf)
+{
+ struct hgpk_data *priv = psmouse->private;
+
+ return sprintf(buf, "%s\n", hgpk_mode_names[priv->mode]);
+}
+
+static ssize_t attr_set_mode(struct psmouse *psmouse, void *data,
+ const char *buf, size_t len)
+{
+ struct hgpk_data *priv = psmouse->private;
+ enum hgpk_mode old_mode = priv->mode;
+ enum hgpk_mode new_mode = hgpk_mode_from_name(buf, len);
+ struct input_dev *old_dev = psmouse->dev;
+ struct input_dev *new_dev;
+ int err;
+
+ if (new_mode == HGPK_MODE_INVALID)
+ return -EINVAL;
+
+ if (old_mode == new_mode)
+ return len;
+
+ new_dev = input_allocate_device();
+ if (!new_dev)
+ return -ENOMEM;
+
+ psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
+
+ /* Switch device into the new mode */
+ priv->mode = new_mode;
+ err = hgpk_reset_device(psmouse, false);
+ if (err)
+ goto err_try_restore;
+
+ hgpk_setup_input_device(new_dev, old_dev, new_mode);
+
+ psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
+
+ err = input_register_device(new_dev);
+ if (err)
+ goto err_try_restore;
+
+ psmouse->dev = new_dev;
+ input_unregister_device(old_dev);
+
+ return len;
+
+err_try_restore:
+ input_free_device(new_dev);
+ priv->mode = old_mode;
+ hgpk_reset_device(psmouse, false);
+
+ return err;
+}
+
+PSMOUSE_DEFINE_ATTR(hgpk_mode, S_IWUSR | S_IRUGO, NULL,
+ attr_show_mode, attr_set_mode);
+
+static ssize_t hgpk_trigger_recal_show(struct psmouse *psmouse,
+ void *data, char *buf)
+{
+ return -EINVAL;
+}
+
+static ssize_t hgpk_trigger_recal(struct psmouse *psmouse, void *data,
+ const char *buf, size_t count)
+{
+ struct hgpk_data *priv = psmouse->private;
+ unsigned int value;
+ int err;
+
+ err = kstrtouint(buf, 10, &value);
+ if (err)
+ return err;
+
+ if (value != 1)
+ return -EINVAL;
+
+ /*
+ * We queue work instead of doing recalibration right here
+ * to avoid adding locking to to hgpk_force_recalibrate()
+ * since workqueue provides serialization.
+ */
+ psmouse_queue_work(psmouse, &priv->recalib_wq, 0);
+ return count;
+}
+
+__PSMOUSE_DEFINE_ATTR(recalibrate, S_IWUSR | S_IRUGO, NULL,
+ hgpk_trigger_recal_show, hgpk_trigger_recal, false);
+
+static void hgpk_disconnect(struct psmouse *psmouse)
+{
+ struct hgpk_data *priv = psmouse->private;
+
+ device_remove_file(&psmouse->ps2dev.serio->dev,
+ &psmouse_attr_powered.dattr);
+ device_remove_file(&psmouse->ps2dev.serio->dev,
+ &psmouse_attr_hgpk_mode.dattr);
+
+ if (psmouse->model >= HGPK_MODEL_C)
+ device_remove_file(&psmouse->ps2dev.serio->dev,
+ &psmouse_attr_recalibrate.dattr);
+
+ psmouse_reset(psmouse);
+ kfree(priv);
+}
+
+static void hgpk_recalib_work(struct work_struct *work)
+{
+ struct delayed_work *w = to_delayed_work(work);
+ struct hgpk_data *priv = container_of(w, struct hgpk_data, recalib_wq);
+ struct psmouse *psmouse = priv->psmouse;
+
+ if (hgpk_force_recalibrate(psmouse))
+ psmouse_err(psmouse, "recalibration failed!\n");
+}
+
+static int hgpk_register(struct psmouse *psmouse)
+{
+ struct hgpk_data *priv = psmouse->private;
+ int err;
+
+ /* register handlers */
+ psmouse->protocol_handler = hgpk_process_byte;
+ psmouse->poll = hgpk_poll;
+ psmouse->disconnect = hgpk_disconnect;
+ psmouse->reconnect = hgpk_reconnect;
+
+ /* Disable the idle resync. */
+ psmouse->resync_time = 0;
+ /* Reset after a lot of bad bytes. */
+ psmouse->resetafter = 1024;
+
+ hgpk_setup_input_device(psmouse->dev, NULL, priv->mode);
+
+ err = device_create_file(&psmouse->ps2dev.serio->dev,
+ &psmouse_attr_powered.dattr);
+ if (err) {
+ psmouse_err(psmouse, "Failed creating 'powered' sysfs node\n");
+ return err;
+ }
+
+ err = device_create_file(&psmouse->ps2dev.serio->dev,
+ &psmouse_attr_hgpk_mode.dattr);
+ if (err) {
+ psmouse_err(psmouse,
+ "Failed creating 'hgpk_mode' sysfs node\n");
+ goto err_remove_powered;
+ }
+
+ /* C-series touchpads added the recalibrate command */
+ if (psmouse->model >= HGPK_MODEL_C) {
+ err = device_create_file(&psmouse->ps2dev.serio->dev,
+ &psmouse_attr_recalibrate.dattr);
+ if (err) {
+ psmouse_err(psmouse,
+ "Failed creating 'recalibrate' sysfs node\n");
+ goto err_remove_mode;
+ }
+ }
+
+ return 0;
+
+err_remove_mode:
+ device_remove_file(&psmouse->ps2dev.serio->dev,
+ &psmouse_attr_hgpk_mode.dattr);
+err_remove_powered:
+ device_remove_file(&psmouse->ps2dev.serio->dev,
+ &psmouse_attr_powered.dattr);
+ return err;
+}
+
+int hgpk_init(struct psmouse *psmouse)
+{
+ struct hgpk_data *priv;
+ int err;
+
+ priv = kzalloc(sizeof(struct hgpk_data), GFP_KERNEL);
+ if (!priv) {
+ err = -ENOMEM;
+ goto alloc_fail;
+ }
+
+ psmouse->private = priv;
+
+ priv->psmouse = psmouse;
+ priv->powered = true;
+ priv->mode = hgpk_default_mode;
+ INIT_DELAYED_WORK(&priv->recalib_wq, hgpk_recalib_work);
+
+ err = hgpk_reset_device(psmouse, false);
+ if (err)
+ goto init_fail;
+
+ err = hgpk_register(psmouse);
+ if (err)
+ goto init_fail;
+
+ return 0;
+
+init_fail:
+ kfree(priv);
+alloc_fail:
+ return err;
+}
+
+static enum hgpk_model_t hgpk_get_model(struct psmouse *psmouse)
+{
+ struct ps2dev *ps2dev = &psmouse->ps2dev;
+ unsigned char param[3];
+
+ /* E7, E7, E7, E9 gets us a 3 byte identifier */
+ if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) ||
+ ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) ||
+ ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) ||
+ ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
+ return -EIO;
+ }
+
+ psmouse_dbg(psmouse, "ID: %*ph\n", 3, param);
+
+ /* HGPK signature: 0x67, 0x00, 0x<model> */
+ if (param[0] != 0x67 || param[1] != 0x00)
+ return -ENODEV;
+
+ psmouse_info(psmouse, "OLPC touchpad revision 0x%x\n", param[2]);
+
+ return param[2];
+}
+
+int hgpk_detect(struct psmouse *psmouse, bool set_properties)
+{
+ int version;
+
+ version = hgpk_get_model(psmouse);
+ if (version < 0)
+ return version;
+
+ if (set_properties) {
+ psmouse->vendor = "ALPS";
+ psmouse->name = "HGPK";
+ psmouse->model = version;
+ }
+
+ return 0;
+}
+
+void hgpk_module_init(void)
+{
+ hgpk_default_mode = hgpk_mode_from_name(hgpk_mode_name,
+ strlen(hgpk_mode_name));
+ if (hgpk_default_mode == HGPK_MODE_INVALID) {
+ hgpk_default_mode = HGPK_MODE_MOUSE;
+ strlcpy(hgpk_mode_name, hgpk_mode_names[HGPK_MODE_MOUSE],
+ sizeof(hgpk_mode_name));
+ }
+}