1 files changed, 477 insertions, 0 deletions

diff --git a/drivers/input/mouse/hgpk.c b/drivers/input/mouse/hgpk.c
new file mode 100644
index 000000000000..e82d34201e97
--- /dev/null
+++ b/drivers/input/mouse/hgpk.c
@@ -0,0 +1,477 @@
+/*
+ * 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/input.h>
+#include <linux/serio.h>
+#include <linux/libps2.h>
+#include <linux/delay.h>
+#include <asm/olpc.h>
+
+#include "psmouse.h"
+#include "hgpk.h"
+
+static int tpdebug;
+module_param(tpdebug, int, 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 cause a recalibration.");
+
+/*
+ * When the touchpad gets ultra-sensitive, one can keep their finger 1/2"
+ * above the pad and still have it send packets.  This causes a jump cursor
+ * when one places their finger on the pad.  We can probably detect the
+ * jump as we see a large deltas (>= 100px).  In mouse mode, I've been
+ * unable to even come close to 100px deltas during normal usage, so I think
+ * this threshold is safe.  If a large delta occurs, trigger a recalibration.
+ */
+static void hgpk_jumpy_hack(struct psmouse *psmouse, int x, int y)
+{
+        struct hgpk_data *priv = psmouse->private;
+
+        if (abs(x) > recalib_delta || abs(y) > recalib_delta) {
+                hgpk_err(psmouse, ">%dpx jump detected (%d,%d)\n",
+                                recalib_delta, x, y);
+                /* My car gets forty rods to the hogshead and that's the
+                 * way I likes it! */
+                psmouse_queue_work(psmouse, &priv->recalib_wq,
+                                msecs_to_jiffies(1000));
+        }
+}
+
+/*
+ * 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;
+
+        priv->x_tally += x;
+        priv->y_tally += y;
+
+        if (++priv->count > 100) {
+                if (abs(priv->x_tally) < 3 && abs(priv->y_tally) < 3) {
+                        hgpk_dbg(psmouse, "packet spew detected (%d,%d)\n",
+                                 priv->x_tally, priv->y_tally);
+                        psmouse_queue_work(psmouse, &priv->recalib_wq,
+                                           msecs_to_jiffies(1000));
+                }
+                /* reset every 100 packets */
+                priv->count = 0;
+                priv->x_tally = 0;
+                priv->y_tally = 0;
+        }
+}
+
+/*
+ * 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
+ */
+static int hgpk_validate_byte(unsigned char *packet)
+{
+        return (packet[0] & 0x0C) == 0x08;
+}
+
+static void hgpk_process_packet(struct psmouse *psmouse)
+{
+        struct input_dev *dev = psmouse->dev;
+        unsigned char *packet = psmouse->packet;
+        int x, y, left, right;
+
+        left = packet[0] & 1;
+        right = (packet[0] >> 1) & 1;
+
+        x = packet[1] - ((packet[0] << 4) & 0x100);
+        y = ((packet[0] << 3) & 0x100) - packet[2];
+
+        hgpk_jumpy_hack(psmouse, x, y);
+        hgpk_spewing_hack(psmouse, left, right, x, y);
+
+        if (tpdebug)
+                hgpk_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_validate_byte(psmouse->packet)) {
+                hgpk_dbg(psmouse, "%s: (%d) %02x %02x %02x\n",
+                                __func__, psmouse->pktcnt, psmouse->packet[0],
+                                psmouse->packet[1], psmouse->packet[2]);
+                return PSMOUSE_BAD_DATA;
+        }
+
+        if (psmouse->pktcnt >= psmouse->pktsize) {
+                hgpk_process_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.
+                         */
+                        hgpk_dbg(psmouse,
+                                 "packet inside calibration window, "
+                                 "queueing another recalibration\n");
+                        psmouse_queue_work(psmouse, &priv->recalib_wq,
+                                        msecs_to_jiffies(1000));
+                }
+                priv->recalib_window = 0;
+        }
+
+        return PSMOUSE_GOOD_DATA;
+}
+
+static int hgpk_force_recalibrate(struct psmouse *psmouse)
+{
+        struct ps2dev *ps2dev = &psmouse->ps2dev;
+        struct hgpk_data *priv = psmouse->private;
+
+        /* C-series touchpads added the recalibrate command */
+        if (psmouse->model < HGPK_MODEL_C)
+                return 0;
+
+        /* we don't want to race with the irq handler, nor with resyncs */
+        psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
+
+        /* start by resetting the device */
+        psmouse_reset(psmouse);
+
+        /* 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);
+
+        /* 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 (ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE))
+                return -1;
+
+        psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
+
+        /* After we recalibrate, we shouldn't get any packets for 2s.  If
+         * we do, it's likely that someone's finger was on the touchpad.
+         * If someone's finger *was* on the touchpad, it's probably
+         * miscalibrated.  So, we should schedule another recalibration
+         */
+        priv->recalib_window = jiffies +  msecs_to_jiffies(2000);
+
+        return 0;
+}
+
+/*
+ * This kills power to the touchpad; according to ALPS, current consumption
+ * goes down to 50uA after running this.  To turn power back on, we drive
+ * MS-DAT low.
+ */
+static int hgpk_toggle_power(struct psmouse *psmouse, int enable)
+{
+        struct ps2dev *ps2dev = &psmouse->ps2dev;
+        int timeo;
+
+        /* 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.
+                 */
+                for (timeo = 20; timeo > 0; timeo--) {
+                        if (!ps2_sendbyte(&psmouse->ps2dev,
+                                        PSMOUSE_CMD_DISABLE, 20))
+                                break;
+                        msleep(50);
+                }
+
+                psmouse_reset(psmouse);
+
+                /* should be all set, enable the touchpad */
+                ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE);
+                psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
+
+        } else {
+                hgpk_dbg(psmouse, "Powering off touchpad.\n");
+                psmouse_set_state(psmouse, PSMOUSE_IGNORE);
+
+                if (ps2_command(ps2dev, NULL, 0xec) ||
+                    ps2_command(ps2dev, NULL, 0xec) ||
+                    ps2_command(ps2dev, NULL, 0xea)) {
+                        return -1;
+                }
+
+                /* probably won't see an ACK, the touchpad will be off */
+                ps2_sendbyte(&psmouse->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)
+{
+        /* 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;
+
+        psmouse_reset(psmouse);
+
+        return 0;
+}
+
+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 long value;
+        int err;
+
+        err = strict_strtoul(buf, 10, &value);
+        if (err || 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_power(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, 0);
+
+static void hgpk_disconnect(struct psmouse *psmouse)
+{
+        struct hgpk_data *priv = psmouse->private;
+
+        device_remove_file(&psmouse->ps2dev.serio->dev,
+                           &psmouse_attr_powered.dattr);
+        psmouse_reset(psmouse);
+        kfree(priv);
+}
+
+static void hgpk_recalib_work(struct work_struct *work)
+{
+        struct delayed_work *w = container_of(work, struct delayed_work, work);
+        struct hgpk_data *priv = container_of(w, struct hgpk_data, recalib_wq);
+        struct psmouse *psmouse = priv->psmouse;
+
+        hgpk_dbg(psmouse, "recalibrating touchpad..\n");
+
+        if (hgpk_force_recalibrate(psmouse))
+                hgpk_err(psmouse, "recalibration failed!\n");
+}
+
+static int hgpk_register(struct psmouse *psmouse)
+{
+        struct input_dev *dev = psmouse->dev;
+        int err;
+
+        /* unset the things that psmouse-base sets which we don't have */
+        __clear_bit(BTN_MIDDLE, dev->keybit);
+
+        /* set the things we do have */
+        __set_bit(EV_KEY, dev->evbit);
+        __set_bit(EV_REL, dev->evbit);
+
+        __set_bit(REL_X, dev->relbit);
+        __set_bit(REL_Y, dev->relbit);
+
+        __set_bit(BTN_LEFT, dev->keybit);
+        __set_bit(BTN_RIGHT, dev->keybit);
+
+        /* register handlers */
+        psmouse->protocol_handler = hgpk_process_byte;
+        psmouse->poll = hgpk_poll;
+        psmouse->disconnect = hgpk_disconnect;
+        psmouse->reconnect = hgpk_reconnect;
+        psmouse->pktsize = 3;
+
+        /* Disable the idle resync. */
+        psmouse->resync_time = 0;
+        /* Reset after a lot of bad bytes. */
+        psmouse->resetafter = 1024;
+
+        err = device_create_file(&psmouse->ps2dev.serio->dev,
+                                 &psmouse_attr_powered.dattr);
+        if (err)
+                hgpk_err(psmouse, "Failed to create sysfs attribute\n");
+
+        return err;
+}
+
+int hgpk_init(struct psmouse *psmouse)
+{
+        struct hgpk_data *priv;
+        int err = -ENOMEM;
+
+        priv = kzalloc(sizeof(struct hgpk_data), GFP_KERNEL);
+        if (!priv)
+                goto alloc_fail;
+
+        psmouse->private = priv;
+        priv->psmouse = psmouse;
+        priv->powered = 1;
+        INIT_DELAYED_WORK(&priv->recalib_wq, hgpk_recalib_work);
+
+        err = psmouse_reset(psmouse);
+        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;
+        }
+
+        hgpk_dbg(psmouse, "ID: %02x %02x %02x", param[0], param[1], param[2]);
+
+        /* HGPK signature: 0x67, 0x00, 0x<model> */
+        if (param[0] != 0x67 || param[1] != 0x00)
+                return -ENODEV;
+
+        hgpk_info(psmouse, "OLPC touchpad revision 0x%x\n", param[2]);
+
+        return param[2];
+}
+
+int hgpk_detect(struct psmouse *psmouse, int 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;
+}