1 files changed, 137 insertions, 127 deletions

diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c
index 880f58c6a7c4..7ef0d1420d3c 100644
--- a/drivers/input/touchscreen/tsc2007.c
+++ b/drivers/input/touchscreen/tsc2007.c
@@ -21,15 +21,14 @@
  */
 
 #include <linux/module.h>
-#include <linux/hrtimer.h>
 #include <linux/slab.h>
 #include <linux/input.h>
 #include <linux/interrupt.h>
 #include <linux/i2c.h>
 #include <linux/i2c/tsc2007.h>
 
-#define TS_POLL_DELAY   (10 * 1000)     /* ns delay before the first sample */
-#define TS_POLL_PERIOD  (5 * 1000)      /* ns delay between samples */
+#define TS_POLL_DELAY                   1 /* ms delay between samples */
+#define TS_POLL_PERIOD                  1 /* ms delay between samples */
 
 #define TSC2007_MEASURE_TEMP0           (0x0 << 4)
 #define TSC2007_MEASURE_AUX             (0x2 << 4)
@@ -70,17 +69,14 @@ struct ts_event {
 struct tsc2007 {
         struct input_dev        *input;
         char                    phys[32];
-        struct hrtimer          timer;
-        struct ts_event         tc;
+        struct delayed_work     work;
 
         struct i2c_client       *client;
 
-        spinlock_t              lock;
-
         u16                     model;
         u16                     x_plate_ohms;
 
-        unsigned                pendown;
+        bool                    pendown;
         int                     irq;
 
         int                     (*get_pendown_state)(void);
@@ -109,52 +105,96 @@ static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
         return val;
 }
 
-static void tsc2007_send_event(void *tsc)
+static void tsc2007_read_values(struct tsc2007 *tsc, struct ts_event *tc)
 {
-        struct tsc2007  *ts = tsc;
-        u32             rt;
-        u16             x, y, z1, z2;
+        /* y- still on; turn on only y+ (and ADC) */
+        tc->y = tsc2007_xfer(tsc, READ_Y);
+
+        /* turn y- off, x+ on, then leave in lowpower */
+        tc->x = tsc2007_xfer(tsc, READ_X);
+
+        /* turn y+ off, x- on; we'll use formula #1 */
+        tc->z1 = tsc2007_xfer(tsc, READ_Z1);
+        tc->z2 = tsc2007_xfer(tsc, READ_Z2);
 
-        x = ts->tc.x;
-        y = ts->tc.y;
-        z1 = ts->tc.z1;
-        z2 = ts->tc.z2;
+        /* Prepare for next touch reading - power down ADC, enable PENIRQ */
+        tsc2007_xfer(tsc, PWRDOWN);
+}
+
+static u32 tsc2007_calculate_pressure(struct tsc2007 *tsc, struct ts_event *tc)
+{
+        u32 rt = 0;
 
         /* range filtering */
-        if (x == MAX_12BIT)
-                x = 0;
+        if (tc->x == MAX_12BIT)
+                tc->x = 0;
 
-        if (likely(x && z1)) {
+        if (likely(tc->x && tc->z1)) {
                 /* compute touch pressure resistance using equation #1 */
-                rt = z2;
-                rt -= z1;
-                rt *= x;
-                rt *= ts->x_plate_ohms;
-                rt /= z1;
+                rt = tc->z2 - tc->z1;
+                rt *= tc->x;
+                rt *= tsc->x_plate_ohms;
+                rt /= tc->z1;
                 rt = (rt + 2047) >> 12;
-        } else
-                rt = 0;
+        }
+
+        return rt;
+}
+
+static void tsc2007_send_up_event(struct tsc2007 *tsc)
+{
+        struct input_dev *input = tsc->input;
 
-        /* Sample found inconsistent by debouncing or pressure is beyond
-         * the maximum. Don't report it to user space, repeat at least
-         * once more the measurement
+        dev_dbg(&tsc->client->dev, "UP\n");
+
+        input_report_key(input, BTN_TOUCH, 0);
+        input_report_abs(input, ABS_PRESSURE, 0);
+        input_sync(input);
+}
+
+static void tsc2007_work(struct work_struct *work)
+{
+        struct tsc2007 *ts =
+                container_of(to_delayed_work(work), struct tsc2007, work);
+        struct ts_event tc;
+        u32 rt;
+
+        /*
+         * NOTE: We can't rely on the pressure to determine the pen down
+         * state, even though this controller has a pressure sensor.
+         * The pressure value can fluctuate for quite a while after
+         * lifting the pen and in some cases may not even settle at the
+         * expected value.
+         *
+         * The only safe way to check for the pen up condition is in the
+         * work function by reading the pen signal state (it's a GPIO
+         * and IRQ). Unfortunately such callback is not always available,
+         * in that case we have rely on the pressure anyway.
          */
+        if (ts->get_pendown_state) {
+                if (unlikely(!ts->get_pendown_state())) {
+                        tsc2007_send_up_event(ts);
+                        ts->pendown = false;
+                        goto out;
+                }
+
+                dev_dbg(&ts->client->dev, "pen is still down\n");
+        }
+
+        tsc2007_read_values(ts, &tc);
+
+        rt = tsc2007_calculate_pressure(ts, &tc);
         if (rt > MAX_12BIT) {
+                /*
+                 * Sample found inconsistent by debouncing or pressure is
+                 * beyond the maximum. Don't report it to user space,
+                 * repeat at least once more the measurement.
+                 */
                 dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt);
+                goto out;
 
-                hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
-                              HRTIMER_MODE_REL);
-                return;
         }
 
-        /* NOTE: We can't rely on the pressure to determine the pen down
-         * state, even this controller has a pressure sensor.  The pressure
-         * value can fluctuate for quite a while after lifting the pen and
-         * in some cases may not even settle at the expected value.
-         *
-         * The only safe way to check for the pen up condition is in the
-         * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
-         */
         if (rt) {
                 struct input_dev *input = ts->input;
 
@@ -162,102 +202,74 @@ static void tsc2007_send_event(void *tsc)
                         dev_dbg(&ts->client->dev, "DOWN\n");
 
                         input_report_key(input, BTN_TOUCH, 1);
-                        ts->pendown = 1;
+                        ts->pendown = true;
                 }
 
-                input_report_abs(input, ABS_X, x);
-                input_report_abs(input, ABS_Y, y);
+                input_report_abs(input, ABS_X, tc.x);
+                input_report_abs(input, ABS_Y, tc.y);
                 input_report_abs(input, ABS_PRESSURE, rt);
 
                 input_sync(input);
 
                 dev_dbg(&ts->client->dev, "point(%4d,%4d), pressure (%4u)\n",
-                        x, y, rt);
+                        tc.x, tc.y, rt);
+
+        } else if (!ts->get_pendown_state && ts->pendown) {
+                /*
+                 * We don't have callback to check pendown state, so we
+                 * have to assume that since pressure reported is 0 the
+                 * pen was lifted up.
+                 */
+                tsc2007_send_up_event(ts);
+                ts->pendown = false;
         }
 
-        hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
-                        HRTIMER_MODE_REL);
-}
-
-static int tsc2007_read_values(struct tsc2007 *tsc)
-{
-        /* y- still on; turn on only y+ (and ADC) */
-        tsc->tc.y = tsc2007_xfer(tsc, READ_Y);
-
-        /* turn y- off, x+ on, then leave in lowpower */
-        tsc->tc.x = tsc2007_xfer(tsc, READ_X);
-
-        /* turn y+ off, x- on; we'll use formula #1 */
-        tsc->tc.z1 = tsc2007_xfer(tsc, READ_Z1);
-        tsc->tc.z2 = tsc2007_xfer(tsc, READ_Z2);
-
-        /* power down */
-        tsc2007_xfer(tsc, PWRDOWN);
-
-        return 0;
-}
-
-static enum hrtimer_restart tsc2007_timer(struct hrtimer *handle)
-{
-        struct tsc2007 *ts = container_of(handle, struct tsc2007, timer);
-        unsigned long flags;
-
-        spin_lock_irqsave(&ts->lock, flags);
-
-        if (unlikely(!ts->get_pendown_state() && ts->pendown)) {
-                struct input_dev *input = ts->input;
-
-                dev_dbg(&ts->client->dev, "UP\n");
-
-                input_report_key(input, BTN_TOUCH, 0);
-                input_report_abs(input, ABS_PRESSURE, 0);
-                input_sync(input);
-
-                ts->pendown = 0;
+ out:
+        if (ts->pendown)
+                schedule_delayed_work(&ts->work,
+                                      msecs_to_jiffies(TS_POLL_PERIOD));
+        else
                 enable_irq(ts->irq);
-        } else {
-                /* pen is still down, continue with the measurement */
-                dev_dbg(&ts->client->dev, "pen is still down\n");
-
-                tsc2007_read_values(ts);
-                tsc2007_send_event(ts);
-        }
-
-        spin_unlock_irqrestore(&ts->lock, flags);
-
-        return HRTIMER_NORESTART;
 }
 
 static irqreturn_t tsc2007_irq(int irq, void *handle)
 {
         struct tsc2007 *ts = handle;
-        unsigned long flags;
-
-        spin_lock_irqsave(&ts->lock, flags);
 
-        if (likely(ts->get_pendown_state())) {
+        if (!ts->get_pendown_state || likely(ts->get_pendown_state())) {
                 disable_irq_nosync(ts->irq);
-                hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY),
-                                        HRTIMER_MODE_REL);
+                schedule_delayed_work(&ts->work,
+                                      msecs_to_jiffies(TS_POLL_DELAY));
         }
 
         if (ts->clear_penirq)
                 ts->clear_penirq();
 
-        spin_unlock_irqrestore(&ts->lock, flags);
-
         return IRQ_HANDLED;
 }
 
-static int tsc2007_probe(struct i2c_client *client,
-                        const struct i2c_device_id *id)
+static void tsc2007_free_irq(struct tsc2007 *ts)
+{
+        free_irq(ts->irq, ts);
+        if (cancel_delayed_work_sync(&ts->work)) {
+                /*
+                 * Work was pending, therefore we need to enable
+                 * IRQ here to balance the disable_irq() done in the
+                 * interrupt handler.
+                 */
+                enable_irq(ts->irq);
+        }
+}
+
+static int __devinit tsc2007_probe(struct i2c_client *client,
+                                   const struct i2c_device_id *id)
 {
         struct tsc2007 *ts;
         struct tsc2007_platform_data *pdata = pdata = client->dev.platform_data;
         struct input_dev *input_dev;
         int err;
 
-        if (!pdata || !pdata->get_pendown_state) {
+        if (!pdata) {
                 dev_err(&client->dev, "platform data is required!\n");
                 return -EINVAL;
         }
@@ -274,22 +286,15 @@ static int tsc2007_probe(struct i2c_client *client,
         }
 
         ts->client = client;
-        i2c_set_clientdata(client, ts);
-
+        ts->irq = client->irq;
         ts->input = input_dev;
-
-        hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-        ts->timer.function = tsc2007_timer;
-
-        spin_lock_init(&ts->lock);
+        INIT_DELAYED_WORK(&ts->work, tsc2007_work);
 
         ts->model             = pdata->model;
         ts->x_plate_ohms      = pdata->x_plate_ohms;
         ts->get_pendown_state = pdata->get_pendown_state;
         ts->clear_penirq      = pdata->clear_penirq;
 
-        pdata->init_platform_hw();
-
         snprintf(ts->phys, sizeof(ts->phys),
                  "%s/input0", dev_name(&client->dev));
 
@@ -304,9 +309,8 @@ static int tsc2007_probe(struct i2c_client *client,
         input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
         input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);
 
-        tsc2007_read_values(ts);
-
-        ts->irq = client->irq;
+        if (pdata->init_platform_hw)
+                pdata->init_platform_hw();
 
         err = request_irq(ts->irq, tsc2007_irq, 0,
                         client->dev.driver->name, ts);
@@ -315,33 +319,39 @@ static int tsc2007_probe(struct i2c_client *client,
                 goto err_free_mem;
         }
 
+        /* Prepare for touch readings - power down ADC and enable PENIRQ */
+        err = tsc2007_xfer(ts, PWRDOWN);
+        if (err < 0)
+                goto err_free_irq;
+
         err = input_register_device(input_dev);
         if (err)
                 goto err_free_irq;
 
-        dev_info(&client->dev, "registered with irq (%d)\n", ts->irq);
+        i2c_set_clientdata(client, ts);
 
         return 0;
 
  err_free_irq:
-        free_irq(ts->irq, ts);
-        hrtimer_cancel(&ts->timer);
+        tsc2007_free_irq(ts);
+        if (pdata->exit_platform_hw)
+                pdata->exit_platform_hw();
  err_free_mem:
         input_free_device(input_dev);
         kfree(ts);
         return err;
 }
 
-static int tsc2007_remove(struct i2c_client *client)
+static int __devexit tsc2007_remove(struct i2c_client *client)
 {
         struct tsc2007  *ts = i2c_get_clientdata(client);
-        struct tsc2007_platform_data *pdata;
+        struct tsc2007_platform_data *pdata = client->dev.platform_data;
 
-        pdata = client->dev.platform_data;
-        pdata->exit_platform_hw();
+        tsc2007_free_irq(ts);
+
+        if (pdata->exit_platform_hw)
+                pdata->exit_platform_hw();
 
-        free_irq(ts->irq, ts);
-        hrtimer_cancel(&ts->timer);
         input_unregister_device(ts->input);
         kfree(ts);
 
@@ -362,7 +372,7 @@ static struct i2c_driver tsc2007_driver = {
         },
         .id_table       = tsc2007_idtable,
         .probe          = tsc2007_probe,
-        .remove         = tsc2007_remove,
+        .remove         = __devexit_p(tsc2007_remove),
 };
 
 static int __init tsc2007_init(void)