1 files changed, 48 insertions, 34 deletions

diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index fec3b9b22309..e7cabf12c8dc 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -102,6 +102,8 @@ struct ads7846 {
 // FIXME remove "irq_disabled"
         unsigned                irq_disabled:1; /* P: lock */
         unsigned                disabled:1;
+
+        int                     (*get_pendown_state)(void);
 };
 
 /* leave chip selected when we're done, for quicker re-select? */
@@ -175,6 +177,12 @@ struct ser_req {
 static void ads7846_enable(struct ads7846 *ts);
 static void ads7846_disable(struct ads7846 *ts);
 
+static int device_suspended(struct device *dev)
+{
+        struct ads7846 *ts = dev_get_drvdata(dev);
+        return dev->power.power_state.event != PM_EVENT_ON || ts->disabled;
+}
+
 static int ads7846_read12_ser(struct device *dev, unsigned command)
 {
         struct spi_device       *spi = to_spi_device(dev);
@@ -227,8 +235,10 @@ static int ads7846_read12_ser(struct device *dev, unsigned command)
         for (i = 0; i < 6; i++)
                 spi_message_add_tail(&req->xfer[i], &req->msg);
 
+        ts->irq_disabled = 1;
         disable_irq(spi->irq);
         status = spi_sync(spi, &req->msg);
+        ts->irq_disabled = 0;
         enable_irq(spi->irq);
 
         if (req->msg.status)
@@ -333,7 +343,7 @@ static void ads7846_rx(void *ads)
         if (x == MAX_12BIT)
                 x = 0;
 
-        if (x && z1 && ts->spi->dev.power.power_state.event == PM_EVENT_ON) {
+        if (likely(x && z1 && !device_suspended(&ts->spi->dev))) {
                 /* compute touch pressure resistance using equation #2 */
                 Rt = z2;
                 Rt -= z1;
@@ -377,20 +387,10 @@ static void ads7846_rx(void *ads)
                         x, y, Rt, Rt ? "" : " UP");
 #endif
 
-        /* don't retrigger while we're suspended */
         spin_lock_irqsave(&ts->lock, flags);
 
         ts->pendown = (Rt != 0);
-        ts->pending = 0;
-
-        if (ts->spi->dev.power.power_state.event == PM_EVENT_ON) {
-                if (ts->pendown)
-                        mod_timer(&ts->timer, jiffies + TS_POLL_PERIOD);
-                else if (ts->irq_disabled) {
-                        ts->irq_disabled = 0;
-                        enable_irq(ts->spi->irq);
-                }
-        }
+        mod_timer(&ts->timer, jiffies + TS_POLL_PERIOD);
 
         spin_unlock_irqrestore(&ts->lock, flags);
 }
@@ -431,10 +431,25 @@ static void ads7846_timer(unsigned long handle)
         struct ads7846  *ts = (void *)handle;
         int             status = 0;
 
-        ts->msg_idx = 0;
-        status = spi_async(ts->spi, &ts->msg[0]);
-        if (status)
-                dev_err(&ts->spi->dev, "spi_async --> %d\n", status);
+        spin_lock_irq(&ts->lock);
+
+        if (unlikely(ts->msg_idx && !ts->pendown)) {
+                /* measurment cycle ended */
+                if (!device_suspended(&ts->spi->dev)) {
+                        ts->irq_disabled = 0;
+                        enable_irq(ts->spi->irq);
+                }
+                ts->pending = 0;
+                ts->msg_idx = 0;
+        } else {
+                /* pen is still down, continue with the measurement */
+                ts->msg_idx = 0;
+                status = spi_async(ts->spi, &ts->msg[0]);
+                if (status)
+                        dev_err(&ts->spi->dev, "spi_async --> %d\n", status);
+        }
+
+        spin_unlock_irq(&ts->lock);
 }
 
 static irqreturn_t ads7846_irq(int irq, void *handle, struct pt_regs *regs)
@@ -443,7 +458,7 @@ static irqreturn_t ads7846_irq(int irq, void *handle, struct pt_regs *regs)
         unsigned long flags;
 
         spin_lock_irqsave(&ts->lock, flags);
-        if (likely(!ts->irq_disabled && !ts->disabled)) {
+        if (likely(ts->get_pendown_state())) {
                 if (!ts->irq_disabled) {
                         /* REVISIT irq logic for many ARM chips has cloned a
                          * bug wherein disabling an irq in its handler won't
@@ -452,10 +467,7 @@ static irqreturn_t ads7846_irq(int irq, void *handle, struct pt_regs *regs)
                          * that state here.
                          */
                         ts->irq_disabled = 1;
-
                         disable_irq(ts->spi->irq);
-                }
-                if (!ts->pending) {
                         ts->pending = 1;
                         mod_timer(&ts->timer, jiffies);
                 }
@@ -473,20 +485,17 @@ static void ads7846_disable(struct ads7846 *ts)
         if (ts->disabled)
                 return;
 
+        ts->disabled = 1;
+
         /* are we waiting for IRQ, or polling? */
-        if (!ts->pendown) {
-                if (!ts->irq_disabled) {
-                        ts->irq_disabled = 1;
-                        disable_irq(ts->spi->irq);
-                }
+        if (!ts->pending) {
+                ts->irq_disabled = 1;
+                disable_irq(ts->spi->irq);
         } else {
-                /* polling; force a final SPI completion;
-                 * that will clean things up neatly
+                /* the timer will run at least once more, and
+                 * leave everything in a clean state, IRQ disabled
                  */
-                if (!ts->pending)
-                        mod_timer(&ts->timer, jiffies);
-
-                while (ts->pendown || ts->pending) {
+                while (ts->pending) {
                         spin_unlock_irq(&ts->lock);
                         msleep(1);
                         spin_lock_irq(&ts->lock);
@@ -497,7 +506,6 @@ static void ads7846_disable(struct ads7846 *ts)
          * leave it that way after every request
          */
 
-        ts->disabled = 1;
 }
 
 /* Must be called with ts->lock held */
@@ -566,6 +574,11 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                 return -EINVAL;
         }
 
+        if (pdata->get_pendown_state == NULL) {
+                dev_dbg(&spi->dev, "no get_pendown_state function?\n");
+                return -EINVAL;
+        }
+
         /* We'd set the wordsize to 12 bits ... except that some controllers
          * will then treat the 8 bit command words as 12 bits (and drop the
          * four MSBs of the 12 bit result).  Result: inputs must be shifted
@@ -596,6 +609,7 @@ static int __devinit ads7846_probe(struct spi_device *spi)
         ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
         ts->debounce_max = pdata->debounce_max ? : 1;
         ts->debounce_tol = pdata->debounce_tol ? : 10;
+        ts->get_pendown_state = pdata->get_pendown_state;
 
         snprintf(ts->phys, sizeof(ts->phys), "%s/input0", spi->dev.bus_id);
 
@@ -786,8 +800,8 @@ static int __devexit ads7846_remove(struct spi_device *spi)
         device_remove_file(&spi->dev, &dev_attr_vaux);
 
         free_irq(ts->spi->irq, ts);
-        if (ts->irq_disabled)
-                enable_irq(ts->spi->irq);
+        /* suspend left the IRQ disabled */
+        enable_irq(ts->spi->irq);
 
         kfree(ts);