1 files changed, 109 insertions, 53 deletions

diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index ce6f48c695f5..b9b7fc6ff1eb 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -24,6 +24,7 @@
 #include <linux/input.h>
 #include <linux/interrupt.h>
 #include <linux/slab.h>
+#include <linux/gpio.h>
 #include <linux/spi/spi.h>
 #include <linux/spi/ads7846.h>
 #include <asm/irq.h>
@@ -68,6 +69,17 @@ struct ts_event {
         int     ignore;
 };
 
+/*
+ * We allocate this separately to avoid cache line sharing issues when
+ * driver is used with DMA-based SPI controllers (like atmel_spi) on
+ * systems where main memory is not DMA-coherent (most non-x86 boards).
+ */
+struct ads7846_packet {
+        u8                      read_x, read_y, read_z1, read_z2, pwrdown;
+        u16                     dummy;          /* for the pwrdown read */
+        struct ts_event         tc;
+};
+
 struct ads7846 {
         struct input_dev        *input;
         char                    phys[32];
@@ -85,9 +97,7 @@ struct ads7846 {
         u16                     x_plate_ohms;
         u16                     pressure_max;
 
-        u8                      read_x, read_y, read_z1, read_z2, pwrdown;
-        u16                     dummy;          /* for the pwrdown read */
-        struct ts_event         tc;
+        struct ads7846_packet   *packet;
 
         struct spi_transfer     xfer[18];
         struct spi_message      msg[5];
@@ -116,6 +126,7 @@ struct ads7846 {
         void                    *filter_data;
         void                    (*filter_cleanup)(void *data);
         int                     (*get_pendown_state)(void);
+        int                     gpio_pendown;
 };
 
 /* leave chip selected when we're done, for quicker re-select? */
@@ -461,10 +472,11 @@ static ssize_t ads7846_disable_store(struct device *dev,
                                      const char *buf, size_t count)
 {
         struct ads7846 *ts = dev_get_drvdata(dev);
-        char *endp;
-        int i;
+        long i;
+
+        if (strict_strtoul(buf, 10, &i))
+                return -EINVAL;
 
-        i = simple_strtoul(buf, &endp, 10);
         spin_lock_irq(&ts->lock);
 
         if (i)
@@ -491,6 +503,14 @@ static struct attribute_group ads784x_attr_group = {
 
 /*--------------------------------------------------------------------------*/
 
+static int get_pendown_state(struct ads7846 *ts)
+{
+        if (ts->get_pendown_state)
+                return ts->get_pendown_state();
+
+        return !gpio_get_value(ts->gpio_pendown);
+}
+
 /*
  * PENIRQ only kicks the timer.  The timer only reissues the SPI transfer,
  * to retrieve touchscreen status.
@@ -502,16 +522,17 @@ static struct attribute_group ads784x_attr_group = {
 static void ads7846_rx(void *ads)
 {
         struct ads7846          *ts = ads;
+        struct ads7846_packet   *packet = ts->packet;
         unsigned                Rt;
         u16                     x, y, z1, z2;
 
         /* ads7846_rx_val() did in-place conversion (including byteswap) from
          * on-the-wire format as part of debouncing to get stable readings.
          */
-        x = ts->tc.x;
-        y = ts->tc.y;
-        z1 = ts->tc.z1;
-        z2 = ts->tc.z2;
+        x = packet->tc.x;
+        y = packet->tc.y;
+        z1 = packet->tc.z1;
+        z2 = packet->tc.z2;
 
         /* range filtering */
         if (x == MAX_12BIT)
@@ -535,10 +556,10 @@ static void ads7846_rx(void *ads)
          * the maximum. Don't report it to user space, repeat at least
          * once more the measurement
          */
-        if (ts->tc.ignore || Rt > ts->pressure_max) {
+        if (packet->tc.ignore || Rt > ts->pressure_max) {
 #ifdef VERBOSE
                 pr_debug("%s: ignored %d pressure %d\n",
-                        ts->spi->dev.bus_id, ts->tc.ignore, Rt);
+                        ts->spi->dev.bus_id, packet->tc.ignore, Rt);
 #endif
                 hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
                               HRTIMER_MODE_REL);
@@ -550,7 +571,7 @@ static void ads7846_rx(void *ads)
          */
         if (ts->penirq_recheck_delay_usecs) {
                 udelay(ts->penirq_recheck_delay_usecs);
-                if (!ts->get_pendown_state())
+                if (!get_pendown_state(ts))
                         Rt = 0;
         }
 
@@ -631,6 +652,7 @@ static int ads7846_no_filter(void *ads, int data_idx, int *val)
 static void ads7846_rx_val(void *ads)
 {
         struct ads7846 *ts = ads;
+        struct ads7846_packet *packet = ts->packet;
         struct spi_message *m;
         struct spi_transfer *t;
         int val;
@@ -650,7 +672,7 @@ static void ads7846_rx_val(void *ads)
         case ADS7846_FILTER_REPEAT:
                 break;
         case ADS7846_FILTER_IGNORE:
-                ts->tc.ignore = 1;
+                packet->tc.ignore = 1;
                 /* Last message will contain ads7846_rx() as the
                  * completion function.
                  */
@@ -658,7 +680,7 @@ static void ads7846_rx_val(void *ads)
                 break;
         case ADS7846_FILTER_OK:
                 *(u16 *)t->rx_buf = val;
-                ts->tc.ignore = 0;
+                packet->tc.ignore = 0;
                 m = &ts->msg[++ts->msg_idx];
                 break;
         default:
@@ -677,7 +699,7 @@ static enum hrtimer_restart ads7846_timer(struct hrtimer *handle)
 
         spin_lock_irq(&ts->lock);
 
-        if (unlikely(!ts->get_pendown_state() ||
+        if (unlikely(!get_pendown_state(ts) ||
                      device_suspended(&ts->spi->dev))) {
                 if (ts->pendown) {
                         struct input_dev *input = ts->input;
@@ -716,7 +738,7 @@ static irqreturn_t ads7846_irq(int irq, void *handle)
         unsigned long flags;
 
         spin_lock_irqsave(&ts->lock, flags);
-        if (likely(ts->get_pendown_state())) {
+        if (likely(get_pendown_state(ts))) {
                 if (!ts->irq_disabled) {
                         /* The ARM do_simple_IRQ() dispatcher doesn't act
                          * like the other dispatchers:  it will report IRQs
@@ -763,7 +785,6 @@ static void ads7846_disable(struct ads7846 *ts)
         /* we know the chip's in lowpower mode since we always
          * leave it that way after every request
          */
-
 }
 
 /* Must be called with ts->lock held */
@@ -806,9 +827,40 @@ static int ads7846_resume(struct spi_device *spi)
         return 0;
 }
 
+static int __devinit setup_pendown(struct spi_device *spi, struct ads7846 *ts)
+{
+        struct ads7846_platform_data *pdata = spi->dev.platform_data;
+        int err;
+
+        /* REVISIT when the irq can be triggered active-low, or if for some
+         * reason the touchscreen isn't hooked up, we don't need to access
+         * the pendown state.
+         */
+        if (!pdata->get_pendown_state && !gpio_is_valid(pdata->gpio_pendown)) {
+                dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
+                return -EINVAL;
+        }
+
+        if (pdata->get_pendown_state) {
+                ts->get_pendown_state = pdata->get_pendown_state;
+                return 0;
+        }
+
+        err = gpio_request(pdata->gpio_pendown, "ads7846_pendown");
+        if (err) {
+                dev_err(&spi->dev, "failed to request pendown GPIO%d\n",
+                                pdata->gpio_pendown);
+                return err;
+        }
+
+        ts->gpio_pendown = pdata->gpio_pendown;
+        return 0;
+}
+
 static int __devinit ads7846_probe(struct spi_device *spi)
 {
         struct ads7846                  *ts;
+        struct ads7846_packet           *packet;
         struct input_dev                *input_dev;
         struct ads7846_platform_data    *pdata = spi->dev.platform_data;
         struct spi_message              *m;
@@ -833,15 +885,6 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                 return -EINVAL;
         }
 
-        /* REVISIT when the irq can be triggered active-low, or if for some
-         * reason the touchscreen isn't hooked up, we don't need to access
-         * the pendown state.
-         */
-        if (pdata->get_pendown_state == NULL) {
-                dev_dbg(&spi->dev, "no get_pendown_state function?\n");
-                return -EINVAL;
-        }
-
         /* We'd set TX wordsize 8 bits and RX wordsize to 13 bits ... except
          * that even if the hardware can do that, the SPI controller driver
          * may not.  So we stick to very-portable 8 bit words, both RX and TX.
@@ -853,14 +896,16 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                 return err;
 
         ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL);
+        packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL);
         input_dev = input_allocate_device();
-        if (!ts || !input_dev) {
+        if (!ts || !packet || !input_dev) {
                 err = -ENOMEM;
                 goto err_free_mem;
         }
 
         dev_set_drvdata(&spi->dev, ts);
 
+        ts->packet = packet;
         ts->spi = spi;
         ts->input = input_dev;
         ts->vref_mv = pdata->vref_mv;
@@ -893,7 +938,10 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                 ts->filter_data = ts;
         } else
                 ts->filter = ads7846_no_filter;
-        ts->get_pendown_state = pdata->get_pendown_state;
+
+        err = setup_pendown(spi, ts);
+        if (err)
+                goto err_cleanup_filter;
 
         if (pdata->penirq_recheck_delay_usecs)
                 ts->penirq_recheck_delay_usecs =
@@ -929,13 +977,13 @@ static int __devinit ads7846_probe(struct spi_device *spi)
         spi_message_init(m);
 
         /* y- still on; turn on only y+ (and ADC) */
-        ts->read_y = READ_Y(vref);
-        x->tx_buf = &ts->read_y;
+        packet->read_y = READ_Y(vref);
+        x->tx_buf = &packet->read_y;
         x->len = 1;
         spi_message_add_tail(x, m);
 
         x++;
-        x->rx_buf = &ts->tc.y;
+        x->rx_buf = &packet->tc.y;
         x->len = 2;
         spi_message_add_tail(x, m);
 
@@ -947,12 +995,12 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                 x->delay_usecs = pdata->settle_delay_usecs;
 
                 x++;
-                x->tx_buf = &ts->read_y;
+                x->tx_buf = &packet->read_y;
                 x->len = 1;
                 spi_message_add_tail(x, m);
 
                 x++;
-                x->rx_buf = &ts->tc.y;
+                x->rx_buf = &packet->tc.y;
                 x->len = 2;
                 spi_message_add_tail(x, m);
         }
@@ -965,13 +1013,13 @@ static int __devinit ads7846_probe(struct spi_device *spi)
 
         /* turn y- off, x+ on, then leave in lowpower */
         x++;
-        ts->read_x = READ_X(vref);
-        x->tx_buf = &ts->read_x;
+        packet->read_x = READ_X(vref);
+        x->tx_buf = &packet->read_x;
         x->len = 1;
         spi_message_add_tail(x, m);
 
         x++;
-        x->rx_buf = &ts->tc.x;
+        x->rx_buf = &packet->tc.x;
         x->len = 2;
         spi_message_add_tail(x, m);
 
@@ -980,12 +1028,12 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                 x->delay_usecs = pdata->settle_delay_usecs;
 
                 x++;
-                x->tx_buf = &ts->read_x;
+                x->tx_buf = &packet->read_x;
                 x->len = 1;
                 spi_message_add_tail(x, m);
 
                 x++;
-                x->rx_buf = &ts->tc.x;
+                x->rx_buf = &packet->tc.x;
                 x->len = 2;
                 spi_message_add_tail(x, m);
         }
@@ -999,13 +1047,13 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                 spi_message_init(m);
 
                 x++;
-                ts->read_z1 = READ_Z1(vref);
-                x->tx_buf = &ts->read_z1;
+                packet->read_z1 = READ_Z1(vref);
+                x->tx_buf = &packet->read_z1;
                 x->len = 1;
                 spi_message_add_tail(x, m);
 
                 x++;
-                x->rx_buf = &ts->tc.z1;
+                x->rx_buf = &packet->tc.z1;
                 x->len = 2;
                 spi_message_add_tail(x, m);
 
@@ -1014,12 +1062,12 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                         x->delay_usecs = pdata->settle_delay_usecs;
 
                         x++;
-                        x->tx_buf = &ts->read_z1;
+                        x->tx_buf = &packet->read_z1;
                         x->len = 1;
                         spi_message_add_tail(x, m);
 
                         x++;
-                        x->rx_buf = &ts->tc.z1;
+                        x->rx_buf = &packet->tc.z1;
                         x->len = 2;
                         spi_message_add_tail(x, m);
                 }
@@ -1031,13 +1079,13 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                 spi_message_init(m);
 
                 x++;
-                ts->read_z2 = READ_Z2(vref);
-                x->tx_buf = &ts->read_z2;
+                packet->read_z2 = READ_Z2(vref);
+                x->tx_buf = &packet->read_z2;
                 x->len = 1;
                 spi_message_add_tail(x, m);
 
                 x++;
-                x->rx_buf = &ts->tc.z2;
+                x->rx_buf = &packet->tc.z2;
                 x->len = 2;
                 spi_message_add_tail(x, m);
 
@@ -1046,12 +1094,12 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                         x->delay_usecs = pdata->settle_delay_usecs;
 
                         x++;
-                        x->tx_buf = &ts->read_z2;
+                        x->tx_buf = &packet->read_z2;
                         x->len = 1;
                         spi_message_add_tail(x, m);
 
                         x++;
-                        x->rx_buf = &ts->tc.z2;
+                        x->rx_buf = &packet->tc.z2;
                         x->len = 2;
                         spi_message_add_tail(x, m);
                 }
@@ -1065,13 +1113,13 @@ static int __devinit ads7846_probe(struct spi_device *spi)
         spi_message_init(m);
 
         x++;
-        ts->pwrdown = PWRDOWN;
-        x->tx_buf = &ts->pwrdown;
+        packet->pwrdown = PWRDOWN;
+        x->tx_buf = &packet->pwrdown;
         x->len = 1;
         spi_message_add_tail(x, m);
 
         x++;
-        x->rx_buf = &ts->dummy;
+        x->rx_buf = &packet->dummy;
         x->len = 2;
         CS_CHANGE(*x);
         spi_message_add_tail(x, m);
@@ -1085,7 +1133,7 @@ static int __devinit ads7846_probe(struct spi_device *spi)
                         spi->dev.driver->name, ts)) {
                 dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
                 err = -EBUSY;
-                goto err_cleanup_filter;
+                goto err_free_gpio;
         }
 
         err = ads784x_hwmon_register(spi, ts);
@@ -1116,11 +1164,15 @@ static int __devinit ads7846_probe(struct spi_device *spi)
         ads784x_hwmon_unregister(spi, ts);
  err_free_irq:
         free_irq(spi->irq, ts);
+ err_free_gpio:
+        if (ts->gpio_pendown != -1)
+                gpio_free(ts->gpio_pendown);
  err_cleanup_filter:
         if (ts->filter_cleanup)
                 ts->filter_cleanup(ts->filter_data);
  err_free_mem:
         input_free_device(input_dev);
+        kfree(packet);
         kfree(ts);
         return err;
 }
@@ -1140,9 +1192,13 @@ static int __devexit ads7846_remove(struct spi_device *spi)
         /* suspend left the IRQ disabled */
         enable_irq(ts->spi->irq);
 
+        if (ts->gpio_pendown != -1)
+                gpio_free(ts->gpio_pendown);
+
         if (ts->filter_cleanup)
                 ts->filter_cleanup(ts->filter_data);
 
+        kfree(ts->packet);
         kfree(ts);
 
         dev_dbg(&spi->dev, "unregistered touchscreen\n");