Input: ad714x - read the interrupt status registers in a row

The interrupt status registers should be read in row to avoid invalid data.

Alter "read" method for both bus options to allow reading several registers
in a row and make sure we read interrupt status registers properly.

Read sequence saves 50% of bus transactions compared to single register
reads. So use it also for the result registers, which are also located
in a row.

Also update copyright notice.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 32 insertions, 30 deletions

diff --git a/drivers/input/misc/ad714x.c b/drivers/input/misc/ad714x.c
index 2be0366c8123..ca42c7d2a3c7 100644
--- a/drivers/input/misc/ad714x.c
+++ b/drivers/input/misc/ad714x.c
@@ -1,7 +1,7 @@
 /*
  * AD714X CapTouch Programmable Controller driver supporting AD7142/3/7/8/7A
  *
- * Copyright 2009 Analog Devices Inc.
+ * Copyright 2009-2011 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */
@@ -123,6 +123,7 @@ struct ad714x_driver_data {
  * information to integrate all things which will be private data
  * of spi/i2c device
  */
+
 static void ad714x_use_com_int(struct ad714x_chip *ad714x,
                                 int start_stage, int end_stage)
 {
@@ -131,11 +132,11 @@ static void ad714x_use_com_int(struct ad714x_chip *ad714x,
 
         mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
 
-        ad714x->read(ad714x, STG_COM_INT_EN_REG, &data);
+        ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
         data |= 1 << end_stage;
         ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
 
-        ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data);
+        ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
         data &= ~mask;
         ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
 }
@@ -148,11 +149,11 @@ static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
 
         mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
 
-        ad714x->read(ad714x, STG_COM_INT_EN_REG, &data);
+        ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
         data &= ~(1 << end_stage);
         ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
 
-        ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data);
+        ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
         data |= mask;
         ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
 }
@@ -250,13 +251,16 @@ static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
         int i;
 
+        ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
+                        &ad714x->adc_reg[hw->start_stage],
+                        hw->end_stage - hw->start_stage + 1);
+
         for (i = hw->start_stage; i <= hw->end_stage; i++) {
-                ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
                 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
-                                &ad714x->amb_reg[i]);
+                                &ad714x->amb_reg[i], 1);
 
-                ad714x->sensor_val[i] = abs(ad714x->adc_reg[i] -
-                                ad714x->amb_reg[i]);
+                ad714x->sensor_val[i] =
+                        abs(ad714x->adc_reg[i] - ad714x->amb_reg[i]);
         }
 }
 
@@ -419,13 +423,16 @@ static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
         int i;
 
+        ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
+                        &ad714x->adc_reg[hw->start_stage],
+                        hw->end_stage - hw->start_stage + 1);
+
         for (i = hw->start_stage; i <= hw->end_stage; i++) {
-                ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
                 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
-                                &ad714x->amb_reg[i]);
+                                &ad714x->amb_reg[i], 1);
                 if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
-                        ad714x->sensor_val[i] = ad714x->adc_reg[i] -
-                                ad714x->amb_reg[i];
+                        ad714x->sensor_val[i] =
+                                ad714x->adc_reg[i] - ad714x->amb_reg[i];
                 else
                         ad714x->sensor_val[i] = 0;
         }
@@ -570,13 +577,16 @@ static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
         int i;
 
+        ad714x->read(ad714x, CDC_RESULT_S0 + hw->x_start_stage,
+                        &ad714x->adc_reg[hw->x_start_stage],
+                        hw->x_end_stage - hw->x_start_stage + 1);
+
         for (i = hw->x_start_stage; i <= hw->x_end_stage; i++) {
-                ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
                 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
-                                &ad714x->amb_reg[i]);
+                                &ad714x->amb_reg[i], 1);
                 if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
-                        ad714x->sensor_val[i] = ad714x->adc_reg[i] -
-                                ad714x->amb_reg[i];
+                        ad714x->sensor_val[i] =
+                                ad714x->adc_reg[i] - ad714x->amb_reg[i];
                 else
                         ad714x->sensor_val[i] = 0;
         }
@@ -862,7 +872,7 @@ static int ad714x_hw_detect(struct ad714x_chip *ad714x)
 {
         unsigned short data;
 
-        ad714x->read(ad714x, AD714X_PARTID_REG, &data);
+        ad714x->read(ad714x, AD714X_PARTID_REG, &data, 1);
         switch (data & 0xFFF0) {
         case AD7142_PARTID:
                 ad714x->product = 0x7142;
@@ -919,14 +929,12 @@ static void ad714x_hw_init(struct ad714x_chip *ad714x)
                 ad714x->write(ad714x, AD714X_SYSCFG_REG + i,
                         ad714x->hw->sys_cfg_reg[i]);
         for (i = 0; i < SYS_CFGREG_NUM; i++)
-                ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data);
+                ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data, 1);
 
         ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF);
 
         /* clear all interrupts */
-        ad714x->read(ad714x, STG_LOW_INT_STA_REG, &data);
-        ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &data);
-        ad714x->read(ad714x, STG_COM_INT_STA_REG, &data);
+        ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
 }
 
 static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
@@ -936,9 +944,7 @@ static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
 
         mutex_lock(&ad714x->mutex);
 
-        ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state);
-        ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &ad714x->h_state);
-        ad714x->read(ad714x, STG_COM_INT_STA_REG, &ad714x->c_state);
+        ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
 
         for (i = 0; i < ad714x->hw->button_num; i++)
                 ad714x_button_state_machine(ad714x, i);
@@ -1225,8 +1231,6 @@ EXPORT_SYMBOL(ad714x_disable);
 
 int ad714x_enable(struct ad714x_chip *ad714x)
 {
-        unsigned short data;
-
         dev_dbg(ad714x->dev, "%s enter\n", __func__);
 
         mutex_lock(&ad714x->mutex);
@@ -1240,9 +1244,7 @@ int ad714x_enable(struct ad714x_chip *ad714x)
          * otherwise we will get no chance to enter falling-edge irq again
          */
 
-        ad714x->read(ad714x, STG_LOW_INT_STA_REG, &data);
-        ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &data);
-        ad714x->read(ad714x, STG_COM_INT_STA_REG, &data);
+        ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
 
         mutex_unlock(&ad714x->mutex);