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>

4 files changed, 49 insertions, 41 deletions

diff --git a/drivers/input/misc/ad714x-i2c.c b/drivers/input/misc/ad714x-i2c.c
index 6c6121865f0e..025417d74ca2 100644
--- a/drivers/input/misc/ad714x-i2c.c
+++ b/drivers/input/misc/ad714x-i2c.c
@@ -1,7 +1,7 @@
 /*
  * AD714X CapTouch Programmable Controller driver (I2C bus)
  *
- * Copyright 2009 Analog Devices Inc.
+ * Copyright 2009-2011 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */
@@ -47,9 +47,10 @@ static int ad714x_i2c_write(struct ad714x_chip *chip,
 }
 
 static int ad714x_i2c_read(struct ad714x_chip *chip,
-                           unsigned short reg, unsigned short *data)
+                           unsigned short reg, unsigned short *data, size_t len)
 {
         struct i2c_client *client = to_i2c_client(chip->dev);
+        int i;
         int error;
 
         chip->xfer_buf[0] = cpu_to_be16(reg);
@@ -58,14 +59,16 @@ static int ad714x_i2c_read(struct ad714x_chip *chip,
                                 sizeof(*chip->xfer_buf));
         if (error >= 0)
                 error = i2c_master_recv(client, (u8 *)chip->xfer_buf,
-                                        sizeof(*chip->xfer_buf));
+                                        len * sizeof(*chip->xfer_buf));
 
         if (unlikely(error < 0)) {
                 dev_err(&client->dev, "I2C read error: %d\n", error);
                 return error;
         }
 
-        *data = be16_to_cpup(chip->xfer_buf);
+        for (i = 0; i < len; i++)
+                data[i] = be16_to_cpu(chip->xfer_buf[i]);
+
         return 0;
 }
 
diff --git a/drivers/input/misc/ad714x-spi.c b/drivers/input/misc/ad714x-spi.c
index 306577dc0b98..875b50811361 100644
--- a/drivers/input/misc/ad714x-spi.c
+++ b/drivers/input/misc/ad714x-spi.c
@@ -1,7 +1,7 @@
 /*
  * AD714X CapTouch Programmable Controller driver (SPI bus)
  *
- * Copyright 2009 Analog Devices Inc.
+ * Copyright 2009-2011 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */
@@ -31,11 +31,12 @@ static int ad714x_spi_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(ad714x_spi_pm, ad714x_spi_suspend, ad714x_spi_resume);
 
 static int ad714x_spi_read(struct ad714x_chip *chip,
-                           unsigned short reg, unsigned short *data)
+                           unsigned short reg, unsigned short *data, size_t len)
 {
         struct spi_device *spi = to_spi_device(chip->dev);
         struct spi_message message;
         struct spi_transfer xfer[2];
+        int i;
         int error;
 
         spi_message_init(&message);
@@ -48,7 +49,7 @@ static int ad714x_spi_read(struct ad714x_chip *chip,
         spi_message_add_tail(&xfer[0], &message);
 
         xfer[1].rx_buf = &chip->xfer_buf[1];
-        xfer[1].len = sizeof(chip->xfer_buf[1]);
+        xfer[1].len = sizeof(chip->xfer_buf[1]) * len;
         spi_message_add_tail(&xfer[1], &message);
 
         error = spi_sync(spi, &message);
@@ -57,7 +58,9 @@ static int ad714x_spi_read(struct ad714x_chip *chip,
                 return error;
         }
 
-        *data = be16_to_cpu(chip->xfer_buf[1]);
+        for (i = 0; i < len; i++)
+                data[i] = be16_to_cpu(chip->xfer_buf[i + 1]);
+
         return 0;
 }
 
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);
 
diff --git a/drivers/input/misc/ad714x.h b/drivers/input/misc/ad714x.h
index d12d14911fc3..3c85455aa66d 100644
--- a/drivers/input/misc/ad714x.h
+++ b/drivers/input/misc/ad714x.h
@@ -1,7 +1,7 @@
 /*
  * AD714X CapTouch Programmable Controller driver (bus interfaces)
  *
- * Copyright 2009 Analog Devices Inc.
+ * Copyright 2009-2011 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */
@@ -18,12 +18,12 @@ struct ad714x_platform_data;
 struct ad714x_driver_data;
 struct ad714x_chip;
 
-typedef int (*ad714x_read_t)(struct ad714x_chip *, unsigned short, unsigned short *);
+typedef int (*ad714x_read_t)(struct ad714x_chip *, unsigned short, unsigned short *, size_t);
 typedef int (*ad714x_write_t)(struct ad714x_chip *, unsigned short, unsigned short);
 
 struct ad714x_chip {
-        unsigned short h_state;
         unsigned short l_state;
+        unsigned short h_state;
         unsigned short c_state;
         unsigned short adc_reg[STAGE_NUM];
         unsigned short amb_reg[STAGE_NUM];