gpio: adp5588: get value from data out when dir is out

As discussed here: http://ez.analog.com/message/35852,
the 5587 revC and 5588 revB spec sheets contain a mistake
in the GPIO_DAT_STATx register description.

According to R.Shnell at ADI, as well as my own
observations, it should read:
"GPIO data status (shows GPIO state when read for inputs)".

This commit changes the get value function accordingly.

Signed-off-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 13 insertions, 2 deletions

diff --git a/drivers/gpio/gpio-adp5588.c b/drivers/gpio/gpio-adp5588.c
index 3f190e68f973..7d3c8d942ead 100644
--- a/drivers/gpio/gpio-adp5588.c
+++ b/drivers/gpio/gpio-adp5588.c
@@ -67,9 +67,20 @@ static int adp5588_gpio_get_value(struct gpio_chip *chip, unsigned off)
 {
         struct adp5588_gpio *dev =
             container_of(chip, struct adp5588_gpio, gpio_chip);
+        unsigned bank = ADP5588_BANK(off);
+        unsigned bit = ADP5588_BIT(off);
+        int val;
 
-        return !!(adp5588_gpio_read(dev->client,
-                  GPIO_DAT_STAT1 + ADP5588_BANK(off)) & ADP5588_BIT(off));
+        mutex_lock(&dev->lock);
+
+        if (dev->dir[bank] & bit)
+                val = dev->dat_out[bank];
+        else
+                val = adp5588_gpio_read(dev->client, GPIO_DAT_STAT1 + bank);
+
+        mutex_unlock(&dev->lock);
+
+        return !!(val & bit);
 }
 
 static void adp5588_gpio_set_value(struct gpio_chip *chip,