Merge branches 'x86-alternatives-for-linus', 'x86-fpu-for-linus', 'x86-hwmon-for...

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / gpio / cs5535-gpio.c

diff --git a/drivers/gpio/cs5535-gpio.c b/drivers/gpio/cs5535-gpio.c
index e23c06893d19f62195247220075aafce1cfa75c0..d3e55a0ae92be02e5f46ea7d6f7f82c87e75c807 100644 (file)
--- a/drivers/gpio/cs5535-gpio.c
+++ b/drivers/gpio/cs5535-gpio.c
@@ -56,6 +56,29 @@ static struct cs5535_gpio_chip {
  * registers, see include/linux/cs5535.h.
  */
 
+static void errata_outl(struct cs5535_gpio_chip *chip, u32 val,
+               unsigned int reg)
+{
+       unsigned long addr = chip->base + 0x80 + reg;
+
+       /*
+        * According to the CS5536 errata (#36), after suspend
+        * a write to the high bank GPIO register will clear all
+        * non-selected bits; the recommended workaround is a
+        * read-modify-write operation.
+        *
+        * Don't apply this errata to the edge status GPIOs, as writing
+        * to their lower bits will clear them.
+        */
+       if (reg != GPIO_POSITIVE_EDGE_STS && reg != GPIO_NEGATIVE_EDGE_STS) {
+               if (val & 0xffff)
+                       val |= (inl(addr) & 0xffff); /* ignore the high bits */
+               else
+                       val |= (inl(addr) ^ (val >> 16));
+       }
+       outl(val, addr);
+}
+
 static void __cs5535_gpio_set(struct cs5535_gpio_chip *chip, unsigned offset,
                unsigned int reg)
 {
@@ -64,7 +87,7 @@ static void __cs5535_gpio_set(struct cs5535_gpio_chip *chip, unsigned offset,
                outl(1 << offset, chip->base + reg);
        else
                /* high bank register */
-               outl(1 << (offset - 16), chip->base + 0x80 + reg);
+               errata_outl(chip, 1 << (offset - 16), reg);
 }
 
 void cs5535_gpio_set(unsigned offset, unsigned int reg)
@@ -86,7 +109,7 @@ static void __cs5535_gpio_clear(struct cs5535_gpio_chip *chip, unsigned offset,
                outl(1 << (offset + 16), chip->base + reg);
        else
                /* high bank register */
-               outl(1 << offset, chip->base + 0x80 + reg);
+               errata_outl(chip, 1 << offset, reg);
 }
 
 void cs5535_gpio_clear(unsigned offset, unsigned int reg)