gpio/generic: initialize basic_mmio_gpio shadow variables properly

It fixes the issue in gpio-generic that commit fb14921 (gpio/mxc: add
missing initialization of basic_mmio_gpio shadow variables) manged to
fix in gpio-mxc driver, so that other platform specific drivers do not
suffer from the same problem over and over again.

Changes since v1:
* Turn the last parameter of bgpio_init() "bool big_endian" into
  "unsigned long flags" and give those really quirky hardwares a
  chance to tell that reg_set and reg_dir are unreadable.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
[grant.likely: Fix big-endian usage to explicitly set BBGPIOF_BIG_ENDIAN]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 5 insertions, 1 deletions

diff --git a/include/linux/basic_mmio_gpio.h b/include/linux/basic_mmio_gpio.h
index feb912196745..1c504ca5bdb3 100644
--- a/include/linux/basic_mmio_gpio.h
+++ b/include/linux/basic_mmio_gpio.h
@@ -67,6 +67,10 @@ int bgpio_remove(struct bgpio_chip *bgc);
 int bgpio_init(struct bgpio_chip *bgc, struct device *dev,
                unsigned long sz, void __iomem *dat, void __iomem *set,
                void __iomem *clr, void __iomem *dirout, void __iomem *dirin,
-               bool big_endian);
+               unsigned long flags);
+
+#define BGPIOF_BIG_ENDIAN               BIT(0)
+#define BGPIOF_UNREADABLE_REG_SET       BIT(1) /* reg_set is unreadable */
+#define BGPIOF_UNREADABLE_REG_DIR       BIT(2) /* reg_dir is unreadable */
 
 #endif /* __BASIC_MMIO_GPIO_H */