Hi.
I'm working on a driver for STA2X11 GPIO controller who seems to fit best to
the generic mmio driver,
the only problem I have is with the dir register case.
The STA2X11 has 3 registers for dir, one for data, one for set and one for
clear.
The generic-mmio driver has support for this fashion for the dat & set & clear
registers but not for dirout/dirin registers.
I wonder if support for this is generic enough to deserve a patch, if so I'm
willing to quickly add this support, if not, adding a flag such as below, will
allow partly using the generic mmio driver only for set/get and the direction
can be handled outside the driver.
Thanks,
Ramon
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index a4d5eb3..4f91526 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -435,6 +435,7 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev,
#define BGPIOF_BIG_ENDIAN_BYTE_ORDER BIT(3)
#define BGPIOF_READ_OUTPUT_REG_SET BIT(4) /* reg_set stores output value */
#define BGPIOF_NO_OUTPUT BIT(5) /* only input */
+#define BGPIOF_NO_DIRECTION BIT(6)
#endif
diff --git a/drivers/gpio/gpio-mmio.c b/drivers/gpio/gpio-mmio.c
index 935292a..66f6448 100644
--- a/drivers/gpio/gpio-mmio.c
+++ b/drivers/gpio/gpio-mmio.c
@@ -554,6 +554,8 @@ static int bgpio_setup_direction(struct gpio_chip *gc,
gc->direction_input = bgpio_dir_in;
gc->get_direction = bgpio_get_dir;
gc->bgpio_dir_inverted = true;
+ } else if (flags & BGPIOF_NO_DIRECTION) {
+ return 0;
} else {
if (flags & BGPIOF_NO_OUTPUT)
gc->direction_output = bgpio_dir_out_err;
@@ -638,7 +640,7 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev,
if (gc->set == bgpio_set_set &&
!(flags & BGPIOF_UNREADABLE_REG_SET))
gc->bgpio_data = gc->read_reg(gc->reg_set);
- if (gc->reg_dir && !(flags & BGPIOF_UNREADABLE_REG_DIR))
+ if (gc->reg_dir && !(flags & (BGPIOF_UNREADABLE_REG_DIR |
BGPIOF_NO_DIRECTION)))
gc->bgpio_dir = gc->read_reg(gc->reg_dir);
return ret;
