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authorChuanhong Guo <gch981213@gmail.com>2020-03-15 20:13:37 +0800
committerBartosz Golaszewski <bgolaszewski@baylibre.com>2020-03-25 09:50:45 +0100
commitd19d2de61fb131abcd29f7c61d3f168f687bfd6e (patch)
treefda8cb7a01b6d9df22d36c5c8e5b4c1a6feb5dc7 /drivers/gpio/gpio-mmio.c
parentd1ee7e1f5c9191afb69ce46cc7752e4257340a31 (diff)
gpio: mmio: introduce BGPIOF_NO_SET_ON_INPUT
Some gpio controllers ignores pin value writing when that pin is configured as input mode. As a result, bgpio_dir_out should set pin to output before configuring pin values or gpio pin values can't be set up properly. Introduce two variants of bgpio_dir_out: bgpio_dir_out_val_first and bgpio_dir_out_dir_first, and assign direction_output according to a new flag: BGPIOF_NO_SET_ON_INPUT. Signed-off-by: Chuanhong Guo <gch981213@gmail.com> Tested-by: René van Dorst <opensource@vdorst.com> Reviewed-by: Sergio Paracuellos <sergio.paracuellos@gmail.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Diffstat (limited to 'drivers/gpio/gpio-mmio.c')
-rw-r--r--drivers/gpio/gpio-mmio.c23
1 files changed, 19 insertions, 4 deletions
diff --git a/drivers/gpio/gpio-mmio.c b/drivers/gpio/gpio-mmio.c
index f729e3e9e983..b778f33cc6af 100644
--- a/drivers/gpio/gpio-mmio.c
+++ b/drivers/gpio/gpio-mmio.c
@@ -389,12 +389,10 @@ static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio)
return GPIO_LINE_DIRECTION_IN;
}
-static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
+static void bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
{
unsigned long flags;
- gc->set(gc, gpio, val);
-
spin_lock_irqsave(&gc->bgpio_lock, flags);
gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
@@ -405,7 +403,21 @@ static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
gc->write_reg(gc->reg_dir_out, gc->bgpio_dir);
spin_unlock_irqrestore(&gc->bgpio_lock, flags);
+}
+static int bgpio_dir_out_dir_first(struct gpio_chip *gc, unsigned int gpio,
+ int val)
+{
+ bgpio_dir_out(gc, gpio, val);
+ gc->set(gc, gpio, val);
+ return 0;
+}
+
+static int bgpio_dir_out_val_first(struct gpio_chip *gc, unsigned int gpio,
+ int val)
+{
+ gc->set(gc, gpio, val);
+ bgpio_dir_out(gc, gpio, val);
return 0;
}
@@ -538,7 +550,10 @@ static int bgpio_setup_direction(struct gpio_chip *gc,
if (dirout || dirin) {
gc->reg_dir_out = dirout;
gc->reg_dir_in = dirin;
- gc->direction_output = bgpio_dir_out;
+ if (flags & BGPIOF_NO_SET_ON_INPUT)
+ gc->direction_output = bgpio_dir_out_dir_first;
+ else
+ gc->direction_output = bgpio_dir_out_val_first;
gc->direction_input = bgpio_dir_in;
gc->get_direction = bgpio_get_dir;
} else {