[libgpiod][PATCH v3 05/14] bindings: python: add support for bias flags

[Kent Gibson <warthog618@gmail.com>]

Add support for bias flags in line requests and returning the line bias
setting via a bias accessor.

Based on initial work by Drew Fustini <drew@pdp7.com>.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
---
 bindings/python/gpiodmodule.c | 82 +++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)

diff --git a/bindings/python/gpiodmodule.c b/bindings/python/gpiodmodule.c
index 2f6ef51..4723771 100644
--- a/bindings/python/gpiodmodule.c
+++ b/bindings/python/gpiodmodule.c
@@ -60,6 +60,9 @@ enum {
 	gpiod_LINE_REQ_FLAG_OPEN_DRAIN		= GPIOD_BIT(0),
 	gpiod_LINE_REQ_FLAG_OPEN_SOURCE		= GPIOD_BIT(1),
 	gpiod_LINE_REQ_FLAG_ACTIVE_LOW		= GPIOD_BIT(2),
+	gpiod_LINE_REQ_FLAG_BIAS_DISABLE	= GPIOD_BIT(3),
+	gpiod_LINE_REQ_FLAG_BIAS_PULL_DOWN	= GPIOD_BIT(4),
+	gpiod_LINE_REQ_FLAG_BIAS_PULL_UP	= GPIOD_BIT(5),
 };
 
 enum {
@@ -72,6 +75,13 @@ enum {
 	gpiod_ACTIVE_LOW,
 };
 
+enum {
+	gpiod_BIAS_AS_IS = 1,
+	gpiod_BIAS_DISABLE,
+	gpiod_BIAS_PULL_UP,
+	gpiod_BIAS_PULL_DOWN,
+};
+
 enum {
 	gpiod_RISING_EDGE = 1,
 	gpiod_FALLING_EDGE,
@@ -358,6 +368,34 @@ static PyObject *gpiod_Line_active_state(gpiod_LineObject *self,
 	return ret;
 }
 
+PyDoc_STRVAR(gpiod_Line_bias_doc,
+"bias() -> integer\n"
+"\n"
+"Get the bias setting of this GPIO line.");
+
+static PyObject *gpiod_Line_bias(gpiod_LineObject *self,
+				 PyObject *Py_UNUSED(ignored))
+{
+	int bias;
+
+	if (gpiod_ChipIsClosed(self->owner))
+		return NULL;
+
+	bias = gpiod_line_bias(self->line);
+
+	switch (bias) {
+	case GPIOD_LINE_BIAS_PULL_UP:
+		return Py_BuildValue("I", gpiod_BIAS_PULL_UP);
+	case GPIOD_LINE_BIAS_PULL_DOWN:
+		return Py_BuildValue("I", gpiod_BIAS_PULL_DOWN);
+	case GPIOD_LINE_BIAS_DISABLE:
+		return Py_BuildValue("I", gpiod_BIAS_DISABLE);
+	case GPIOD_LINE_BIAS_AS_IS:
+	default:
+		return Py_BuildValue("I", gpiod_BIAS_AS_IS);
+	}
+}
+
 PyDoc_STRVAR(gpiod_Line_is_used_doc,
 "is_used() -> boolean\n"
 "\n"
@@ -752,6 +790,12 @@ static PyMethodDef gpiod_Line_methods[] = {
 		.ml_flags = METH_NOARGS,
 		.ml_doc = gpiod_Line_active_state_doc,
 	},
+	{
+		.ml_name = "bias",
+		.ml_meth = (PyCFunction)gpiod_Line_bias,
+		.ml_flags = METH_NOARGS,
+		.ml_doc = gpiod_Line_bias_doc,
+	},
 	{
 		.ml_name = "is_used",
 		.ml_meth = (PyCFunction)gpiod_Line_is_used,
@@ -1030,6 +1074,12 @@ static void gpiod_MakeRequestConfig(struct gpiod_line_request_config *conf,
 		conf->flags |= GPIOD_LINE_REQUEST_FLAG_OPEN_SOURCE;
 	if (flags & gpiod_LINE_REQ_FLAG_ACTIVE_LOW)
 		conf->flags |= GPIOD_LINE_REQUEST_FLAG_ACTIVE_LOW;
+	if (flags & gpiod_LINE_REQ_FLAG_BIAS_DISABLE)
+		conf->flags |= GPIOD_LINE_REQUEST_FLAG_BIAS_DISABLE;
+	if (flags & gpiod_LINE_REQ_FLAG_BIAS_PULL_DOWN)
+		conf->flags |= GPIOD_LINE_REQUEST_FLAG_BIAS_PULL_DOWN;
+	if (flags & gpiod_LINE_REQ_FLAG_BIAS_PULL_UP)
+		conf->flags |= GPIOD_LINE_REQUEST_FLAG_BIAS_PULL_UP;
 }
 
 PyDoc_STRVAR(gpiod_LineBulk_request_doc,
@@ -2313,6 +2363,26 @@ static gpiod_ConstDescr gpiod_ConstList[] = {
 		.name = "ACTIVE_LOW",
 		.val = gpiod_ACTIVE_LOW,
 	},
+	{
+		.typeobj = &gpiod_LineType,
+		.name = "BIAS_AS_IS",
+		.val = gpiod_BIAS_AS_IS,
+	},
+	{
+		.typeobj = &gpiod_LineType,
+		.name = "BIAS_DISABLE",
+		.val = gpiod_BIAS_DISABLE,
+	},
+	{
+		.typeobj = &gpiod_LineType,
+		.name = "BIAS_PULL_UP",
+		.val = gpiod_BIAS_PULL_UP,
+	},
+	{
+		.typeobj = &gpiod_LineType,
+		.name = "BIAS_PULL_DOWN",
+		.val = gpiod_BIAS_PULL_DOWN,
+	},
 	{
 		.typeobj = &gpiod_LineEventType,
 		.name = "RISING_EDGE",
@@ -2381,6 +2451,18 @@ static gpiod_ModuleConst gpiod_ModuleConsts[] = {
 		.name = "LINE_REQ_FLAG_ACTIVE_LOW",
 		.value = gpiod_LINE_REQ_FLAG_ACTIVE_LOW,
 	},
+	{
+		.name = "LINE_REQ_FLAG_BIAS_DISABLE",
+		.value = gpiod_LINE_REQ_FLAG_BIAS_DISABLE,
+	},
+	{
+		.name = "LINE_REQ_FLAG_BIAS_PULL_DOWN",
+		.value = gpiod_LINE_REQ_FLAG_BIAS_PULL_DOWN,
+	},
+	{
+		.name = "LINE_REQ_FLAG_BIAS_PULL_UP",
+		.value = gpiod_LINE_REQ_FLAG_BIAS_PULL_UP,
+	},
 	{ }
 };
 
-- 
2.24.0