drivers/pinctrl/pinctrl-generic-mux.c

Source file repositories/reference/linux-study-clean/drivers/pinctrl/pinctrl-generic-mux.c

File Facts

System
Linux kernel
Corpus path
drivers/pinctrl/pinctrl-generic-mux.c
Extension
.c
Size
4715 bytes
Lines
185
Domain
Driver Families
Bucket
drivers/pinctrl
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct mux_pin_function {
	struct mux_state *mux_state;
};

struct mux_pinctrl {
	struct device *dev;
	struct pinctrl_dev *pctl;

	/* mutex protect [pinctrl|pinmux]_generic functions */
	struct mutex lock;
};

static int
mux_pinmux_dt_node_to_map(struct pinctrl_dev *pctldev,
			  struct device_node *np_config,
			  struct pinctrl_map **maps, unsigned int *num_maps)
{
	unsigned int num_reserved_maps = 0;
	struct mux_pin_function *function;
	const char **group_names;
	int ret;

	function = devm_kzalloc(pctldev->dev, sizeof(*function), GFP_KERNEL);
	if (!function)
		return -ENOMEM;

	group_names = devm_kcalloc(pctldev->dev, 1, sizeof(*group_names), GFP_KERNEL);
	if (!group_names)
		return -ENOMEM;

	function->mux_state = devm_mux_state_get_from_np(pctldev->dev, NULL, np_config);
	if (IS_ERR(function->mux_state))
		return PTR_ERR(function->mux_state);

	ret = pinctrl_generic_to_map(pctldev, np_config, np_config, maps,
				     num_maps, &num_reserved_maps, group_names,
				     0, &np_config->name, NULL, 0);

	if (ret)
		return ret;

	ret = pinmux_generic_add_function(pctldev, np_config->name, group_names,
					  1, function);
	if (ret < 0) {
		pinctrl_utils_free_map(pctldev, *maps, *num_maps);
		return ret;
	}

	return 0;
}

static const struct pinctrl_ops mux_pinctrl_ops = {
	.get_groups_count = pinctrl_generic_get_group_count,
	.get_group_name = pinctrl_generic_get_group_name,
	.get_group_pins = pinctrl_generic_get_group_pins,
	.dt_node_to_map = mux_pinmux_dt_node_to_map,
	.dt_free_map = pinctrl_utils_free_map,
};

static int mux_pinmux_set_mux(struct pinctrl_dev *pctldev,
			      unsigned int func_selector,
			      unsigned int group_selector)
{
	struct mux_pinctrl *mpctl = pinctrl_dev_get_drvdata(pctldev);
	const struct function_desc *function;
	struct mux_pin_function *func;
	int ret;

	guard(mutex)(&mpctl->lock);

	function = pinmux_generic_get_function(pctldev, func_selector);
	func = function->data;

	ret = mux_state_select(func->mux_state);
	if (ret)
		return ret;

	return 0;
}

static void mux_pinmux_release_mux(struct pinctrl_dev *pctldev,
				   unsigned int func_selector,
				   unsigned int group_selector)
{
	struct mux_pinctrl *mpctl = pinctrl_dev_get_drvdata(pctldev);
	const struct function_desc *function;
	struct mux_pin_function *func;

	guard(mutex)(&mpctl->lock);

Annotation

Implementation Notes