Commit 98b2b712 authored by Evan Green's avatar Evan Green Committed by Wolfram Sang
Browse files

i2c: i2c-mux-gpio: Enable this driver in ACPI land 



Enable i2c-mux-gpio devices to be defined via ACPI. The idle-state
property translates directly to a fwnode_property_*() call. The child
reg property translates naturally into _ADR in ACPI.

The i2c-parent binding is a relic from the days when the bindings
dictated that all direct children of an I2C controller had to be I2C
devices. These days that's no longer required. The i2c-mux can sit as a
direct child of its parent controller, which is where it makes the most
sense from a hardware description perspective. For the ACPI
implementation we'll assume that's always how the i2c-mux-gpio is
instantiated.

Signed-off-by: default avatarEvan Green <evgreen@chromium.org>
Acked-by: default avatarPeter Rosin <peda@axentia.se>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent 19eb29b0

drivers/i2c/muxes/i2c-mux-gpio.c

+79 −28
Original line number Diff line number Diff line
@@ -49,17 +49,57 @@ static int i2c_mux_gpio_deselect(struct i2c_mux_core *muxc, u32 chan) 
	return 0;

}



#ifdef CONFIG_OF

static int i2c_mux_gpio_probe_dt(struct gpiomux *mux,

#ifdef CONFIG_ACPI



static int i2c_mux_gpio_get_acpi_adr(struct device *dev,

				     struct fwnode_handle *fwdev,

				     unsigned int *adr)



{

	unsigned long long adr64;

	acpi_status status;



	status = acpi_evaluate_integer(ACPI_HANDLE_FWNODE(fwdev),

				       METHOD_NAME__ADR,

				       NULL, &adr64);



	if (!ACPI_SUCCESS(status)) {

		dev_err(dev, "Cannot get address\n");

		return -EINVAL;

	}



	*adr = adr64;

	if (*adr != adr64) {

		dev_err(dev, "Address out of range\n");

		return -ERANGE;

	}



	return 0;

}



#else



static int i2c_mux_gpio_get_acpi_adr(struct device *dev,

				     struct fwnode_handle *fwdev,

				     unsigned int *adr)

{

	return -EINVAL;

}



#endif



static int i2c_mux_gpio_probe_fw(struct gpiomux *mux,

				 struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	struct device_node *np = pdev->dev.of_node;

	struct device_node *adapter_np, *child;

	struct i2c_adapter *adapter;

	struct device_node *np = dev->of_node;

	struct device_node *adapter_np;

	struct i2c_adapter *adapter = NULL;

	struct fwnode_handle *child;

	unsigned *values;

	int i = 0;

	int rc, i = 0;



	if (is_of_node(dev->fwnode)) {

		if (!np)

			return -ENODEV;
@@ -70,14 +110,24 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, 
		}

		adapter = of_find_i2c_adapter_by_node(adapter_np);

		of_node_put(adapter_np);



	} else if (is_acpi_node(dev->fwnode)) {

		/*

		 * In ACPI land the mux should be a direct child of the i2c

		 * bus it muxes.

		 */

		acpi_handle dev_handle = ACPI_HANDLE(dev->parent);



		adapter = i2c_acpi_find_adapter_by_handle(dev_handle);

	}



	if (!adapter)

		return -EPROBE_DEFER;



	mux->data.parent = i2c_adapter_id(adapter);

	put_device(&adapter->dev);



	mux->data.n_values = of_get_child_count(np);



	mux->data.n_values = device_get_child_node_count(dev);

	values = devm_kcalloc(dev,

			      mux->data.n_values, sizeof(*mux->data.values),

			      GFP_KERNEL);
@@ -86,24 +136,25 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, 
		return -ENOMEM;

	}



	for_each_child_of_node(np, child) {

		of_property_read_u32(child, "reg", values + i);

	device_for_each_child_node(dev, child) {

		if (is_of_node(child)) {

			fwnode_property_read_u32(child, "reg", values + i);



		} else if (is_acpi_node(child)) {

			rc = i2c_mux_gpio_get_acpi_adr(dev, child, values + i);

			if (rc)

				return rc;

		}



		i++;

	}

	mux->data.values = values;



	if (of_property_read_u32(np, "idle-state", &mux->data.idle))

	if (fwnode_property_read_u32(dev->fwnode, "idle-state", &mux->data.idle))

		mux->data.idle = I2C_MUX_GPIO_NO_IDLE;



	return 0;

}

#else

static int i2c_mux_gpio_probe_dt(struct gpiomux *mux,

					struct platform_device *pdev)

{

	return 0;

}

#endif



static int i2c_mux_gpio_probe(struct platform_device *pdev)

{
@@ -119,7 +170,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev) 
		return -ENOMEM;



	if (!dev_get_platdata(&pdev->dev)) {

		ret = i2c_mux_gpio_probe_dt(mux, pdev);

		ret = i2c_mux_gpio_probe_fw(mux, pdev);

		if (ret < 0)

			return ret;

	} else {