[PATCH v9 3/3] HID: cp2112: Fwnode Support

[Danny Kaehn <kaehndan@gmail.com>]

Support describing the CP2112's I2C and GPIO interfaces in firmware.

I2C and GPIO child nodes can either be children with names "i2c" and
"gpio", or, for ACPI, device nodes with _ADR Zero and One,
respectively.

Additionally, support configuring the I2C bus speed from the
clock-frequency device property.

Signed-off-by: Danny Kaehn <kaehndan@gmail.com>
---
 drivers/hid/hid-cp2112.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c
index 27cadadda7c9..9e327763fd90 100644
--- a/drivers/hid/hid-cp2112.c
+++ b/drivers/hid/hid-cp2112.c
@@ -1234,6 +1234,10 @@ static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	u8 buf[3];
 	struct cp2112_smbus_config_report config;
 	struct gpio_irq_chip *girq;
+	struct i2c_timings timings;
+	struct fwnode_handle *child;
+	u32 addr;
+	const char *name;
 	int ret;
 
 	dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
@@ -1247,6 +1251,17 @@ static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
 
 	mutex_init(&dev->lock);
 
+	device_for_each_child_node(&hdev->dev, child) {
+		name = fwnode_get_name(child);
+		ret = acpi_get_local_address(ACPI_HANDLE_FWNODE(child), &addr);
+
+		if ((name && strcmp("i2c", name) == 0) || (!ret && addr == 0))
+			device_set_node(&dev->adap.dev, child);
+		else if ((name && strcmp("gpio", name)) == 0 ||
+					(!ret && addr == 1))
+			dev->gc.fwnode = child;
+	}
+
 	ret = hid_parse(hdev);
 	if (ret) {
 		hid_err(hdev, "parse failed\n");
@@ -1292,6 +1307,9 @@ static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
 		goto err_power_normal;
 	}
 
+	i2c_parse_fw_timings(&dev->adap.dev, &timings, true);
+
+	config.clock_speed = cpu_to_be32(timings.bus_freq_hz);
 	config.retry_time = cpu_to_be16(1);
 
 	ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
-- 
2.25.1