HID: ntrig: identify firmware version

};

/*

 * This function converts the 4 byte raw firmware code into

 * a string containing 5 comma separated numbers.

 */

static int ntrig_version_string(unsigned char *raw, char *buf)

{

	__u8 a =  (raw[1] & 0x0e) >> 1;

	__u8 b =  (raw[0] & 0x3c) >> 2;

	__u8 c = ((raw[0] & 0x03) << 3) | ((raw[3] & 0xe0) >> 5);

	__u8 d = ((raw[3] & 0x07) << 3) | ((raw[2] & 0xe0) >> 5);

	__u8 e =   raw[2] & 0x07;

	/*

	 * As yet unmapped bits:

	 * 0b11000000 0b11110001 0b00011000 0b00011000

	 */

	return sprintf(buf, "%u.%u.%u.%u.%u", a, b, c, d, e);

}

static void ntrig_report_version(struct hid_device *hdev)

{

	int ret;

	char buf[20];

	struct usb_device *usb_dev = hid_to_usb_dev(hdev);

	unsigned char *data = kmalloc(8, GFP_KERNEL);

	if (!data)

		goto err_free;

	ret = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),

			      USB_REQ_CLEAR_FEATURE,

			      USB_TYPE_CLASS | USB_RECIP_INTERFACE |

			      USB_DIR_IN,

			      0x30c, 1, data, 8,

			      USB_CTRL_SET_TIMEOUT);

	if (ret == 8) {

		ret = ntrig_version_string(&data[2], buf);

		dev_info(&hdev->dev,

			 "Firmware version: %s (%02x%02x %02x%02x)\n",

			 buf, data[2], data[3], data[4], data[5]);

	}

err_free:

	kfree(data);

}

static ssize_t show_phys_width(struct device *dev,

			       struct device_attribute *attr,

			       char *buf)

	if (report)

		usbhid_submit_report(hdev, report, USB_DIR_OUT);

	ntrig_report_version(hdev);

	ret = sysfs_create_group(&hdev->dev.kobj,

			&ntrig_attribute_group);