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-rw-r--r--Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt15
-rw-r--r--Documentation/devicetree/bindings/staging/imx-drm/fsl-imx-drm.txt41
-rwxr-xr-xDocumentation/hid/hid-sensor.txt140
3 files changed, 196 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt
new file mode 100644
index 000000000000..801d58cb6d4d
--- /dev/null
+++ b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt
@@ -0,0 +1,15 @@
+* Freescale i.MX28 LRADC device driver
+
+Required properties:
+- compatible: Should be "fsl,imx28-lradc"
+- reg: Address and length of the register set for the device
+- interrupts: Should contain the LRADC interrupts
+
+Examples:
+
+ lradc@80050000 {
+ compatible = "fsl,imx28-lradc";
+ reg = <0x80050000 0x2000>;
+ interrupts = <10 14 15 16 17 18 19
+ 20 21 22 23 24 25>;
+ };
diff --git a/Documentation/devicetree/bindings/staging/imx-drm/fsl-imx-drm.txt b/Documentation/devicetree/bindings/staging/imx-drm/fsl-imx-drm.txt
new file mode 100644
index 000000000000..07654f0338b6
--- /dev/null
+++ b/Documentation/devicetree/bindings/staging/imx-drm/fsl-imx-drm.txt
@@ -0,0 +1,41 @@
+Freescale i.MX IPUv3
+====================
+
+Required properties:
+- compatible: Should be "fsl,<chip>-ipu"
+- reg: should be register base and length as documented in the
+ datasheet
+- interrupts: Should contain sync interrupt and error interrupt,
+ in this order.
+- #crtc-cells: 1, See below
+
+example:
+
+ipu: ipu@18000000 {
+ #crtc-cells = <1>;
+ compatible = "fsl,imx53-ipu";
+ reg = <0x18000000 0x080000000>;
+ interrupts = <11 10>;
+};
+
+Parallel display support
+========================
+
+Required properties:
+- compatible: Should be "fsl,imx-parallel-display"
+- crtc: the crtc this display is connected to, see below
+Optional properties:
+- interface_pix_fmt: How this display is connected to the
+ crtc. Currently supported types: "rgb24", "rgb565"
+- edid: verbatim EDID data block describing attached display.
+- ddc: phandle describing the i2c bus handling the display data
+ channel
+
+example:
+
+display@di0 {
+ compatible = "fsl,imx-parallel-display";
+ edid = [edid-data];
+ crtc = <&ipu 0>;
+ interface-pix-fmt = "rgb24";
+};
diff --git a/Documentation/hid/hid-sensor.txt b/Documentation/hid/hid-sensor.txt
new file mode 100755
index 000000000000..948b0989c433
--- /dev/null
+++ b/Documentation/hid/hid-sensor.txt
@@ -0,0 +1,140 @@
+
+HID Sensors Framework
+======================
+HID sensor framework provides necessary interfaces to implement sensor drivers,
+which are connected to a sensor hub. The sensor hub is a HID device and it provides
+a report descriptor conforming to HID 1.12 sensor usage tables.
+
+Description from the HID 1.12 "HID Sensor Usages" specification:
+"Standardization of HID usages for sensors would allow (but not require) sensor
+hardware vendors to provide a consistent Plug And Play interface at the USB boundary,
+thereby enabling some operating systems to incorporate common device drivers that
+could be reused between vendors, alleviating any need for the vendors to provide
+the drivers themselves."
+
+This specification describes many usage IDs, which describe the type of sensor
+and also the individual data fields. Each sensor can have variable number of
+data fields. The length and order is specified in the report descriptor. For
+example a part of report descriptor can look like:
+
+ INPUT(1)[INPUT]
+ ..
+ Field(2)
+ Physical(0020.0073)
+ Usage(1)
+ 0020.045f
+ Logical Minimum(-32767)
+ Logical Maximum(32767)
+ Report Size(8)
+ Report Count(1)
+ Report Offset(16)
+ Flags(Variable Absolute)
+..
+..
+
+The report is indicating "sensor page (0x20)" contains an accelerometer-3D (0x73).
+This accelerometer-3D has some fields. Here for example field 2 is motion intensity
+(0x045f) with a logical minimum value of -32767 and logical maximum of 32767. The
+order of fields and length of each field is important as the input event raw
+data will use this format.
+
+
+Implementation
+=================
+
+This specification defines many different types of sensors with different sets of
+data fields. It is difficult to have a common input event to user space applications,
+for different sensors. For example an accelerometer can send X,Y and Z data, whereas
+an ambient light sensor can send illumination data.
+So the implementation has two parts:
+- Core hid driver
+- Individual sensor processing part (sensor drivers)
+
+Core driver
+-----------
+The core driver registers (hid-sensor-hub) registers as a HID driver. It parses
+report descriptors and identifies all the sensors present. It adds an MFD device
+with name HID-SENSOR-xxxx (where xxxx is usage id from the specification).
+For example
+HID-SENSOR-200073 is registered for an Accelerometer 3D driver.
+So if any driver with this name is inserted, then the probe routine for that
+function will be called. So an accelerometer processing driver can register
+with this name and will be probed if there is an accelerometer-3D detected.
+
+The core driver provides a set of APIs which can be used by the processing
+drivers to register and get events for that usage id. Also it provides parsing
+functions, which get and set each input/feature/output report.
+
+Individual sensor processing part (sensor drivers)
+-----------
+The processing driver will use an interface provided by the core driver to parse
+the report and get the indexes of the fields and also can get events. This driver
+can use IIO interface to use the standard ABI defined for a type of sensor.
+
+
+Core driver Interface
+=====================
+
+Callback structure:
+Each processing driver can use this structure to set some callbacks.
+ int (*suspend)(..): Callback when HID suspend is received
+ int (*resume)(..): Callback when HID resume is received
+ int (*capture_sample)(..): Capture a sample for one of its data fields
+ int (*send_event)(..): One complete event is received which can have
+ multiple data fields.
+
+Registration functions:
+int sensor_hub_register_callback(struct hid_sensor_hub_device *hsdev,
+ u32 usage_id,
+ struct hid_sensor_hub_callbacks *usage_callback):
+
+Registers callbacks for an usage id. The callback functions are not allowed
+to sleep.
+
+
+int sensor_hub_remove_callback(struct hid_sensor_hub_device *hsdev,
+ u32 usage_id):
+
+Removes callbacks for an usage id.
+
+
+Parsing function:
+int sensor_hub_input_get_attribute_info(struct hid_sensor_hub_device *hsdev,
+ u8 type,
+ u32 usage_id, u32 attr_usage_id,
+ struct hid_sensor_hub_attribute_info *info);
+
+A processing driver can look for some field of interest and check if it exists
+in a report descriptor. If it exists it will store necessary information
+so that fields can be set or get individually.
+These indexes avoid searching every time and getting field index to get or set.
+
+
+Set Feature report
+int sensor_hub_set_feature(struct hid_sensor_hub_device *hsdev, u32 report_id,
+ u32 field_index, s32 value);
+
+This interface is used to set a value for a field in feature report. For example
+if there is a field report_interval, which is parsed by a call to
+sensor_hub_input_get_attribute_info before, then it can directly set that individual
+field.
+
+
+int sensor_hub_get_feature(struct hid_sensor_hub_device *hsdev, u32 report_id,
+ u32 field_index, s32 *value);
+
+This interface is used to get a value for a field in input report. For example
+if there is a field report_interval, which is parsed by a call to
+sensor_hub_input_get_attribute_info before, then it can directly get that individual
+field value.
+
+
+int sensor_hub_input_attr_get_raw_value(struct hid_sensor_hub_device *hsdev,
+ u32 usage_id,
+ u32 attr_usage_id, u32 report_id);
+
+This is used to get a particular field value through input reports. For example
+accelerometer wants to poll X axis value, then it can call this function with
+the usage id of X axis. HID sensors can provide events, so this is not necessary
+to poll for any field. If there is some new sample, the core driver will call
+registered callback function to process the sample.