input: misc: sensor drivers

Sensor drivers for MPU, compass, and pressure.
New features include:
- Improved power management
	- Completely powers off when not in use.
	- Individual axis power control.
	- Auto low power accelerometer.
	- HW motion detection that gets an IRQ only when orientation changes.
- Improved performance
	- Auto detect POR readiness.
	- Auto detect reset/error completion.
	- HW access only when needed.
	- Streamlined execution path.
	- Separate reset control.
	- Runtime changes only affect the device being changed (removed carpet
          bombing global resets and disable/enables).
- Separate sample rate for each device.  A device not enabled doesn't inhibit
  a faster rate for an enabled device.
- Multiple MPU slave devices.
- Auto detection of MPU slave devices and allowing an external driver for a
  slave device to use or not use the MPU.
- External bypass mode.  Any external driver can control and lock the MPU
  I2C master bypass mode.
- Improved FIFO control.  Support for all devices to use the FIFO.
- Separate reporting rate for each device.
- Improved timestamping by taking a timestamp before and after the sample and
  using the average.
- Allows generic class driver for slave devices.  All drivers conform to a
  standard API.
- Automatically handle configuration steps to enable a device and make run-time
  changes.
- Improved debug support and added a debug API.
- Add BMP180 pressure driver.
- Added compass high speed feature where compass doesn't prevent the MPU
  devices from going faster than 100Hz.  Needed for camera.
- Added support for 8kHz Gyro and 1kHz accelerometer.  Needed for camera.
- Added support to populate Android sensor_t structure from kernel data.

Bug 1212893
Bug 1161345
Bug 930909
Bug 1224709
Bug 1058689
Bug 1030747
Bug 980723

Change-Id: Ic0a38f015691cfaca1bc3e72422d5980eddc1265
Signed-off-by: Erik Lilliebjerg <elilliebjerg@nvidia.com>
Signed-off-by: Xiaohui Tao <xtao@nvidia.com>
Reviewed-on: http://git-master/r/210592
(cherry picked from commit 90e7c6b815a591eb0bac120c8b595766f2196ecb)
Reviewed-on: http://git-master/r/216709
Reviewed-by: Mandar Padmawar <mpadmawar@nvidia.com>
Tested-by: Mandar Padmawar <mpadmawar@nvidia.com>

1 files changed, 296 insertions, 2 deletions

diff --git a/include/linux/mpu.h b/include/linux/mpu.h
index 1f78833c30f5..3f303da8266a 100644
--- a/include/linux/mpu.h
+++ b/include/linux/mpu.h
@@ -1,5 +1,6 @@
 /*
 * Copyright (C) 2012 Invensense, Inc.
+* Copyright (c) 2013, NVIDIA CORPORATION.  All rights reserved.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
@@ -47,8 +48,19 @@
 *		  data defined by dbg_dat
 *		- A read to dbg_dat initiates an I2C read transaction
 *		  to the device register defined by dbg_reg.
+*	dbg_i2c_addr = I2C device address
+*		- if set to 0 (default) the MPU I2C address is used.
+*		- other devices can be accessed by setting this to the
+*		  that device I2C address.  When used after enabling
+*		  bypass mode, devices behind the MPU can be accessed.
+*	aux_dbg = write 1 to spew auxiliary port register dumps after
+*		  after each external driver call.
+*		  Write 0 to disable the spew.
+*		  Writing anything takes a snapshot of the registers.
+*		  Therefore, a write of 0 can take snapshots whenever
+*		  without the external driver call spew.
 **********************************************************************/
-#define	DEBUG_SYSFS_INTERFACE		0
+#define	DEBUG_SYSFS_INTERFACE		1
 
 /* Mount maxtices for mount orientation.
  * MTMAT_XXX_CCW_YYY
@@ -251,7 +263,6 @@ enum ext_slave_bus {
 	EXT_SLAVE_BUS_SECONDARY = 1
 };
 
-
 /**
  *  struct ext_slave_platform_data - Platform data for mpu3050 and mpu6050
  *  slave devices
@@ -358,6 +369,12 @@ struct ext_slave_descr {
 	struct ext_slave_read_trigger *trigger;
 };
 
+
+#define NVI_CONFIG_BOOT_AUTO		(0) /* auto detect connection to MPU */
+#define NVI_CONFIG_BOOT_MPU		(1) /* connected to MPU */
+#define NVI_CONFIG_BOOT_EXTERNAL	(2) /* connected to host */
+#define NVI_CONFIG_BOOT_MASK		(0x03)
+
 /**
  * struct mpu_platform_data - Platform data for the mpu driver
  * @int_config:		Bits [7:3] of the int config register.
@@ -367,6 +384,8 @@ struct ext_slave_descr {
  * @sec_slave_id:       id of the secondary slave device
  * @secondary_i2c_address: secondary device's i2c address
  * @secondary_orientation: secondary device's orientation matrix
+ * @config: the selection determines the device behavior.
+ *          Select from the NVI_CONFIG_BOOT_ defines.
  *
  * Contains platform specific information on how to configure the MPU3050 to
  * work on this platform.  The orientation matricies are 3x3 rotation matricies
@@ -384,6 +403,281 @@ struct mpu_platform_data {
 	__u8 secondary_read_reg;
 	__s8 secondary_orientation[9];
 	__u8 key[16];
+	__u8 config;
+};
+
+/**
+ * struct nvi_mpu_port: Allows an external driver to use the MPU
+ *    auxiliary I2C master by providing the details for the I2C
+ *    polling of a device connected to the MPU.
+ * - addr: The 6:0 I2C address of the device connected to
+ *      the MPU.
+ *      7:7 = 0 if the port is to do write transactions.
+ *          = 1 if the port is to do read transactions.
+ * - reg: The device register the I2C transaction will
+ *      use.
+ * - ctrl: The number of consecutive registers to read in
+ *      3:0. If the port is to do write transactions then this
+ *      value must be 1.  See MPU documentation for the other
+ *      bits in I2C_SLVx_CTRL that can be applied by this byte.
+ * - data_out: The data byte written if the port is configured
+ *      to do writes (addr 7:7 = 0).
+ * - delay_ms: The polling delay time between I2C transactions
+ *      in ms.  Note that the MPU HW only supports one delay
+ *      time so the longest delay of all the MPU ports enabled
+ *      is used.
+ * - delay_us: The delay at which the read data is reported.
+ * - shutdown_bypass: set if a connection to the host is needed
+ *      when the system is shutdown.  The MPU API will be
+ *      disabled as part of its shutdown but it will enable the
+ *      bypass if this is true.
+ * - *handler: The pointer to the function called when the data
+ *      is available.  This can be NULL if the port is
+ *      configured for write transactions.
+ *      The function is called with the following parameters:
+ *      - *data: The pointer to the data to read.
+ *      - length: The number of bytes to be read (same value as
+ *           length above).
+ *      - timestamp: The timestamp of when the data was polled.
+ *      - *pointer: A generic pointer defined next below.  Note
+ *           that this can be NULL if this will be a write I2C
+ *           transaction.
+ * - *ext_driver: A generic pointer that can be used by the
+ *      external driver.  Note that this is specifically for the
+ *      external driver and not used by the MPU.
+ */
+struct nvi_mpu_port {
+	u8 addr;
+	u8 reg;
+	u8 ctrl;
+	u8 data_out;
+	unsigned int delay_ms;
+	unsigned long delay_us;
+	bool shutdown_bypass;
+	void (*handler)(u8 *data, unsigned int len,
+			long long timestamp, void *ext_driver);
+	void *ext_driver;
 };
 
+/**
+ * Expected use of the nvi_mpu_ routines are as follows:
+ * - nvi_mpu_dev_valid: Use to validate whether a device is
+ *      connected to the MPU.
+ * - nvi_mpu_port_alloc: Request a connection to the device.  If
+ *      successful, a port number will be returned to identify
+ *      the connection.  The port number is then used for all
+ *      further communication with the connection.
+ * - nvi_mpu_port_free: Use to close the port connection.
+ * - nvi_mpu_enable: Use to enable/disable a port.
+ *      The enable and FIFO enable is disabled by default so
+ *      this will be required after a port is assigned.
+ * - nvi_mpu_delay_us: Use to set the sampling rate in
+ *      microseconds.  The fastest rate of all the enabled MPU
+ *      devices will be used that does not exceed the
+ *      nvi_mpu_delay_ms setting of an enabled device.
+ * - nvi_mpu_delay_ms: Use to change the port polling delay at
+ *      runtime. There is only one HW delay so the delay used
+ *      will be the longest delay of all the enabled ports.
+ *      This is separate from the sampling rate
+ *      (nvi_mpu_delay_us).  See function notes below.
+ * - nvi_mpu_data_out: Use to change the data written at runtime
+ *      for ports that are configured as I2C write transactions.
+ * - nvi_mpu_bypass request/release: Use to connect/disconnect
+ *      the MPU host from the device.  When bypass is enabled,
+ *      the connection from the device to the MPU will then be
+ *      connected to the host (that the MPU is connected to).
+ *      This is a global connection switch affecting all ports
+ *      so a mechanism is in place of whether the request is
+ *      honored or not.  See the funtion notes for
+ *      nvi_mpu_bypass_request.
+ */
+
+/**
+ * Use to validate a device connected to the MPU I2C master.
+ * The function works by doing a single byte read or write to
+ * the device and detecting a NACK.  Typically, the call would
+ * be set up to read a byte ID of the device.
+ * @param struct nvi_mpu_port *nmp
+ *           Only the following is needed in nmp:
+ *           - addr
+ *           - reg
+ *           - ctrl
+ *           - data_out if a write transaction
+ * @param *val: pointer for read data.  Can be NULL if write.
+ * @return int error
+ *            Possible return value or errors are:
+ *            - 0: device is connected to MPU.
+ *            - -EAGAIN: MPU is not initialized yet.
+ *            - -EPERM: MPU is shutdown.  MPU API won't be
+ *                 available until a system restart.
+ *            - -EBUSY: MPU is busy with another request.
+ *            - -ENODEV: The device is not connected to the MPU.
+ *            - -EINVAL: Problem with input parameters.
+ *            - -EIO: The device is connected but responded with
+ *                 a NACK.
+ */
+int nvi_mpu_dev_valid(struct nvi_mpu_port *nmp, u8 *data);
+
+/**
+ * Request a port.
+ * @param struct nvi_mpu_port *nmp
+ *           - addr: device I2C address 6:0.
+ *                7:7 = 0 if the port is to do writes.
+ *                7:7 = 1 if the port is to do reads.
+ *           - reg: the starting register to write or read.
+ *           - ctrl: number of bytes to read.  Use 1 if port
+ *                is configured to do writes.
+ *           - data_out: only valid if port is configured to do
+ *                writes.
+ *           - delay: polling delay
+ *           - handler: function to call when data is read. This
+ *                should be NULL if the port is configured to do
+ *                writes.
+ *           - ext_driver: this pointer is passed in handler for
+ *                use by external driver.  This should be NULL
+ *                if the port is configured for writes.
+ * @return int error/port id
+ *            if return >= 0 then this is the port ID.  The ID
+ *            will have a value of 0 to 3 (HW has 4 ports).
+ *            Possible errors are:
+ *            - -EAGAIN: MPU is not initialized yet.
+ *            - -EPERM: MPU is shutdown.  MPU API won't be
+ *                 available until a system restart.
+ *            - -EBUSY: MPU is busy with another request.
+ *            - -ENODEV: A port is not available.  The only way
+ *                 to resolve this error is for a port to be
+ *                 freed.
+ *            - -EINVAL: Problem with input parameters.
+ */
+int nvi_mpu_port_alloc(struct nvi_mpu_port *nmp);
+
+/**
+ * Remove a port.
+ * @param port
+ * @return int error
+ *            Possible errors are:
+ *            - -EAGAIN: MPU is not initialized yet.
+ *            - -EPERM: MPU is shutdown.  MPU API won't be
+ *                 available until a system restart.
+ *            - -EBUSY: MPU is busy with another request.
+ *            - -EINVAL: Problem with input parameters.
+ */
+int nvi_mpu_port_free(int port);
+
+/**
+ * Enable/disable a port.
+ * @param port
+ * @param enable
+ * @return int error
+ *            Possible errors are:
+ *            - -EAGAIN: MPU is not initialized yet.
+ *            - -EPERM: MPU is shutdown.  MPU API won't be
+ *                 available until a system restart.
+ *            - -EBUSY: MPU is busy with another request.
+ *            - -EINVAL: Problem with input parameters.
+ */
+int nvi_mpu_enable(int port, bool enable, bool fifo_enable);
+
+/**
+ * Use to change the ports sampling delay in microseconds. The
+ * hardware only supports one sampling rate so the shortest time
+ * is used among all enabled ports, accelerometer, and gyro. If
+ * the requested rate is longer than the actual rate and the
+ * port is configured for reads, the data will be reported at
+ * the requested rate skipping the data polled at the faster
+ * rate.  Setting this to zero causes other enabled devices to
+ * determine the sampling rate.  If there are no other enabled
+ * devices, then the MPU default rate is used.
+ * @param port
+ * @param delay_us
+ * @return int error
+ *            Possible errors are:
+ *            - -EAGAIN: MPU is not initialized yet.
+ *            - -EPERM: MPU is shutdown.  MPU API won't be
+ *                 available until a system restart.
+ *            - -EBUSY: MPU is busy with another request.
+ *            - -EINVAL: Problem with input parameters.
+ */
+int nvi_mpu_delay_us(int port, unsigned long delay_us);
+
+/**
+ * Use to change the ports polling delay in milliseconds.
+ * A delay value of 0 disables the delay for that port.  The
+ * hardware only supports one delay value so the largest request
+ * of all the enabled ports is used. The polling delay is in
+ * addition to the sampling delay (nvi_mpu_delay_us).  This is
+ * typically used to guarantee a delay after an I2C write to a
+ * device to allow the device to process the request and be read
+ * by another port before another write at the sampling delay.
+ *
+ * @param port
+ * @param delay_ms
+ * @return int error/delay used or 0 if request is to disable
+ *            and is successful.
+ *            Possible errors are:
+ *            - -EAGAIN: MPU is not initialized yet.
+ *            - -EPERM: MPU is shutdown.  MPU API won't be
+ *                 available until a system restart.
+ *            - -EBUSY: MPU is busy with another request.
+ *            - -EINVAL: Problem with input parameters.
+ */
+int nvi_mpu_delay_ms(int port, u8 delay_ms);
+
+/**
+ * Use to change the data written to the sensor.
+ * @param port
+ * @param data_out is the new data to be written
+ * @return int error
+ *            Possible errors are:
+ *            - -EAGAIN: MPU is not initialized yet.
+ *            - -EPERM: MPU is shutdown.  MPU API won't be
+ *                 available until a system restart.
+ *            - -EBUSY: MPU is busy with another request.
+ *            - -EINVAL: Problem with input parameters.
+ */
+int nvi_mpu_data_out(int port, u8 data_out);
+
+/**
+ * Enable/disable the MPU bypass mode.  When enabled, the MPU
+ * will connect its auxiliary I2C ports to the host.  This is
+ * typically used to initialize a device that requires more I2C
+ * transactions than the automated port polling can offer.
+ * EVERY nvi_mpu_bypass_request call must be balanced with a
+ * nvi_mpu_bypass_release call!
+ * A bypass request does not need a following ~enable call.  The
+ * release call will automatically handle the correct bypass
+ * enable setting. The request locks the bypass setting if
+ * successful.  The release unlocks and restores the setting if
+ * need be.  Although odd, the purpose of the request call with
+ * the enable cleared to false is to allow an external driver to
+ * access its device that would normally conflict with a device
+ * behind the MPU.  Note that this call must not be a permanent
+ * solution, i.e. delayed or no release call.
+ * When the MPU is in a shutdown state the return error will be
+ * -EPERM and bypass will be enabled to allow access from the
+ * host to the devices connected to the MPU for their own
+ * shutdown needs.
+ * @param enable
+ * @return int error: calls that return with an error must not
+ *            be balanced with a release call.
+ *            Possible errors are:
+ *            - -EAGAIN: MPU is not initialized yet.
+ *            - -EPERM: MPU is shutdown.  MPU API won't be
+ *                 available until a system restart.
+ *            - -EBUSY: MPU is busy with another request.
+ */
+int nvi_mpu_bypass_request(bool enable);
+
+/**
+ * See the nvi_mpu_bypass_request notes.
+ * @return int error: calls that return with an error must be
+ *            tried again.
+ *            Possible errors are:
+ *            - -EAGAIN: MPU is not initialized yet.
+ *            - -EPERM: MPU is shutdown.  MPU API won't be
+ *                 available until a system restart.
+ *            - -EBUSY: MPU is busy with another request.
+ */
+int nvi_mpu_bypass_release(void);
+
 #endif	/* __MPU_H_ */