Device Registration Services
[Driver Development API]

Data Structures
struct	rtdm_operations
	Device operations. More...
struct	rtdm_dev_context
	Device context. More...
struct	rtdm_device
	RTDM device. More...
Device Flags
Static flags describing a RTDM device
#define	RTDM_EXCLUSIVE   0x0001
	If set, only a single instance of the device can be requested by an application.
#define	RTDM_NAMED_DEVICE   0x0010
	If set, the device is addressed via a clear-text name.
#define	RTDM_PROTOCOL_DEVICE   0x0020
	If set, the device is addressed via a combination of protocol ID and socket type.
#define	RTDM_DEVICE_TYPE_MASK   0x00F0
	Mask selecting the device type.
Context Flags
Dynamic flags describing the state of an open RTDM device (bit numbers)
#define	RTDM_CREATED_IN_NRT   0
	Set by RTDM if the device instance was created in non-real-time context.
#define	RTDM_CLOSING   1
	Set by RTDM when the device is being closed.
#define	RTDM_FORCED_CLOSING   2
	Set by RTDM if the device has to be closed regardless of possible pending locks held by other users.
#define	RTDM_USER_CONTEXT_FLAG   8
	Lowest bit number the driver developer can use freely.
Driver Versioning
Current revisions of RTDM structures, encoding of driver versions. See API Versioning for the interface revision.
#define	RTDM_DEVICE_STRUCT_VER   3
	Version of struct rtdm_device.
#define	RTDM_CONTEXT_STRUCT_VER   3
	Version of struct rtdm_dev_context.
#define	RTDM_SECURE_DEVICE   0x80000000
	Flag indicating a secure variant of RTDM (not supported here).
#define	RTDM_DRIVER_VER(major, minor, patch)   (((major & 0xFF) << 16) | ((minor & 0xFF) << 8) | (patch & 0xFF))
	Version code constructor for driver revisions.
#define	RTDM_DRIVER_MAJOR_VER(ver)   (((ver) >> 16) & 0xFF)
	Get major version number from driver revision code.
#define	RTDM_DRIVER_MINOR_VER(ver)   (((ver) >> 8) & 0xFF)
	Get minor version number from driver revision code.
#define	RTDM_DRIVER_PATCH_VER(ver)   ((ver) & 0xFF)
	Get patch version number from driver revision code.
Operation Handler Prototypes
typedef int(*	rtdm_open_handler_t )(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, int oflag)
	Named device open handler.
typedef int(*	rtdm_socket_handler_t )(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, int protocol)
	Socket creation handler for protocol devices.
typedef int(*	rtdm_close_handler_t )(struct rtdm_dev_context *context, rtdm_user_info_t *user_info)
	Close handler.
typedef int(*	rtdm_ioctl_handler_t )(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, int request, void *arg)
	IOCTL handler.
typedef ssize_t(*	rtdm_read_handler_t )(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, void *buf, size_t nbyte)
	Read handler.
typedef ssize_t(*	rtdm_write_handler_t )(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, const void *buf, size_t nbyte)
	Write handler.
typedef ssize_t(*	rtdm_recvmsg_handler_t )(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, struct msghdr *msg, int flags)
	Receive message handler.
typedef ssize_t(*	rtdm_sendmsg_handler_t )(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, const struct msghdr *msg, int flags)
	Transmit message handler.
Functions
int	rtdm_dev_register (struct rtdm_device *device)
	Register a RTDM device.
int	rtdm_dev_unregister (struct rtdm_device *device, unsigned int poll_delay)
	Unregisters a RTDM device.

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Typedef Documentation

typedef int(* rtdm_close_handler_t)(struct rtdm_dev_context *context, rtdm_user_info_t *user_info)

Close handler. Parameters: [in]  context  Context structure associated with opened device instance [in]  user_info  Opaque pointer to information about user mode caller, NULL if kernel mode call Returns: 0 on success, otherwise negative error code See also: close() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

typedef int(* rtdm_ioctl_handler_t)(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, int request, void *arg)

IOCTL handler. Parameters: [in]  context  Context structure associated with opened device instance [in]  user_info  Opaque pointer to information about user mode caller, NULL if kernel mode call [in]  request  Request number as passed by the user [in,out]  arg  Request argument as passed by the user Returns: Positiv value on success, otherwise negative error code See also: ioctl() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

typedef int(* rtdm_open_handler_t)(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, int oflag)

Named device open handler. Parameters: [in]  context  Context structure associated with opened device instance [in]  user_info  Opaque pointer to information about user mode caller, NULL if kernel mode call [in]  oflag  Open flags as passed by the user Returns: 0 on success, otherwise negative error code See also: open() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

typedef ssize_t(* rtdm_read_handler_t)(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, void *buf, size_t nbyte)

Read handler. Parameters: [in]  context  Context structure associated with opened device instance [in]  user_info  Opaque pointer to information about user mode caller, NULL if kernel mode call [out]  buf  Input buffer as passed by the user [in]  nbyte  Number of bytes the user requests to read Returns: On success, the number of bytes read, otherwise negative error code See also: read() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

typedef ssize_t(* rtdm_recvmsg_handler_t)(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, struct msghdr *msg, int flags)

Receive message handler. Parameters: [in]  context  Context structure associated with opened device instance [in]  user_info  Opaque pointer to information about user mode caller, NULL if kernel mode call [in,out]  msg  Message descriptor as passed by the user, automatically mirrored to safe kernel memory in case of user mode call [in]  flags  Message flags as passed by the user Returns: On success, the number of bytes received, otherwise negative error code See also: recvmsg() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

typedef ssize_t(* rtdm_sendmsg_handler_t)(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, const struct msghdr *msg, int flags)

Transmit message handler. Parameters: [in]  context  Context structure associated with opened device instance [in]  user_info  Opaque pointer to information about user mode caller, NULL if kernel mode call [in]  msg  Message descriptor as passed by the user, automatically mirrored to safe kernel memory in case of user mode call [in]  flags  Message flags as passed by the user Returns: On success, the number of bytes transmitted, otherwise negative error code See also: sendmsg() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

typedef int(* rtdm_socket_handler_t)(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, int protocol)

Socket creation handler for protocol devices. Parameters: [in]  context  Context structure associated with opened device instance [in]  user_info  Opaque pointer to information about user mode caller, NULL if kernel mode call [in]  protocol  Protocol number as passed by the user Returns: 0 on success, otherwise negative error code See also: socket() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

typedef ssize_t(* rtdm_write_handler_t)(struct rtdm_dev_context *context, rtdm_user_info_t *user_info, const void *buf, size_t nbyte)

Write handler. Parameters: [in]  context  Context structure associated with opened device instance [in]  user_info  Opaque pointer to information about user mode caller, NULL if kernel mode call [in]  buf  Output buffer as passed by the user [in]  nbyte  Number of bytes the user requests to write Returns: On success, the number of bytes written, otherwise negative error code See also: write() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

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Function Documentation

int rtdm_dev_register (  struct rtdm_device *  device  )

Register a RTDM device. Parameters: [in]  device  Pointer to structure describing the new device. Returns: 0 is returned upon success. Otherwise: -EINVAL is returned if the device structure contains invalid entries. Check kernel log in this case. -ENOMEM is returned if the context for an exclusive device cannot be allocated. -EEXIST is returned if the specified device name of protocol ID is already in use. -EAGAIN is returned if some /proc entry cannot be created. Environments: This service can be called from: Kernel module initialization/cleanup code Rescheduling: never.

int rtdm_dev_unregister (  struct rtdm_device *  device, unsigned int  poll_delay )

Unregisters a RTDM device. Parameters: [in]  device  Pointer to structure describing the device to be unregistered. [in]  poll_delay  Polling delay in milliseconds to check repeatedly for open instances of device, or 0 for non-blocking mode. Returns: 0 is returned upon success. Otherwise: -ENODEV is returned if the device was not registered. -EAGAIN is returned if the device is busy with open instances and 0 has been passed for poll_delay. Environments: This service can be called from: Kernel module initialization/cleanup code Rescheduling: never.

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