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If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner] .TH ATTACH 9E "Jan 7, 2004" .SH NAME attach \- Attach a device to the system, or resume it .SH SYNOPSIS .nf #include #include \fBint prefix\fR\fBattach\fR(\fBdev_info_t *\fR\fIdip\fR, \fBddi_attach_cmd_t\fR \fIcmd\fR); .fi .SH INTERFACE LEVEL illumos DDI specific (illumos DDI) .SH PARAMETERS .ne 2 .na \fB\fIdip\fR\fR .ad .RS 7n A pointer to the device's \fBdev_info\fR structure. .RE .sp .ne 2 .na \fB\fIcmd\fR\fR .ad .RS 7n Attach type. Possible values are \fBDDI_ATTACH\fR and \fBDDI_RESUME\fR. Other values are reserved. The driver must return \fBDDI_FAILURE\fR if reserved values are passed to it. .RE .SH DESCRIPTION The \fBattach\fR(9E) function is the device-specific initialization entry point. This entry point is \fBrequired\fR and must be written. .SS "DDI_ATTACH" The \fBDDI_ATTACH\fR command must be provided in the \fBattach\fR(9E) entry point. \fBDDI_ATTACH\fR is used to initialize a given device instance. When \fBattach\fR(9E) is called with \fIcmd\fR set to \fBDDI_ATTACH\fR, all normal kernel services (such as \fBkmem_alloc\fR(9F)) are available for use by the driver. Device interrupts are not blocked when attaching a device to the system. .sp .LP The \fBattach\fR(9E) function is called once for each instance of the device on the system with \fIcmd\fR set to \fBDDI_ATTACH\fR. Until \fBattach\fR(9E) succeeds, the only driver entry point which may be called is \fBgetinfo\fR(9E). See the \fIWriting Device Drivers\fR for more information. The instance number may be obtained using \fBddi_get_instance\fR(9F). .sp .LP At attach time, all components of a power-manageable device are assumed to be at unknown levels. Before using the device, the driver needs to bring the required component(s) to a known power level. The \fBpm_raise_power\fR(9F) function can be used to set the power level of a component. This function must not be called before data structures referenced in \fBpower\fR(9E) have been initialized. .SS "DDI_RESUME" The \fBattach()\fR function may be called with \fIcmd\fR set to \fBDDI_RESUME\fR after \fBdetach\fR(9E) has been successfully called with \fIcmd\fR set to \fBDDI_SUSPEND\fR. .sp .LP When called with \fIcmd\fR set to \fBDDI_RESUME\fR, \fBattach()\fR must restore the hardware state of a device (power may have been removed from the device), allow pending requests to continue, and service new requests. In this case, the driver must not make any assumptions about the state of the hardware, but must restore the state of the device except for the power level of components. .sp .LP If the device driver uses the automatic device Power Management interfaces (driver exports the \fBpm-components\fR(9P) property), the Power Management framework sets its notion of the power level of each component of a device to \fBunknown\fR while processing a \fBDDI_RESUME\fR command. .sp .LP The driver can deal with components during \fBDDI_RESUME\fR in one of the following ways: .RS +4 .TP 1. If the driver can determine the power level of the component without having to power it up (for example, by calling \fBddi_peek\fR(9F) or some other device-specific method) then it should notify the power level to the framework by calling \fBpm_power_has_changed\fR(9F). .RE .RS +4 .TP 2. The driver must also set its own notion of the power level of the component to \fBunknown\fR. The system will consider the component idle or busy based on the most recent call to \fBpm_idle_component\fR(9F) or \fBpm_busy_component\fR(9F) for that component. If the component is idle for sufficient time, the framework will call into the driver's \fBpower\fR(9E) entry point to turn the component off. If the driver needs to access the device, then it must call \fBpm_raise_power\fR(9F) to bring the component up to the level needed for the device access to succeed. The driver must honor any request to set the power level of the component, since it cannot make any assumption about what power level the component has (or it should have called \fBpm_power_has_changed\fR(9F) as outlined above). As a special case of this, the driver may bring the component to a known state because it wants to perform an operation on the device as part of its \fBDDI_RESUME\fR processing (such as loading firmware so that it can detect hot-plug events). .RE .SH RETURN VALUES The \fBattach()\fR function returns: .sp .ne 2 .na \fB\fBDDI_SUCCESS\fR\fR .ad .RS 15n Successful completion .RE .sp .ne 2 .na \fB\fBDDI_FAILURE\fR\fR .ad .RS 15n Operation failed .RE .SH ATTRIBUTES See \fBattributes\fR(7) for descriptions of the following attributes: .sp .sp .TS box; c | c l | l . ATTRIBUTE TYPE ATTRIBUTE VALUE _ Interface Stability Committed .TE .SH SEE ALSO .BR cpr (4), .BR pm (4D), .BR detach (9E), .BR getinfo (9E), .BR identify (9E), .BR open (9E), .BR power (9E), .BR probe (9E), .BR ddi_add_intr (9F), .BR ddi_create_minor_node (9F), .BR ddi_get_instance (9F), .BR ddi_map_regs (9F), .BR kmem_alloc (9F), .BR pm_raise_power (9F), .BR pm (9P), .BR pm-components (9P) .sp .LP \fIWriting Device Drivers\fR