dio_tsk.c
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上传日期:2008-01-29
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文件大小:4k
- /*
- * Copyright 2003 by Texas Instruments Incorporated.
- * All rights reserved. Property of Texas Instruments Incorporated.
- * Restricted rights to use, duplicate or disclose this code are
- * granted through contract.
- *
- */
- /* "@(#) DDK 1.11.00.00 11-04-03 (ddk-b13)" */
- /*
- * ======== dio_tsk.c ========
- * SEM based functions of DIO.
- *
- */
- #include <std.h>
- #include <dev.h>
- #include <que.h>
- #include <sem.h>
- #include <sys.h>
- #include <iom.h>
- #include <dio.h>
- Int DIO_tskIdle(DEV_Handle device, Bool flush);
- Int DIO_tskIssue(DEV_Handle device);
- Bool DIO_tskReady(DEV_Handle device, SEM_Handle sem);
- Int DIO_tskReclaim(DEV_Handle device);
- Void DIO_tskCallback(Ptr devp, DEV_Frame *frame);
- /*
- * ======== DIO_tskCallback ========
- */
- Void DIO_tskCallback(Ptr devp, DEV_Frame *frame)
- {
- DEV_Handle device = (DEV_Handle)devp;
- DIO_Handle dio = (DIO_Handle)device->object;
- if (frame->cmd == IOM_READ || frame->cmd == IOM_WRITE) {
- QUE_put(device->fromdevice, frame);
- SEM_post(dio->context.sems.complete);
- /*
- * If semaphore was registered with DIO_ready(), dio->ready will
- * be non-NULL. In this case, SIO_select() is probably waiting for
- * this semaphore to be posted by the first ready device.
- */
- if (dio->context.sems.ready) {
- SEM_post(dio->context.sems.ready);
- }
- }
- else {
- SEM_post(dio->context.sems.complete);
- }
- }
- /*
- * ======== DIO_tskIdle ========
- * DIO_tskIdle() puts the device back to the state it was in just after
- * DIO_open() was called.
- */
- Int DIO_tskIdle(DEV_Handle device, Bool flush)
- {
- DIO_Handle dio = (DIO_Handle)device->object;
- Uns pendCount = 0;
- DEV_Frame localFrame;
- Int status;
- localFrame.status = IOM_PENDING;
- if (device->mode == DEV_INPUT || flush) {
- localFrame.cmd = IOM_ABORT;
- }
- else {
- localFrame.cmd = IOM_FLUSH;
- }
- status = dio->fxns->mdSubmitChan(dio->chanp, &localFrame);
- if (status == IOM_PENDING) {
- for (;;) {
- if (SEM_pend(dio->context.sems.complete, device->timeout)) {
- /*
- * Break out of the for loop when the local abort/flush
- * frame status shows that it is complete.
- */
- if (localFrame.status == IOM_COMPLETED) {
- break;
- }
- else {
- /* keep track of data frame completions */
- pendCount++;
- }
- }
- else {
- return (SYS_ETIMEOUT);
- }
- }
- /*
- * Update complete semaphore so it corresponds to number of frames
- * on the 'todevice' queue. 'for' loop above may have made the
- * complete sem count inconsistent.
- */
- while (pendCount--) {
- SEM_post(dio->context.sems.complete);
- }
- }
- return (SYS_OK);
- }
- /*
- * ======== DIO_tskIssue ========
- */
- Int DIO_tskIssue(DEV_Handle device)
- {
- DIO_Handle dio = (DIO_Handle)device->object;
- DEV_Frame *frame;
- Int status;
- frame = QUE_get(device->todevice);
- frame->cmd = (device->mode == DEV_INPUT) ? IOM_READ : IOM_WRITE;
- frame->status = IOM_PENDING;
- status = dio->fxns->mdSubmitChan(dio->chanp, frame);
- if (status < 0) {
- return (SYS_EBADIO);
- }
- else {
- if (status == IOM_COMPLETED) {
- QUE_put(device->fromdevice, frame);
- SEM_post(dio->context.sems.complete);
- }
-
- return (SYS_OK);
- }
- }
- /*
- * ======== DIO_tskReady ========
- */
- Bool DIO_tskReady(DEV_Handle device, SEM_Handle sem)
- {
- DIO_Handle dio = (DIO_Handle)device->object;
- dio->context.sems.ready = sem;
- return (!(QUE_empty(device->fromdevice)));
- }
- /*
- * ======== DIO_tskReclaim ========
- */
- Int DIO_tskReclaim(DEV_Handle device)
- {
- DIO_Handle dio = (DIO_Handle)device->object;
- /*
- * Wait here if there are no buffers on the device->fromdevice
- * queue.
- */
- if (SEM_pend(dio->context.sems.complete, device->timeout)) {
- return (SYS_OK);
- }
- else {
- return (SYS_ETIMEOUT);
- }
- }