ide-atapi.c revision 646c0cb6c430f8d3ad3769dd1518fe664ff0ce27 
1/*
2 * ATAPI support.
3 */
4
5#include <linux/kernel.h>
6#include <linux/delay.h>
7#include <linux/ide.h>
8#include <scsi/scsi.h>
9
10#ifdef DEBUG
11#define debug_log(fmt, args...) \
12	printk(KERN_INFO "ide: " fmt, ## args)
13#else
14#define debug_log(fmt, args...) do {} while (0)
15#endif
16
17/* TODO: unify the code thus making some arguments go away */
18ide_startstop_t ide_pc_intr(ide_drive_t *drive, struct ide_atapi_pc *pc,
19	ide_handler_t *handler, unsigned int timeout, ide_expiry_t *expiry,
20	void (*update_buffers)(ide_drive_t *, struct ide_atapi_pc *),
21	void (*retry_pc)(ide_drive_t *), void (*dsc_handle)(ide_drive_t *),
22	void (*io_buffers)(ide_drive_t *, struct ide_atapi_pc *, unsigned, int))
23{
24	ide_hwif_t *hwif = drive->hwif;
25	xfer_func_t *xferfunc;
26	unsigned int temp;
27	u16 bcount;
28	u8 stat, ireason, scsi = drive->scsi;
29
30	debug_log("Enter %s - interrupt handler\n", __func__);
31
32	if (pc->flags & PC_FLAG_TIMEDOUT) {
33		pc->callback(drive);
34		return ide_stopped;
35	}
36
37	/* Clear the interrupt */
38	stat = ide_read_status(drive);
39
40	if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
41		if (hwif->dma_ops->dma_end(drive) ||
42		    (drive->media == ide_tape && !scsi && (stat & ERR_STAT))) {
43			if (drive->media == ide_floppy && !scsi)
44				printk(KERN_ERR "%s: DMA %s error\n",
45					drive->name, rq_data_dir(pc->rq)
46						     ? "write" : "read");
47			pc->flags |= PC_FLAG_DMA_ERROR;
48		} else {
49			pc->xferred = pc->req_xfer;
50			if (update_buffers)
51				update_buffers(drive, pc);
52		}
53		debug_log("%s: DMA finished\n", drive->name);
54	}
55
56	/* No more interrupts */
57	if ((stat & DRQ_STAT) == 0) {
58		debug_log("Packet command completed, %d bytes transferred\n",
59			  pc->xferred);
60
61		pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
62
63		local_irq_enable_in_hardirq();
64
65		if (drive->media == ide_tape && !scsi &&
66		    (stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE)
67			stat &= ~ERR_STAT;
68		if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) {
69			/* Error detected */
70			debug_log("%s: I/O error\n", drive->name);
71
72			if (drive->media != ide_tape || scsi) {
73				pc->rq->errors++;
74				if (scsi)
75					goto cmd_finished;
76			}
77
78			if (pc->c[0] == REQUEST_SENSE) {
79				printk(KERN_ERR "%s: I/O error in request sense"
80						" command\n", drive->name);
81				return ide_do_reset(drive);
82			}
83
84			debug_log("[cmd %x]: check condition\n", pc->c[0]);
85
86			/* Retry operation */
87			retry_pc(drive);
88			/* queued, but not started */
89			return ide_stopped;
90		}
91cmd_finished:
92		pc->error = 0;
93		if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) &&
94		    (stat & SEEK_STAT) == 0) {
95			dsc_handle(drive);
96			return ide_stopped;
97		}
98		/* Command finished - Call the callback function */
99		pc->callback(drive);
100		return ide_stopped;
101	}
102
103	if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
104		pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
105		printk(KERN_ERR "%s: The device wants to issue more interrupts "
106				"in DMA mode\n", drive->name);
107		ide_dma_off(drive);
108		return ide_do_reset(drive);
109	}
110	/* Get the number of bytes to transfer on this interrupt. */
111	bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) |
112		  hwif->INB(hwif->io_ports.lbam_addr);
113
114	ireason = hwif->INB(hwif->io_ports.nsect_addr);
115
116	if (ireason & CD) {
117		printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
118		return ide_do_reset(drive);
119	}
120	if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) {
121		/* Hopefully, we will never get here */
122		printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
123				"to %s!\n", drive->name,
124				(ireason & IO) ? "Write" : "Read",
125				(ireason & IO) ? "Read" : "Write");
126		return ide_do_reset(drive);
127	}
128	if (!(pc->flags & PC_FLAG_WRITING)) {
129		/* Reading - Check that we have enough space */
130		temp = pc->xferred + bcount;
131		if (temp > pc->req_xfer) {
132			if (temp > pc->buf_size) {
133				printk(KERN_ERR "%s: The device wants to send "
134						"us more data than expected - "
135						"discarding data\n",
136						drive->name);
137				if (scsi)
138					temp = pc->buf_size - pc->xferred;
139				else
140					temp = 0;
141				if (temp) {
142					if (pc->sg)
143						io_buffers(drive, pc, temp, 0);
144					else
145						hwif->input_data(drive, NULL,
146							pc->cur_pos, temp);
147					printk(KERN_ERR "%s: transferred %d of "
148							"%d bytes\n",
149							drive->name,
150							temp, bcount);
151				}
152				pc->xferred += temp;
153				pc->cur_pos += temp;
154				ide_pad_transfer(drive, 0, bcount - temp);
155				ide_set_handler(drive, handler, timeout,
156						expiry);
157				return ide_started;
158			}
159			debug_log("The device wants to send us more data than "
160				  "expected - allowing transfer\n");
161		}
162		xferfunc = hwif->input_data;
163	} else
164		xferfunc = hwif->output_data;
165
166	if ((drive->media == ide_floppy && !scsi && !pc->buf) ||
167	    (drive->media == ide_tape && !scsi && pc->bh) ||
168	    (scsi && pc->sg))
169		io_buffers(drive, pc, bcount, !!(pc->flags & PC_FLAG_WRITING));
170	else
171		xferfunc(drive, NULL, pc->cur_pos, bcount);
172
173	/* Update the current position */
174	pc->xferred += bcount;
175	pc->cur_pos += bcount;
176
177	debug_log("[cmd %x] transferred %d bytes on that intr.\n",
178		  pc->c[0], bcount);
179
180	/* And set the interrupt handler again */
181	ide_set_handler(drive, handler, timeout, expiry);
182	return ide_started;
183}
184EXPORT_SYMBOL_GPL(ide_pc_intr);
185
186static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
187{
188	ide_hwif_t *hwif = drive->hwif;
189	int retries = 100;
190
191	while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) {
192		printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
193				"a packet command, retrying\n", drive->name);
194		udelay(100);
195		ireason = hwif->INB(hwif->io_ports.nsect_addr);
196		if (retries == 0) {
197			printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
198					"a packet command, ignoring\n",
199					drive->name);
200			ireason |= CD;
201			ireason &= ~IO;
202		}
203	}
204
205	return ireason;
206}
207
208ide_startstop_t ide_transfer_pc(ide_drive_t *drive, struct ide_atapi_pc *pc,
209				ide_handler_t *handler, unsigned int timeout,
210				ide_expiry_t *expiry)
211{
212	ide_hwif_t *hwif = drive->hwif;
213	ide_startstop_t startstop;
214	u8 ireason;
215
216	if (ide_wait_stat(&startstop, drive, DRQ_STAT, BUSY_STAT, WAIT_READY)) {
217		printk(KERN_ERR "%s: Strange, packet command initiated yet "
218				"DRQ isn't asserted\n", drive->name);
219		return startstop;
220	}
221
222	ireason = hwif->INB(hwif->io_ports.nsect_addr);
223	if (drive->media == ide_tape && !drive->scsi)
224		ireason = ide_wait_ireason(drive, ireason);
225
226	if ((ireason & CD) == 0 || (ireason & IO)) {
227		printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
228				"a packet command\n", drive->name);
229		return ide_do_reset(drive);
230	}
231
232	/* Set the interrupt routine */
233	ide_set_handler(drive, handler, timeout, expiry);
234
235	/* Begin DMA, if necessary */
236	if (pc->flags & PC_FLAG_DMA_OK) {
237		pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
238		hwif->dma_ops->dma_start(drive);
239	}
240
241	/* Send the actual packet */
242	if ((pc->flags & PC_FLAG_ZIP_DRIVE) == 0)
243		hwif->output_data(drive, NULL, pc->c, 12);
244
245	return ide_started;
246}
247EXPORT_SYMBOL_GPL(ide_transfer_pc);
248
249ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_atapi_pc *pc,
250			     ide_handler_t *handler, unsigned int timeout,
251			     ide_expiry_t *expiry)
252{
253	ide_hwif_t *hwif = drive->hwif;
254	u16 bcount;
255	u8 dma = 0;
256
257	/* We haven't transferred any data yet */
258	pc->xferred = 0;
259	pc->cur_pos = pc->buf;
260
261	/* Request to transfer the entire buffer at once */
262	if (drive->media == ide_tape && !drive->scsi)
263		bcount = pc->req_xfer;
264	else
265		bcount = min(pc->req_xfer, 63 * 1024);
266
267	if (pc->flags & PC_FLAG_DMA_ERROR) {
268		pc->flags &= ~PC_FLAG_DMA_ERROR;
269		ide_dma_off(drive);
270	}
271
272	if ((pc->flags & PC_FLAG_DMA_OK) && drive->using_dma) {
273		if (drive->scsi)
274			hwif->sg_mapped = 1;
275		dma = !hwif->dma_ops->dma_setup(drive);
276		if (drive->scsi)
277			hwif->sg_mapped = 0;
278	}
279
280	if (!dma)
281		pc->flags &= ~PC_FLAG_DMA_OK;
282
283	ide_pktcmd_tf_load(drive, drive->scsi ? 0 : IDE_TFLAG_OUT_DEVICE,
284			   bcount, dma);
285
286	/* Issue the packet command */
287	if (pc->flags & PC_FLAG_DRQ_INTERRUPT) {
288		ide_execute_command(drive, WIN_PACKETCMD, handler,
289				    timeout, NULL);
290		return ide_started;
291	} else {
292		ide_execute_pkt_cmd(drive);
293		return (*handler)(drive);
294	}
295}
296EXPORT_SYMBOL_GPL(ide_issue_pc);
297