1/*
2 * Access to HP-HIL MLC through HP System Device Controller.
3 *
4 * Copyright (c) 2001 Brian S. Julin
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions, and the following disclaimer,
12 * without modification.
13 * 2. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * Alternatively, this software may be distributed under the terms of the
17 * GNU General Public License ("GPL").
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
23 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 *
29 * References:
30 * HP-HIL Technical Reference Manual. Hewlett Packard Product No. 45918A
31 * System Device Controller Microprocessor Firmware Theory of Operation
32 * for Part Number 1820-4784 Revision B. Dwg No. A-1820-4784-2
33 *
34 */
35
36#include <linux/hil_mlc.h>
37#include <linux/hp_sdc.h>
38#include <linux/errno.h>
39#include <linux/kernel.h>
40#include <linux/module.h>
41#include <linux/init.h>
42#include <linux/string.h>
43#include <linux/semaphore.h>
44
45#define PREFIX "HP SDC MLC: "
46
47static hil_mlc hp_sdc_mlc;
48
49MODULE_AUTHOR("Brian S. Julin <bri@calyx.com>");
50MODULE_DESCRIPTION("Glue for onboard HIL MLC in HP-PARISC machines");
51MODULE_LICENSE("Dual BSD/GPL");
52
53static struct hp_sdc_mlc_priv_s {
54 int emtestmode;
55 hp_sdc_transaction trans;
56 u8 tseq[16];
57 int got5x;
58} hp_sdc_mlc_priv;
59
60/************************* Interrupt context ******************************/
61static void hp_sdc_mlc_isr (int irq, void *dev_id,
62 uint8_t status, uint8_t data)
63{
64 int idx;
65 hil_mlc *mlc = &hp_sdc_mlc;
66
67 write_lock(&mlc->lock);
68 if (mlc->icount < 0) {
69 printk(KERN_WARNING PREFIX "HIL Overflow!\n");
70 up(sem: &mlc->isem);
71 goto out;
72 }
73 idx = 15 - mlc->icount;
74 if ((status & HP_SDC_STATUS_IRQMASK) == HP_SDC_STATUS_HILDATA) {
75 mlc->ipacket[idx] |= data | HIL_ERR_INT;
76 mlc->icount--;
77 if (hp_sdc_mlc_priv.got5x || !idx)
78 goto check;
79 if ((mlc->ipacket[idx - 1] & HIL_PKT_ADDR_MASK) !=
80 (mlc->ipacket[idx] & HIL_PKT_ADDR_MASK)) {
81 mlc->ipacket[idx] &= ~HIL_PKT_ADDR_MASK;
82 mlc->ipacket[idx] |= (mlc->ipacket[idx - 1]
83 & HIL_PKT_ADDR_MASK);
84 }
85 goto check;
86 }
87 /* We know status is 5X */
88 if (data & HP_SDC_HIL_ISERR)
89 goto err;
90 mlc->ipacket[idx] =
91 (data & HP_SDC_HIL_R1MASK) << HIL_PKT_ADDR_SHIFT;
92 hp_sdc_mlc_priv.got5x = 1;
93 goto out;
94
95 check:
96 hp_sdc_mlc_priv.got5x = 0;
97 if (mlc->imatch == 0)
98 goto done;
99 if ((mlc->imatch == (HIL_ERR_INT | HIL_PKT_CMD | HIL_CMD_POL))
100 && (mlc->ipacket[idx] == (mlc->imatch | idx)))
101 goto done;
102 if (mlc->ipacket[idx] == mlc->imatch)
103 goto done;
104 goto out;
105
106 err:
107 printk(KERN_DEBUG PREFIX "err code %x\n", data);
108
109 switch (data) {
110 case HP_SDC_HIL_RC_DONE:
111 printk(KERN_WARNING PREFIX "Bastard SDC reconfigured loop!\n");
112 break;
113
114 case HP_SDC_HIL_ERR:
115 mlc->ipacket[idx] |= HIL_ERR_INT | HIL_ERR_PERR |
116 HIL_ERR_FERR | HIL_ERR_FOF;
117 break;
118
119 case HP_SDC_HIL_TO:
120 mlc->ipacket[idx] |= HIL_ERR_INT | HIL_ERR_LERR;
121 break;
122
123 case HP_SDC_HIL_RC:
124 printk(KERN_WARNING PREFIX "Bastard SDC decided to reconfigure loop!\n");
125 break;
126
127 default:
128 printk(KERN_WARNING PREFIX "Unknown HIL Error status (%x)!\n", data);
129 break;
130 }
131
132 /* No more data will be coming due to an error. */
133 done:
134 tasklet_schedule(t: mlc->tasklet);
135 up(sem: &mlc->isem);
136 out:
137 write_unlock(&mlc->lock);
138}
139
140
141/******************** Tasklet or userspace context functions ****************/
142
143static int hp_sdc_mlc_in(hil_mlc *mlc, suseconds_t timeout)
144{
145 struct hp_sdc_mlc_priv_s *priv;
146 int rc = 2;
147
148 priv = mlc->priv;
149
150 /* Try to down the semaphore */
151 if (down_trylock(sem: &mlc->isem)) {
152 if (priv->emtestmode) {
153 mlc->ipacket[0] =
154 HIL_ERR_INT | (mlc->opacket &
155 (HIL_PKT_CMD |
156 HIL_PKT_ADDR_MASK |
157 HIL_PKT_DATA_MASK));
158 mlc->icount = 14;
159 /* printk(KERN_DEBUG PREFIX ">[%x]\n", mlc->ipacket[0]); */
160 goto wasup;
161 }
162 if (time_after(jiffies, mlc->instart + mlc->intimeout)) {
163 /* printk("!%i %i",
164 tv.tv_usec - mlc->instart.tv_usec,
165 mlc->intimeout);
166 */
167 rc = 1;
168 up(sem: &mlc->isem);
169 }
170 goto done;
171 }
172 wasup:
173 up(sem: &mlc->isem);
174 rc = 0;
175 done:
176 return rc;
177}
178
179static int hp_sdc_mlc_cts(hil_mlc *mlc)
180{
181 struct hp_sdc_mlc_priv_s *priv;
182
183 priv = mlc->priv;
184
185 /* Try to down the semaphores -- they should be up. */
186 BUG_ON(down_trylock(&mlc->isem));
187 BUG_ON(down_trylock(&mlc->osem));
188
189 up(sem: &mlc->isem);
190 up(sem: &mlc->osem);
191
192 if (down_trylock(sem: &mlc->csem)) {
193 if (priv->trans.act.semaphore != &mlc->csem)
194 goto poll;
195 else
196 goto busy;
197 }
198
199 if (!(priv->tseq[4] & HP_SDC_USE_LOOP))
200 goto done;
201
202 poll:
203 priv->trans.act.semaphore = &mlc->csem;
204 priv->trans.actidx = 0;
205 priv->trans.idx = 1;
206 priv->trans.endidx = 5;
207 priv->tseq[0] =
208 HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN | HP_SDC_ACT_SEMAPHORE;
209 priv->tseq[1] = HP_SDC_CMD_READ_USE;
210 priv->tseq[2] = 1;
211 priv->tseq[3] = 0;
212 priv->tseq[4] = 0;
213 return __hp_sdc_enqueue_transaction(this: &priv->trans);
214 busy:
215 return 1;
216 done:
217 priv->trans.act.semaphore = &mlc->osem;
218 up(sem: &mlc->csem);
219 return 0;
220}
221
222static int hp_sdc_mlc_out(hil_mlc *mlc)
223{
224 struct hp_sdc_mlc_priv_s *priv;
225
226 priv = mlc->priv;
227
228 /* Try to down the semaphore -- it should be up. */
229 BUG_ON(down_trylock(&mlc->osem));
230
231 if (mlc->opacket & HIL_DO_ALTER_CTRL)
232 goto do_control;
233
234 do_data:
235 if (priv->emtestmode) {
236 up(sem: &mlc->osem);
237 return 0;
238 }
239 /* Shouldn't be sending commands when loop may be busy */
240 BUG_ON(down_trylock(&mlc->csem));
241 up(sem: &mlc->csem);
242
243 priv->trans.actidx = 0;
244 priv->trans.idx = 1;
245 priv->trans.act.semaphore = &mlc->osem;
246 priv->trans.endidx = 6;
247 priv->tseq[0] =
248 HP_SDC_ACT_DATAREG | HP_SDC_ACT_POSTCMD | HP_SDC_ACT_SEMAPHORE;
249 priv->tseq[1] = 0x7;
250 priv->tseq[2] =
251 (mlc->opacket &
252 (HIL_PKT_ADDR_MASK | HIL_PKT_CMD))
253 >> HIL_PKT_ADDR_SHIFT;
254 priv->tseq[3] =
255 (mlc->opacket & HIL_PKT_DATA_MASK)
256 >> HIL_PKT_DATA_SHIFT;
257 priv->tseq[4] = 0; /* No timeout */
258 if (priv->tseq[3] == HIL_CMD_DHR)
259 priv->tseq[4] = 1;
260 priv->tseq[5] = HP_SDC_CMD_DO_HIL;
261 goto enqueue;
262
263 do_control:
264 priv->emtestmode = mlc->opacket & HIL_CTRL_TEST;
265
266 /* we cannot emulate this, it should not be used. */
267 BUG_ON((mlc->opacket & (HIL_CTRL_APE | HIL_CTRL_IPF)) == HIL_CTRL_APE);
268
269 if ((mlc->opacket & HIL_CTRL_ONLY) == HIL_CTRL_ONLY)
270 goto control_only;
271
272 /* Should not send command/data after engaging APE */
273 BUG_ON(mlc->opacket & HIL_CTRL_APE);
274
275 /* Disengaging APE this way would not be valid either since
276 * the loop must be allowed to idle.
277 *
278 * So, it works out that we really never actually send control
279 * and data when using SDC, we just send the data.
280 */
281 goto do_data;
282
283 control_only:
284 priv->trans.actidx = 0;
285 priv->trans.idx = 1;
286 priv->trans.act.semaphore = &mlc->osem;
287 priv->trans.endidx = 4;
288 priv->tseq[0] =
289 HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT | HP_SDC_ACT_SEMAPHORE;
290 priv->tseq[1] = HP_SDC_CMD_SET_LPC;
291 priv->tseq[2] = 1;
292 /* priv->tseq[3] = (mlc->ddc + 1) | HP_SDC_LPS_ACSUCC; */
293 priv->tseq[3] = 0;
294 if (mlc->opacket & HIL_CTRL_APE) {
295 priv->tseq[3] |= HP_SDC_LPC_APE_IPF;
296 BUG_ON(down_trylock(&mlc->csem));
297 }
298 enqueue:
299 return hp_sdc_enqueue_transaction(this: &priv->trans);
300}
301
302static int __init hp_sdc_mlc_init(void)
303{
304 hil_mlc *mlc = &hp_sdc_mlc;
305 int err;
306
307#ifdef __mc68000__
308 if (!MACH_IS_HP300)
309 return -ENODEV;
310#endif
311
312 printk(KERN_INFO PREFIX "Registering the System Domain Controller's HIL MLC.\n");
313
314 hp_sdc_mlc_priv.emtestmode = 0;
315 hp_sdc_mlc_priv.trans.seq = hp_sdc_mlc_priv.tseq;
316 hp_sdc_mlc_priv.trans.act.semaphore = &mlc->osem;
317 hp_sdc_mlc_priv.got5x = 0;
318
319 mlc->cts = &hp_sdc_mlc_cts;
320 mlc->in = &hp_sdc_mlc_in;
321 mlc->out = &hp_sdc_mlc_out;
322 mlc->priv = &hp_sdc_mlc_priv;
323
324 err = hil_mlc_register(mlc);
325 if (err) {
326 printk(KERN_WARNING PREFIX "Failed to register MLC structure with hil_mlc\n");
327 return err;
328 }
329
330 if (hp_sdc_request_hil_irq(callback: &hp_sdc_mlc_isr)) {
331 printk(KERN_WARNING PREFIX "Request for raw HIL ISR hook denied\n");
332 if (hil_mlc_unregister(mlc))
333 printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n"
334 "This is bad. Could cause an oops.\n");
335 return -EBUSY;
336 }
337
338 return 0;
339}
340
341static void __exit hp_sdc_mlc_exit(void)
342{
343 hil_mlc *mlc = &hp_sdc_mlc;
344
345 if (hp_sdc_release_hil_irq(callback: &hp_sdc_mlc_isr))
346 printk(KERN_ERR PREFIX "Failed to release the raw HIL ISR hook.\n"
347 "This is bad. Could cause an oops.\n");
348
349 if (hil_mlc_unregister(mlc))
350 printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n"
351 "This is bad. Could cause an oops.\n");
352}
353
354module_init(hp_sdc_mlc_init);
355module_exit(hp_sdc_mlc_exit);
356

source code of linux/drivers/input/serio/hp_sdc_mlc.c