4 * Copyright (C) 2005 Mike Isely <isely@pobox.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #include <linux/i2c.h>
22 #include "pvrusb2-i2c-core.h"
23 #include "pvrusb2-hdw-internal.h"
24 #include "pvrusb2-debug.h"
25 #include "pvrusb2-fx2-cmd.h"
28 #define trace_i2c(...) pvr2_trace(PVR2_TRACE_I2C,__VA_ARGS__)
32 This module attempts to implement a compliant I2C adapter for the pvrusb2
37 static unsigned int i2c_scan;
38 module_param(i2c_scan, int, S_IRUGO|S_IWUSR);
39 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
41 static int ir_mode[PVR_NUM] = { [0 ... PVR_NUM-1] = 1 };
42 module_param_array(ir_mode, int, NULL, 0444);
43 MODULE_PARM_DESC(ir_mode,"specify: 0=disable IR reception, 1=normal IR");
45 static int pvr2_disable_ir_video;
46 module_param_named(disable_autoload_ir_video, pvr2_disable_ir_video,
47 int, S_IRUGO|S_IWUSR);
48 MODULE_PARM_DESC(disable_autoload_ir_video,
49 "1=do not try to autoload ir_video IR receiver");
51 /* Mapping of IR schemes to known I2C addresses - if any */
52 static const unsigned char ir_video_addresses[] = {
53 [PVR2_IR_SCHEME_29XXX] = 0x18,
54 [PVR2_IR_SCHEME_24XXX] = 0x18,
57 static int pvr2_i2c_write(struct pvr2_hdw *hdw, /* Context */
58 u8 i2c_addr, /* I2C address we're talking to */
59 u8 *data, /* Data to write */
60 u16 length) /* Size of data to write */
62 /* Return value - default 0 means success */
66 if (!data) length = 0;
67 if (length > (sizeof(hdw->cmd_buffer) - 3)) {
68 pvr2_trace(PVR2_TRACE_ERROR_LEGS,
69 "Killing an I2C write to %u that is too large"
70 " (desired=%u limit=%u)",
72 length,(unsigned int)(sizeof(hdw->cmd_buffer) - 3));
76 LOCK_TAKE(hdw->ctl_lock);
78 /* Clear the command buffer (likely to be paranoia) */
79 memset(hdw->cmd_buffer, 0, sizeof(hdw->cmd_buffer));
81 /* Set up command buffer for an I2C write */
82 hdw->cmd_buffer[0] = FX2CMD_I2C_WRITE; /* write prefix */
83 hdw->cmd_buffer[1] = i2c_addr; /* i2c addr of chip */
84 hdw->cmd_buffer[2] = length; /* length of what follows */
85 if (length) memcpy(hdw->cmd_buffer + 3, data, length);
87 /* Do the operation */
88 ret = pvr2_send_request(hdw,
94 if (hdw->cmd_buffer[0] != 8) {
96 if (hdw->cmd_buffer[0] != 7) {
97 trace_i2c("unexpected status"
98 " from i2_write[%d]: %d",
99 i2c_addr,hdw->cmd_buffer[0]);
104 LOCK_GIVE(hdw->ctl_lock);
109 static int pvr2_i2c_read(struct pvr2_hdw *hdw, /* Context */
110 u8 i2c_addr, /* I2C address we're talking to */
111 u8 *data, /* Data to write */
112 u16 dlen, /* Size of data to write */
113 u8 *res, /* Where to put data we read */
114 u16 rlen) /* Amount of data to read */
116 /* Return value - default 0 means success */
121 if (dlen > (sizeof(hdw->cmd_buffer) - 4)) {
122 pvr2_trace(PVR2_TRACE_ERROR_LEGS,
123 "Killing an I2C read to %u that has wlen too large"
124 " (desired=%u limit=%u)",
126 dlen,(unsigned int)(sizeof(hdw->cmd_buffer) - 4));
129 if (res && (rlen > (sizeof(hdw->cmd_buffer) - 1))) {
130 pvr2_trace(PVR2_TRACE_ERROR_LEGS,
131 "Killing an I2C read to %u that has rlen too large"
132 " (desired=%u limit=%u)",
134 rlen,(unsigned int)(sizeof(hdw->cmd_buffer) - 1));
138 LOCK_TAKE(hdw->ctl_lock);
140 /* Clear the command buffer (likely to be paranoia) */
141 memset(hdw->cmd_buffer, 0, sizeof(hdw->cmd_buffer));
143 /* Set up command buffer for an I2C write followed by a read */
144 hdw->cmd_buffer[0] = FX2CMD_I2C_READ; /* read prefix */
145 hdw->cmd_buffer[1] = dlen; /* arg length */
146 hdw->cmd_buffer[2] = rlen; /* answer length. Device will send one
147 more byte (status). */
148 hdw->cmd_buffer[3] = i2c_addr; /* i2c addr of chip */
149 if (dlen) memcpy(hdw->cmd_buffer + 4, data, dlen);
151 /* Do the operation */
152 ret = pvr2_send_request(hdw,
158 if (hdw->cmd_buffer[0] != 8) {
160 if (hdw->cmd_buffer[0] != 7) {
161 trace_i2c("unexpected status"
162 " from i2_read[%d]: %d",
163 i2c_addr,hdw->cmd_buffer[0]);
168 /* Copy back the result */
171 /* Error, just blank out the return buffer */
172 memset(res, 0, rlen);
174 memcpy(res, hdw->cmd_buffer + 1, rlen);
178 LOCK_GIVE(hdw->ctl_lock);
183 /* This is the common low level entry point for doing I2C operations to the
185 static int pvr2_i2c_basic_op(struct pvr2_hdw *hdw,
192 if (!rdata) rlen = 0;
193 if (!wdata) wlen = 0;
195 return pvr2_i2c_read(hdw,i2c_addr,wdata,wlen,rdata,rlen);
197 return pvr2_i2c_write(hdw,i2c_addr,wdata,wlen);
202 /* This is a special entry point for cases of I2C transaction attempts to
203 the IR receiver. The implementation here simulates the IR receiver by
204 issuing a command to the FX2 firmware and using that response to return
205 what the real I2C receiver would have returned. We use this for 24xxx
206 devices, where the IR receiver chip has been removed and replaced with
207 FX2 related logic. */
208 static int i2c_24xxx_ir(struct pvr2_hdw *hdw,
209 u8 i2c_addr,u8 *wdata,u16 wlen,u8 *rdata,u16 rlen)
214 if (!(rlen || wlen)) {
215 /* This is a probe attempt. Just let it succeed. */
219 /* We don't understand this kind of transaction */
220 if ((wlen != 0) || (rlen == 0)) return -EIO;
223 /* Mike Isely <isely@pobox.com> Appears to be a probe
224 attempt from lirc. Just fill in zeroes and return. If
225 we try instead to do the full transaction here, then bad
226 things seem to happen within the lirc driver module
227 (version 0.8.0-7 sources from Debian, when run under
228 vanilla 2.6.17.6 kernel) - and I don't have the patience
230 if (rlen > 0) rdata[0] = 0;
231 if (rlen > 1) rdata[1] = 0;
235 /* Issue a command to the FX2 to read the IR receiver. */
236 LOCK_TAKE(hdw->ctl_lock); do {
237 hdw->cmd_buffer[0] = FX2CMD_GET_IR_CODE;
238 stat = pvr2_send_request(hdw,
241 dat[0] = hdw->cmd_buffer[0];
242 dat[1] = hdw->cmd_buffer[1];
243 dat[2] = hdw->cmd_buffer[2];
244 dat[3] = hdw->cmd_buffer[3];
245 } while (0); LOCK_GIVE(hdw->ctl_lock);
247 /* Give up if that operation failed. */
248 if (stat != 0) return stat;
250 /* Mangle the results into something that looks like the real IR
254 /* No code received. */
259 /* Mash the FX2 firmware-provided IR code into something
260 that the normal i2c chip-level driver expects. */
267 rdata[0] = (val >> 8) & 0xffu;
268 rdata[1] = val & 0xffu;
274 /* This is a special entry point that is entered if an I2C operation is
275 attempted to a wm8775 chip on model 24xxx hardware. Autodetect of this
276 part doesn't work, but we know it is really there. So let's look for
277 the autodetect attempt and just return success if we see that. */
278 static int i2c_hack_wm8775(struct pvr2_hdw *hdw,
279 u8 i2c_addr,u8 *wdata,u16 wlen,u8 *rdata,u16 rlen)
281 if (!(rlen || wlen)) {
282 // This is a probe attempt. Just let it succeed.
285 return pvr2_i2c_basic_op(hdw,i2c_addr,wdata,wlen,rdata,rlen);
288 /* This is an entry point designed to always fail any attempt to perform a
289 transfer. We use this to cause certain I2C addresses to not be
291 static int i2c_black_hole(struct pvr2_hdw *hdw,
292 u8 i2c_addr,u8 *wdata,u16 wlen,u8 *rdata,u16 rlen)
297 /* This is a special entry point that is entered if an I2C operation is
298 attempted to a cx25840 chip on model 24xxx hardware. This chip can
299 sometimes wedge itself. Worse still, when this happens msp3400 can
300 falsely detect this part and then the system gets hosed up after msp3400
301 gets confused and dies. What we want to do here is try to keep msp3400
302 away and also try to notice if the chip is wedged and send a warning to
304 static int i2c_hack_cx25840(struct pvr2_hdw *hdw,
305 u8 i2c_addr,u8 *wdata,u16 wlen,u8 *rdata,u16 rlen)
308 unsigned int subaddr;
310 int state = hdw->i2c_cx25840_hack_state;
312 if (!(rlen || wlen)) {
313 // Probe attempt - always just succeed and don't bother the
314 // hardware (this helps to make the state machine further
315 // down somewhat easier).
320 return pvr2_i2c_basic_op(hdw,i2c_addr,wdata,wlen,rdata,rlen);
323 /* We're looking for the exact pattern where the revision register
324 is being read. The cx25840 module will always look at the
325 revision register first. Any other pattern of access therefore
326 has to be a probe attempt from somebody else so we'll reject it.
327 Normally we could just let each client just probe the part
328 anyway, but when the cx25840 is wedged, msp3400 will get a false
329 positive and that just screws things up... */
333 case 1: subaddr = 0x0100; break;
334 case 2: subaddr = 0x0101; break;
337 } else if (wlen == 2) {
338 subaddr = (wdata[0] << 8) | wdata[1];
340 case 0x0100: state = 1; break;
341 case 0x0101: state = 2; break;
347 if (!rlen) goto success;
349 if (rlen != 1) goto fail;
351 /* If we get to here then we have a legitimate read for one of the
352 two revision bytes, so pass it through. */
353 wbuf[0] = subaddr >> 8;
355 ret = pvr2_i2c_basic_op(hdw,i2c_addr,wbuf,2,rdata,rlen);
357 if ((ret != 0) || (*rdata == 0x04) || (*rdata == 0x0a)) {
358 pvr2_trace(PVR2_TRACE_ERROR_LEGS,
359 "WARNING: Detected a wedged cx25840 chip;"
360 " the device will not work.");
361 pvr2_trace(PVR2_TRACE_ERROR_LEGS,
362 "WARNING: Try power cycling the pvrusb2 device.");
363 pvr2_trace(PVR2_TRACE_ERROR_LEGS,
364 "WARNING: Disabling further access to the device"
365 " to prevent other foul-ups.");
366 // This blocks all further communication with the part.
367 hdw->i2c_func[0x44] = NULL;
368 pvr2_hdw_render_useless(hdw);
373 pvr2_trace(PVR2_TRACE_CHIPS,"cx25840 appears to be OK.");
377 hdw->i2c_cx25840_hack_state = state;
381 hdw->i2c_cx25840_hack_state = state;
385 /* This is a very, very limited I2C adapter implementation. We can only
386 support what we actually know will work on the device... */
387 static int pvr2_i2c_xfer(struct i2c_adapter *i2c_adap,
388 struct i2c_msg msgs[],
392 pvr2_i2c_func funcp = NULL;
393 struct pvr2_hdw *hdw = (struct pvr2_hdw *)(i2c_adap->algo_data);
399 if (msgs[0].addr < PVR2_I2C_FUNC_CNT) {
400 funcp = hdw->i2c_func[msgs[0].addr];
408 if (msgs[0].flags & I2C_M_RD) {
412 /* Length == 0 read. This is a probe. */
413 if (funcp(hdw,msgs[0].addr,NULL,0,NULL,0)) {
420 /* If the read is short enough we'll do the whole
421 thing atomically. Otherwise we have no choice
422 but to break apart the reads. */
427 if (bcnt > sizeof(hdw->cmd_buffer)-1) {
428 bcnt = sizeof(hdw->cmd_buffer)-1;
430 if (funcp(hdw,msgs[0].addr,NULL,0,
431 msgs[0].buf+offs,bcnt)) {
443 if (funcp(hdw,msgs[0].addr,
444 msgs[0].buf,msgs[0].len,NULL,0)) {
449 } else if (num == 2) {
450 if (msgs[0].addr != msgs[1].addr) {
451 trace_i2c("i2c refusing 2 phase transfer with"
452 " conflicting target addresses");
456 if ((!((msgs[0].flags & I2C_M_RD))) &&
457 (msgs[1].flags & I2C_M_RD)) {
458 u16 tcnt,bcnt,wcnt,offs;
459 /* Write followed by atomic read. If the read
460 portion is short enough we'll do the whole thing
461 atomically. Otherwise we have no choice but to
462 break apart the reads. */
466 while (tcnt || wcnt) {
468 if (bcnt > sizeof(hdw->cmd_buffer)-1) {
469 bcnt = sizeof(hdw->cmd_buffer)-1;
471 if (funcp(hdw,msgs[0].addr,
473 msgs[1].buf+offs,bcnt)) {
484 trace_i2c("i2c refusing complex transfer"
485 " read0=%d read1=%d",
486 (msgs[0].flags & I2C_M_RD),
487 (msgs[1].flags & I2C_M_RD));
490 trace_i2c("i2c refusing %d phase transfer",num);
494 if (pvrusb2_debug & PVR2_TRACE_I2C_TRAF) {
495 unsigned int idx,offs,cnt;
496 for (idx = 0; idx < num; idx++) {
499 "pvrusb2 i2c xfer %u/%u:"
500 " addr=0x%x len=%d %s",
504 (msgs[idx].flags & I2C_M_RD ?
506 if ((ret > 0) || !(msgs[idx].flags & I2C_M_RD)) {
507 if (cnt > 8) cnt = 8;
509 for (offs = 0; offs < (cnt>8?8:cnt); offs++) {
510 if (offs) printk(" ");
511 printk("%02x",msgs[idx].buf[offs]);
513 if (offs < cnt) printk(" ...");
517 printk(" result=%d",ret);
523 "pvrusb2 i2c xfer null transfer result=%d\n",
530 static u32 pvr2_i2c_functionality(struct i2c_adapter *adap)
532 return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
535 static struct i2c_algorithm pvr2_i2c_algo_template = {
536 .master_xfer = pvr2_i2c_xfer,
537 .functionality = pvr2_i2c_functionality,
540 static struct i2c_adapter pvr2_i2c_adap_template = {
541 .owner = THIS_MODULE,
543 .id = I2C_HW_B_BT848,
547 /* Return true if device exists at given address */
548 static int do_i2c_probe(struct pvr2_hdw *hdw, int addr)
550 struct i2c_msg msg[1];
553 msg[0].flags = I2C_M_RD;
557 rc = i2c_transfer(&hdw->i2c_adap, msg, ARRAY_SIZE(msg));
561 static void do_i2c_scan(struct pvr2_hdw *hdw)
564 printk(KERN_INFO "%s: i2c scan beginning\n", hdw->name);
565 for (i = 0; i < 128; i++) {
566 if (do_i2c_probe(hdw, i)) {
567 printk(KERN_INFO "%s: i2c scan: found device @ 0x%x\n",
571 printk(KERN_INFO "%s: i2c scan done.\n", hdw->name);
574 static void pvr2_i2c_register_ir(struct pvr2_hdw *hdw)
576 struct i2c_board_info info;
577 unsigned char addr = 0;
578 if (pvr2_disable_ir_video) {
579 pvr2_trace(PVR2_TRACE_INFO,
580 "Automatic binding of ir_video has been disabled.");
583 if (hdw->ir_scheme_active < ARRAY_SIZE(ir_video_addresses)) {
584 addr = ir_video_addresses[hdw->ir_scheme_active];
587 /* The device either doesn't support I2C-based IR or we
588 don't know (yet) how to operate IR on the device. */
591 pvr2_trace(PVR2_TRACE_INFO,
592 "Binding ir_video to i2c address 0x%02x.", addr);
593 memset(&info, 0, sizeof(struct i2c_board_info));
594 strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
596 i2c_new_device(&hdw->i2c_adap, &info);
599 void pvr2_i2c_core_init(struct pvr2_hdw *hdw)
603 /* The default action for all possible I2C addresses is just to do
604 the transfer normally. */
605 for (idx = 0; idx < PVR2_I2C_FUNC_CNT; idx++) {
606 hdw->i2c_func[idx] = pvr2_i2c_basic_op;
609 /* However, deal with various special cases for 24xxx hardware. */
610 if (ir_mode[hdw->unit_number] == 0) {
611 printk(KERN_INFO "%s: IR disabled\n",hdw->name);
612 hdw->i2c_func[0x18] = i2c_black_hole;
613 } else if (ir_mode[hdw->unit_number] == 1) {
614 if (hdw->ir_scheme_active == PVR2_IR_SCHEME_24XXX) {
615 /* Set up translation so that our IR looks like a
617 hdw->i2c_func[0x18] = i2c_24xxx_ir;
620 if (hdw->hdw_desc->flag_has_cx25840) {
621 hdw->i2c_func[0x44] = i2c_hack_cx25840;
623 if (hdw->hdw_desc->flag_has_wm8775) {
624 hdw->i2c_func[0x1b] = i2c_hack_wm8775;
627 // Configure the adapter and set up everything else related to it.
628 memcpy(&hdw->i2c_adap,&pvr2_i2c_adap_template,sizeof(hdw->i2c_adap));
629 memcpy(&hdw->i2c_algo,&pvr2_i2c_algo_template,sizeof(hdw->i2c_algo));
630 strlcpy(hdw->i2c_adap.name,hdw->name,sizeof(hdw->i2c_adap.name));
631 hdw->i2c_adap.dev.parent = &hdw->usb_dev->dev;
632 hdw->i2c_adap.algo = &hdw->i2c_algo;
633 hdw->i2c_adap.algo_data = hdw;
634 hdw->i2c_linked = !0;
635 i2c_set_adapdata(&hdw->i2c_adap, &hdw->v4l2_dev);
636 i2c_add_adapter(&hdw->i2c_adap);
637 if (hdw->i2c_func[0x18] == i2c_24xxx_ir) {
638 /* Probe for a different type of IR receiver on this
639 device. This is really the only way to differentiate
640 older 24xxx devices from 24xxx variants that include an
641 IR blaster. If the IR blaster is present, the IR
642 receiver is part of that chip and thus we must disable
643 the emulated IR receiver. */
644 if (do_i2c_probe(hdw, 0x71)) {
645 pvr2_trace(PVR2_TRACE_INFO,
646 "Device has newer IR hardware;"
647 " disabling unneeded virtual IR device");
648 hdw->i2c_func[0x18] = NULL;
649 /* Remember that this is a different device... */
650 hdw->ir_scheme_active = PVR2_IR_SCHEME_24XXX_MCE;
653 if (i2c_scan) do_i2c_scan(hdw);
655 pvr2_i2c_register_ir(hdw);
658 void pvr2_i2c_core_done(struct pvr2_hdw *hdw)
660 if (hdw->i2c_linked) {
661 i2c_del_adapter(&hdw->i2c_adap);
667 Stuff for Emacs to see, in order to encourage consistent editing style:
668 *** Local Variables: ***
670 *** fill-column: 75 ***
672 *** c-basic-offset: 8 ***