1/*
2 * Copyright 2009 Red Hat Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 *
22 * Authors: Ben Skeggs
23 */
24
25#include <linux/module.h>
26
27#include "drmP.h"
28#include "nouveau_drv.h"
29#include "nouveau_i2c.h"
30#include "nouveau_hw.h"
31
32static void
33i2c_drive_scl(void *data, int state)
34{
35	struct nouveau_i2c_chan *port = data;
36	if (port->type == 0) {
37		u8 val = NVReadVgaCrtc(port->dev, 0, port->drive);
38		if (state) val |= 0x20;
39		else	   val &= 0xdf;
40		NVWriteVgaCrtc(port->dev, 0, port->drive, val | 0x01);
41	} else
42	if (port->type == 4) {
43		nv_mask(port->dev, port->drive, 0x2f, state ? 0x21 : 0x01);
44	} else
45	if (port->type == 5) {
46		if (state) port->state |= 0x01;
47		else	   port->state &= 0xfe;
48		nv_wr32(port->dev, port->drive, 4 | port->state);
49	}
50}
51
52static void
53i2c_drive_sda(void *data, int state)
54{
55	struct nouveau_i2c_chan *port = data;
56	if (port->type == 0) {
57		u8 val = NVReadVgaCrtc(port->dev, 0, port->drive);
58		if (state) val |= 0x10;
59		else	   val &= 0xef;
60		NVWriteVgaCrtc(port->dev, 0, port->drive, val | 0x01);
61	} else
62	if (port->type == 4) {
63		nv_mask(port->dev, port->drive, 0x1f, state ? 0x11 : 0x01);
64	} else
65	if (port->type == 5) {
66		if (state) port->state |= 0x02;
67		else	   port->state &= 0xfd;
68		nv_wr32(port->dev, port->drive, 4 | port->state);
69	}
70}
71
72static int
73i2c_sense_scl(void *data)
74{
75	struct nouveau_i2c_chan *port = data;
76	struct drm_nouveau_private *dev_priv = port->dev->dev_private;
77	if (port->type == 0) {
78		return !!(NVReadVgaCrtc(port->dev, 0, port->sense) & 0x04);
79	} else
80	if (port->type == 4) {
81		return !!(nv_rd32(port->dev, port->sense) & 0x00040000);
82	} else
83	if (port->type == 5) {
84		if (dev_priv->card_type < NV_D0)
85			return !!(nv_rd32(port->dev, port->sense) & 0x01);
86		else
87			return !!(nv_rd32(port->dev, port->sense) & 0x10);
88	}
89	return 0;
90}
91
92static int
93i2c_sense_sda(void *data)
94{
95	struct nouveau_i2c_chan *port = data;
96	struct drm_nouveau_private *dev_priv = port->dev->dev_private;
97	if (port->type == 0) {
98		return !!(NVReadVgaCrtc(port->dev, 0, port->sense) & 0x08);
99	} else
100	if (port->type == 4) {
101		return !!(nv_rd32(port->dev, port->sense) & 0x00080000);
102	} else
103	if (port->type == 5) {
104		if (dev_priv->card_type < NV_D0)
105			return !!(nv_rd32(port->dev, port->sense) & 0x02);
106		else
107			return !!(nv_rd32(port->dev, port->sense) & 0x20);
108	}
109	return 0;
110}
111
112static const uint32_t nv50_i2c_port[] = {
113	0x00e138, 0x00e150, 0x00e168, 0x00e180,
114	0x00e254, 0x00e274, 0x00e764, 0x00e780,
115	0x00e79c, 0x00e7b8
116};
117
118static u8 *
119i2c_table(struct drm_device *dev, u8 *version)
120{
121	u8 *dcb = dcb_table(dev), *i2c = NULL;
122	if (dcb) {
123		if (dcb[0] >= 0x15)
124			i2c = ROMPTR(dev, dcb[2]);
125		if (dcb[0] >= 0x30)
126			i2c = ROMPTR(dev, dcb[4]);
127	}
128
129	/* early revisions had no version number, use dcb version */
130	if (i2c) {
131		*version = dcb[0];
132		if (*version >= 0x30)
133			*version = i2c[0];
134	}
135
136	return i2c;
137}
138
139int
140nouveau_i2c_init(struct drm_device *dev)
141{
142	struct drm_nouveau_private *dev_priv = dev->dev_private;
143	struct nvbios *bios = &dev_priv->vbios;
144	struct nouveau_i2c_chan *port;
145	u8 version = 0x00, entries, recordlen;
146	u8 *i2c, *entry, legacy[2][4] = {};
147	int ret, i;
148
149	INIT_LIST_HEAD(&dev_priv->i2c_ports);
150
151	i2c = i2c_table(dev, &version);
152	if (!i2c) {
153		u8 *bmp = &bios->data[bios->offset];
154		if (bios->type != NVBIOS_BMP)
155			return -ENODEV;
156
157		legacy[0][0] = NV_CIO_CRE_DDC_WR__INDEX;
158		legacy[0][1] = NV_CIO_CRE_DDC_STATUS__INDEX;
159		legacy[1][0] = NV_CIO_CRE_DDC0_WR__INDEX;
160		legacy[1][1] = NV_CIO_CRE_DDC0_STATUS__INDEX;
161
162		/* BMP (from v4.0) has i2c info in the structure, it's in a
163		 * fixed location on earlier VBIOS
164		 */
165		if (bmp[5] < 4)
166			i2c = &bios->data[0x48];
167		else
168			i2c = &bmp[0x36];
169
170		if (i2c[4]) legacy[0][0] = i2c[4];
171		if (i2c[5]) legacy[0][1] = i2c[5];
172		if (i2c[6]) legacy[1][0] = i2c[6];
173		if (i2c[7]) legacy[1][1] = i2c[7];
174	}
175
176	if (version >= 0x30) {
177		entry     = i2c[1] + i2c;
178		entries   = i2c[2];
179		recordlen = i2c[3];
180	} else
181	if (version) {
182		entry     = i2c;
183		entries   = 16;
184		recordlen = 4;
185	} else {
186		entry     = legacy[0];
187		entries   = 2;
188		recordlen = 4;
189	}
190
191	for (i = 0; i < entries; i++, entry += recordlen) {
192		port = kzalloc(sizeof(*port), GFP_KERNEL);
193		if (port == NULL) {
194			nouveau_i2c_fini(dev);
195			return -ENOMEM;
196		}
197
198		port->type = entry[3];
199		if (version < 0x30) {
200			port->type &= 0x07;
201			if (port->type == 0x07)
202				port->type = 0xff;
203		}
204
205		if (port->type == 0xff) {
206			kfree(port);
207			continue;
208		}
209
210		switch (port->type) {
211		case 0: /* NV04:NV50 */
212			port->drive = entry[0];
213			port->sense = entry[1];
214			break;
215		case 4: /* NV4E */
216			port->drive = 0x600800 + entry[1];
217			port->sense = port->drive;
218			break;
219		case 5: /* NV50- */
220			port->drive = entry[0] & 0x0f;
221			if (dev_priv->card_type < NV_D0) {
222				if (port->drive >= ARRAY_SIZE(nv50_i2c_port))
223					break;
224				port->drive = nv50_i2c_port[port->drive];
225				port->sense = port->drive;
226			} else {
227				port->drive = 0x00d014 + (port->drive * 0x20);
228				port->sense = port->drive;
229			}
230			break;
231		case 6: /* NV50- DP AUX */
232			port->drive = entry[0];
233			port->sense = port->drive;
234			port->adapter.algo = &nouveau_dp_i2c_algo;
235			break;
236		default:
237			break;
238		}
239
240		if (!port->adapter.algo && !port->drive) {
241			NV_ERROR(dev, "I2C%d: type %d index %x/%x unknown\n",
242				 i, port->type, port->drive, port->sense);
243			kfree(port);
244			continue;
245		}
246
247		snprintf(port->adapter.name, sizeof(port->adapter.name),
248			 "nouveau-%s-%d", pci_name(dev->pdev), i);
249		port->adapter.owner = THIS_MODULE;
250		port->adapter.dev.parent = &dev->pdev->dev;
251		port->dev = dev;
252		port->index = i;
253		port->dcb = ROM32(entry[0]);
254		i2c_set_adapdata(&port->adapter, i2c);
255
256		if (port->adapter.algo != &nouveau_dp_i2c_algo) {
257			port->adapter.algo_data = &port->bit;
258			port->bit.udelay = 10;
259			port->bit.timeout = usecs_to_jiffies(2200);
260			port->bit.data = port;
261			port->bit.setsda = i2c_drive_sda;
262			port->bit.setscl = i2c_drive_scl;
263			port->bit.getsda = i2c_sense_sda;
264			port->bit.getscl = i2c_sense_scl;
265
266			i2c_drive_scl(port, 0);
267			i2c_drive_sda(port, 1);
268			i2c_drive_scl(port, 1);
269
270			ret = i2c_bit_add_bus(&port->adapter);
271		} else {
272			port->adapter.algo = &nouveau_dp_i2c_algo;
273			ret = i2c_add_adapter(&port->adapter);
274		}
275
276		if (ret) {
277			NV_ERROR(dev, "I2C%d: failed register: %d\n", i, ret);
278			kfree(port);
279			continue;
280		}
281
282		list_add_tail(&port->head, &dev_priv->i2c_ports);
283	}
284
285	return 0;
286}
287
288void
289nouveau_i2c_fini(struct drm_device *dev)
290{
291	struct drm_nouveau_private *dev_priv = dev->dev_private;
292	struct nouveau_i2c_chan *port, *tmp;
293
294	list_for_each_entry_safe(port, tmp, &dev_priv->i2c_ports, head) {
295		i2c_del_adapter(&port->adapter);
296		kfree(port);
297	}
298}
299
300struct nouveau_i2c_chan *
301nouveau_i2c_find(struct drm_device *dev, u8 index)
302{
303	struct drm_nouveau_private *dev_priv = dev->dev_private;
304	struct nouveau_i2c_chan *port;
305
306	if (index == NV_I2C_DEFAULT(0) ||
307	    index == NV_I2C_DEFAULT(1)) {
308		u8 version, *i2c = i2c_table(dev, &version);
309		if (i2c && version >= 0x30) {
310			if (index == NV_I2C_DEFAULT(0))
311				index = (i2c[4] & 0x0f);
312			else
313				index = (i2c[4] & 0xf0) >> 4;
314		} else {
315			index = 2;
316		}
317	}
318
319	list_for_each_entry(port, &dev_priv->i2c_ports, head) {
320		if (port->index == index)
321			break;
322	}
323
324	if (&port->head == &dev_priv->i2c_ports)
325		return NULL;
326
327	if (dev_priv->card_type >= NV_50 && (port->dcb & 0x00000100)) {
328		u32 reg = 0x00e500, val;
329		if (port->type == 6) {
330			reg += port->drive * 0x50;
331			val  = 0x2002;
332		} else {
333			reg += ((port->dcb & 0x1e00) >> 9) * 0x50;
334			val  = 0xe001;
335		}
336
337		/* nfi, but neither auxch or i2c work if it's 1 */
338		nv_mask(dev, reg + 0x0c, 0x00000001, 0x00000000);
339		/* nfi, but switches auxch vs normal i2c */
340		nv_mask(dev, reg + 0x00, 0x0000f003, val);
341	}
342
343	return port;
344}
345
346bool
347nouveau_probe_i2c_addr(struct nouveau_i2c_chan *i2c, int addr)
348{
349	uint8_t buf[] = { 0 };
350	struct i2c_msg msgs[] = {
351		{
352			.addr = addr,
353			.flags = 0,
354			.len = 1,
355			.buf = buf,
356		},
357		{
358			.addr = addr,
359			.flags = I2C_M_RD,
360			.len = 1,
361			.buf = buf,
362		}
363	};
364
365	return i2c_transfer(&i2c->adapter, msgs, 2) == 2;
366}
367
368int
369nouveau_i2c_identify(struct drm_device *dev, const char *what,
370		     struct i2c_board_info *info,
371		     bool (*match)(struct nouveau_i2c_chan *,
372				   struct i2c_board_info *),
373		     int index)
374{
375	struct nouveau_i2c_chan *i2c = nouveau_i2c_find(dev, index);
376	int i;
377
378	if (!i2c) {
379		NV_DEBUG(dev, "No bus when probing %s on %d\n", what, index);
380		return -ENODEV;
381	}
382
383	NV_DEBUG(dev, "Probing %ss on I2C bus: %d\n", what, i2c->index);
384	for (i = 0; info[i].addr; i++) {
385		if (nouveau_probe_i2c_addr(i2c, info[i].addr) &&
386		    (!match || match(i2c, &info[i]))) {
387			NV_INFO(dev, "Detected %s: %s\n", what, info[i].type);
388			return i;
389		}
390	}
391
392	NV_DEBUG(dev, "No devices found.\n");
393	return -ENODEV;
394}
395