OMAPDSS: VENC: fix NULL pointer dereference in DSS2 VENC sysfs debug attr on OMAP4
[zen-stable.git] / drivers / gpu / drm / i2c / sil164_drv.c
blobb7d45ab4ba699d12590ab74489ebf6f58ba25cfe
1 /*
2 * Copyright (C) 2010 Francisco Jerez.
3 * All Rights Reserved.
5 * Permission is hereby granted, free of charge, to any person obtaining
6 * a copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sublicense, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
13 * The above copyright notice and this permission notice (including the
14 * next paragraph) shall be included in all copies or substantial
15 * portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
20 * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
27 #include <linux/module.h>
29 #include "drmP.h"
30 #include "drm_crtc_helper.h"
31 #include "drm_encoder_slave.h"
32 #include "i2c/sil164.h"
34 struct sil164_priv {
35 struct sil164_encoder_params config;
36 struct i2c_client *duallink_slave;
38 uint8_t saved_state[0x10];
39 uint8_t saved_slave_state[0x10];
42 #define to_sil164_priv(x) \
43 ((struct sil164_priv *)to_encoder_slave(x)->slave_priv)
45 #define sil164_dbg(client, format, ...) do { \
46 if (drm_debug & DRM_UT_KMS) \
47 dev_printk(KERN_DEBUG, &client->dev, \
48 "%s: " format, __func__, ## __VA_ARGS__); \
49 } while (0)
50 #define sil164_info(client, format, ...) \
51 dev_info(&client->dev, format, __VA_ARGS__)
52 #define sil164_err(client, format, ...) \
53 dev_err(&client->dev, format, __VA_ARGS__)
55 #define SIL164_I2C_ADDR_MASTER 0x38
56 #define SIL164_I2C_ADDR_SLAVE 0x39
58 /* HW register definitions */
60 #define SIL164_VENDOR_LO 0x0
61 #define SIL164_VENDOR_HI 0x1
62 #define SIL164_DEVICE_LO 0x2
63 #define SIL164_DEVICE_HI 0x3
64 #define SIL164_REVISION 0x4
65 #define SIL164_FREQ_MIN 0x6
66 #define SIL164_FREQ_MAX 0x7
67 #define SIL164_CONTROL0 0x8
68 # define SIL164_CONTROL0_POWER_ON 0x01
69 # define SIL164_CONTROL0_EDGE_RISING 0x02
70 # define SIL164_CONTROL0_INPUT_24BIT 0x04
71 # define SIL164_CONTROL0_DUAL_EDGE 0x08
72 # define SIL164_CONTROL0_HSYNC_ON 0x10
73 # define SIL164_CONTROL0_VSYNC_ON 0x20
74 #define SIL164_DETECT 0x9
75 # define SIL164_DETECT_INTR_STAT 0x01
76 # define SIL164_DETECT_HOTPLUG_STAT 0x02
77 # define SIL164_DETECT_RECEIVER_STAT 0x04
78 # define SIL164_DETECT_INTR_MODE_RECEIVER 0x00
79 # define SIL164_DETECT_INTR_MODE_HOTPLUG 0x08
80 # define SIL164_DETECT_OUT_MODE_HIGH 0x00
81 # define SIL164_DETECT_OUT_MODE_INTR 0x10
82 # define SIL164_DETECT_OUT_MODE_RECEIVER 0x20
83 # define SIL164_DETECT_OUT_MODE_HOTPLUG 0x30
84 # define SIL164_DETECT_VSWING_STAT 0x80
85 #define SIL164_CONTROL1 0xa
86 # define SIL164_CONTROL1_DESKEW_ENABLE 0x10
87 # define SIL164_CONTROL1_DESKEW_INCR_SHIFT 5
88 #define SIL164_GPIO 0xb
89 #define SIL164_CONTROL2 0xc
90 # define SIL164_CONTROL2_FILTER_ENABLE 0x01
91 # define SIL164_CONTROL2_FILTER_SETTING_SHIFT 1
92 # define SIL164_CONTROL2_DUALLINK_MASTER 0x40
93 # define SIL164_CONTROL2_SYNC_CONT 0x80
94 #define SIL164_DUALLINK 0xd
95 # define SIL164_DUALLINK_ENABLE 0x10
96 # define SIL164_DUALLINK_SKEW_SHIFT 5
97 #define SIL164_PLLZONE 0xe
98 # define SIL164_PLLZONE_STAT 0x08
99 # define SIL164_PLLZONE_FORCE_ON 0x10
100 # define SIL164_PLLZONE_FORCE_HIGH 0x20
102 /* HW access functions */
104 static void
105 sil164_write(struct i2c_client *client, uint8_t addr, uint8_t val)
107 uint8_t buf[] = {addr, val};
108 int ret;
110 ret = i2c_master_send(client, buf, ARRAY_SIZE(buf));
111 if (ret < 0)
112 sil164_err(client, "Error %d writing to subaddress 0x%x\n",
113 ret, addr);
116 static uint8_t
117 sil164_read(struct i2c_client *client, uint8_t addr)
119 uint8_t val;
120 int ret;
122 ret = i2c_master_send(client, &addr, sizeof(addr));
123 if (ret < 0)
124 goto fail;
126 ret = i2c_master_recv(client, &val, sizeof(val));
127 if (ret < 0)
128 goto fail;
130 return val;
132 fail:
133 sil164_err(client, "Error %d reading from subaddress 0x%x\n",
134 ret, addr);
135 return 0;
138 static void
139 sil164_save_state(struct i2c_client *client, uint8_t *state)
141 int i;
143 for (i = 0x8; i <= 0xe; i++)
144 state[i] = sil164_read(client, i);
147 static void
148 sil164_restore_state(struct i2c_client *client, uint8_t *state)
150 int i;
152 for (i = 0x8; i <= 0xe; i++)
153 sil164_write(client, i, state[i]);
156 static void
157 sil164_set_power_state(struct i2c_client *client, bool on)
159 uint8_t control0 = sil164_read(client, SIL164_CONTROL0);
161 if (on)
162 control0 |= SIL164_CONTROL0_POWER_ON;
163 else
164 control0 &= ~SIL164_CONTROL0_POWER_ON;
166 sil164_write(client, SIL164_CONTROL0, control0);
169 static void
170 sil164_init_state(struct i2c_client *client,
171 struct sil164_encoder_params *config,
172 bool duallink)
174 sil164_write(client, SIL164_CONTROL0,
175 SIL164_CONTROL0_HSYNC_ON |
176 SIL164_CONTROL0_VSYNC_ON |
177 (config->input_edge ? SIL164_CONTROL0_EDGE_RISING : 0) |
178 (config->input_width ? SIL164_CONTROL0_INPUT_24BIT : 0) |
179 (config->input_dual ? SIL164_CONTROL0_DUAL_EDGE : 0));
181 sil164_write(client, SIL164_DETECT,
182 SIL164_DETECT_INTR_STAT |
183 SIL164_DETECT_OUT_MODE_RECEIVER);
185 sil164_write(client, SIL164_CONTROL1,
186 (config->input_skew ? SIL164_CONTROL1_DESKEW_ENABLE : 0) |
187 (((config->input_skew + 4) & 0x7)
188 << SIL164_CONTROL1_DESKEW_INCR_SHIFT));
190 sil164_write(client, SIL164_CONTROL2,
191 SIL164_CONTROL2_SYNC_CONT |
192 (config->pll_filter ? 0 : SIL164_CONTROL2_FILTER_ENABLE) |
193 (4 << SIL164_CONTROL2_FILTER_SETTING_SHIFT));
195 sil164_write(client, SIL164_PLLZONE, 0);
197 if (duallink)
198 sil164_write(client, SIL164_DUALLINK,
199 SIL164_DUALLINK_ENABLE |
200 (((config->duallink_skew + 4) & 0x7)
201 << SIL164_DUALLINK_SKEW_SHIFT));
202 else
203 sil164_write(client, SIL164_DUALLINK, 0);
206 /* DRM encoder functions */
208 static void
209 sil164_encoder_set_config(struct drm_encoder *encoder, void *params)
211 struct sil164_priv *priv = to_sil164_priv(encoder);
213 priv->config = *(struct sil164_encoder_params *)params;
216 static void
217 sil164_encoder_dpms(struct drm_encoder *encoder, int mode)
219 struct sil164_priv *priv = to_sil164_priv(encoder);
220 bool on = (mode == DRM_MODE_DPMS_ON);
221 bool duallink = (on && encoder->crtc->mode.clock > 165000);
223 sil164_set_power_state(drm_i2c_encoder_get_client(encoder), on);
225 if (priv->duallink_slave)
226 sil164_set_power_state(priv->duallink_slave, duallink);
229 static void
230 sil164_encoder_save(struct drm_encoder *encoder)
232 struct sil164_priv *priv = to_sil164_priv(encoder);
234 sil164_save_state(drm_i2c_encoder_get_client(encoder),
235 priv->saved_state);
237 if (priv->duallink_slave)
238 sil164_save_state(priv->duallink_slave,
239 priv->saved_slave_state);
242 static void
243 sil164_encoder_restore(struct drm_encoder *encoder)
245 struct sil164_priv *priv = to_sil164_priv(encoder);
247 sil164_restore_state(drm_i2c_encoder_get_client(encoder),
248 priv->saved_state);
250 if (priv->duallink_slave)
251 sil164_restore_state(priv->duallink_slave,
252 priv->saved_slave_state);
255 static bool
256 sil164_encoder_mode_fixup(struct drm_encoder *encoder,
257 struct drm_display_mode *mode,
258 struct drm_display_mode *adjusted_mode)
260 return true;
263 static int
264 sil164_encoder_mode_valid(struct drm_encoder *encoder,
265 struct drm_display_mode *mode)
267 struct sil164_priv *priv = to_sil164_priv(encoder);
269 if (mode->clock < 32000)
270 return MODE_CLOCK_LOW;
272 if (mode->clock > 330000 ||
273 (mode->clock > 165000 && !priv->duallink_slave))
274 return MODE_CLOCK_HIGH;
276 return MODE_OK;
279 static void
280 sil164_encoder_mode_set(struct drm_encoder *encoder,
281 struct drm_display_mode *mode,
282 struct drm_display_mode *adjusted_mode)
284 struct sil164_priv *priv = to_sil164_priv(encoder);
285 bool duallink = adjusted_mode->clock > 165000;
287 sil164_init_state(drm_i2c_encoder_get_client(encoder),
288 &priv->config, duallink);
290 if (priv->duallink_slave)
291 sil164_init_state(priv->duallink_slave,
292 &priv->config, duallink);
294 sil164_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
297 static enum drm_connector_status
298 sil164_encoder_detect(struct drm_encoder *encoder,
299 struct drm_connector *connector)
301 struct i2c_client *client = drm_i2c_encoder_get_client(encoder);
303 if (sil164_read(client, SIL164_DETECT) & SIL164_DETECT_HOTPLUG_STAT)
304 return connector_status_connected;
305 else
306 return connector_status_disconnected;
309 static int
310 sil164_encoder_get_modes(struct drm_encoder *encoder,
311 struct drm_connector *connector)
313 return 0;
316 static int
317 sil164_encoder_create_resources(struct drm_encoder *encoder,
318 struct drm_connector *connector)
320 return 0;
323 static int
324 sil164_encoder_set_property(struct drm_encoder *encoder,
325 struct drm_connector *connector,
326 struct drm_property *property,
327 uint64_t val)
329 return 0;
332 static void
333 sil164_encoder_destroy(struct drm_encoder *encoder)
335 struct sil164_priv *priv = to_sil164_priv(encoder);
337 if (priv->duallink_slave)
338 i2c_unregister_device(priv->duallink_slave);
340 kfree(priv);
341 drm_i2c_encoder_destroy(encoder);
344 static struct drm_encoder_slave_funcs sil164_encoder_funcs = {
345 .set_config = sil164_encoder_set_config,
346 .destroy = sil164_encoder_destroy,
347 .dpms = sil164_encoder_dpms,
348 .save = sil164_encoder_save,
349 .restore = sil164_encoder_restore,
350 .mode_fixup = sil164_encoder_mode_fixup,
351 .mode_valid = sil164_encoder_mode_valid,
352 .mode_set = sil164_encoder_mode_set,
353 .detect = sil164_encoder_detect,
354 .get_modes = sil164_encoder_get_modes,
355 .create_resources = sil164_encoder_create_resources,
356 .set_property = sil164_encoder_set_property,
359 /* I2C driver functions */
361 static int
362 sil164_probe(struct i2c_client *client, const struct i2c_device_id *id)
364 int vendor = sil164_read(client, SIL164_VENDOR_HI) << 8 |
365 sil164_read(client, SIL164_VENDOR_LO);
366 int device = sil164_read(client, SIL164_DEVICE_HI) << 8 |
367 sil164_read(client, SIL164_DEVICE_LO);
368 int rev = sil164_read(client, SIL164_REVISION);
370 if (vendor != 0x1 || device != 0x6) {
371 sil164_dbg(client, "Unknown device %x:%x.%x\n",
372 vendor, device, rev);
373 return -ENODEV;
376 sil164_info(client, "Detected device %x:%x.%x\n",
377 vendor, device, rev);
379 return 0;
382 static int
383 sil164_remove(struct i2c_client *client)
385 return 0;
388 static struct i2c_client *
389 sil164_detect_slave(struct i2c_client *client)
391 struct i2c_adapter *adap = client->adapter;
392 struct i2c_msg msg = {
393 .addr = SIL164_I2C_ADDR_SLAVE,
394 .len = 0,
396 const struct i2c_board_info info = {
397 I2C_BOARD_INFO("sil164", SIL164_I2C_ADDR_SLAVE)
400 if (i2c_transfer(adap, &msg, 1) != 1) {
401 sil164_dbg(adap, "No dual-link slave found.");
402 return NULL;
405 return i2c_new_device(adap, &info);
408 static int
409 sil164_encoder_init(struct i2c_client *client,
410 struct drm_device *dev,
411 struct drm_encoder_slave *encoder)
413 struct sil164_priv *priv;
415 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
416 if (!priv)
417 return -ENOMEM;
419 encoder->slave_priv = priv;
420 encoder->slave_funcs = &sil164_encoder_funcs;
422 priv->duallink_slave = sil164_detect_slave(client);
424 return 0;
427 static struct i2c_device_id sil164_ids[] = {
428 { "sil164", 0 },
431 MODULE_DEVICE_TABLE(i2c, sil164_ids);
433 static struct drm_i2c_encoder_driver sil164_driver = {
434 .i2c_driver = {
435 .probe = sil164_probe,
436 .remove = sil164_remove,
437 .driver = {
438 .name = "sil164",
440 .id_table = sil164_ids,
442 .encoder_init = sil164_encoder_init,
445 /* Module initialization */
447 static int __init
448 sil164_init(void)
450 return drm_i2c_encoder_register(THIS_MODULE, &sil164_driver);
453 static void __exit
454 sil164_exit(void)
456 drm_i2c_encoder_unregister(&sil164_driver);
459 MODULE_AUTHOR("Francisco Jerez <currojerez@riseup.net>");
460 MODULE_DESCRIPTION("Silicon Image sil164 TMDS transmitter driver");
461 MODULE_LICENSE("GPL and additional rights");
463 module_init(sil164_init);
464 module_exit(sil164_exit);