1 /* 2 * Copyright 2007-8 Advanced Micro Devices, Inc. 3 * Copyright 2008 Red Hat Inc. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a 6 * copy of this software and associated documentation files (the "Software"), 7 * to deal in the Software without restriction, including without limitation 8 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 9 * and/or sell copies of the Software, and to permit persons to whom the 10 * Software is furnished to do so, subject to the following conditions: 11 * 12 * The above copyright notice and this permission notice shall be included in 13 * all copies or substantial portions of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 21 * OTHER DEALINGS IN THE SOFTWARE. 22 * 23 * Authors: Dave Airlie 24 * Alex Deucher 25 */ 26 27 #include <linux/export.h> 28 #include <linux/pci.h> 29 30 #include <drm/drm_edid.h> 31 #include <drm/amdgpu_drm.h> 32 #include "amdgpu.h" 33 #include "amdgpu_i2c.h" 34 #include "amdgpu_atombios.h" 35 #include "atom.h" 36 #include "atombios_dp.h" 37 #include "atombios_i2c.h" 38 39 /* bit banging i2c */ 40 static int amdgpu_i2c_pre_xfer(struct i2c_adapter *i2c_adap) 41 { 42 struct amdgpu_i2c_chan *i2c = i2c_get_adapdata(i2c_adap); 43 struct amdgpu_device *adev = drm_to_adev(i2c->dev); 44 struct amdgpu_i2c_bus_rec *rec = &i2c->rec; 45 uint32_t temp; 46 47 mutex_lock(&i2c->mutex); 48 49 /* switch the pads to ddc mode */ 50 if (rec->hw_capable) { 51 temp = RREG32(rec->mask_clk_reg); 52 temp &= ~(1 << 16); 53 WREG32(rec->mask_clk_reg, temp); 54 } 55 56 /* clear the output pin values */ 57 temp = RREG32(rec->a_clk_reg) & ~rec->a_clk_mask; 58 WREG32(rec->a_clk_reg, temp); 59 60 temp = RREG32(rec->a_data_reg) & ~rec->a_data_mask; 61 WREG32(rec->a_data_reg, temp); 62 63 /* set the pins to input */ 64 temp = RREG32(rec->en_clk_reg) & ~rec->en_clk_mask; 65 WREG32(rec->en_clk_reg, temp); 66 67 temp = RREG32(rec->en_data_reg) & ~rec->en_data_mask; 68 WREG32(rec->en_data_reg, temp); 69 70 /* mask the gpio pins for software use */ 71 temp = RREG32(rec->mask_clk_reg) | rec->mask_clk_mask; 72 WREG32(rec->mask_clk_reg, temp); 73 temp = RREG32(rec->mask_clk_reg); 74 75 temp = RREG32(rec->mask_data_reg) | rec->mask_data_mask; 76 WREG32(rec->mask_data_reg, temp); 77 temp = RREG32(rec->mask_data_reg); 78 79 return 0; 80 } 81 82 static void amdgpu_i2c_post_xfer(struct i2c_adapter *i2c_adap) 83 { 84 struct amdgpu_i2c_chan *i2c = i2c_get_adapdata(i2c_adap); 85 struct amdgpu_device *adev = drm_to_adev(i2c->dev); 86 struct amdgpu_i2c_bus_rec *rec = &i2c->rec; 87 uint32_t temp; 88 89 /* unmask the gpio pins for software use */ 90 temp = RREG32(rec->mask_clk_reg) & ~rec->mask_clk_mask; 91 WREG32(rec->mask_clk_reg, temp); 92 temp = RREG32(rec->mask_clk_reg); 93 94 temp = RREG32(rec->mask_data_reg) & ~rec->mask_data_mask; 95 WREG32(rec->mask_data_reg, temp); 96 temp = RREG32(rec->mask_data_reg); 97 98 mutex_unlock(&i2c->mutex); 99 } 100 101 static int amdgpu_i2c_get_clock(void *i2c_priv) 102 { 103 struct amdgpu_i2c_chan *i2c = i2c_priv; 104 struct amdgpu_device *adev = drm_to_adev(i2c->dev); 105 struct amdgpu_i2c_bus_rec *rec = &i2c->rec; 106 uint32_t val; 107 108 /* read the value off the pin */ 109 val = RREG32(rec->y_clk_reg); 110 val &= rec->y_clk_mask; 111 112 return (val != 0); 113 } 114 115 116 static int amdgpu_i2c_get_data(void *i2c_priv) 117 { 118 struct amdgpu_i2c_chan *i2c = i2c_priv; 119 struct amdgpu_device *adev = drm_to_adev(i2c->dev); 120 struct amdgpu_i2c_bus_rec *rec = &i2c->rec; 121 uint32_t val; 122 123 /* read the value off the pin */ 124 val = RREG32(rec->y_data_reg); 125 val &= rec->y_data_mask; 126 127 return (val != 0); 128 } 129 130 static void amdgpu_i2c_set_clock(void *i2c_priv, int clock) 131 { 132 struct amdgpu_i2c_chan *i2c = i2c_priv; 133 struct amdgpu_device *adev = drm_to_adev(i2c->dev); 134 struct amdgpu_i2c_bus_rec *rec = &i2c->rec; 135 uint32_t val; 136 137 /* set pin direction */ 138 val = RREG32(rec->en_clk_reg) & ~rec->en_clk_mask; 139 val |= clock ? 0 : rec->en_clk_mask; 140 WREG32(rec->en_clk_reg, val); 141 } 142 143 static void amdgpu_i2c_set_data(void *i2c_priv, int data) 144 { 145 struct amdgpu_i2c_chan *i2c = i2c_priv; 146 struct amdgpu_device *adev = drm_to_adev(i2c->dev); 147 struct amdgpu_i2c_bus_rec *rec = &i2c->rec; 148 uint32_t val; 149 150 /* set pin direction */ 151 val = RREG32(rec->en_data_reg) & ~rec->en_data_mask; 152 val |= data ? 0 : rec->en_data_mask; 153 WREG32(rec->en_data_reg, val); 154 } 155 156 static const struct i2c_algorithm amdgpu_atombios_i2c_algo = { 157 .master_xfer = amdgpu_atombios_i2c_xfer, 158 .functionality = amdgpu_atombios_i2c_func, 159 }; 160 161 struct amdgpu_i2c_chan *amdgpu_i2c_create(struct drm_device *dev, 162 const struct amdgpu_i2c_bus_rec *rec, 163 const char *name) 164 { 165 struct amdgpu_i2c_chan *i2c; 166 int ret; 167 168 /* don't add the mm_i2c bus unless hw_i2c is enabled */ 169 if (rec->mm_i2c && (amdgpu_hw_i2c == 0)) 170 return NULL; 171 172 i2c = kzalloc(sizeof(struct amdgpu_i2c_chan), GFP_KERNEL); 173 if (i2c == NULL) 174 return NULL; 175 176 i2c->rec = *rec; 177 i2c->adapter.owner = THIS_MODULE; 178 i2c->adapter.dev.parent = dev->dev; 179 i2c->dev = dev; 180 i2c_set_adapdata(&i2c->adapter, i2c); 181 mutex_init(&i2c->mutex); 182 if (rec->hw_capable && 183 amdgpu_hw_i2c) { 184 /* hw i2c using atom */ 185 snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), 186 "AMDGPU i2c hw bus %s", name); 187 i2c->adapter.algo = &amdgpu_atombios_i2c_algo; 188 ret = i2c_add_adapter(&i2c->adapter); 189 if (ret) 190 goto out_free; 191 } else { 192 /* set the amdgpu bit adapter */ 193 snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), 194 "AMDGPU i2c bit bus %s", name); 195 i2c->adapter.algo_data = &i2c->bit; 196 i2c->bit.pre_xfer = amdgpu_i2c_pre_xfer; 197 i2c->bit.post_xfer = amdgpu_i2c_post_xfer; 198 i2c->bit.setsda = amdgpu_i2c_set_data; 199 i2c->bit.setscl = amdgpu_i2c_set_clock; 200 i2c->bit.getsda = amdgpu_i2c_get_data; 201 i2c->bit.getscl = amdgpu_i2c_get_clock; 202 i2c->bit.udelay = 10; 203 i2c->bit.timeout = usecs_to_jiffies(2200); /* from VESA */ 204 i2c->bit.data = i2c; 205 ret = i2c_bit_add_bus(&i2c->adapter); 206 if (ret) { 207 DRM_ERROR("Failed to register bit i2c %s\n", name); 208 goto out_free; 209 } 210 } 211 212 return i2c; 213 out_free: 214 kfree(i2c); 215 return NULL; 216 217 } 218 219 void amdgpu_i2c_destroy(struct amdgpu_i2c_chan *i2c) 220 { 221 if (!i2c) 222 return; 223 WARN_ON(i2c->has_aux); 224 i2c_del_adapter(&i2c->adapter); 225 kfree(i2c); 226 } 227 228 /* Add the default buses */ 229 void amdgpu_i2c_init(struct amdgpu_device *adev) 230 { 231 if (amdgpu_hw_i2c) 232 DRM_INFO("hw_i2c forced on, you may experience display detection problems!\n"); 233 234 amdgpu_atombios_i2c_init(adev); 235 } 236 237 /* remove all the buses */ 238 void amdgpu_i2c_fini(struct amdgpu_device *adev) 239 { 240 int i; 241 242 for (i = 0; i < AMDGPU_MAX_I2C_BUS; i++) { 243 if (adev->i2c_bus[i]) { 244 amdgpu_i2c_destroy(adev->i2c_bus[i]); 245 adev->i2c_bus[i] = NULL; 246 } 247 } 248 } 249 250 /* Add additional buses */ 251 void amdgpu_i2c_add(struct amdgpu_device *adev, 252 const struct amdgpu_i2c_bus_rec *rec, 253 const char *name) 254 { 255 struct drm_device *dev = adev_to_drm(adev); 256 int i; 257 258 for (i = 0; i < AMDGPU_MAX_I2C_BUS; i++) { 259 if (!adev->i2c_bus[i]) { 260 adev->i2c_bus[i] = amdgpu_i2c_create(dev, rec, name); 261 return; 262 } 263 } 264 } 265 266 /* looks up bus based on id */ 267 struct amdgpu_i2c_chan * 268 amdgpu_i2c_lookup(struct amdgpu_device *adev, 269 const struct amdgpu_i2c_bus_rec *i2c_bus) 270 { 271 int i; 272 273 for (i = 0; i < AMDGPU_MAX_I2C_BUS; i++) { 274 if (adev->i2c_bus[i] && 275 (adev->i2c_bus[i]->rec.i2c_id == i2c_bus->i2c_id)) { 276 return adev->i2c_bus[i]; 277 } 278 } 279 return NULL; 280 } 281 282 static void amdgpu_i2c_get_byte(struct amdgpu_i2c_chan *i2c_bus, 283 u8 slave_addr, 284 u8 addr, 285 u8 *val) 286 { 287 u8 out_buf[2]; 288 u8 in_buf[2]; 289 struct i2c_msg msgs[] = { 290 { 291 .addr = slave_addr, 292 .flags = 0, 293 .len = 1, 294 .buf = out_buf, 295 }, 296 { 297 .addr = slave_addr, 298 .flags = I2C_M_RD, 299 .len = 1, 300 .buf = in_buf, 301 } 302 }; 303 304 out_buf[0] = addr; 305 out_buf[1] = 0; 306 307 if (i2c_transfer(&i2c_bus->adapter, msgs, 2) == 2) { 308 *val = in_buf[0]; 309 DRM_DEBUG("val = 0x%02x\n", *val); 310 } else { 311 DRM_DEBUG("i2c 0x%02x 0x%02x read failed\n", 312 addr, *val); 313 } 314 } 315 316 static void amdgpu_i2c_put_byte(struct amdgpu_i2c_chan *i2c_bus, 317 u8 slave_addr, 318 u8 addr, 319 u8 val) 320 { 321 uint8_t out_buf[2]; 322 struct i2c_msg msg = { 323 .addr = slave_addr, 324 .flags = 0, 325 .len = 2, 326 .buf = out_buf, 327 }; 328 329 out_buf[0] = addr; 330 out_buf[1] = val; 331 332 if (i2c_transfer(&i2c_bus->adapter, &msg, 1) != 1) 333 DRM_DEBUG("i2c 0x%02x 0x%02x write failed\n", 334 addr, val); 335 } 336 337 /* ddc router switching */ 338 void 339 amdgpu_i2c_router_select_ddc_port(const struct amdgpu_connector *amdgpu_connector) 340 { 341 u8 val = 0; 342 343 if (!amdgpu_connector->router.ddc_valid) 344 return; 345 346 if (!amdgpu_connector->router_bus) 347 return; 348 349 amdgpu_i2c_get_byte(amdgpu_connector->router_bus, 350 amdgpu_connector->router.i2c_addr, 351 0x3, &val); 352 val &= ~amdgpu_connector->router.ddc_mux_control_pin; 353 amdgpu_i2c_put_byte(amdgpu_connector->router_bus, 354 amdgpu_connector->router.i2c_addr, 355 0x3, val); 356 amdgpu_i2c_get_byte(amdgpu_connector->router_bus, 357 amdgpu_connector->router.i2c_addr, 358 0x1, &val); 359 val &= ~amdgpu_connector->router.ddc_mux_control_pin; 360 val |= amdgpu_connector->router.ddc_mux_state; 361 amdgpu_i2c_put_byte(amdgpu_connector->router_bus, 362 amdgpu_connector->router.i2c_addr, 363 0x1, val); 364 } 365 366 /* clock/data router switching */ 367 void 368 amdgpu_i2c_router_select_cd_port(const struct amdgpu_connector *amdgpu_connector) 369 { 370 u8 val; 371 372 if (!amdgpu_connector->router.cd_valid) 373 return; 374 375 if (!amdgpu_connector->router_bus) 376 return; 377 378 amdgpu_i2c_get_byte(amdgpu_connector->router_bus, 379 amdgpu_connector->router.i2c_addr, 380 0x3, &val); 381 val &= ~amdgpu_connector->router.cd_mux_control_pin; 382 amdgpu_i2c_put_byte(amdgpu_connector->router_bus, 383 amdgpu_connector->router.i2c_addr, 384 0x3, val); 385 amdgpu_i2c_get_byte(amdgpu_connector->router_bus, 386 amdgpu_connector->router.i2c_addr, 387 0x1, &val); 388 val &= ~amdgpu_connector->router.cd_mux_control_pin; 389 val |= amdgpu_connector->router.cd_mux_state; 390 amdgpu_i2c_put_byte(amdgpu_connector->router_bus, 391 amdgpu_connector->router.i2c_addr, 392 0x1, val); 393 } 394