1 /* 2 * linux/drivers/video/omap2/dss/sdi.c 3 * 4 * Copyright (C) 2009 Nokia Corporation 5 * Author: Tomi Valkeinen <tomi.valkeinen@nokia.com> 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License version 2 as published by 9 * the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 14 * more details. 15 * 16 * You should have received a copy of the GNU General Public License along with 17 * this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #define DSS_SUBSYS_NAME "SDI" 21 22 #include <linux/kernel.h> 23 #include <linux/delay.h> 24 #include <linux/err.h> 25 #include <linux/regulator/consumer.h> 26 #include <linux/export.h> 27 #include <linux/platform_device.h> 28 #include <linux/string.h> 29 #include <linux/of.h> 30 #include <linux/component.h> 31 32 #include "omapdss.h" 33 #include "dss.h" 34 35 static struct { 36 struct platform_device *pdev; 37 38 bool update_enabled; 39 struct regulator *vdds_sdi_reg; 40 41 struct dss_lcd_mgr_config mgr_config; 42 struct videomode vm; 43 int datapairs; 44 45 struct omap_dss_device output; 46 47 bool port_initialized; 48 } sdi; 49 50 struct sdi_clk_calc_ctx { 51 unsigned long pck_min, pck_max; 52 53 unsigned long fck; 54 struct dispc_clock_info dispc_cinfo; 55 }; 56 57 static bool dpi_calc_dispc_cb(int lckd, int pckd, unsigned long lck, 58 unsigned long pck, void *data) 59 { 60 struct sdi_clk_calc_ctx *ctx = data; 61 62 ctx->dispc_cinfo.lck_div = lckd; 63 ctx->dispc_cinfo.pck_div = pckd; 64 ctx->dispc_cinfo.lck = lck; 65 ctx->dispc_cinfo.pck = pck; 66 67 return true; 68 } 69 70 static bool dpi_calc_dss_cb(unsigned long fck, void *data) 71 { 72 struct sdi_clk_calc_ctx *ctx = data; 73 74 ctx->fck = fck; 75 76 return dispc_div_calc(fck, ctx->pck_min, ctx->pck_max, 77 dpi_calc_dispc_cb, ctx); 78 } 79 80 static int sdi_calc_clock_div(unsigned long pclk, 81 unsigned long *fck, 82 struct dispc_clock_info *dispc_cinfo) 83 { 84 int i; 85 struct sdi_clk_calc_ctx ctx; 86 87 /* 88 * DSS fclk gives us very few possibilities, so finding a good pixel 89 * clock may not be possible. We try multiple times to find the clock, 90 * each time widening the pixel clock range we look for, up to 91 * +/- 1MHz. 92 */ 93 94 for (i = 0; i < 10; ++i) { 95 bool ok; 96 97 memset(&ctx, 0, sizeof(ctx)); 98 if (pclk > 1000 * i * i * i) 99 ctx.pck_min = max(pclk - 1000 * i * i * i, 0lu); 100 else 101 ctx.pck_min = 0; 102 ctx.pck_max = pclk + 1000 * i * i * i; 103 104 ok = dss_div_calc(pclk, ctx.pck_min, dpi_calc_dss_cb, &ctx); 105 if (ok) { 106 *fck = ctx.fck; 107 *dispc_cinfo = ctx.dispc_cinfo; 108 return 0; 109 } 110 } 111 112 return -EINVAL; 113 } 114 115 static void sdi_config_lcd_manager(struct omap_dss_device *dssdev) 116 { 117 enum omap_channel channel = dssdev->dispc_channel; 118 119 sdi.mgr_config.io_pad_mode = DSS_IO_PAD_MODE_BYPASS; 120 121 sdi.mgr_config.stallmode = false; 122 sdi.mgr_config.fifohandcheck = false; 123 124 sdi.mgr_config.video_port_width = 24; 125 sdi.mgr_config.lcden_sig_polarity = 1; 126 127 dss_mgr_set_lcd_config(channel, &sdi.mgr_config); 128 } 129 130 static int sdi_display_enable(struct omap_dss_device *dssdev) 131 { 132 struct omap_dss_device *out = &sdi.output; 133 enum omap_channel channel = dssdev->dispc_channel; 134 struct videomode *vm = &sdi.vm; 135 unsigned long fck; 136 struct dispc_clock_info dispc_cinfo; 137 unsigned long pck; 138 int r; 139 140 if (!out->dispc_channel_connected) { 141 DSSERR("failed to enable display: no output/manager\n"); 142 return -ENODEV; 143 } 144 145 r = regulator_enable(sdi.vdds_sdi_reg); 146 if (r) 147 goto err_reg_enable; 148 149 r = dispc_runtime_get(); 150 if (r) 151 goto err_get_dispc; 152 153 /* 15.5.9.1.2 */ 154 vm->flags |= DISPLAY_FLAGS_PIXDATA_POSEDGE | DISPLAY_FLAGS_SYNC_POSEDGE; 155 156 r = sdi_calc_clock_div(vm->pixelclock, &fck, &dispc_cinfo); 157 if (r) 158 goto err_calc_clock_div; 159 160 sdi.mgr_config.clock_info = dispc_cinfo; 161 162 pck = fck / dispc_cinfo.lck_div / dispc_cinfo.pck_div; 163 164 if (pck != vm->pixelclock) { 165 DSSWARN("Could not find exact pixel clock. Requested %lu Hz, got %lu Hz\n", 166 vm->pixelclock, pck); 167 168 vm->pixelclock = pck; 169 } 170 171 172 dss_mgr_set_timings(channel, vm); 173 174 r = dss_set_fck_rate(fck); 175 if (r) 176 goto err_set_dss_clock_div; 177 178 sdi_config_lcd_manager(dssdev); 179 180 /* 181 * LCLK and PCLK divisors are located in shadow registers, and we 182 * normally write them to DISPC registers when enabling the output. 183 * However, SDI uses pck-free as source clock for its PLL, and pck-free 184 * is affected by the divisors. And as we need the PLL before enabling 185 * the output, we need to write the divisors early. 186 * 187 * It seems just writing to the DISPC register is enough, and we don't 188 * need to care about the shadow register mechanism for pck-free. The 189 * exact reason for this is unknown. 190 */ 191 dispc_mgr_set_clock_div(channel, &sdi.mgr_config.clock_info); 192 193 dss_sdi_init(sdi.datapairs); 194 r = dss_sdi_enable(); 195 if (r) 196 goto err_sdi_enable; 197 mdelay(2); 198 199 r = dss_mgr_enable(channel); 200 if (r) 201 goto err_mgr_enable; 202 203 return 0; 204 205 err_mgr_enable: 206 dss_sdi_disable(); 207 err_sdi_enable: 208 err_set_dss_clock_div: 209 err_calc_clock_div: 210 dispc_runtime_put(); 211 err_get_dispc: 212 regulator_disable(sdi.vdds_sdi_reg); 213 err_reg_enable: 214 return r; 215 } 216 217 static void sdi_display_disable(struct omap_dss_device *dssdev) 218 { 219 enum omap_channel channel = dssdev->dispc_channel; 220 221 dss_mgr_disable(channel); 222 223 dss_sdi_disable(); 224 225 dispc_runtime_put(); 226 227 regulator_disable(sdi.vdds_sdi_reg); 228 } 229 230 static void sdi_set_timings(struct omap_dss_device *dssdev, 231 struct videomode *vm) 232 { 233 sdi.vm = *vm; 234 } 235 236 static void sdi_get_timings(struct omap_dss_device *dssdev, 237 struct videomode *vm) 238 { 239 *vm = sdi.vm; 240 } 241 242 static int sdi_check_timings(struct omap_dss_device *dssdev, 243 struct videomode *vm) 244 { 245 enum omap_channel channel = dssdev->dispc_channel; 246 247 if (!dispc_mgr_timings_ok(channel, vm)) 248 return -EINVAL; 249 250 if (vm->pixelclock == 0) 251 return -EINVAL; 252 253 return 0; 254 } 255 256 static void sdi_set_datapairs(struct omap_dss_device *dssdev, int datapairs) 257 { 258 sdi.datapairs = datapairs; 259 } 260 261 static int sdi_init_regulator(void) 262 { 263 struct regulator *vdds_sdi; 264 265 if (sdi.vdds_sdi_reg) 266 return 0; 267 268 vdds_sdi = devm_regulator_get(&sdi.pdev->dev, "vdds_sdi"); 269 if (IS_ERR(vdds_sdi)) { 270 if (PTR_ERR(vdds_sdi) != -EPROBE_DEFER) 271 DSSERR("can't get VDDS_SDI regulator\n"); 272 return PTR_ERR(vdds_sdi); 273 } 274 275 sdi.vdds_sdi_reg = vdds_sdi; 276 277 return 0; 278 } 279 280 static int sdi_connect(struct omap_dss_device *dssdev, 281 struct omap_dss_device *dst) 282 { 283 enum omap_channel channel = dssdev->dispc_channel; 284 int r; 285 286 r = sdi_init_regulator(); 287 if (r) 288 return r; 289 290 r = dss_mgr_connect(channel, dssdev); 291 if (r) 292 return r; 293 294 r = omapdss_output_set_device(dssdev, dst); 295 if (r) { 296 DSSERR("failed to connect output to new device: %s\n", 297 dst->name); 298 dss_mgr_disconnect(channel, dssdev); 299 return r; 300 } 301 302 return 0; 303 } 304 305 static void sdi_disconnect(struct omap_dss_device *dssdev, 306 struct omap_dss_device *dst) 307 { 308 enum omap_channel channel = dssdev->dispc_channel; 309 310 WARN_ON(dst != dssdev->dst); 311 312 if (dst != dssdev->dst) 313 return; 314 315 omapdss_output_unset_device(dssdev); 316 317 dss_mgr_disconnect(channel, dssdev); 318 } 319 320 static const struct omapdss_sdi_ops sdi_ops = { 321 .connect = sdi_connect, 322 .disconnect = sdi_disconnect, 323 324 .enable = sdi_display_enable, 325 .disable = sdi_display_disable, 326 327 .check_timings = sdi_check_timings, 328 .set_timings = sdi_set_timings, 329 .get_timings = sdi_get_timings, 330 331 .set_datapairs = sdi_set_datapairs, 332 }; 333 334 static void sdi_init_output(struct platform_device *pdev) 335 { 336 struct omap_dss_device *out = &sdi.output; 337 338 out->dev = &pdev->dev; 339 out->id = OMAP_DSS_OUTPUT_SDI; 340 out->output_type = OMAP_DISPLAY_TYPE_SDI; 341 out->name = "sdi.0"; 342 out->dispc_channel = OMAP_DSS_CHANNEL_LCD; 343 /* We have SDI only on OMAP3, where it's on port 1 */ 344 out->port_num = 1; 345 out->ops.sdi = &sdi_ops; 346 out->owner = THIS_MODULE; 347 348 omapdss_register_output(out); 349 } 350 351 static void sdi_uninit_output(struct platform_device *pdev) 352 { 353 struct omap_dss_device *out = &sdi.output; 354 355 omapdss_unregister_output(out); 356 } 357 358 static int sdi_bind(struct device *dev, struct device *master, void *data) 359 { 360 struct platform_device *pdev = to_platform_device(dev); 361 362 sdi.pdev = pdev; 363 364 sdi_init_output(pdev); 365 366 return 0; 367 } 368 369 static void sdi_unbind(struct device *dev, struct device *master, void *data) 370 { 371 struct platform_device *pdev = to_platform_device(dev); 372 373 sdi_uninit_output(pdev); 374 } 375 376 static const struct component_ops sdi_component_ops = { 377 .bind = sdi_bind, 378 .unbind = sdi_unbind, 379 }; 380 381 static int sdi_probe(struct platform_device *pdev) 382 { 383 return component_add(&pdev->dev, &sdi_component_ops); 384 } 385 386 static int sdi_remove(struct platform_device *pdev) 387 { 388 component_del(&pdev->dev, &sdi_component_ops); 389 return 0; 390 } 391 392 static struct platform_driver omap_sdi_driver = { 393 .probe = sdi_probe, 394 .remove = sdi_remove, 395 .driver = { 396 .name = "omapdss_sdi", 397 .suppress_bind_attrs = true, 398 }, 399 }; 400 401 int __init sdi_init_platform_driver(void) 402 { 403 return platform_driver_register(&omap_sdi_driver); 404 } 405 406 void sdi_uninit_platform_driver(void) 407 { 408 platform_driver_unregister(&omap_sdi_driver); 409 } 410 411 int sdi_init_port(struct platform_device *pdev, struct device_node *port) 412 { 413 struct device_node *ep; 414 u32 datapairs; 415 int r; 416 417 ep = omapdss_of_get_next_endpoint(port, NULL); 418 if (!ep) 419 return 0; 420 421 r = of_property_read_u32(ep, "datapairs", &datapairs); 422 if (r) { 423 DSSERR("failed to parse datapairs\n"); 424 goto err_datapairs; 425 } 426 427 sdi.datapairs = datapairs; 428 429 of_node_put(ep); 430 431 sdi.pdev = pdev; 432 433 sdi_init_output(pdev); 434 435 sdi.port_initialized = true; 436 437 return 0; 438 439 err_datapairs: 440 of_node_put(ep); 441 442 return r; 443 } 444 445 void sdi_uninit_port(struct device_node *port) 446 { 447 if (!sdi.port_initialized) 448 return; 449 450 sdi_uninit_output(sdi.pdev); 451 } 452