1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/drivers/video/vt8500lcdfb.c 4 * 5 * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com> 6 * 7 * Based on skeletonfb.c and pxafb.c 8 */ 9 10 #include <linux/delay.h> 11 #include <linux/dma-mapping.h> 12 #include <linux/errno.h> 13 #include <linux/fb.h> 14 #include <linux/init.h> 15 #include <linux/interrupt.h> 16 #include <linux/io.h> 17 #include <linux/kernel.h> 18 #include <linux/mm.h> 19 #include <linux/module.h> 20 #include <linux/platform_device.h> 21 #include <linux/slab.h> 22 #include <linux/string.h> 23 #include <linux/wait.h> 24 #include <video/of_display_timing.h> 25 26 #include "vt8500lcdfb.h" 27 #include "wmt_ge_rops.h" 28 29 #ifdef CONFIG_OF 30 #include <linux/of.h> 31 #include <linux/of_fdt.h> 32 #include <linux/memblock.h> 33 #endif 34 35 36 #define to_vt8500lcd_info(__info) container_of(__info, \ 37 struct vt8500lcd_info, fb) 38 39 static int vt8500lcd_set_par(struct fb_info *info) 40 { 41 struct vt8500lcd_info *fbi = to_vt8500lcd_info(info); 42 int reg_bpp = 5; /* 16bpp */ 43 int i; 44 unsigned long control0; 45 46 if (!fbi) 47 return -EINVAL; 48 49 if (info->var.bits_per_pixel <= 8) { 50 /* palettized */ 51 info->var.red.offset = 0; 52 info->var.red.length = info->var.bits_per_pixel; 53 info->var.red.msb_right = 0; 54 55 info->var.green.offset = 0; 56 info->var.green.length = info->var.bits_per_pixel; 57 info->var.green.msb_right = 0; 58 59 info->var.blue.offset = 0; 60 info->var.blue.length = info->var.bits_per_pixel; 61 info->var.blue.msb_right = 0; 62 63 info->var.transp.offset = 0; 64 info->var.transp.length = 0; 65 info->var.transp.msb_right = 0; 66 67 info->fix.visual = FB_VISUAL_PSEUDOCOLOR; 68 info->fix.line_length = info->var.xres_virtual / 69 (8/info->var.bits_per_pixel); 70 } else { 71 /* non-palettized */ 72 info->var.transp.offset = 0; 73 info->var.transp.length = 0; 74 info->var.transp.msb_right = 0; 75 76 if (info->var.bits_per_pixel == 16) { 77 /* RGB565 */ 78 info->var.red.offset = 11; 79 info->var.red.length = 5; 80 info->var.red.msb_right = 0; 81 info->var.green.offset = 5; 82 info->var.green.length = 6; 83 info->var.green.msb_right = 0; 84 info->var.blue.offset = 0; 85 info->var.blue.length = 5; 86 info->var.blue.msb_right = 0; 87 } else { 88 /* Equal depths per channel */ 89 info->var.red.offset = info->var.bits_per_pixel 90 * 2 / 3; 91 info->var.red.length = info->var.bits_per_pixel / 3; 92 info->var.red.msb_right = 0; 93 info->var.green.offset = info->var.bits_per_pixel / 3; 94 info->var.green.length = info->var.bits_per_pixel / 3; 95 info->var.green.msb_right = 0; 96 info->var.blue.offset = 0; 97 info->var.blue.length = info->var.bits_per_pixel / 3; 98 info->var.blue.msb_right = 0; 99 } 100 101 info->fix.visual = FB_VISUAL_TRUECOLOR; 102 info->fix.line_length = info->var.bits_per_pixel > 16 ? 103 info->var.xres_virtual << 2 : 104 info->var.xres_virtual << 1; 105 } 106 107 for (i = 0; i < 8; i++) { 108 if (bpp_values[i] == info->var.bits_per_pixel) 109 reg_bpp = i; 110 } 111 112 control0 = readl(fbi->regbase) & ~0xf; 113 writel(0, fbi->regbase); 114 while (readl(fbi->regbase + 0x38) & 0x10) 115 /* wait */; 116 writel((((info->var.hsync_len - 1) & 0x3f) << 26) 117 | ((info->var.left_margin & 0xff) << 18) 118 | (((info->var.xres - 1) & 0x3ff) << 8) 119 | (info->var.right_margin & 0xff), fbi->regbase + 0x4); 120 writel((((info->var.vsync_len - 1) & 0x3f) << 26) 121 | ((info->var.upper_margin & 0xff) << 18) 122 | (((info->var.yres - 1) & 0x3ff) << 8) 123 | (info->var.lower_margin & 0xff), fbi->regbase + 0x8); 124 writel((((info->var.yres - 1) & 0x400) << 2) 125 | ((info->var.xres - 1) & 0x400), fbi->regbase + 0x10); 126 writel(0x80000000, fbi->regbase + 0x20); 127 writel(control0 | (reg_bpp << 1) | 0x100, fbi->regbase); 128 129 return 0; 130 } 131 132 static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf) 133 { 134 chan &= 0xffff; 135 chan >>= 16 - bf->length; 136 return chan << bf->offset; 137 } 138 139 static int vt8500lcd_setcolreg(unsigned regno, unsigned red, unsigned green, 140 unsigned blue, unsigned transp, 141 struct fb_info *info) { 142 struct vt8500lcd_info *fbi = to_vt8500lcd_info(info); 143 int ret = 1; 144 unsigned int val; 145 if (regno >= 256) 146 return -EINVAL; 147 148 if (info->var.grayscale) 149 red = green = blue = 150 (19595 * red + 38470 * green + 7471 * blue) >> 16; 151 152 switch (fbi->fb.fix.visual) { 153 case FB_VISUAL_TRUECOLOR: 154 if (regno < 16) { 155 u32 *pal = fbi->fb.pseudo_palette; 156 157 val = chan_to_field(red, &fbi->fb.var.red); 158 val |= chan_to_field(green, &fbi->fb.var.green); 159 val |= chan_to_field(blue, &fbi->fb.var.blue); 160 161 pal[regno] = val; 162 ret = 0; 163 } 164 break; 165 166 case FB_VISUAL_STATIC_PSEUDOCOLOR: 167 case FB_VISUAL_PSEUDOCOLOR: 168 writew((red & 0xf800) 169 | ((green >> 5) & 0x7e0) 170 | ((blue >> 11) & 0x1f), 171 fbi->palette_cpu + sizeof(u16) * regno); 172 break; 173 } 174 175 return ret; 176 } 177 178 static int vt8500lcd_ioctl(struct fb_info *info, unsigned int cmd, 179 unsigned long arg) 180 { 181 int ret = 0; 182 struct vt8500lcd_info *fbi = to_vt8500lcd_info(info); 183 184 if (cmd == FBIO_WAITFORVSYNC) { 185 /* Unmask End of Frame interrupt */ 186 writel(0xffffffff ^ (1 << 3), fbi->regbase + 0x3c); 187 ret = wait_event_interruptible_timeout(fbi->wait, 188 readl(fbi->regbase + 0x38) & (1 << 3), HZ / 10); 189 /* Mask back to reduce unwanted interrupt traffic */ 190 writel(0xffffffff, fbi->regbase + 0x3c); 191 if (ret < 0) 192 return ret; 193 if (ret == 0) 194 return -ETIMEDOUT; 195 } 196 197 return ret; 198 } 199 200 static int vt8500lcd_pan_display(struct fb_var_screeninfo *var, 201 struct fb_info *info) 202 { 203 unsigned pixlen = info->fix.line_length / info->var.xres_virtual; 204 unsigned off = pixlen * var->xoffset 205 + info->fix.line_length * var->yoffset; 206 struct vt8500lcd_info *fbi = to_vt8500lcd_info(info); 207 208 writel((1 << 31) 209 | (((info->var.xres_virtual - info->var.xres) * pixlen / 4) << 20) 210 | (off >> 2), fbi->regbase + 0x20); 211 return 0; 212 } 213 214 /* 215 * vt8500lcd_blank(): 216 * Blank the display by setting all palette values to zero. Note, 217 * True Color modes do not really use the palette, so this will not 218 * blank the display in all modes. 219 */ 220 static int vt8500lcd_blank(int blank, struct fb_info *info) 221 { 222 int i; 223 224 switch (blank) { 225 case FB_BLANK_POWERDOWN: 226 case FB_BLANK_VSYNC_SUSPEND: 227 case FB_BLANK_HSYNC_SUSPEND: 228 case FB_BLANK_NORMAL: 229 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR || 230 info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR) 231 for (i = 0; i < 256; i++) 232 vt8500lcd_setcolreg(i, 0, 0, 0, 0, info); 233 fallthrough; 234 case FB_BLANK_UNBLANK: 235 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR || 236 info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR) 237 fb_set_cmap(&info->cmap, info); 238 } 239 return 0; 240 } 241 242 static const struct fb_ops vt8500lcd_ops = { 243 .owner = THIS_MODULE, 244 __FB_DEFAULT_DMAMEM_OPS_RDWR, 245 .fb_set_par = vt8500lcd_set_par, 246 .fb_setcolreg = vt8500lcd_setcolreg, 247 .fb_fillrect = wmt_ge_fillrect, 248 .fb_copyarea = wmt_ge_copyarea, 249 .fb_imageblit = sys_imageblit, 250 .fb_sync = wmt_ge_sync, 251 .fb_ioctl = vt8500lcd_ioctl, 252 .fb_pan_display = vt8500lcd_pan_display, 253 .fb_blank = vt8500lcd_blank, 254 // .fb_mmap needs DMA mmap 255 }; 256 257 static irqreturn_t vt8500lcd_handle_irq(int irq, void *dev_id) 258 { 259 struct vt8500lcd_info *fbi = dev_id; 260 261 if (readl(fbi->regbase + 0x38) & (1 << 3)) 262 wake_up_interruptible(&fbi->wait); 263 264 writel(0xffffffff, fbi->regbase + 0x38); 265 return IRQ_HANDLED; 266 } 267 268 static int vt8500lcd_probe(struct platform_device *pdev) 269 { 270 struct vt8500lcd_info *fbi; 271 struct resource *res; 272 struct display_timings *disp_timing; 273 void *addr; 274 int irq, ret; 275 276 struct fb_videomode of_mode; 277 u32 bpp; 278 dma_addr_t fb_mem_phys; 279 unsigned long fb_mem_len; 280 void *fb_mem_virt; 281 282 ret = -ENOMEM; 283 fbi = NULL; 284 285 fbi = devm_kzalloc(&pdev->dev, sizeof(struct vt8500lcd_info) 286 + sizeof(u32) * 16, GFP_KERNEL); 287 if (!fbi) 288 return -ENOMEM; 289 290 strcpy(fbi->fb.fix.id, "VT8500 LCD"); 291 292 fbi->fb.fix.type = FB_TYPE_PACKED_PIXELS; 293 fbi->fb.fix.xpanstep = 0; 294 fbi->fb.fix.ypanstep = 1; 295 fbi->fb.fix.ywrapstep = 0; 296 fbi->fb.fix.accel = FB_ACCEL_NONE; 297 298 fbi->fb.var.nonstd = 0; 299 fbi->fb.var.activate = FB_ACTIVATE_NOW; 300 fbi->fb.var.height = -1; 301 fbi->fb.var.width = -1; 302 fbi->fb.var.vmode = FB_VMODE_NONINTERLACED; 303 304 fbi->fb.fbops = &vt8500lcd_ops; 305 fbi->fb.flags = FBINFO_HWACCEL_COPYAREA 306 | FBINFO_HWACCEL_FILLRECT 307 | FBINFO_HWACCEL_YPAN 308 | FBINFO_VIRTFB 309 | FBINFO_PARTIAL_PAN_OK; 310 fbi->fb.node = -1; 311 312 addr = fbi; 313 addr = addr + sizeof(struct vt8500lcd_info); 314 fbi->fb.pseudo_palette = addr; 315 316 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 317 if (res == NULL) { 318 dev_err(&pdev->dev, "no I/O memory resource defined\n"); 319 return -ENODEV; 320 } 321 322 res = request_mem_region(res->start, resource_size(res), "vt8500lcd"); 323 if (res == NULL) { 324 dev_err(&pdev->dev, "failed to request I/O memory\n"); 325 return -EBUSY; 326 } 327 328 fbi->regbase = ioremap(res->start, resource_size(res)); 329 if (fbi->regbase == NULL) { 330 dev_err(&pdev->dev, "failed to map I/O memory\n"); 331 ret = -EBUSY; 332 goto failed_free_res; 333 } 334 335 disp_timing = of_get_display_timings(pdev->dev.of_node); 336 if (!disp_timing) { 337 ret = -EINVAL; 338 goto failed_free_io; 339 } 340 341 ret = of_get_fb_videomode(pdev->dev.of_node, &of_mode, 342 OF_USE_NATIVE_MODE); 343 if (ret) 344 goto failed_free_io; 345 346 ret = of_property_read_u32(pdev->dev.of_node, "bits-per-pixel", &bpp); 347 if (ret) 348 goto failed_free_io; 349 350 /* try allocating the framebuffer */ 351 fb_mem_len = of_mode.xres * of_mode.yres * 2 * (bpp / 8); 352 fb_mem_virt = dma_alloc_coherent(&pdev->dev, fb_mem_len, &fb_mem_phys, 353 GFP_KERNEL); 354 if (!fb_mem_virt) { 355 pr_err("%s: Failed to allocate framebuffer\n", __func__); 356 ret = -ENOMEM; 357 goto failed_free_io; 358 } 359 360 fbi->fb.fix.smem_start = fb_mem_phys; 361 fbi->fb.fix.smem_len = fb_mem_len; 362 fbi->fb.screen_buffer = fb_mem_virt; 363 364 fbi->palette_size = PAGE_ALIGN(512); 365 fbi->palette_cpu = dma_alloc_coherent(&pdev->dev, 366 fbi->palette_size, 367 &fbi->palette_phys, 368 GFP_KERNEL); 369 if (fbi->palette_cpu == NULL) { 370 dev_err(&pdev->dev, "Failed to allocate palette buffer\n"); 371 ret = -ENOMEM; 372 goto failed_free_io; 373 } 374 375 irq = platform_get_irq(pdev, 0); 376 if (irq < 0) { 377 ret = -ENODEV; 378 goto failed_free_palette; 379 } 380 381 ret = request_irq(irq, vt8500lcd_handle_irq, 0, "LCD", fbi); 382 if (ret) { 383 dev_err(&pdev->dev, "request_irq failed: %d\n", ret); 384 ret = -EBUSY; 385 goto failed_free_palette; 386 } 387 388 init_waitqueue_head(&fbi->wait); 389 390 if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) { 391 dev_err(&pdev->dev, "Failed to allocate color map\n"); 392 ret = -ENOMEM; 393 goto failed_free_irq; 394 } 395 396 fb_videomode_to_var(&fbi->fb.var, &of_mode); 397 398 fbi->fb.var.xres_virtual = of_mode.xres; 399 fbi->fb.var.yres_virtual = of_mode.yres * 2; 400 fbi->fb.var.bits_per_pixel = bpp; 401 402 ret = vt8500lcd_set_par(&fbi->fb); 403 if (ret) { 404 dev_err(&pdev->dev, "Failed to set parameters\n"); 405 goto failed_free_cmap; 406 } 407 408 writel(fbi->fb.fix.smem_start >> 22, fbi->regbase + 0x1c); 409 writel((fbi->palette_phys & 0xfffffe00) | 1, fbi->regbase + 0x18); 410 411 platform_set_drvdata(pdev, fbi); 412 413 ret = register_framebuffer(&fbi->fb); 414 if (ret < 0) { 415 dev_err(&pdev->dev, 416 "Failed to register framebuffer device: %d\n", ret); 417 goto failed_free_cmap; 418 } 419 420 /* 421 * Ok, now enable the LCD controller 422 */ 423 writel(readl(fbi->regbase) | 1, fbi->regbase); 424 425 return 0; 426 427 failed_free_cmap: 428 if (fbi->fb.cmap.len) 429 fb_dealloc_cmap(&fbi->fb.cmap); 430 failed_free_irq: 431 free_irq(irq, fbi); 432 failed_free_palette: 433 dma_free_coherent(&pdev->dev, fbi->palette_size, 434 fbi->palette_cpu, fbi->palette_phys); 435 failed_free_io: 436 iounmap(fbi->regbase); 437 failed_free_res: 438 release_mem_region(res->start, resource_size(res)); 439 return ret; 440 } 441 442 static void vt8500lcd_remove(struct platform_device *pdev) 443 { 444 struct vt8500lcd_info *fbi = platform_get_drvdata(pdev); 445 struct resource *res; 446 int irq; 447 448 unregister_framebuffer(&fbi->fb); 449 450 writel(0, fbi->regbase); 451 452 if (fbi->fb.cmap.len) 453 fb_dealloc_cmap(&fbi->fb.cmap); 454 455 irq = platform_get_irq(pdev, 0); 456 free_irq(irq, fbi); 457 458 dma_free_coherent(&pdev->dev, fbi->palette_size, 459 fbi->palette_cpu, fbi->palette_phys); 460 461 iounmap(fbi->regbase); 462 463 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 464 release_mem_region(res->start, resource_size(res)); 465 } 466 467 static const struct of_device_id via_dt_ids[] = { 468 { .compatible = "via,vt8500-fb", }, 469 {} 470 }; 471 472 static struct platform_driver vt8500lcd_driver = { 473 .probe = vt8500lcd_probe, 474 .remove_new = vt8500lcd_remove, 475 .driver = { 476 .name = "vt8500-lcd", 477 .of_match_table = of_match_ptr(via_dt_ids), 478 }, 479 }; 480 481 module_platform_driver(vt8500lcd_driver); 482 483 MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>"); 484 MODULE_DESCRIPTION("LCD controller driver for VIA VT8500"); 485 MODULE_LICENSE("GPL v2"); 486 MODULE_DEVICE_TABLE(of, via_dt_ids); 487