drivers/video/fbdev/atmel

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This source file includes following definitions.
atmel_bl_update_status
atmel_bl_get_brightness
init_backlight
exit_backlight
init_backlight
exit_backlight
init_contrast
atmel_lcdfb_power_control
compute_hozval
atmel_lcdfb_stop_nowait
atmel_lcdfb_stop
atmel_lcdfb_start
atmel_lcdfb_update_dma
atmel_lcdfb_free_video_memory
atmel_lcdfb_alloc_video_memory
atmel_lcdfb_choose_mode
atmel_lcdfb_check_var
atmel_lcdfb_reset
atmel_lcdfb_set_par
chan_to_field
atmel_lcdfb_setcolreg
atmel_lcdfb_pan_display
atmel_lcdfb_blank
atmel_lcdfb_interrupt
atmel_lcdfb_task
atmel_lcdfb_init_fbinfo
atmel_lcdfb_start_clock
atmel_lcdfb_stop_clock
atmel_lcdfb_get_of_wiring_modes
atmel_lcdfb_power_control_gpio
atmel_lcdfb_of_init
atmel_lcdfb_probe
atmel_lcdfb_remove
atmel_lcdfb_suspend
atmel_lcdfb_resume
   1 /*
   2  *  Driver for AT91 LCD Controller
   3  *
   4  *  Copyright (C) 2007 Atmel Corporation
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License.  See the file COPYING in the main directory of this archive for
   8  * more details.
   9  */
  10 
  11 #include <linux/kernel.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/dma-mapping.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/clk.h>
  16 #include <linux/fb.h>
  17 #include <linux/init.h>
  18 #include <linux/delay.h>
  19 #include <linux/backlight.h>
  20 #include <linux/gfp.h>
  21 #include <linux/gpio/consumer.h>
  22 #include <linux/module.h>
  23 #include <linux/of.h>
  24 #include <linux/of_device.h>
  25 #include <video/of_videomode.h>
  26 #include <video/of_display_timing.h>
  27 #include <linux/regulator/consumer.h>
  28 #include <video/videomode.h>
  29 
  30 #include <video/atmel_lcdc.h>
  31 
  32 struct atmel_lcdfb_config {
  33         bool have_alt_pixclock;
  34         bool have_hozval;
  35         bool have_intensity_bit;
  36 };
  37 
  38  /* LCD Controller info data structure, stored in device platform_data */
  39 struct atmel_lcdfb_info {
  40         spinlock_t              lock;
  41         struct fb_info          *info;
  42         void __iomem            *mmio;
  43         int                     irq_base;
  44         struct work_struct      task;
  45 
  46         unsigned int            smem_len;
  47         struct platform_device  *pdev;
  48         struct clk              *bus_clk;
  49         struct clk              *lcdc_clk;
  50 
  51         struct backlight_device *backlight;
  52         u8                      bl_power;
  53         u8                      saved_lcdcon;
  54 
  55         u32                     pseudo_palette[16];
  56         bool                    have_intensity_bit;
  57 
  58         struct atmel_lcdfb_pdata pdata;
  59 
  60         struct atmel_lcdfb_config *config;
  61         struct regulator        *reg_lcd;
  62 };
  63 
  64 struct atmel_lcdfb_power_ctrl_gpio {
  65         struct gpio_desc *gpiod;
  66 
  67         struct list_head list;
  68 };
  69 
  70 #define lcdc_readl(sinfo, reg)          __raw_readl((sinfo)->mmio+(reg))
  71 #define lcdc_writel(sinfo, reg, val)    __raw_writel((val), (sinfo)->mmio+(reg))
  72 
  73 /* configurable parameters */
  74 #define ATMEL_LCDC_CVAL_DEFAULT         0xc8
  75 #define ATMEL_LCDC_DMA_BURST_LEN        8       /* words */
  76 #define ATMEL_LCDC_FIFO_SIZE            512     /* words */
  77 
  78 static struct atmel_lcdfb_config at91sam9261_config = {
  79         .have_hozval            = true,
  80         .have_intensity_bit     = true,
  81 };
  82 
  83 static struct atmel_lcdfb_config at91sam9263_config = {
  84         .have_intensity_bit     = true,
  85 };
  86 
  87 static struct atmel_lcdfb_config at91sam9g10_config = {
  88         .have_hozval            = true,
  89 };
  90 
  91 static struct atmel_lcdfb_config at91sam9g45_config = {
  92         .have_alt_pixclock      = true,
  93 };
  94 
  95 static struct atmel_lcdfb_config at91sam9g45es_config = {
  96 };
  97 
  98 static struct atmel_lcdfb_config at91sam9rl_config = {
  99         .have_intensity_bit     = true,
 100 };
 101 
 102 static u32 contrast_ctr = ATMEL_LCDC_PS_DIV8
 103                 | ATMEL_LCDC_POL_POSITIVE
 104                 | ATMEL_LCDC_ENA_PWMENABLE;
 105 
 106 #ifdef CONFIG_BACKLIGHT_ATMEL_LCDC
 107 
 108 /* some bl->props field just changed */
 109 static int atmel_bl_update_status(struct backlight_device *bl)
 110 {
 111         struct atmel_lcdfb_info *sinfo = bl_get_data(bl);
 112         int                     power = sinfo->bl_power;
 113         int                     brightness = bl->props.brightness;
 114 
 115         /* REVISIT there may be a meaningful difference between
 116          * fb_blank and power ... there seem to be some cases
 117          * this doesn't handle correctly.
 118          */
 119         if (bl->props.fb_blank != sinfo->bl_power)
 120                 power = bl->props.fb_blank;
 121         else if (bl->props.power != sinfo->bl_power)
 122                 power = bl->props.power;
 123 
 124         if (brightness < 0 && power == FB_BLANK_UNBLANK)
 125                 brightness = lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
 126         else if (power != FB_BLANK_UNBLANK)
 127                 brightness = 0;
 128 
 129         lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, brightness);
 130         if (contrast_ctr & ATMEL_LCDC_POL_POSITIVE)
 131                 lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR,
 132                         brightness ? contrast_ctr : 0);
 133         else
 134                 lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, contrast_ctr);
 135 
 136         bl->props.fb_blank = bl->props.power = sinfo->bl_power = power;
 137 
 138         return 0;
 139 }
 140 
 141 static int atmel_bl_get_brightness(struct backlight_device *bl)
 142 {
 143         struct atmel_lcdfb_info *sinfo = bl_get_data(bl);
 144 
 145         return lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
 146 }
 147 
 148 static const struct backlight_ops atmel_lcdc_bl_ops = {
 149         .update_status = atmel_bl_update_status,
 150         .get_brightness = atmel_bl_get_brightness,
 151 };
 152 
 153 static void init_backlight(struct atmel_lcdfb_info *sinfo)
 154 {
 155         struct backlight_properties props;
 156         struct backlight_device *bl;
 157 
 158         sinfo->bl_power = FB_BLANK_UNBLANK;
 159 
 160         if (sinfo->backlight)
 161                 return;
 162 
 163         memset(&props, 0, sizeof(struct backlight_properties));
 164         props.type = BACKLIGHT_RAW;
 165         props.max_brightness = 0xff;
 166         bl = backlight_device_register("backlight", &sinfo->pdev->dev, sinfo,
 167                                        &atmel_lcdc_bl_ops, &props);
 168         if (IS_ERR(bl)) {
 169                 dev_err(&sinfo->pdev->dev, "error %ld on backlight register\n",
 170                                 PTR_ERR(bl));
 171                 return;
 172         }
 173         sinfo->backlight = bl;
 174 
 175         bl->props.power = FB_BLANK_UNBLANK;
 176         bl->props.fb_blank = FB_BLANK_UNBLANK;
 177         bl->props.brightness = atmel_bl_get_brightness(bl);
 178 }
 179 
 180 static void exit_backlight(struct atmel_lcdfb_info *sinfo)
 181 {
 182         if (!sinfo->backlight)
 183                 return;
 184 
 185         if (sinfo->backlight->ops) {
 186                 sinfo->backlight->props.power = FB_BLANK_POWERDOWN;
 187                 sinfo->backlight->ops->update_status(sinfo->backlight);
 188         }
 189         backlight_device_unregister(sinfo->backlight);
 190 }
 191 
 192 #else
 193 
 194 static void init_backlight(struct atmel_lcdfb_info *sinfo)
 195 {
 196         dev_warn(&sinfo->pdev->dev, "backlight control is not available\n");
 197 }
 198 
 199 static void exit_backlight(struct atmel_lcdfb_info *sinfo)
 200 {
 201 }
 202 
 203 #endif
 204 
 205 static void init_contrast(struct atmel_lcdfb_info *sinfo)
 206 {
 207         struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
 208 
 209         /* contrast pwm can be 'inverted' */
 210         if (pdata->lcdcon_pol_negative)
 211                 contrast_ctr &= ~(ATMEL_LCDC_POL_POSITIVE);
 212 
 213         /* have some default contrast/backlight settings */
 214         lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, contrast_ctr);
 215         lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, ATMEL_LCDC_CVAL_DEFAULT);
 216 
 217         if (pdata->lcdcon_is_backlight)
 218                 init_backlight(sinfo);
 219 }
 220 
 221 static inline void atmel_lcdfb_power_control(struct atmel_lcdfb_info *sinfo, int on)
 222 {
 223         int ret;
 224         struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
 225 
 226         if (pdata->atmel_lcdfb_power_control)
 227                 pdata->atmel_lcdfb_power_control(pdata, on);
 228         else if (sinfo->reg_lcd) {
 229                 if (on) {
 230                         ret = regulator_enable(sinfo->reg_lcd);
 231                         if (ret)
 232                                 dev_err(&sinfo->pdev->dev,
 233                                         "lcd regulator enable failed:   %d\n", ret);
 234                 } else {
 235                         ret = regulator_disable(sinfo->reg_lcd);
 236                         if (ret)
 237                                 dev_err(&sinfo->pdev->dev,
 238                                         "lcd regulator disable failed: %d\n", ret);
 239                 }
 240         }
 241 }
 242 
 243 static const struct fb_fix_screeninfo atmel_lcdfb_fix __initconst = {
 244         .type           = FB_TYPE_PACKED_PIXELS,
 245         .visual         = FB_VISUAL_TRUECOLOR,
 246         .xpanstep       = 0,
 247         .ypanstep       = 1,
 248         .ywrapstep      = 0,
 249         .accel          = FB_ACCEL_NONE,
 250 };
 251 
 252 static unsigned long compute_hozval(struct atmel_lcdfb_info *sinfo,
 253                                                         unsigned long xres)
 254 {
 255         unsigned long lcdcon2;
 256         unsigned long value;
 257 
 258         if (!sinfo->config->have_hozval)
 259                 return xres;
 260 
 261         lcdcon2 = lcdc_readl(sinfo, ATMEL_LCDC_LCDCON2);
 262         value = xres;
 263         if ((lcdcon2 & ATMEL_LCDC_DISTYPE) != ATMEL_LCDC_DISTYPE_TFT) {
 264                 /* STN display */
 265                 if ((lcdcon2 & ATMEL_LCDC_DISTYPE) == ATMEL_LCDC_DISTYPE_STNCOLOR) {
 266                         value *= 3;
 267                 }
 268                 if ( (lcdcon2 & ATMEL_LCDC_IFWIDTH) == ATMEL_LCDC_IFWIDTH_4
 269                    || ( (lcdcon2 & ATMEL_LCDC_IFWIDTH) == ATMEL_LCDC_IFWIDTH_8
 270                       && (lcdcon2 & ATMEL_LCDC_SCANMOD) == ATMEL_LCDC_SCANMOD_DUAL ))
 271                         value = DIV_ROUND_UP(value, 4);
 272                 else
 273                         value = DIV_ROUND_UP(value, 8);
 274         }
 275 
 276         return value;
 277 }
 278 
 279 static void atmel_lcdfb_stop_nowait(struct atmel_lcdfb_info *sinfo)
 280 {
 281         struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
 282 
 283         /* Turn off the LCD controller and the DMA controller */
 284         lcdc_writel(sinfo, ATMEL_LCDC_PWRCON,
 285                         pdata->guard_time << ATMEL_LCDC_GUARDT_OFFSET);
 286 
 287         /* Wait for the LCDC core to become idle */
 288         while (lcdc_readl(sinfo, ATMEL_LCDC_PWRCON) & ATMEL_LCDC_BUSY)
 289                 msleep(10);
 290 
 291         lcdc_writel(sinfo, ATMEL_LCDC_DMACON, 0);
 292 }
 293 
 294 static void atmel_lcdfb_stop(struct atmel_lcdfb_info *sinfo)
 295 {
 296         atmel_lcdfb_stop_nowait(sinfo);
 297 
 298         /* Wait for DMA engine to become idle... */
 299         while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY)
 300                 msleep(10);
 301 }
 302 
 303 static void atmel_lcdfb_start(struct atmel_lcdfb_info *sinfo)
 304 {
 305         struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
 306 
 307         lcdc_writel(sinfo, ATMEL_LCDC_DMACON, pdata->default_dmacon);
 308         lcdc_writel(sinfo, ATMEL_LCDC_PWRCON,
 309                 (pdata->guard_time << ATMEL_LCDC_GUARDT_OFFSET)
 310                 | ATMEL_LCDC_PWR);
 311 }
 312 
 313 static void atmel_lcdfb_update_dma(struct fb_info *info,
 314                                struct fb_var_screeninfo *var)
 315 {
 316         struct atmel_lcdfb_info *sinfo = info->par;
 317         struct fb_fix_screeninfo *fix = &info->fix;
 318         unsigned long dma_addr;
 319 
 320         dma_addr = (fix->smem_start + var->yoffset * fix->line_length
 321                     + var->xoffset * info->var.bits_per_pixel / 8);
 322 
 323         dma_addr &= ~3UL;
 324 
 325         /* Set framebuffer DMA base address and pixel offset */
 326         lcdc_writel(sinfo, ATMEL_LCDC_DMABADDR1, dma_addr);
 327 }
 328 
 329 static inline void atmel_lcdfb_free_video_memory(struct atmel_lcdfb_info *sinfo)
 330 {
 331         struct fb_info *info = sinfo->info;
 332 
 333         dma_free_wc(info->device, info->fix.smem_len, info->screen_base,
 334                     info->fix.smem_start);
 335 }
 336 
 337 /**
 338  *      atmel_lcdfb_alloc_video_memory - Allocate framebuffer memory
 339  *      @sinfo: the frame buffer to allocate memory for
 340  *      
 341  *      This function is called only from the atmel_lcdfb_probe()
 342  *      so no locking by fb_info->mm_lock around smem_len setting is needed.
 343  */
 344 static int atmel_lcdfb_alloc_video_memory(struct atmel_lcdfb_info *sinfo)
 345 {
 346         struct fb_info *info = sinfo->info;
 347         struct fb_var_screeninfo *var = &info->var;
 348         unsigned int smem_len;
 349 
 350         smem_len = (var->xres_virtual * var->yres_virtual
 351                     * ((var->bits_per_pixel + 7) / 8));
 352         info->fix.smem_len = max(smem_len, sinfo->smem_len);
 353 
 354         info->screen_base = dma_alloc_wc(info->device, info->fix.smem_len,
 355                                          (dma_addr_t *)&info->fix.smem_start,
 356                                          GFP_KERNEL);
 357 
 358         if (!info->screen_base) {
 359                 return -ENOMEM;
 360         }
 361 
 362         memset(info->screen_base, 0, info->fix.smem_len);
 363 
 364         return 0;
 365 }
 366 
 367 static const struct fb_videomode *atmel_lcdfb_choose_mode(struct fb_var_screeninfo *var,
 368                                                      struct fb_info *info)
 369 {
 370         struct fb_videomode varfbmode;
 371         const struct fb_videomode *fbmode = NULL;
 372 
 373         fb_var_to_videomode(&varfbmode, var);
 374         fbmode = fb_find_nearest_mode(&varfbmode, &info->modelist);
 375         if (fbmode)
 376                 fb_videomode_to_var(var, fbmode);
 377         return fbmode;
 378 }
 379 
 380 
 381 /**
 382  *      atmel_lcdfb_check_var - Validates a var passed in.
 383  *      @var: frame buffer variable screen structure
 384  *      @info: frame buffer structure that represents a single frame buffer
 385  *
 386  *      Checks to see if the hardware supports the state requested by
 387  *      var passed in. This function does not alter the hardware
 388  *      state!!!  This means the data stored in struct fb_info and
 389  *      struct atmel_lcdfb_info do not change. This includes the var
 390  *      inside of struct fb_info.  Do NOT change these. This function
 391  *      can be called on its own if we intent to only test a mode and
 392  *      not actually set it. The stuff in modedb.c is a example of
 393  *      this. If the var passed in is slightly off by what the
 394  *      hardware can support then we alter the var PASSED in to what
 395  *      we can do. If the hardware doesn't support mode change a
 396  *      -EINVAL will be returned by the upper layers. You don't need
 397  *      to implement this function then. If you hardware doesn't
 398  *      support changing the resolution then this function is not
 399  *      needed. In this case the driver would just provide a var that
 400  *      represents the static state the screen is in.
 401  *
 402  *      Returns negative errno on error, or zero on success.
 403  */
 404 static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var,
 405                              struct fb_info *info)
 406 {
 407         struct device *dev = info->device;
 408         struct atmel_lcdfb_info *sinfo = info->par;
 409         struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
 410         unsigned long clk_value_khz;
 411 
 412         clk_value_khz = clk_get_rate(sinfo->lcdc_clk) / 1000;
 413 
 414         dev_dbg(dev, "%s:\n", __func__);
 415 
 416         if (!(var->pixclock && var->bits_per_pixel)) {
 417                 /* choose a suitable mode if possible */
 418                 if (!atmel_lcdfb_choose_mode(var, info)) {
 419                         dev_err(dev, "needed value not specified\n");
 420                         return -EINVAL;
 421                 }
 422         }
 423 
 424         dev_dbg(dev, "  resolution: %ux%u\n", var->xres, var->yres);
 425         dev_dbg(dev, "  pixclk:     %lu KHz\n", PICOS2KHZ(var->pixclock));
 426         dev_dbg(dev, "  bpp:        %u\n", var->bits_per_pixel);
 427         dev_dbg(dev, "  clk:        %lu KHz\n", clk_value_khz);
 428 
 429         if (PICOS2KHZ(var->pixclock) > clk_value_khz) {
 430                 dev_err(dev, "%lu KHz pixel clock is too fast\n", PICOS2KHZ(var->pixclock));
 431                 return -EINVAL;
 432         }
 433 
 434         /* Do not allow to have real resoulution larger than virtual */
 435         if (var->xres > var->xres_virtual)
 436                 var->xres_virtual = var->xres;
 437 
 438         if (var->yres > var->yres_virtual)
 439                 var->yres_virtual = var->yres;
 440 
 441         /* Force same alignment for each line */
 442         var->xres = (var->xres + 3) & ~3UL;
 443         var->xres_virtual = (var->xres_virtual + 3) & ~3UL;
 444 
 445         var->red.msb_right = var->green.msb_right = var->blue.msb_right = 0;
 446         var->transp.msb_right = 0;
 447         var->transp.offset = var->transp.length = 0;
 448         var->xoffset = var->yoffset = 0;
 449 
 450         if (info->fix.smem_len) {
 451                 unsigned int smem_len = (var->xres_virtual * var->yres_virtual
 452                                          * ((var->bits_per_pixel + 7) / 8));
 453                 if (smem_len > info->fix.smem_len) {
 454                         dev_err(dev, "Frame buffer is too small (%u) for screen size (need at least %u)\n",
 455                                 info->fix.smem_len, smem_len);
 456                         return -EINVAL;
 457                 }
 458         }
 459 
 460         /* Saturate vertical and horizontal timings at maximum values */
 461         var->vsync_len = min_t(u32, var->vsync_len,
 462                         (ATMEL_LCDC_VPW >> ATMEL_LCDC_VPW_OFFSET) + 1);
 463         var->upper_margin = min_t(u32, var->upper_margin,
 464                         ATMEL_LCDC_VBP >> ATMEL_LCDC_VBP_OFFSET);
 465         var->lower_margin = min_t(u32, var->lower_margin,
 466                         ATMEL_LCDC_VFP);
 467         var->right_margin = min_t(u32, var->right_margin,
 468                         (ATMEL_LCDC_HFP >> ATMEL_LCDC_HFP_OFFSET) + 1);
 469         var->hsync_len = min_t(u32, var->hsync_len,
 470                         (ATMEL_LCDC_HPW >> ATMEL_LCDC_HPW_OFFSET) + 1);
 471         var->left_margin = min_t(u32, var->left_margin,
 472                         ATMEL_LCDC_HBP + 1);
 473 
 474         /* Some parameters can't be zero */
 475         var->vsync_len = max_t(u32, var->vsync_len, 1);
 476         var->right_margin = max_t(u32, var->right_margin, 1);
 477         var->hsync_len = max_t(u32, var->hsync_len, 1);
 478         var->left_margin = max_t(u32, var->left_margin, 1);
 479 
 480         switch (var->bits_per_pixel) {
 481         case 1:
 482         case 2:
 483         case 4:
 484         case 8:
 485                 var->red.offset = var->green.offset = var->blue.offset = 0;
 486                 var->red.length = var->green.length = var->blue.length
 487                         = var->bits_per_pixel;
 488                 break;
 489         case 16:
 490                 /* Older SOCs use IBGR:555 rather than BGR:565. */
 491                 if (sinfo->config->have_intensity_bit)
 492                         var->green.length = 5;
 493                 else
 494                         var->green.length = 6;
 495 
 496                 if (pdata->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
 497                         /* RGB:5X5 mode */
 498                         var->red.offset = var->green.length + 5;
 499                         var->blue.offset = 0;
 500                 } else {
 501                         /* BGR:5X5 mode */
 502                         var->red.offset = 0;
 503                         var->blue.offset = var->green.length + 5;
 504                 }
 505                 var->green.offset = 5;
 506                 var->red.length = var->blue.length = 5;
 507                 break;
 508         case 32:
 509                 var->transp.offset = 24;
 510                 var->transp.length = 8;
 511                 /* fall through */
 512         case 24:
 513                 if (pdata->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
 514                         /* RGB:888 mode */
 515                         var->red.offset = 16;
 516                         var->blue.offset = 0;
 517                 } else {
 518                         /* BGR:888 mode */
 519                         var->red.offset = 0;
 520                         var->blue.offset = 16;
 521                 }
 522                 var->green.offset = 8;
 523                 var->red.length = var->green.length = var->blue.length = 8;
 524                 break;
 525         default:
 526                 dev_err(dev, "color depth %d not supported\n",
 527                                         var->bits_per_pixel);
 528                 return -EINVAL;
 529         }
 530 
 531         return 0;
 532 }
 533 
 534 /*
 535  * LCD reset sequence
 536  */
 537 static void atmel_lcdfb_reset(struct atmel_lcdfb_info *sinfo)
 538 {
 539         might_sleep();
 540 
 541         atmel_lcdfb_stop(sinfo);
 542         atmel_lcdfb_start(sinfo);
 543 }
 544 
 545 /**
 546  *      atmel_lcdfb_set_par - Alters the hardware state.
 547  *      @info: frame buffer structure that represents a single frame buffer
 548  *
 549  *      Using the fb_var_screeninfo in fb_info we set the resolution
 550  *      of the this particular framebuffer. This function alters the
 551  *      par AND the fb_fix_screeninfo stored in fb_info. It doesn't
 552  *      not alter var in fb_info since we are using that data. This
 553  *      means we depend on the data in var inside fb_info to be
 554  *      supported by the hardware.  atmel_lcdfb_check_var is always called
 555  *      before atmel_lcdfb_set_par to ensure this.  Again if you can't
 556  *      change the resolution you don't need this function.
 557  *
 558  */
 559 static int atmel_lcdfb_set_par(struct fb_info *info)
 560 {
 561         struct atmel_lcdfb_info *sinfo = info->par;
 562         struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
 563         unsigned long hozval_linesz;
 564         unsigned long value;
 565         unsigned long clk_value_khz;
 566         unsigned long bits_per_line;
 567         unsigned long pix_factor = 2;
 568 
 569         might_sleep();
 570 
 571         dev_dbg(info->device, "%s:\n", __func__);
 572         dev_dbg(info->device, "  * resolution: %ux%u (%ux%u virtual)\n",
 573                  info->var.xres, info->var.yres,
 574                  info->var.xres_virtual, info->var.yres_virtual);
 575 
 576         atmel_lcdfb_stop_nowait(sinfo);
 577 
 578         if (info->var.bits_per_pixel == 1)
 579                 info->fix.visual = FB_VISUAL_MONO01;
 580         else if (info->var.bits_per_pixel <= 8)
 581                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
 582         else
 583                 info->fix.visual = FB_VISUAL_TRUECOLOR;
 584 
 585         bits_per_line = info->var.xres_virtual * info->var.bits_per_pixel;
 586         info->fix.line_length = DIV_ROUND_UP(bits_per_line, 8);
 587 
 588         /* Re-initialize the DMA engine... */
 589         dev_dbg(info->device, "  * update DMA engine\n");
 590         atmel_lcdfb_update_dma(info, &info->var);
 591 
 592         /* ...set frame size and burst length = 8 words (?) */
 593         value = (info->var.yres * info->var.xres * info->var.bits_per_pixel) / 32;
 594         value |= ((ATMEL_LCDC_DMA_BURST_LEN - 1) << ATMEL_LCDC_BLENGTH_OFFSET);
 595         lcdc_writel(sinfo, ATMEL_LCDC_DMAFRMCFG, value);
 596 
 597         /* Now, the LCDC core... */
 598 
 599         /* Set pixel clock */
 600         if (sinfo->config->have_alt_pixclock)
 601                 pix_factor = 1;
 602 
 603         clk_value_khz = clk_get_rate(sinfo->lcdc_clk) / 1000;
 604 
 605         value = DIV_ROUND_UP(clk_value_khz, PICOS2KHZ(info->var.pixclock));
 606 
 607         if (value < pix_factor) {
 608                 dev_notice(info->device, "Bypassing pixel clock divider\n");
 609                 lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1, ATMEL_LCDC_BYPASS);
 610         } else {
 611                 value = (value / pix_factor) - 1;
 612                 dev_dbg(info->device, "  * programming CLKVAL = 0x%08lx\n",
 613                                 value);
 614                 lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1,
 615                                 value << ATMEL_LCDC_CLKVAL_OFFSET);
 616                 info->var.pixclock =
 617                         KHZ2PICOS(clk_value_khz / (pix_factor * (value + 1)));
 618                 dev_dbg(info->device, "  updated pixclk:     %lu KHz\n",
 619                                         PICOS2KHZ(info->var.pixclock));
 620         }
 621 
 622 
 623         /* Initialize control register 2 */
 624         value = pdata->default_lcdcon2;
 625 
 626         if (!(info->var.sync & FB_SYNC_HOR_HIGH_ACT))
 627                 value |= ATMEL_LCDC_INVLINE_INVERTED;
 628         if (!(info->var.sync & FB_SYNC_VERT_HIGH_ACT))
 629                 value |= ATMEL_LCDC_INVFRAME_INVERTED;
 630 
 631         switch (info->var.bits_per_pixel) {
 632                 case 1: value |= ATMEL_LCDC_PIXELSIZE_1; break;
 633                 case 2: value |= ATMEL_LCDC_PIXELSIZE_2; break;
 634                 case 4: value |= ATMEL_LCDC_PIXELSIZE_4; break;
 635                 case 8: value |= ATMEL_LCDC_PIXELSIZE_8; break;
 636                 case 15: /* fall through */
 637                 case 16: value |= ATMEL_LCDC_PIXELSIZE_16; break;
 638                 case 24: value |= ATMEL_LCDC_PIXELSIZE_24; break;
 639                 case 32: value |= ATMEL_LCDC_PIXELSIZE_32; break;
 640                 default: BUG(); break;
 641         }
 642         dev_dbg(info->device, "  * LCDCON2 = %08lx\n", value);
 643         lcdc_writel(sinfo, ATMEL_LCDC_LCDCON2, value);
 644 
 645         /* Vertical timing */
 646         value = (info->var.vsync_len - 1) << ATMEL_LCDC_VPW_OFFSET;
 647         value |= info->var.upper_margin << ATMEL_LCDC_VBP_OFFSET;
 648         value |= info->var.lower_margin;
 649         dev_dbg(info->device, "  * LCDTIM1 = %08lx\n", value);
 650         lcdc_writel(sinfo, ATMEL_LCDC_TIM1, value);
 651 
 652         /* Horizontal timing */
 653         value = (info->var.right_margin - 1) << ATMEL_LCDC_HFP_OFFSET;
 654         value |= (info->var.hsync_len - 1) << ATMEL_LCDC_HPW_OFFSET;
 655         value |= (info->var.left_margin - 1);
 656         dev_dbg(info->device, "  * LCDTIM2 = %08lx\n", value);
 657         lcdc_writel(sinfo, ATMEL_LCDC_TIM2, value);
 658 
 659         /* Horizontal value (aka line size) */
 660         hozval_linesz = compute_hozval(sinfo, info->var.xres);
 661 
 662         /* Display size */
 663         value = (hozval_linesz - 1) << ATMEL_LCDC_HOZVAL_OFFSET;
 664         value |= info->var.yres - 1;
 665         dev_dbg(info->device, "  * LCDFRMCFG = %08lx\n", value);
 666         lcdc_writel(sinfo, ATMEL_LCDC_LCDFRMCFG, value);
 667 
 668         /* FIFO Threshold: Use formula from data sheet */
 669         value = ATMEL_LCDC_FIFO_SIZE - (2 * ATMEL_LCDC_DMA_BURST_LEN + 3);
 670         lcdc_writel(sinfo, ATMEL_LCDC_FIFO, value);
 671 
 672         /* Toggle LCD_MODE every frame */
 673         lcdc_writel(sinfo, ATMEL_LCDC_MVAL, 0);
 674 
 675         /* Disable all interrupts */
 676         lcdc_writel(sinfo, ATMEL_LCDC_IDR, ~0U);
 677         /* Enable FIFO & DMA errors */
 678         lcdc_writel(sinfo, ATMEL_LCDC_IER, ATMEL_LCDC_UFLWI | ATMEL_LCDC_OWRI | ATMEL_LCDC_MERI);
 679 
 680         /* ...wait for DMA engine to become idle... */
 681         while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY)
 682                 msleep(10);
 683 
 684         atmel_lcdfb_start(sinfo);
 685 
 686         dev_dbg(info->device, "  * DONE\n");
 687 
 688         return 0;
 689 }
 690 
 691 static inline unsigned int chan_to_field(unsigned int chan, const struct fb_bitfield *bf)
 692 {
 693         chan &= 0xffff;
 694         chan >>= 16 - bf->length;
 695         return chan << bf->offset;
 696 }
 697 
 698 /**
 699  *      atmel_lcdfb_setcolreg - Optional function. Sets a color register.
 700  *      @regno: Which register in the CLUT we are programming
 701  *      @red: The red value which can be up to 16 bits wide
 702  *      @green: The green value which can be up to 16 bits wide
 703  *      @blue:  The blue value which can be up to 16 bits wide.
 704  *      @transp: If supported the alpha value which can be up to 16 bits wide.
 705  *      @info: frame buffer info structure
 706  *
 707  *      Set a single color register. The values supplied have a 16 bit
 708  *      magnitude which needs to be scaled in this function for the hardware.
 709  *      Things to take into consideration are how many color registers, if
 710  *      any, are supported with the current color visual. With truecolor mode
 711  *      no color palettes are supported. Here a pseudo palette is created
 712  *      which we store the value in pseudo_palette in struct fb_info. For
 713  *      pseudocolor mode we have a limited color palette. To deal with this
 714  *      we can program what color is displayed for a particular pixel value.
 715  *      DirectColor is similar in that we can program each color field. If
 716  *      we have a static colormap we don't need to implement this function.
 717  *
 718  *      Returns negative errno on error, or zero on success. In an
 719  *      ideal world, this would have been the case, but as it turns
 720  *      out, the other drivers return 1 on failure, so that's what
 721  *      we're going to do.
 722  */
 723 static int atmel_lcdfb_setcolreg(unsigned int regno, unsigned int red,
 724                              unsigned int green, unsigned int blue,
 725                              unsigned int transp, struct fb_info *info)
 726 {
 727         struct atmel_lcdfb_info *sinfo = info->par;
 728         struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
 729         unsigned int val;
 730         u32 *pal;
 731         int ret = 1;
 732 
 733         if (info->var.grayscale)
 734                 red = green = blue = (19595 * red + 38470 * green
 735                                       + 7471 * blue) >> 16;
 736 
 737         switch (info->fix.visual) {
 738         case FB_VISUAL_TRUECOLOR:
 739                 if (regno < 16) {
 740                         pal = info->pseudo_palette;
 741 
 742                         val  = chan_to_field(red, &info->var.red);
 743                         val |= chan_to_field(green, &info->var.green);
 744                         val |= chan_to_field(blue, &info->var.blue);
 745 
 746                         pal[regno] = val;
 747                         ret = 0;
 748                 }
 749                 break;
 750 
 751         case FB_VISUAL_PSEUDOCOLOR:
 752                 if (regno < 256) {
 753                         if (sinfo->config->have_intensity_bit) {
 754                                 /* old style I+BGR:555 */
 755                                 val  = ((red   >> 11) & 0x001f);
 756                                 val |= ((green >>  6) & 0x03e0);
 757                                 val |= ((blue  >>  1) & 0x7c00);
 758 
 759                                 /*
 760                                  * TODO: intensity bit. Maybe something like
 761                                  *   ~(red[10] ^ green[10] ^ blue[10]) & 1
 762                                  */
 763                         } else {
 764                                 /* new style BGR:565 / RGB:565 */
 765                                 if (pdata->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
 766                                         val  = ((blue >> 11) & 0x001f);
 767                                         val |= ((red  >>  0) & 0xf800);
 768                                 } else {
 769                                         val  = ((red  >> 11) & 0x001f);
 770                                         val |= ((blue >>  0) & 0xf800);
 771                                 }
 772 
 773                                 val |= ((green >>  5) & 0x07e0);
 774                         }
 775 
 776                         lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);
 777                         ret = 0;
 778                 }
 779                 break;
 780 
 781         case FB_VISUAL_MONO01:
 782                 if (regno < 2) {
 783                         val = (regno == 0) ? 0x00 : 0x1F;
 784                         lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);
 785                         ret = 0;
 786                 }
 787                 break;
 788 
 789         }
 790 
 791         return ret;
 792 }
 793 
 794 static int atmel_lcdfb_pan_display(struct fb_var_screeninfo *var,
 795                                struct fb_info *info)
 796 {
 797         dev_dbg(info->device, "%s\n", __func__);
 798 
 799         atmel_lcdfb_update_dma(info, var);
 800 
 801         return 0;
 802 }
 803 
 804 static int atmel_lcdfb_blank(int blank_mode, struct fb_info *info)
 805 {
 806         struct atmel_lcdfb_info *sinfo = info->par;
 807 
 808         switch (blank_mode) {
 809         case FB_BLANK_UNBLANK:
 810         case FB_BLANK_NORMAL:
 811                 atmel_lcdfb_start(sinfo);
 812                 break;
 813         case FB_BLANK_VSYNC_SUSPEND:
 814         case FB_BLANK_HSYNC_SUSPEND:
 815                 break;
 816         case FB_BLANK_POWERDOWN:
 817                 atmel_lcdfb_stop(sinfo);
 818                 break;
 819         default:
 820                 return -EINVAL;
 821         }
 822 
 823         /* let fbcon do a soft blank for us */
 824         return ((blank_mode == FB_BLANK_NORMAL) ? 1 : 0);
 825 }
 826 
 827 static struct fb_ops atmel_lcdfb_ops = {
 828         .owner          = THIS_MODULE,
 829         .fb_check_var   = atmel_lcdfb_check_var,
 830         .fb_set_par     = atmel_lcdfb_set_par,
 831         .fb_setcolreg   = atmel_lcdfb_setcolreg,
 832         .fb_blank       = atmel_lcdfb_blank,
 833         .fb_pan_display = atmel_lcdfb_pan_display,
 834         .fb_fillrect    = cfb_fillrect,
 835         .fb_copyarea    = cfb_copyarea,
 836         .fb_imageblit   = cfb_imageblit,
 837 };
 838 
 839 static irqreturn_t atmel_lcdfb_interrupt(int irq, void *dev_id)
 840 {
 841         struct fb_info *info = dev_id;
 842         struct atmel_lcdfb_info *sinfo = info->par;
 843         u32 status;
 844 
 845         status = lcdc_readl(sinfo, ATMEL_LCDC_ISR);
 846         if (status & ATMEL_LCDC_UFLWI) {
 847                 dev_warn(info->device, "FIFO underflow %#x\n", status);
 848                 /* reset DMA and FIFO to avoid screen shifting */
 849                 schedule_work(&sinfo->task);
 850         }
 851         lcdc_writel(sinfo, ATMEL_LCDC_ICR, status);
 852         return IRQ_HANDLED;
 853 }
 854 
 855 /*
 856  * LCD controller task (to reset the LCD)
 857  */
 858 static void atmel_lcdfb_task(struct work_struct *work)
 859 {
 860         struct atmel_lcdfb_info *sinfo =
 861                 container_of(work, struct atmel_lcdfb_info, task);
 862 
 863         atmel_lcdfb_reset(sinfo);
 864 }
 865 
 866 static int __init atmel_lcdfb_init_fbinfo(struct atmel_lcdfb_info *sinfo)
 867 {
 868         struct fb_info *info = sinfo->info;
 869         int ret = 0;
 870 
 871         info->var.activate |= FB_ACTIVATE_FORCE | FB_ACTIVATE_NOW;
 872 
 873         dev_info(info->device,
 874                "%luKiB frame buffer at %08lx (mapped at %p)\n",
 875                (unsigned long)info->fix.smem_len / 1024,
 876                (unsigned long)info->fix.smem_start,
 877                info->screen_base);
 878 
 879         /* Allocate colormap */
 880         ret = fb_alloc_cmap(&info->cmap, 256, 0);
 881         if (ret < 0)
 882                 dev_err(info->device, "Alloc color map failed\n");
 883 
 884         return ret;
 885 }
 886 
 887 static void atmel_lcdfb_start_clock(struct atmel_lcdfb_info *sinfo)
 888 {
 889         clk_prepare_enable(sinfo->bus_clk);
 890         clk_prepare_enable(sinfo->lcdc_clk);
 891 }
 892 
 893 static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
 894 {
 895         clk_disable_unprepare(sinfo->bus_clk);
 896         clk_disable_unprepare(sinfo->lcdc_clk);
 897 }
 898 
 899 static const struct of_device_id atmel_lcdfb_dt_ids[] = {
 900         { .compatible = "atmel,at91sam9261-lcdc" , .data = &at91sam9261_config, },
 901         { .compatible = "atmel,at91sam9263-lcdc" , .data = &at91sam9263_config, },
 902         { .compatible = "atmel,at91sam9g10-lcdc" , .data = &at91sam9g10_config, },
 903         { .compatible = "atmel,at91sam9g45-lcdc" , .data = &at91sam9g45_config, },
 904         { .compatible = "atmel,at91sam9g45es-lcdc" , .data = &at91sam9g45es_config, },
 905         { .compatible = "atmel,at91sam9rl-lcdc" , .data = &at91sam9rl_config, },
 906         { /* sentinel */ }
 907 };
 908 
 909 MODULE_DEVICE_TABLE(of, atmel_lcdfb_dt_ids);
 910 
 911 static const char *atmel_lcdfb_wiring_modes[] = {
 912         [ATMEL_LCDC_WIRING_BGR] = "BRG",
 913         [ATMEL_LCDC_WIRING_RGB] = "RGB",
 914 };
 915 
 916 static int atmel_lcdfb_get_of_wiring_modes(struct device_node *np)
 917 {
 918         const char *mode;
 919         int err, i;
 920 
 921         err = of_property_read_string(np, "atmel,lcd-wiring-mode", &mode);
 922         if (err < 0)
 923                 return ATMEL_LCDC_WIRING_BGR;
 924 
 925         for (i = 0; i < ARRAY_SIZE(atmel_lcdfb_wiring_modes); i++)
 926                 if (!strcasecmp(mode, atmel_lcdfb_wiring_modes[i]))
 927                         return i;
 928 
 929         return -ENODEV;
 930 }
 931 
 932 static void atmel_lcdfb_power_control_gpio(struct atmel_lcdfb_pdata *pdata, int on)
 933 {
 934         struct atmel_lcdfb_power_ctrl_gpio *og;
 935 
 936         list_for_each_entry(og, &pdata->pwr_gpios, list)
 937                 gpiod_set_value(og->gpiod, on);
 938 }
 939 
 940 static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
 941 {
 942         struct fb_info *info = sinfo->info;
 943         struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
 944         struct fb_var_screeninfo *var = &info->var;
 945         struct device *dev = &sinfo->pdev->dev;
 946         struct device_node *np =dev->of_node;
 947         struct device_node *display_np;
 948         struct atmel_lcdfb_power_ctrl_gpio *og;
 949         bool is_gpio_power = false;
 950         struct fb_videomode fb_vm;
 951         struct gpio_desc *gpiod;
 952         struct videomode vm;
 953         int ret;
 954         int i;
 955 
 956         sinfo->config = (struct atmel_lcdfb_config*)
 957                 of_match_device(atmel_lcdfb_dt_ids, dev)->data;
 958 
 959         display_np = of_parse_phandle(np, "display", 0);
 960         if (!display_np) {
 961                 dev_err(dev, "failed to find display phandle\n");
 962                 return -ENOENT;
 963         }
 964 
 965         ret = of_property_read_u32(display_np, "bits-per-pixel", &var->bits_per_pixel);
 966         if (ret < 0) {
 967                 dev_err(dev, "failed to get property bits-per-pixel\n");
 968                 goto put_display_node;
 969         }
 970 
 971         ret = of_property_read_u32(display_np, "atmel,guard-time", &pdata->guard_time);
 972         if (ret < 0) {
 973                 dev_err(dev, "failed to get property atmel,guard-time\n");
 974                 goto put_display_node;
 975         }
 976 
 977         ret = of_property_read_u32(display_np, "atmel,lcdcon2", &pdata->default_lcdcon2);
 978         if (ret < 0) {
 979                 dev_err(dev, "failed to get property atmel,lcdcon2\n");
 980                 goto put_display_node;
 981         }
 982 
 983         ret = of_property_read_u32(display_np, "atmel,dmacon", &pdata->default_dmacon);
 984         if (ret < 0) {
 985                 dev_err(dev, "failed to get property bits-per-pixel\n");
 986                 goto put_display_node;
 987         }
 988 
 989         INIT_LIST_HEAD(&pdata->pwr_gpios);
 990         ret = -ENOMEM;
 991         for (i = 0; i < gpiod_count(dev, "atmel,power-control"); i++) {
 992                 gpiod = devm_gpiod_get_index(dev, "atmel,power-control",
 993                                              i, GPIOD_ASIS);
 994                 if (IS_ERR(gpiod))
 995                         continue;
 996 
 997                 og = devm_kzalloc(dev, sizeof(*og), GFP_KERNEL);
 998                 if (!og)
 999                         goto put_display_node;
1000 
1001                 og->gpiod = gpiod;
1002                 is_gpio_power = true;
1003 
1004                 ret = gpiod_direction_output(gpiod, gpiod_is_active_low(gpiod));
1005                 if (ret) {
1006                         dev_err(dev, "set direction output gpio atmel,power-control[%d] failed\n", i);
1007                         goto put_display_node;
1008                 }
1009                 list_add(&og->list, &pdata->pwr_gpios);
1010         }
1011 
1012         if (is_gpio_power)
1013                 pdata->atmel_lcdfb_power_control = atmel_lcdfb_power_control_gpio;
1014 
1015         ret = atmel_lcdfb_get_of_wiring_modes(display_np);
1016         if (ret < 0) {
1017                 dev_err(dev, "invalid atmel,lcd-wiring-mode\n");
1018                 goto put_display_node;
1019         }
1020         pdata->lcd_wiring_mode = ret;
1021 
1022         pdata->lcdcon_is_backlight = of_property_read_bool(display_np, "atmel,lcdcon-backlight");
1023         pdata->lcdcon_pol_negative = of_property_read_bool(display_np, "atmel,lcdcon-backlight-inverted");
1024 
1025         ret = of_get_videomode(display_np, &vm, OF_USE_NATIVE_MODE);
1026         if (ret) {
1027                 dev_err(dev, "failed to get videomode from DT\n");
1028                 goto put_display_node;
1029         }
1030 
1031         ret = fb_videomode_from_videomode(&vm, &fb_vm);
1032         if (ret < 0)
1033                 goto put_display_node;
1034 
1035         fb_add_videomode(&fb_vm, &info->modelist);
1036 
1037 put_display_node:
1038         of_node_put(display_np);
1039         return ret;
1040 }
1041 
1042 static int __init atmel_lcdfb_probe(struct platform_device *pdev)
1043 {
1044         struct device *dev = &pdev->dev;
1045         struct fb_info *info;
1046         struct atmel_lcdfb_info *sinfo;
1047         struct resource *regs = NULL;
1048         struct resource *map = NULL;
1049         struct fb_modelist *modelist;
1050         int ret;
1051 
1052         dev_dbg(dev, "%s BEGIN\n", __func__);
1053 
1054         ret = -ENOMEM;
1055         info = framebuffer_alloc(sizeof(struct atmel_lcdfb_info), dev);
1056         if (!info)
1057                 goto out;
1058 
1059         sinfo = info->par;
1060         sinfo->pdev = pdev;
1061         sinfo->info = info;
1062 
1063         INIT_LIST_HEAD(&info->modelist);
1064 
1065         if (pdev->dev.of_node) {
1066                 ret = atmel_lcdfb_of_init(sinfo);
1067                 if (ret)
1068                         goto free_info;
1069         } else {
1070                 dev_err(dev, "cannot get default configuration\n");
1071                 goto free_info;
1072         }
1073 
1074         if (!sinfo->config)
1075                 goto free_info;
1076 
1077         sinfo->reg_lcd = devm_regulator_get(&pdev->dev, "lcd");
1078         if (IS_ERR(sinfo->reg_lcd))
1079                 sinfo->reg_lcd = NULL;
1080 
1081         info->flags = FBINFO_DEFAULT | FBINFO_PARTIAL_PAN_OK |
1082                       FBINFO_HWACCEL_YPAN;
1083         info->pseudo_palette = sinfo->pseudo_palette;
1084         info->fbops = &atmel_lcdfb_ops;
1085 
1086         info->fix = atmel_lcdfb_fix;
1087         strcpy(info->fix.id, sinfo->pdev->name);
1088 
1089         /* Enable LCDC Clocks */
1090         sinfo->bus_clk = clk_get(dev, "hclk");
1091         if (IS_ERR(sinfo->bus_clk)) {
1092                 ret = PTR_ERR(sinfo->bus_clk);
1093                 goto free_info;
1094         }
1095         sinfo->lcdc_clk = clk_get(dev, "lcdc_clk");
1096         if (IS_ERR(sinfo->lcdc_clk)) {
1097                 ret = PTR_ERR(sinfo->lcdc_clk);
1098                 goto put_bus_clk;
1099         }
1100         atmel_lcdfb_start_clock(sinfo);
1101 
1102         modelist = list_first_entry(&info->modelist,
1103                         struct fb_modelist, list);
1104         fb_videomode_to_var(&info->var, &modelist->mode);
1105 
1106         atmel_lcdfb_check_var(&info->var, info);
1107 
1108         regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1109         if (!regs) {
1110                 dev_err(dev, "resources unusable\n");
1111                 ret = -ENXIO;
1112                 goto stop_clk;
1113         }
1114 
1115         sinfo->irq_base = platform_get_irq(pdev, 0);
1116         if (sinfo->irq_base < 0) {
1117                 dev_err(dev, "unable to get irq\n");
1118                 ret = sinfo->irq_base;
1119                 goto stop_clk;
1120         }
1121 
1122         /* Initialize video memory */
1123         map = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1124         if (map) {
1125                 /* use a pre-allocated memory buffer */
1126                 info->fix.smem_start = map->start;
1127                 info->fix.smem_len = resource_size(map);
1128                 if (!request_mem_region(info->fix.smem_start,
1129                                         info->fix.smem_len, pdev->name)) {
1130                         ret = -EBUSY;
1131                         goto stop_clk;
1132                 }
1133 
1134                 info->screen_base = ioremap_wc(info->fix.smem_start,
1135                                                info->fix.smem_len);
1136                 if (!info->screen_base) {
1137                         ret = -ENOMEM;
1138                         goto release_intmem;
1139                 }
1140 
1141                 /*
1142                  * Don't clear the framebuffer -- someone may have set
1143                  * up a splash image.
1144                  */
1145         } else {
1146                 /* allocate memory buffer */
1147                 ret = atmel_lcdfb_alloc_video_memory(sinfo);
1148                 if (ret < 0) {
1149                         dev_err(dev, "cannot allocate framebuffer: %d\n", ret);
1150                         goto stop_clk;
1151                 }
1152         }
1153 
1154         /* LCDC registers */
1155         info->fix.mmio_start = regs->start;
1156         info->fix.mmio_len = resource_size(regs);
1157 
1158         if (!request_mem_region(info->fix.mmio_start,
1159                                 info->fix.mmio_len, pdev->name)) {
1160                 ret = -EBUSY;
1161                 goto free_fb;
1162         }
1163 
1164         sinfo->mmio = ioremap(info->fix.mmio_start, info->fix.mmio_len);
1165         if (!sinfo->mmio) {
1166                 dev_err(dev, "cannot map LCDC registers\n");
1167                 ret = -ENOMEM;
1168                 goto release_mem;
1169         }
1170 
1171         /* Initialize PWM for contrast or backlight ("off") */
1172         init_contrast(sinfo);
1173 
1174         /* interrupt */
1175         ret = request_irq(sinfo->irq_base, atmel_lcdfb_interrupt, 0, pdev->name, info);
1176         if (ret) {
1177                 dev_err(dev, "request_irq failed: %d\n", ret);
1178                 goto unmap_mmio;
1179         }
1180 
1181         /* Some operations on the LCDC might sleep and
1182          * require a preemptible task context */
1183         INIT_WORK(&sinfo->task, atmel_lcdfb_task);
1184 
1185         ret = atmel_lcdfb_init_fbinfo(sinfo);
1186         if (ret < 0) {
1187                 dev_err(dev, "init fbinfo failed: %d\n", ret);
1188                 goto unregister_irqs;
1189         }
1190 
1191         ret = atmel_lcdfb_set_par(info);
1192         if (ret < 0) {
1193                 dev_err(dev, "set par failed: %d\n", ret);
1194                 goto unregister_irqs;
1195         }
1196 
1197         dev_set_drvdata(dev, info);
1198 
1199         /*
1200          * Tell the world that we're ready to go
1201          */
1202         ret = register_framebuffer(info);
1203         if (ret < 0) {
1204                 dev_err(dev, "failed to register framebuffer device: %d\n", ret);
1205                 goto reset_drvdata;
1206         }
1207 
1208         /* Power up the LCDC screen */
1209         atmel_lcdfb_power_control(sinfo, 1);
1210 
1211         dev_info(dev, "fb%d: Atmel LCDC at 0x%08lx (mapped at %p), irq %d\n",
1212                        info->node, info->fix.mmio_start, sinfo->mmio, sinfo->irq_base);
1213 
1214         return 0;
1215 
1216 reset_drvdata:
1217         dev_set_drvdata(dev, NULL);
1218         fb_dealloc_cmap(&info->cmap);
1219 unregister_irqs:
1220         cancel_work_sync(&sinfo->task);
1221         free_irq(sinfo->irq_base, info);
1222 unmap_mmio:
1223         exit_backlight(sinfo);
1224         iounmap(sinfo->mmio);
1225 release_mem:
1226         release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
1227 free_fb:
1228         if (map)
1229                 iounmap(info->screen_base);
1230         else
1231                 atmel_lcdfb_free_video_memory(sinfo);
1232 
1233 release_intmem:
1234         if (map)
1235                 release_mem_region(info->fix.smem_start, info->fix.smem_len);
1236 stop_clk:
1237         atmel_lcdfb_stop_clock(sinfo);
1238         clk_put(sinfo->lcdc_clk);
1239 put_bus_clk:
1240         clk_put(sinfo->bus_clk);
1241 free_info:
1242         framebuffer_release(info);
1243 out:
1244         dev_dbg(dev, "%s FAILED\n", __func__);
1245         return ret;
1246 }
1247 
1248 static int __exit atmel_lcdfb_remove(struct platform_device *pdev)
1249 {
1250         struct device *dev = &pdev->dev;
1251         struct fb_info *info = dev_get_drvdata(dev);
1252         struct atmel_lcdfb_info *sinfo;
1253 
1254         if (!info || !info->par)
1255                 return 0;
1256         sinfo = info->par;
1257 
1258         cancel_work_sync(&sinfo->task);
1259         exit_backlight(sinfo);
1260         atmel_lcdfb_power_control(sinfo, 0);
1261         unregister_framebuffer(info);
1262         atmel_lcdfb_stop_clock(sinfo);
1263         clk_put(sinfo->lcdc_clk);
1264         clk_put(sinfo->bus_clk);
1265         fb_dealloc_cmap(&info->cmap);
1266         free_irq(sinfo->irq_base, info);
1267         iounmap(sinfo->mmio);
1268         release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
1269         if (platform_get_resource(pdev, IORESOURCE_MEM, 1)) {
1270                 iounmap(info->screen_base);
1271                 release_mem_region(info->fix.smem_start, info->fix.smem_len);
1272         } else {
1273                 atmel_lcdfb_free_video_memory(sinfo);
1274         }
1275 
1276         framebuffer_release(info);
1277 
1278         return 0;
1279 }
1280 
1281 #ifdef CONFIG_PM
1282 
1283 static int atmel_lcdfb_suspend(struct platform_device *pdev, pm_message_t mesg)
1284 {
1285         struct fb_info *info = platform_get_drvdata(pdev);
1286         struct atmel_lcdfb_info *sinfo = info->par;
1287 
1288         /*
1289          * We don't want to handle interrupts while the clock is
1290          * stopped. It may take forever.
1291          */
1292         lcdc_writel(sinfo, ATMEL_LCDC_IDR, ~0U);
1293 
1294         sinfo->saved_lcdcon = lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_CTR);
1295         lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, 0);
1296         atmel_lcdfb_power_control(sinfo, 0);
1297         atmel_lcdfb_stop(sinfo);
1298         atmel_lcdfb_stop_clock(sinfo);
1299 
1300         return 0;
1301 }
1302 
1303 static int atmel_lcdfb_resume(struct platform_device *pdev)
1304 {
1305         struct fb_info *info = platform_get_drvdata(pdev);
1306         struct atmel_lcdfb_info *sinfo = info->par;
1307 
1308         atmel_lcdfb_start_clock(sinfo);
1309         atmel_lcdfb_start(sinfo);
1310         atmel_lcdfb_power_control(sinfo, 1);
1311         lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, sinfo->saved_lcdcon);
1312 
1313         /* Enable FIFO & DMA errors */
1314         lcdc_writel(sinfo, ATMEL_LCDC_IER, ATMEL_LCDC_UFLWI
1315                         | ATMEL_LCDC_OWRI | ATMEL_LCDC_MERI);
1316 
1317         return 0;
1318 }
1319 
1320 #else
1321 #define atmel_lcdfb_suspend     NULL
1322 #define atmel_lcdfb_resume      NULL
1323 #endif
1324 
1325 static struct platform_driver atmel_lcdfb_driver = {
1326         .remove         = __exit_p(atmel_lcdfb_remove),
1327         .suspend        = atmel_lcdfb_suspend,
1328         .resume         = atmel_lcdfb_resume,
1329         .driver         = {
1330                 .name   = "atmel_lcdfb",
1331                 .of_match_table = of_match_ptr(atmel_lcdfb_dt_ids),
1332         },
1333 };
1334 
1335 module_platform_driver_probe(atmel_lcdfb_driver, atmel_lcdfb_probe);
1336 
1337 MODULE_DESCRIPTION("AT91 LCD Controller framebuffer driver");
1338 MODULE_AUTHOR("Nicolas Ferre <nicolas.ferre@atmel.com>");
1339 MODULE_LICENSE("GPL");
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/video/fbdev/atmel_lcdfb.c

DEFINITIONS
