drivers/video/fbdev/clps711x-fb.c

   1 /*
   2  * Cirrus Logic CLPS711X FB driver
   3  *
   4  * Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
   5  * Based on driver by Russell King <rmk@arm.linux.org.uk>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  */
  12
  13 #include <linux/clk.h>
  14 #include <linux/fb.h>
  15 #include <linux/io.h>
  16 #include <linux/lcd.h>
  17 #include <linux/module.h>
  18 #include <linux/of.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/regmap.h>
  21 #include <linux/mfd/syscon.h>
  22 #include <linux/mfd/syscon/clps711x.h>
  23 #include <linux/regulator/consumer.h>
  24 #include <video/of_display_timing.h>
  25
  26 #define CLPS711X_FB_NAME        "clps711x-fb"
  27 #define CLPS711X_FB_BPP_MAX     (4)
  28
  29 /* Registers relative to LCDCON */
  30 #define CLPS711X_LCDCON         (0x0000)
  31 # define LCDCON_GSEN            BIT(30)
  32 # define LCDCON_GSMD            BIT(31)
  33 #define CLPS711X_PALLSW         (0x0280)
  34 #define CLPS711X_PALMSW         (0x02c0)
  35 #define CLPS711X_FBADDR         (0x0d40)
  36
  37 struct clps711x_fb_info {
  38         struct clk              *clk;
  39         void __iomem            *base;
  40         struct regmap           *syscon;
  41         resource_size_t         buffsize;
  42         struct fb_videomode     mode;
  43         struct regulator        *lcd_pwr;
  44         u32                     ac_prescale;
  45         bool                    cmap_invert;
  46 };
  47
  48 static int clps711x_fb_setcolreg(u_int regno, u_int red, u_int green,
  49                                  u_int blue, u_int transp, struct fb_info *info)
  50 {
  51         struct clps711x_fb_info *cfb = info->par;
  52         u32 level, mask, shift;
  53
  54         if (regno >= BIT(info->var.bits_per_pixel))
  55                 return -EINVAL;
  56
  57         shift = 4 * (regno & 7);
  58         mask  = 0xf << shift;
  59         /* gray = 0.30*R + 0.58*G + 0.11*B */
  60         level = (((red * 77 + green * 151 + blue * 28) >> 20) << shift) & mask;
  61         if (cfb->cmap_invert)
  62                 level = 0xf - level;
  63
  64         regno = (regno < 8) ? CLPS711X_PALLSW : CLPS711X_PALMSW;
  65
  66         writel((readl(cfb->base + regno) & ~mask) | level, cfb->base + regno);
  67
  68         return 0;
  69 }
  70
  71 static int clps711x_fb_check_var(struct fb_var_screeninfo *var,
  72                                  struct fb_info *info)
  73 {
  74         u32 val;
  75
  76         if (var->bits_per_pixel < 1 ||
  77             var->bits_per_pixel > CLPS711X_FB_BPP_MAX)
  78                 return -EINVAL;
  79
  80         if (!var->pixclock)
  81                 return -EINVAL;
  82
  83         val = DIV_ROUND_UP(var->xres, 16) - 1;
  84         if (val < 0x01 || val > 0x3f)
  85                 return -EINVAL;
  86
  87         val = DIV_ROUND_UP(var->yres * var->xres * var->bits_per_pixel, 128);
  88         val--;
  89         if (val < 0x001 || val > 0x1fff)
  90                 return -EINVAL;
  91
  92         var->transp.msb_right   = 0;
  93         var->transp.offset      = 0;
  94         var->transp.length      = 0;
  95         var->red.msb_right      = 0;
  96         var->red.offset         = 0;
  97         var->red.length         = var->bits_per_pixel;
  98         var->green              = var->red;
  99         var->blue               = var->red;
 100         var->grayscale          = var->bits_per_pixel > 1;
 101
 102         return 0;
 103 }
 104
 105 static int clps711x_fb_set_par(struct fb_info *info)
 106 {
 107         struct clps711x_fb_info *cfb = info->par;
 108         resource_size_t size;
 109         u32 lcdcon, pps;
 110
 111         size = (info->var.xres * info->var.yres * info->var.bits_per_pixel) / 8;
 112         if (size > cfb->buffsize)
 113                 return -EINVAL;
 114
 115         switch (info->var.bits_per_pixel) {
 116         case 1:
 117                 info->fix.visual = FB_VISUAL_MONO01;
 118                 break;
 119         case 2:
 120         case 4:
 121                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
 122                 break;
 123         default:
 124                 return -EINVAL;
 125         }
 126
 127         info->fix.line_length = info->var.xres * info->var.bits_per_pixel / 8;
 128         info->fix.smem_len = size;
 129
 130         lcdcon = (info->var.xres * info->var.yres *
 131                   info->var.bits_per_pixel) / 128 - 1;
 132         lcdcon |= ((info->var.xres / 16) - 1) << 13;
 133         lcdcon |= (cfb->ac_prescale & 0x1f) << 25;
 134
 135         pps = clk_get_rate(cfb->clk) / (PICOS2KHZ(info->var.pixclock) * 1000);
 136         if (pps)
 137                 pps--;
 138         lcdcon |= (pps & 0x3f) << 19;
 139
 140         if (info->var.bits_per_pixel == 4)
 141                 lcdcon |= LCDCON_GSMD;
 142         if (info->var.bits_per_pixel >= 2)
 143                 lcdcon |= LCDCON_GSEN;
 144
 145         /* LCDCON must only be changed while the LCD is disabled */
 146         regmap_update_bits(cfb->syscon, SYSCON_OFFSET, SYSCON1_LCDEN, 0);
 147         writel(lcdcon, cfb->base + CLPS711X_LCDCON);
 148         regmap_update_bits(cfb->syscon, SYSCON_OFFSET,
 149                            SYSCON1_LCDEN, SYSCON1_LCDEN);
 150
 151         return 0;
 152 }
 153
 154 static int clps711x_fb_blank(int blank, struct fb_info *info)
 155 {
 156         /* Return happy */
 157         return 0;
 158 }
 159
 160 static struct fb_ops clps711x_fb_ops = {
 161         .owner          = THIS_MODULE,
 162         .fb_setcolreg   = clps711x_fb_setcolreg,
 163         .fb_check_var   = clps711x_fb_check_var,
 164         .fb_set_par     = clps711x_fb_set_par,
 165         .fb_blank       = clps711x_fb_blank,
 166         .fb_fillrect    = sys_fillrect,
 167         .fb_copyarea    = sys_copyarea,
 168         .fb_imageblit   = sys_imageblit,
 169 };
 170
 171 static int clps711x_lcd_check_fb(struct lcd_device *lcddev, struct fb_info *fi)
 172 {
 173         struct clps711x_fb_info *cfb = dev_get_drvdata(&lcddev->dev);
 174
 175         return (!fi || fi->par == cfb) ? 1 : 0;
 176 }
 177
 178 static int clps711x_lcd_get_power(struct lcd_device *lcddev)
 179 {
 180         struct clps711x_fb_info *cfb = dev_get_drvdata(&lcddev->dev);
 181
 182         if (!IS_ERR_OR_NULL(cfb->lcd_pwr))
 183                 if (!regulator_is_enabled(cfb->lcd_pwr))
 184                         return FB_BLANK_NORMAL;
 185
 186         return FB_BLANK_UNBLANK;
 187 }
 188
 189 static int clps711x_lcd_set_power(struct lcd_device *lcddev, int blank)
 190 {
 191         struct clps711x_fb_info *cfb = dev_get_drvdata(&lcddev->dev);
 192
 193         if (!IS_ERR_OR_NULL(cfb->lcd_pwr)) {
 194                 if (blank == FB_BLANK_UNBLANK) {
 195                         if (!regulator_is_enabled(cfb->lcd_pwr))
 196                                 return regulator_enable(cfb->lcd_pwr);
 197                 } else {
 198                         if (regulator_is_enabled(cfb->lcd_pwr))
 199                                 return regulator_disable(cfb->lcd_pwr);
 200                 }
 201         }
 202
 203         return 0;
 204 }
 205
 206 static struct lcd_ops clps711x_lcd_ops = {
 207         .check_fb       = clps711x_lcd_check_fb,
 208         .get_power      = clps711x_lcd_get_power,
 209         .set_power      = clps711x_lcd_set_power,
 210 };
 211
 212 static int clps711x_fb_probe(struct platform_device *pdev)
 213 {
 214         struct device *dev = &pdev->dev;
 215         struct device_node *disp, *np = dev->of_node;
 216         struct clps711x_fb_info *cfb;
 217         struct lcd_device *lcd;
 218         struct fb_info *info;
 219         struct resource *res;
 220         int ret = -ENOENT;
 221         u32 val;
 222
 223         if (fb_get_options(CLPS711X_FB_NAME, NULL))
 224                 return -ENODEV;
 225
 226         info = framebuffer_alloc(sizeof(*cfb), dev);
 227         if (!info)
 228                 return -ENOMEM;
 229
 230         cfb = info->par;
 231         platform_set_drvdata(pdev, info);
 232
 233         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 234         if (!res)
 235                 goto out_fb_release;
 236         cfb->base = devm_ioremap(dev, res->start, resource_size(res));
 237         if (!cfb->base) {
 238                 ret = -ENOMEM;
 239                 goto out_fb_release;
 240         }
 241
 242         info->fix.mmio_start = res->start;
 243         info->fix.mmio_len = resource_size(res);
 244
 245         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 246         info->screen_base = devm_ioremap_resource(dev, res);
 247         if (IS_ERR(info->screen_base)) {
 248                 ret = PTR_ERR(info->screen_base);
 249                 goto out_fb_release;
 250         }
 251
 252         /* Physical address should be aligned to 256 MiB */
 253         if (res->start & 0x0fffffff) {
 254                 ret = -EINVAL;
 255                 goto out_fb_release;
 256         }
 257
 258         info->apertures = alloc_apertures(1);
 259         if (!info->apertures) {
 260                 ret = -ENOMEM;
 261                 goto out_fb_release;
 262         }
 263
 264         cfb->buffsize = resource_size(res);
 265         info->fix.smem_start = res->start;
 266         info->apertures->ranges[0].base = info->fix.smem_start;
 267         info->apertures->ranges[0].size = cfb->buffsize;
 268
 269         cfb->clk = devm_clk_get(dev, NULL);
 270         if (IS_ERR(cfb->clk)) {
 271                 ret = PTR_ERR(cfb->clk);
 272                 goto out_fb_release;
 273         }
 274
 275         cfb->syscon =
 276                 syscon_regmap_lookup_by_compatible("cirrus,clps711x-syscon1");
 277         if (IS_ERR(cfb->syscon)) {
 278                 ret = PTR_ERR(cfb->syscon);
 279                 goto out_fb_release;
 280         }
 281
 282         disp = of_parse_phandle(np, "display", 0);
 283         if (!disp) {
 284                 dev_err(&pdev->dev, "No display defined\n");
 285                 ret = -ENODATA;
 286                 goto out_fb_release;
 287         }
 288
 289         ret = of_get_fb_videomode(disp, &cfb->mode, OF_USE_NATIVE_MODE);
 290         if (ret)
 291                 goto out_fb_release;
 292
 293         of_property_read_u32(disp, "ac-prescale", &cfb->ac_prescale);
 294         cfb->cmap_invert = of_property_read_bool(disp, "cmap-invert");
 295
 296         ret = of_property_read_u32(disp, "bits-per-pixel",
 297                                    &info->var.bits_per_pixel);
 298         if (ret)
 299                 goto out_fb_release;
 300
 301         /* Force disable LCD on any mismatch */
 302         if (info->fix.smem_start != (readb(cfb->base + CLPS711X_FBADDR) << 28))
 303                 regmap_update_bits(cfb->syscon, SYSCON_OFFSET,
 304                                    SYSCON1_LCDEN, 0);
 305
 306         ret = regmap_read(cfb->syscon, SYSCON_OFFSET, &val);
 307         if (ret)
 308                 goto out_fb_release;
 309
 310         if (!(val & SYSCON1_LCDEN)) {
 311                 /* Setup start FB address */
 312                 writeb(info->fix.smem_start >> 28, cfb->base + CLPS711X_FBADDR);
 313                 /* Clean FB memory */
 314                 memset_io(info->screen_base, 0, cfb->buffsize);
 315         }
 316
 317         cfb->lcd_pwr = devm_regulator_get(dev, "lcd");
 318         if (PTR_ERR(cfb->lcd_pwr) == -EPROBE_DEFER) {
 319                 ret = -EPROBE_DEFER;
 320                 goto out_fb_release;
 321         }
 322
 323         info->fbops = &clps711x_fb_ops;
 324         info->flags = FBINFO_DEFAULT;
 325         info->var.activate = FB_ACTIVATE_FORCE | FB_ACTIVATE_NOW;
 326         info->var.height = -1;
 327         info->var.width = -1;
 328         info->var.vmode = FB_VMODE_NONINTERLACED;
 329         info->fix.type = FB_TYPE_PACKED_PIXELS;
 330         info->fix.accel = FB_ACCEL_NONE;
 331         strlcpy(info->fix.id, CLPS711X_FB_NAME, sizeof(info->fix.id));
 332         fb_videomode_to_var(&info->var, &cfb->mode);
 333
 334         ret = fb_alloc_cmap(&info->cmap, BIT(CLPS711X_FB_BPP_MAX), 0);
 335         if (ret)
 336                 goto out_fb_release;
 337
 338         ret = fb_set_var(info, &info->var);
 339         if (ret)
 340                 goto out_fb_dealloc_cmap;
 341
 342         ret = register_framebuffer(info);
 343         if (ret)
 344                 goto out_fb_dealloc_cmap;
 345
 346         lcd = devm_lcd_device_register(dev, "clps711x-lcd", dev, cfb,
 347                                        &clps711x_lcd_ops);
 348         if (!IS_ERR(lcd))
 349                 return 0;
 350
 351         ret = PTR_ERR(lcd);
 352         unregister_framebuffer(info);
 353
 354 out_fb_dealloc_cmap:
 355         regmap_update_bits(cfb->syscon, SYSCON_OFFSET, SYSCON1_LCDEN, 0);
 356         fb_dealloc_cmap(&info->cmap);
 357
 358 out_fb_release:
 359         framebuffer_release(info);
 360
 361         return ret;
 362 }
 363
 364 static int clps711x_fb_remove(struct platform_device *pdev)
 365 {
 366         struct fb_info *info = platform_get_drvdata(pdev);
 367         struct clps711x_fb_info *cfb = info->par;
 368
 369         regmap_update_bits(cfb->syscon, SYSCON_OFFSET, SYSCON1_LCDEN, 0);
 370
 371         unregister_framebuffer(info);
 372         fb_dealloc_cmap(&info->cmap);
 373         framebuffer_release(info);
 374
 375         return 0;
 376 }
 377
 378 static const struct of_device_id clps711x_fb_dt_ids[] = {
 379         { .compatible = "cirrus,clps711x-fb", },
 380         { }
 381 };
 382 MODULE_DEVICE_TABLE(of, clps711x_fb_dt_ids);
 383
 384 static struct platform_driver clps711x_fb_driver = {
 385         .driver = {
 386                 .name           = CLPS711X_FB_NAME,
 387                 .of_match_table = clps711x_fb_dt_ids,
 388         },
 389         .probe  = clps711x_fb_probe,
 390         .remove = clps711x_fb_remove,
 391 };
 392 module_platform_driver(clps711x_fb_driver);
 393
 394 MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
 395 MODULE_DESCRIPTION("Cirrus Logic CLPS711X FB driver");
 396 MODULE_LICENSE("GPL");