drivers/staging/fbtft/fb_ra8875.c

   1 /*
   2  * FBTFT driver for the RA8875 LCD Controller
   3  * Copyright by Pf@nne & NOTRO
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/kernel.h>
  18 #include <linux/init.h>
  19 #include <linux/delay.h>
  20
  21 #include <linux/gpio.h>
  22 #include "fbtft.h"
  23
  24 #define DRVNAME "fb_ra8875"
  25
  26 static int write_spi(struct fbtft_par *par, void *buf, size_t len)
  27 {
  28         struct spi_transfer t = {
  29                 .tx_buf = buf,
  30                 .len = len,
  31                 .speed_hz = 1000000,
  32         };
  33         struct spi_message m;
  34
  35         fbtft_par_dbg_hex(DEBUG_WRITE, par, par->info->device, u8, buf, len,
  36                           "%s(len=%d): ", __func__, len);
  37
  38         if (!par->spi) {
  39                 dev_err(par->info->device,
  40                         "%s: par->spi is unexpectedly NULL\n", __func__);
  41                 return -1;
  42         }
  43
  44         spi_message_init(&m);
  45         spi_message_add_tail(&t, &m);
  46         return spi_sync(par->spi, &m);
  47 }
  48
  49 static int init_display(struct fbtft_par *par)
  50 {
  51         gpio_set_value(par->gpio.dc, 1);
  52
  53         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
  54                       "%s()\n", __func__);
  55         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
  56                       "display size %dx%d\n",
  57                 par->info->var.xres,
  58                 par->info->var.yres);
  59
  60         par->fbtftops.reset(par);
  61
  62         if ((par->info->var.xres == 320) && (par->info->var.yres == 240)) {
  63                 /* PLL clock frequency */
  64                 write_reg(par, 0x88, 0x0A);
  65                 write_reg(par, 0x89, 0x02);
  66                 mdelay(10);
  67                 /* color deep / MCU Interface */
  68                 write_reg(par, 0x10, 0x0C);
  69                 /* pixel clock period  */
  70                 write_reg(par, 0x04, 0x03);
  71                 mdelay(1);
  72                 /* horizontal settings */
  73                 write_reg(par, 0x14, 0x27);
  74                 write_reg(par, 0x15, 0x00);
  75                 write_reg(par, 0x16, 0x05);
  76                 write_reg(par, 0x17, 0x04);
  77                 write_reg(par, 0x18, 0x03);
  78                 /* vertical settings */
  79                 write_reg(par, 0x19, 0xEF);
  80                 write_reg(par, 0x1A, 0x00);
  81                 write_reg(par, 0x1B, 0x05);
  82                 write_reg(par, 0x1C, 0x00);
  83                 write_reg(par, 0x1D, 0x0E);
  84                 write_reg(par, 0x1E, 0x00);
  85                 write_reg(par, 0x1F, 0x02);
  86         } else if ((par->info->var.xres == 480) &&
  87                    (par->info->var.yres == 272)) {
  88                 /* PLL clock frequency  */
  89                 write_reg(par, 0x88, 0x0A);
  90                 write_reg(par, 0x89, 0x02);
  91                 mdelay(10);
  92                 /* color deep / MCU Interface */
  93                 write_reg(par, 0x10, 0x0C);
  94                 /* pixel clock period  */
  95                 write_reg(par, 0x04, 0x82);
  96                 mdelay(1);
  97                 /* horizontal settings */
  98                 write_reg(par, 0x14, 0x3B);
  99                 write_reg(par, 0x15, 0x00);
 100                 write_reg(par, 0x16, 0x01);
 101                 write_reg(par, 0x17, 0x00);
 102                 write_reg(par, 0x18, 0x05);
 103                 /* vertical settings */
 104                 write_reg(par, 0x19, 0x0F);
 105                 write_reg(par, 0x1A, 0x01);
 106                 write_reg(par, 0x1B, 0x02);
 107                 write_reg(par, 0x1C, 0x00);
 108                 write_reg(par, 0x1D, 0x07);
 109                 write_reg(par, 0x1E, 0x00);
 110                 write_reg(par, 0x1F, 0x09);
 111         } else if ((par->info->var.xres == 640) &&
 112                    (par->info->var.yres == 480)) {
 113                 /* PLL clock frequency */
 114                 write_reg(par, 0x88, 0x0B);
 115                 write_reg(par, 0x89, 0x02);
 116                 mdelay(10);
 117                 /* color deep / MCU Interface */
 118                 write_reg(par, 0x10, 0x0C);
 119                 /* pixel clock period */
 120                 write_reg(par, 0x04, 0x01);
 121                 mdelay(1);
 122                 /* horizontal settings */
 123                 write_reg(par, 0x14, 0x4F);
 124                 write_reg(par, 0x15, 0x05);
 125                 write_reg(par, 0x16, 0x0F);
 126                 write_reg(par, 0x17, 0x01);
 127                 write_reg(par, 0x18, 0x00);
 128                 /* vertical settings */
 129                 write_reg(par, 0x19, 0xDF);
 130                 write_reg(par, 0x1A, 0x01);
 131                 write_reg(par, 0x1B, 0x0A);
 132                 write_reg(par, 0x1C, 0x00);
 133                 write_reg(par, 0x1D, 0x0E);
 134                 write_reg(par, 0x1E, 0x00);
 135                 write_reg(par, 0x1F, 0x01);
 136         } else if ((par->info->var.xres == 800) &&
 137                    (par->info->var.yres == 480)) {
 138                 /* PLL clock frequency */
 139                 write_reg(par, 0x88, 0x0B);
 140                 write_reg(par, 0x89, 0x02);
 141                 mdelay(10);
 142                 /* color deep / MCU Interface */
 143                 write_reg(par, 0x10, 0x0C);
 144                 /* pixel clock period */
 145                 write_reg(par, 0x04, 0x81);
 146                 mdelay(1);
 147                 /* horizontal settings */
 148                 write_reg(par, 0x14, 0x63);
 149                 write_reg(par, 0x15, 0x03);
 150                 write_reg(par, 0x16, 0x03);
 151                 write_reg(par, 0x17, 0x02);
 152                 write_reg(par, 0x18, 0x00);
 153                 /* vertical settings */
 154                 write_reg(par, 0x19, 0xDF);
 155                 write_reg(par, 0x1A, 0x01);
 156                 write_reg(par, 0x1B, 0x14);
 157                 write_reg(par, 0x1C, 0x00);
 158                 write_reg(par, 0x1D, 0x06);
 159                 write_reg(par, 0x1E, 0x00);
 160                 write_reg(par, 0x1F, 0x01);
 161         } else {
 162                 dev_err(par->info->device, "display size is not supported!!");
 163                 return -1;
 164         }
 165
 166         /* PWM clock */
 167         write_reg(par, 0x8a, 0x81);
 168         write_reg(par, 0x8b, 0xFF);
 169         mdelay(10);
 170
 171         /* Display ON */
 172         write_reg(par, 0x01, 0x80);
 173         mdelay(10);
 174
 175         return 0;
 176 }
 177
 178 static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
 179 {
 180         /* Set_Active_Window */
 181         write_reg(par, 0x30, xs & 0x00FF);
 182         write_reg(par, 0x31, (xs & 0xFF00) >> 8);
 183         write_reg(par, 0x32, ys & 0x00FF);
 184         write_reg(par, 0x33, (ys & 0xFF00) >> 8);
 185         write_reg(par, 0x34, (xs + xe) & 0x00FF);
 186         write_reg(par, 0x35, ((xs + xe) & 0xFF00) >> 8);
 187         write_reg(par, 0x36, (ys + ye) & 0x00FF);
 188         write_reg(par, 0x37, ((ys + ye) & 0xFF00) >> 8);
 189
 190         /* Set_Memory_Write_Cursor */
 191         write_reg(par, 0x46,  xs & 0xff);
 192         write_reg(par, 0x47, (xs >> 8) & 0x03);
 193         write_reg(par, 0x48,  ys & 0xff);
 194         write_reg(par, 0x49, (ys >> 8) & 0x01);
 195
 196         write_reg(par, 0x02);
 197 }
 198
 199 static void write_reg8_bus8(struct fbtft_par *par, int len, ...)
 200 {
 201         va_list args;
 202         int i, ret;
 203         u8 *buf = par->buf;
 204
 205         /* slow down spi-speed for writing registers */
 206         par->fbtftops.write = write_spi;
 207
 208         if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) {
 209                 va_start(args, len);
 210                 for (i = 0; i < len; i++)
 211                         buf[i] = (u8)va_arg(args, unsigned int);
 212                 va_end(args);
 213                 fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device,
 214                                   u8, buf, len, "%s: ", __func__);
 215         }
 216
 217         va_start(args, len);
 218         *buf++ = 0x80;
 219         *buf = (u8)va_arg(args, unsigned int);
 220         ret = par->fbtftops.write(par, par->buf, 2);
 221         if (ret < 0) {
 222                 va_end(args);
 223                 dev_err(par->info->device, "write() failed and returned %dn",
 224                         ret);
 225                 return;
 226         }
 227         len--;
 228
 229         udelay(100);
 230
 231         if (len) {
 232                 buf = (u8 *)par->buf;
 233                 *buf++ = 0x00;
 234                 i = len;
 235                 while (i--)
 236                         *buf++ = (u8)va_arg(args, unsigned int);
 237
 238                 ret = par->fbtftops.write(par, par->buf, len + 1);
 239                 if (ret < 0) {
 240                         va_end(args);
 241                         dev_err(par->info->device,
 242                                 "write() failed and returned %dn", ret);
 243                         return;
 244                 }
 245         }
 246         va_end(args);
 247
 248         /* restore user spi-speed */
 249         par->fbtftops.write = fbtft_write_spi;
 250         udelay(100);
 251 }
 252
 253 static int write_vmem16_bus8(struct fbtft_par *par, size_t offset, size_t len)
 254 {
 255         u16 *vmem16;
 256         __be16 *txbuf16 = par->txbuf.buf;
 257         size_t remain;
 258         size_t to_copy;
 259         size_t tx_array_size;
 260         int i;
 261         int ret = 0;
 262         size_t startbyte_size = 0;
 263
 264         fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s(offset=%zu, len=%zu)\n",
 265                       __func__, offset, len);
 266
 267         remain = len / 2;
 268         vmem16 = (u16 *)(par->info->screen_buffer + offset);
 269         tx_array_size = par->txbuf.len / 2;
 270                 txbuf16 = par->txbuf.buf + 1;
 271                 tx_array_size -= 2;
 272                 *(u8 *)(par->txbuf.buf) = 0x00;
 273                 startbyte_size = 1;
 274
 275         while (remain) {
 276                 to_copy = min(tx_array_size, remain);
 277                 dev_dbg(par->info->device, "    to_copy=%zu, remain=%zu\n",
 278                         to_copy, remain - to_copy);
 279
 280                 for (i = 0; i < to_copy; i++)
 281                         txbuf16[i] = cpu_to_be16(vmem16[i]);
 282
 283                 vmem16 = vmem16 + to_copy;
 284                 ret = par->fbtftops.write(par, par->txbuf.buf,
 285                         startbyte_size + to_copy * 2);
 286                 if (ret < 0)
 287                         return ret;
 288                 remain -= to_copy;
 289         }
 290
 291         return ret;
 292 }
 293
 294 static struct fbtft_display display = {
 295         .regwidth = 8,
 296         .fbtftops = {
 297                 .init_display = init_display,
 298                 .set_addr_win = set_addr_win,
 299                 .write_register = write_reg8_bus8,
 300                 .write_vmem = write_vmem16_bus8,
 301                 .write = write_spi,
 302         },
 303 };
 304
 305 FBTFT_REGISTER_DRIVER(DRVNAME, "raio,ra8875", &display);
 306
 307 MODULE_ALIAS("spi:" DRVNAME);
 308 MODULE_ALIAS("platform:" DRVNAME);
 309 MODULE_ALIAS("spi:ra8875");
 310 MODULE_ALIAS("platform:ra8875");
 311
 312 MODULE_DESCRIPTION("FB driver for the RA8875 LCD Controller");
 313 MODULE_AUTHOR("Pf@nne");
 314 MODULE_LICENSE("GPL");