LXR linux/drivers/staging/fbtft/fb

   1#include <linux/module.h>
   2#include <linux/kernel.h>
   3#include <linux/init.h>
   4#include <linux/gpio.h>
   5#include <linux/spi/spi.h>
   6#include <linux/delay.h>
   7
   8#include "fbtft.h"
   9
  10#define DRVNAME         "fb_ssd1331"
  11#define WIDTH           96
  12#define HEIGHT          64
  13#define GAMMA_NUM       1
  14#define GAMMA_LEN       63
  15#define DEFAULT_GAMMA   "0 2 2 2 2 2 2 2 " \
  16                        "2 2 2 2 2 2 2 2 " \
  17                        "2 2 2 2 2 2 2 2 " \
  18                        "2 2 2 2 2 2 2 2 " \
  19                        "2 2 2 2 2 2 2 2 " \
  20                        "2 2 2 2 2 2 2 2 " \
  21                        "2 2 2 2 2 2 2 2 " \
  22                        "2 2 2 2 2 2 2" \
  23
  24static int init_display(struct fbtft_par *par)
  25{
  26        par->fbtftops.reset(par);
  27
  28        write_reg(par, 0xae); /* Display Off */
  29        write_reg(par, 0xa0, 0x70 | (par->bgr << 2)); /* Set Colour Depth */
  30        write_reg(par, 0x72); /* RGB colour */
  31        write_reg(par, 0xa1, 0x00); /* Set Display Start Line */
  32        write_reg(par, 0xa2, 0x00); /* Set Display Offset */
  33        write_reg(par, 0xa4); /* NORMALDISPLAY */
  34        write_reg(par, 0xa8, 0x3f); /* Set multiplex */
  35        write_reg(par, 0xad, 0x8e); /* Set master */
  36        /* write_reg(par, 0xb0, 0x0b);  Set power mode */
  37        write_reg(par, 0xb1, 0x31); /* Precharge */
  38        write_reg(par, 0xb3, 0xf0); /* Clock div */
  39        write_reg(par, 0x8a, 0x64); /* Precharge A */
  40        write_reg(par, 0x8b, 0x78); /* Precharge B */
  41        write_reg(par, 0x8c, 0x64); /* Precharge C */
  42        write_reg(par, 0xbb, 0x3a); /* Precharge level */
  43        write_reg(par, 0xbe, 0x3e); /* vcomh */
  44        write_reg(par, 0x87, 0x06); /* Master current */
  45        write_reg(par, 0x81, 0x91); /* Contrast A */
  46        write_reg(par, 0x82, 0x50); /* Contrast B */
  47        write_reg(par, 0x83, 0x7d); /* Contrast C */
  48        write_reg(par, 0xaf); /* Set Sleep Mode Display On */
  49
  50        return 0;
  51}
  52
  53static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
  54{
  55        write_reg(par, 0x15, xs, xe);
  56        write_reg(par, 0x75, ys, ye);
  57}
  58
  59static void write_reg8_bus8(struct fbtft_par *par, int len, ...)
  60{
  61        va_list args;
  62        int i, ret;
  63        u8 *buf = par->buf;
  64
  65        if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) {
  66                va_start(args, len);
  67                for (i = 0; i < len; i++)
  68                        buf[i] = (u8)va_arg(args, unsigned int);
  69                va_end(args);
  70                fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device, u8, buf, len, "%s: ", __func__);
  71        }
  72
  73        va_start(args, len);
  74
  75        *buf = (u8)va_arg(args, unsigned int);
  76        if (par->gpio.dc != -1)
  77                gpio_set_value(par->gpio.dc, 0);
  78        ret = par->fbtftops.write(par, par->buf, sizeof(u8));
  79        if (ret < 0) {
  80                va_end(args);
  81                dev_err(par->info->device,
  82                        "write() failed and returned %d\n", ret);
  83                return;
  84        }
  85        len--;
  86
  87        if (len) {
  88                i = len;
  89                while (i--)
  90                        *buf++ = (u8)va_arg(args, unsigned int);
  91                ret = par->fbtftops.write(par, par->buf, len * (sizeof(u8)));
  92                if (ret < 0) {
  93                        va_end(args);
  94                        dev_err(par->info->device,
  95                                "write() failed and returned %d\n", ret);
  96                        return;
  97                }
  98        }
  99        if (par->gpio.dc != -1)
 100                gpio_set_value(par->gpio.dc, 1);
 101        va_end(args);
 102}
 103
 104/*
 105 * Grayscale Lookup Table
 106 * GS1 - GS63
 107 * The driver Gamma curve contains the relative values between the entries
 108 * in the Lookup table.
 109 *
 110 * From datasheet:
 111 * 8.8 Gray Scale Decoder
 112 *
 113 * there are total 180 Gamma Settings (Setting 0 to Setting 180)
 114 * available for the Gray Scale table.
 115 *
 116 * The gray scale is defined in incremental way, with reference
 117 * to the length of previous table entry:
 118 * Setting of GS1 has to be >= 0
 119 * Setting of GS2 has to be > Setting of GS1 +1
 120 * Setting of GS3 has to be > Setting of GS2 +1
 121 * :
 122 * Setting of GS63 has to be > Setting of GS62 +1
 123 *
 124 */
 125static int set_gamma(struct fbtft_par *par, u32 *curves)
 126{
 127        unsigned long tmp[GAMMA_NUM * GAMMA_LEN];
 128        int i, acc = 0;
 129
 130        for (i = 0; i < 63; i++) {
 131                if (i > 0 && curves[i] < 2) {
 132                        dev_err(par->info->device,
 133                                "Illegal value in Grayscale Lookup Table at index %d. Must be greater than 1\n",
 134                                i);
 135                        return -EINVAL;
 136                }
 137                acc += curves[i];
 138                tmp[i] = acc;
 139                if (acc > 180) {
 140                        dev_err(par->info->device,
 141                                "Illegal value(s) in Grayscale Lookup Table. At index=%d, the accumulated value has exceeded 180\n",
 142                                i);
 143                        return -EINVAL;
 144                }
 145        }
 146
 147        write_reg(par, 0xB8,
 148                  tmp[0], tmp[1], tmp[2], tmp[3], tmp[4], tmp[5], tmp[6],
 149                  tmp[7], tmp[8], tmp[9], tmp[10], tmp[11], tmp[12], tmp[13],
 150                  tmp[14], tmp[15], tmp[16], tmp[17], tmp[18], tmp[19], tmp[20],
 151                  tmp[21], tmp[22], tmp[23], tmp[24], tmp[25], tmp[26], tmp[27],
 152                  tmp[28], tmp[29], tmp[30], tmp[31], tmp[32], tmp[33], tmp[34],
 153                  tmp[35], tmp[36], tmp[37], tmp[38], tmp[39], tmp[40], tmp[41],
 154                  tmp[42], tmp[43], tmp[44], tmp[45], tmp[46], tmp[47], tmp[48],
 155                  tmp[49], tmp[50], tmp[51], tmp[52], tmp[53], tmp[54], tmp[55],
 156                  tmp[56], tmp[57], tmp[58], tmp[59], tmp[60], tmp[61],
 157                  tmp[62]);
 158
 159        return 0;
 160}
 161
 162static int blank(struct fbtft_par *par, bool on)
 163{
 164        fbtft_par_dbg(DEBUG_BLANK, par, "%s(blank=%s)\n",
 165                      __func__, on ? "true" : "false");
 166        if (on)
 167                write_reg(par, 0xAE);
 168        else
 169                write_reg(par, 0xAF);
 170        return 0;
 171}
 172
 173static struct fbtft_display display = {
 174        .regwidth = 8,
 175        .width = WIDTH,
 176        .height = HEIGHT,
 177        .gamma_num = GAMMA_NUM,
 178        .gamma_len = GAMMA_LEN,
 179        .gamma = DEFAULT_GAMMA,
 180        .fbtftops = {
 181                .write_register = write_reg8_bus8,
 182                .init_display = init_display,
 183                .set_addr_win = set_addr_win,
 184                .set_gamma = set_gamma,
 185                .blank = blank,
 186        },
 187};
 188
 189FBTFT_REGISTER_DRIVER(DRVNAME, "solomon,ssd1331", &display);
 190
 191MODULE_ALIAS("spi:" DRVNAME);
 192MODULE_ALIAS("platform:" DRVNAME);
 193MODULE_ALIAS("spi:ssd1331");
 194MODULE_ALIAS("platform:ssd1331");
 195
 196MODULE_DESCRIPTION("SSD1331 OLED Driver");
 197MODULE_AUTHOR("Alec Smecher (adapted from SSD1351 by James Davies)");
 198MODULE_LICENSE("GPL");
 199