drivers/staging/fbtft/fb_hx8340bn.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * FB driver for the HX8340BN LCD Controller
   4  *
   5  * This display uses 9-bit SPI: Data/Command bit + 8 data bits
   6  * For platforms that doesn't support 9-bit, the driver is capable
   7  * of emulating this using 8-bit transfer.
   8  * This is done by transferring eight 9-bit words in 9 bytes.
   9  *
  10  * Copyright (C) 2013 Noralf Tronnes
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/kernel.h>
  15 #include <linux/init.h>
  16 #include <linux/vmalloc.h>
  17 #include <linux/spi/spi.h>
  18 #include <linux/delay.h>
  19 #include <video/mipi_display.h>
  20
  21 #include "fbtft.h"
  22
  23 #define DRVNAME         "fb_hx8340bn"
  24 #define WIDTH           176
  25 #define HEIGHT          220
  26 #define TXBUFLEN        (4 * PAGE_SIZE)
  27 #define DEFAULT_GAMMA   "1 3 0E 5 0 2 09 0 6 1 7 1 0 2 2\n" \
  28                         "3 3 17 8 4 7 05 7 6 0 3 1 6 0 0 "
  29
  30 static bool emulate;
  31 module_param(emulate, bool, 0000);
  32 MODULE_PARM_DESC(emulate, "Force emulation in 9-bit mode");
  33
  34 static int init_display(struct fbtft_par *par)
  35 {
  36         par->fbtftops.reset(par);
  37
  38         /* BTL221722-276L startup sequence, from datasheet */
  39
  40         /*
  41          * SETEXTCOM: Set extended command set (C1h)
  42          * This command is used to set extended command set access enable.
  43          * Enable: After command (C1h), must write: ffh,83h,40h
  44          */
  45         write_reg(par, 0xC1, 0xFF, 0x83, 0x40);
  46
  47         /*
  48          * Sleep out
  49          * This command turns off sleep mode.
  50          * In this mode the DC/DC converter is enabled, Internal oscillator
  51          * is started, and panel scanning is started.
  52          */
  53         write_reg(par, 0x11);
  54         mdelay(150);
  55
  56         /* Undoc'd register? */
  57         write_reg(par, 0xCA, 0x70, 0x00, 0xD9);
  58
  59         /*
  60          * SETOSC: Set Internal Oscillator (B0h)
  61          * This command is used to set internal oscillator related settings
  62          *      OSC_EN: Enable internal oscillator
  63          *      Internal oscillator frequency: 125% x 2.52MHz
  64          */
  65         write_reg(par, 0xB0, 0x01, 0x11);
  66
  67         /* Drive ability setting */
  68         write_reg(par, 0xC9, 0x90, 0x49, 0x10, 0x28, 0x28, 0x10, 0x00, 0x06);
  69         mdelay(20);
  70
  71         /*
  72          * SETPWCTR5: Set Power Control 5(B5h)
  73          * This command is used to set VCOM Low and VCOM High Voltage
  74          * VCOMH 0110101 :  3.925
  75          * VCOML 0100000 : -1.700
  76          * 45h=69  VCOMH: "VMH" + 5d   VCOML: "VMH" + 5d
  77          */
  78         write_reg(par, 0xB5, 0x35, 0x20, 0x45);
  79
  80         /*
  81          * SETPWCTR4: Set Power Control 4(B4h)
  82          *      VRH[4:0]:       Specify the VREG1 voltage adjusting.
  83          *                      VREG1 voltage is for gamma voltage setting.
  84          *      BT[2:0]:        Switch the output factor of step-up circuit 2
  85          *                      for VGH and VGL voltage generation.
  86          */
  87         write_reg(par, 0xB4, 0x33, 0x25, 0x4C);
  88         mdelay(10);
  89
  90         /*
  91          * Interface Pixel Format (3Ah)
  92          * This command is used to define the format of RGB picture data,
  93          * which is to be transfer via the system and RGB interface.
  94          * RGB interface: 16 Bit/Pixel
  95          */
  96         write_reg(par, MIPI_DCS_SET_PIXEL_FORMAT, MIPI_DCS_PIXEL_FMT_16BIT);
  97
  98         /*
  99          * Display on (29h)
 100          * This command is used to recover from DISPLAY OFF mode.
 101          * Output from the Frame Memory is enabled.
 102          */
 103         write_reg(par, MIPI_DCS_SET_DISPLAY_ON);
 104         mdelay(10);
 105
 106         return 0;
 107 }
 108
 109 static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
 110 {
 111         write_reg(par, MIPI_DCS_SET_COLUMN_ADDRESS, 0x00, xs, 0x00, xe);
 112         write_reg(par, MIPI_DCS_SET_PAGE_ADDRESS, 0x00, ys, 0x00, ye);
 113         write_reg(par, MIPI_DCS_WRITE_MEMORY_START);
 114 }
 115
 116 static int set_var(struct fbtft_par *par)
 117 {
 118         /* MADCTL - Memory data access control */
 119         /* RGB/BGR can be set with H/W pin SRGB and MADCTL BGR bit */
 120 #define MY BIT(7)
 121 #define MX BIT(6)
 122 #define MV BIT(5)
 123         switch (par->info->var.rotate) {
 124         case 0:
 125                 write_reg(par, MIPI_DCS_SET_ADDRESS_MODE, par->bgr << 3);
 126                 break;
 127         case 270:
 128                 write_reg(par, MIPI_DCS_SET_ADDRESS_MODE,
 129                           MX | MV | (par->bgr << 3));
 130                 break;
 131         case 180:
 132                 write_reg(par, MIPI_DCS_SET_ADDRESS_MODE,
 133                           MX | MY | (par->bgr << 3));
 134                 break;
 135         case 90:
 136                 write_reg(par, MIPI_DCS_SET_ADDRESS_MODE,
 137                           MY | MV | (par->bgr << 3));
 138                 break;
 139         }
 140
 141         return 0;
 142 }
 143
 144 /*
 145  * Gamma Curve selection, GC (only GC0 can be customized):
 146  *   0 = 2.2, 1 = 1.8, 2 = 2.5, 3 = 1.0
 147  * Gamma string format:
 148  *   OP0 OP1 CP0 CP1 CP2 CP3 CP4 MP0 MP1 MP2 MP3 MP4 MP5 CGM0 CGM1
 149  *   ON0 ON1 CN0 CN1 CN2 CN3 CN4 MN0 MN1 MN2 MN3 MN4 MN5 XXXX  GC
 150  */
 151 #define CURVE(num, idx)  curves[(num) * par->gamma.num_values + (idx)]
 152 static int set_gamma(struct fbtft_par *par, u32 *curves)
 153 {
 154         static const unsigned long mask[] = {
 155                 0x0f, 0x0f, 0x1f, 0x0f, 0x0f, 0x0f, 0x1f, 0x07, 0x07, 0x07,
 156                 0x07, 0x07, 0x07, 0x03, 0x03, 0x0f, 0x0f, 0x1f, 0x0f, 0x0f,
 157                 0x0f, 0x1f, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x00, 0x00,
 158         };
 159         int i, j;
 160
 161         /* apply mask */
 162         for (i = 0; i < par->gamma.num_curves; i++)
 163                 for (j = 0; j < par->gamma.num_values; j++)
 164                         CURVE(i, j) &= mask[i * par->gamma.num_values + j];
 165
 166         /* Gamma Set (26h) */
 167         write_reg(par, MIPI_DCS_SET_GAMMA_CURVE, 1 << CURVE(1, 14));
 168
 169         if (CURVE(1, 14))
 170                 return 0; /* only GC0 can be customized */
 171
 172         write_reg(par, 0xC2,
 173                   (CURVE(0, 8) << 4) | CURVE(0, 7),
 174                   (CURVE(0, 10) << 4) | CURVE(0, 9),
 175                   (CURVE(0, 12) << 4) | CURVE(0, 11),
 176                   CURVE(0, 2),
 177                   (CURVE(0, 4) << 4) | CURVE(0, 3),
 178                   CURVE(0, 5),
 179                   CURVE(0, 6),
 180                   (CURVE(0, 1) << 4) | CURVE(0, 0),
 181                   (CURVE(0, 14) << 2) | CURVE(0, 13));
 182
 183         write_reg(par, 0xC3,
 184                   (CURVE(1, 8) << 4) | CURVE(1, 7),
 185                   (CURVE(1, 10) << 4) | CURVE(1, 9),
 186                   (CURVE(1, 12) << 4) | CURVE(1, 11),
 187                   CURVE(1, 2),
 188                   (CURVE(1, 4) << 4) | CURVE(1, 3),
 189                   CURVE(1, 5),
 190                   CURVE(1, 6),
 191                   (CURVE(1, 1) << 4) | CURVE(1, 0));
 192
 193         mdelay(10);
 194
 195         return 0;
 196 }
 197
 198 #undef CURVE
 199
 200 static struct fbtft_display display = {
 201         .regwidth = 8,
 202         .width = WIDTH,
 203         .height = HEIGHT,
 204         .txbuflen = TXBUFLEN,
 205         .gamma_num = 2,
 206         .gamma_len = 15,
 207         .gamma = DEFAULT_GAMMA,
 208         .fbtftops = {
 209                 .init_display = init_display,
 210                 .set_addr_win = set_addr_win,
 211                 .set_var = set_var,
 212                 .set_gamma = set_gamma,
 213         },
 214 };
 215
 216 FBTFT_REGISTER_DRIVER(DRVNAME, "himax,hx8340bn", &display);
 217
 218 MODULE_ALIAS("spi:" DRVNAME);
 219 MODULE_ALIAS("platform:" DRVNAME);
 220 MODULE_ALIAS("spi:hx8340bn");
 221 MODULE_ALIAS("platform:hx8340bn");
 222
 223 MODULE_DESCRIPTION("FB driver for the HX8340BN LCD Controller");
 224 MODULE_AUTHOR("Noralf Tronnes");
 225 MODULE_LICENSE("GPL");