LXR linux/drivers/staging/fbtft/fb

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * FB driver for the ILI9325 LCD Controller
   4 *
   5 * Copyright (C) 2013 Noralf Tronnes
   6 *
   7 * Based on ili9325.c by Jeroen Domburg
   8 */
   9
  10#include <linux/module.h>
  11#include <linux/kernel.h>
  12#include <linux/init.h>
  13#include <linux/gpio/consumer.h>
  14#include <linux/delay.h>
  15
  16#include "fbtft.h"
  17
  18#define DRVNAME         "fb_ili9325"
  19#define WIDTH           240
  20#define HEIGHT          320
  21#define BPP             16
  22#define FPS             20
  23#define DEFAULT_GAMMA   "0F 00 7 2 0 0 6 5 4 1\n" \
  24                        "04 16 2 7 6 3 2 1 7 7"
  25
  26static unsigned int bt = 6; /* VGL=Vci*4 , VGH=Vci*4 */
  27module_param(bt, uint, 0000);
  28MODULE_PARM_DESC(bt, "Sets the factor used in the step-up circuits");
  29
  30static unsigned int vc = 0x03; /* Vci1=Vci*0.80 */
  31module_param(vc, uint, 0000);
  32MODULE_PARM_DESC(vc, "Sets the ratio factor of Vci to generate the reference voltages Vci1");
  33
  34static unsigned int vrh = 0x0d; /* VREG1OUT=Vci*1.85 */
  35module_param(vrh, uint, 0000);
  36MODULE_PARM_DESC(vrh, "Set the amplifying rate (1.6 ~ 1.9) of Vci applied to output the VREG1OUT");
  37
  38static unsigned int vdv = 0x12; /* VCOMH amplitude=VREG1OUT*0.98 */
  39module_param(vdv, uint, 0000);
  40MODULE_PARM_DESC(vdv, "Select the factor of VREG1OUT to set the amplitude of Vcom");
  41
  42static unsigned int vcm = 0x0a; /* VCOMH=VREG1OUT*0.735 */
  43module_param(vcm, uint, 0000);
  44MODULE_PARM_DESC(vcm, "Set the internal VcomH voltage");
  45
  46/*
  47 * Verify that this configuration is within the Voltage limits
  48 *
  49 * Display module configuration: Vcc = IOVcc = Vci = 3.3V
  50 *
  51 * Voltages
  52 * ----------
  53 * Vci                                =   3.3
  54 * Vci1           =  Vci * 0.80       =   2.64
  55 * DDVDH          =  Vci1 * 2         =   5.28
  56 * VCL            = -Vci1             =  -2.64
  57 * VREG1OUT       =  Vci * 1.85       =   4.88
  58 * VCOMH          =  VREG1OUT * 0.735 =   3.59
  59 * VCOM amplitude =  VREG1OUT * 0.98  =   4.79
  60 * VGH            =  Vci * 4          =  13.2
  61 * VGL            = -Vci * 4          = -13.2
  62 *
  63 * Limits
  64 * --------
  65 * Power supplies
  66 * 1.65 < IOVcc < 3.30   =>  1.65 < 3.3 < 3.30
  67 * 2.40 < Vcc   < 3.30   =>  2.40 < 3.3 < 3.30
  68 * 2.50 < Vci   < 3.30   =>  2.50 < 3.3 < 3.30
  69 *
  70 * Source/VCOM power supply voltage
  71 *  4.50 < DDVDH < 6.0   =>  4.50 <  5.28 <  6.0
  72 * -3.0  < VCL   < -2.0  =>  -3.0 < -2.64 < -2.0
  73 * VCI - VCL < 6.0       =>  5.94 < 6.0
  74 *
  75 * Gate driver output voltage
  76 *  10  < VGH   < 20     =>   10 <  13.2  < 20
  77 * -15  < VGL   < -5     =>  -15 < -13.2  < -5
  78 * VGH - VGL < 32        =>   26.4 < 32
  79 *
  80 * VCOM driver output voltage
  81 * VCOMH - VCOML < 6.0   =>  4.79 < 6.0
  82 */
  83
  84static int init_display(struct fbtft_par *par)
  85{
  86        par->fbtftops.reset(par);
  87
  88        if (par->gpio.cs)
  89                gpiod_set_value(par->gpio.cs, 0);  /* Activate chip */
  90
  91        bt &= 0x07;
  92        vc &= 0x07;
  93        vrh &= 0x0f;
  94        vdv &= 0x1f;
  95        vcm &= 0x3f;
  96
  97        /* Initialization sequence from ILI9325 Application Notes */
  98
  99        /* ----------- Start Initial Sequence ----------- */
 100        write_reg(par, 0x00E3, 0x3008); /* Set internal timing */
 101        write_reg(par, 0x00E7, 0x0012); /* Set internal timing */
 102        write_reg(par, 0x00EF, 0x1231); /* Set internal timing */
 103        write_reg(par, 0x0001, 0x0100); /* set SS and SM bit */
 104        write_reg(par, 0x0002, 0x0700); /* set 1 line inversion */
 105        write_reg(par, 0x0004, 0x0000); /* Resize register */
 106        write_reg(par, 0x0008, 0x0207); /* set the back porch and front porch */
 107        write_reg(par, 0x0009, 0x0000); /* set non-display area refresh cycle */
 108        write_reg(par, 0x000A, 0x0000); /* FMARK function */
 109        write_reg(par, 0x000C, 0x0000); /* RGB interface setting */
 110        write_reg(par, 0x000D, 0x0000); /* Frame marker Position */
 111        write_reg(par, 0x000F, 0x0000); /* RGB interface polarity */
 112
 113        /* ----------- Power On sequence ----------- */
 114        write_reg(par, 0x0010, 0x0000); /* SAP, BT[3:0], AP, DSTB, SLP, STB */
 115        write_reg(par, 0x0011, 0x0007); /* DC1[2:0], DC0[2:0], VC[2:0] */
 116        write_reg(par, 0x0012, 0x0000); /* VREG1OUT voltage */
 117        write_reg(par, 0x0013, 0x0000); /* VDV[4:0] for VCOM amplitude */
 118        mdelay(200); /* Dis-charge capacitor power voltage */
 119        write_reg(par, 0x0010, /* SAP, BT[3:0], AP, DSTB, SLP, STB */
 120                BIT(12) | (bt << 8) | BIT(7) | BIT(4));
 121        write_reg(par, 0x0011, 0x220 | vc); /* DC1[2:0], DC0[2:0], VC[2:0] */
 122        mdelay(50); /* Delay 50ms */
 123        write_reg(par, 0x0012, vrh); /* Internal reference voltage= Vci; */
 124        mdelay(50); /* Delay 50ms */
 125        write_reg(par, 0x0013, vdv << 8); /* Set VDV[4:0] for VCOM amplitude */
 126        write_reg(par, 0x0029, vcm); /* Set VCM[5:0] for VCOMH */
 127        write_reg(par, 0x002B, 0x000C); /* Set Frame Rate */
 128        mdelay(50); /* Delay 50ms */
 129        write_reg(par, 0x0020, 0x0000); /* GRAM horizontal Address */
 130        write_reg(par, 0x0021, 0x0000); /* GRAM Vertical Address */
 131
 132        /*------------------ Set GRAM area --------------- */
 133        write_reg(par, 0x0050, 0x0000); /* Horizontal GRAM Start Address */
 134        write_reg(par, 0x0051, 0x00EF); /* Horizontal GRAM End Address */
 135        write_reg(par, 0x0052, 0x0000); /* Vertical GRAM Start Address */
 136        write_reg(par, 0x0053, 0x013F); /* Vertical GRAM Start Address */
 137        write_reg(par, 0x0060, 0xA700); /* Gate Scan Line */
 138        write_reg(par, 0x0061, 0x0001); /* NDL,VLE, REV */
 139        write_reg(par, 0x006A, 0x0000); /* set scrolling line */
 140
 141        /*-------------- Partial Display Control --------- */
 142        write_reg(par, 0x0080, 0x0000);
 143        write_reg(par, 0x0081, 0x0000);
 144        write_reg(par, 0x0082, 0x0000);
 145        write_reg(par, 0x0083, 0x0000);
 146        write_reg(par, 0x0084, 0x0000);
 147        write_reg(par, 0x0085, 0x0000);
 148
 149        /*-------------- Panel Control ------------------- */
 150        write_reg(par, 0x0090, 0x0010);
 151        write_reg(par, 0x0092, 0x0600);
 152        write_reg(par, 0x0007, 0x0133); /* 262K color and display ON */
 153
 154        return 0;
 155}
 156
 157static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
 158{
 159        switch (par->info->var.rotate) {
 160        /* R20h = Horizontal GRAM Start Address */
 161        /* R21h = Vertical GRAM Start Address */
 162        case 0:
 163                write_reg(par, 0x0020, xs);
 164                write_reg(par, 0x0021, ys);
 165                break;
 166        case 180:
 167                write_reg(par, 0x0020, WIDTH - 1 - xs);
 168                write_reg(par, 0x0021, HEIGHT - 1 - ys);
 169                break;
 170        case 270:
 171                write_reg(par, 0x0020, WIDTH - 1 - ys);
 172                write_reg(par, 0x0021, xs);
 173                break;
 174        case 90:
 175                write_reg(par, 0x0020, ys);
 176                write_reg(par, 0x0021, HEIGHT - 1 - xs);
 177                break;
 178        }
 179        write_reg(par, 0x0022); /* Write Data to GRAM */
 180}
 181
 182static int set_var(struct fbtft_par *par)
 183{
 184        switch (par->info->var.rotate) {
 185        /* AM: GRAM update direction */
 186        case 0:
 187                write_reg(par, 0x03, 0x0030 | (par->bgr << 12));
 188                break;
 189        case 180:
 190                write_reg(par, 0x03, 0x0000 | (par->bgr << 12));
 191                break;
 192        case 270:
 193                write_reg(par, 0x03, 0x0028 | (par->bgr << 12));
 194                break;
 195        case 90:
 196                write_reg(par, 0x03, 0x0018 | (par->bgr << 12));
 197                break;
 198        }
 199
 200        return 0;
 201}
 202
 203/*
 204 * Gamma string format:
 205 *  VRP0 VRP1 RP0 RP1 KP0 KP1 KP2 KP3 KP4 KP5
 206 *  VRN0 VRN1 RN0 RN1 KN0 KN1 KN2 KN3 KN4 KN5
 207 */
 208#define CURVE(num, idx)  curves[(num) * par->gamma.num_values + (idx)]
 209static int set_gamma(struct fbtft_par *par, u32 *curves)
 210{
 211        unsigned long mask[] = {
 212                0x1f, 0x1f, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
 213                0x1f, 0x1f, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
 214        };
 215        int i, j;
 216
 217        /* apply mask */
 218        for (i = 0; i < 2; i++)
 219                for (j = 0; j < 10; j++)
 220                        CURVE(i, j) &= mask[i * par->gamma.num_values + j];
 221
 222        write_reg(par, 0x0030, CURVE(0, 5) << 8 | CURVE(0, 4));
 223        write_reg(par, 0x0031, CURVE(0, 7) << 8 | CURVE(0, 6));
 224        write_reg(par, 0x0032, CURVE(0, 9) << 8 | CURVE(0, 8));
 225        write_reg(par, 0x0035, CURVE(0, 3) << 8 | CURVE(0, 2));
 226        write_reg(par, 0x0036, CURVE(0, 1) << 8 | CURVE(0, 0));
 227
 228        write_reg(par, 0x0037, CURVE(1, 5) << 8 | CURVE(1, 4));
 229        write_reg(par, 0x0038, CURVE(1, 7) << 8 | CURVE(1, 6));
 230        write_reg(par, 0x0039, CURVE(1, 9) << 8 | CURVE(1, 8));
 231        write_reg(par, 0x003C, CURVE(1, 3) << 8 | CURVE(1, 2));
 232        write_reg(par, 0x003D, CURVE(1, 1) << 8 | CURVE(1, 0));
 233
 234        return 0;
 235}
 236
 237#undef CURVE
 238
 239static struct fbtft_display display = {
 240        .regwidth = 16,
 241        .width = WIDTH,
 242        .height = HEIGHT,
 243        .bpp = BPP,
 244        .fps = FPS,
 245        .gamma_num = 2,
 246        .gamma_len = 10,
 247        .gamma = DEFAULT_GAMMA,
 248        .fbtftops = {
 249                .init_display = init_display,
 250                .set_addr_win = set_addr_win,
 251                .set_var = set_var,
 252                .set_gamma = set_gamma,
 253        },
 254};
 255
 256FBTFT_REGISTER_DRIVER(DRVNAME, "ilitek,ili9325", &display);
 257
 258MODULE_ALIAS("spi:" DRVNAME);
 259MODULE_ALIAS("platform:" DRVNAME);
 260MODULE_ALIAS("spi:ili9325");
 261MODULE_ALIAS("platform:ili9325");
 262
 263MODULE_DESCRIPTION("FB driver for the ILI9325 LCD Controller");
 264MODULE_AUTHOR("Noralf Tronnes");
 265MODULE_LICENSE("GPL");
 266