/* * FB driver for the ILI9325 LCD Controller * * Copyright (C) 2013 Noralf Tronnes * * Based on ili9325.c by Jeroen Domburg * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/init.h> #include <linux/gpio.h> #include <linux/delay.h> #include "fbtft.h" #define DRVNAME "fb_ili9325" #define WIDTH 240 #define HEIGHT 320 #define BPP 16 #define FPS 20 #define DEFAULT_GAMMA "0F 00 7 2 0 0 6 5 4 1\n" \ "04 16 2 7 6 3 2 1 7 7" static unsigned bt = 6; /* VGL=Vci*4 , VGH=Vci*4 */ module_param(bt, uint, 0); MODULE_PARM_DESC(bt, "Sets the factor used in the step-up circuits"); static unsigned vc = 0x03; /* Vci1=Vci*0.80 */ module_param(vc, uint, 0); MODULE_PARM_DESC(vc, "Sets the ratio factor of Vci to generate the reference voltages Vci1"); static unsigned vrh = 0x0d; /* VREG1OUT=Vci*1.85 */ module_param(vrh, uint, 0); MODULE_PARM_DESC(vrh, "Set the amplifying rate (1.6 ~ 1.9) of Vci applied to output the VREG1OUT"); static unsigned vdv = 0x12; /* VCOMH amplitude=VREG1OUT*0.98 */ module_param(vdv, uint, 0); MODULE_PARM_DESC(vdv, "Select the factor of VREG1OUT to set the amplitude of Vcom"); static unsigned vcm = 0x0a; /* VCOMH=VREG1OUT*0.735 */ module_param(vcm, uint, 0); MODULE_PARM_DESC(vcm, "Set the internal VcomH voltage"); /* Verify that this configuration is within the Voltage limits Display module configuration: Vcc = IOVcc = Vci = 3.3V Voltages ---------- Vci = 3.3 Vci1 = Vci * 0.80 = 2.64 DDVDH = Vci1 * 2 = 5.28 VCL = -Vci1 = -2.64 VREG1OUT = Vci * 1.85 = 4.88 VCOMH = VREG1OUT * 0.735 = 3.59 VCOM amplitude = VREG1OUT * 0.98 = 4.79 VGH = Vci * 4 = 13.2 VGL = -Vci * 4 = -13.2 Limits -------- Power supplies 1.65 < IOVcc < 3.30 => 1.65 < 3.3 < 3.30 2.40 < Vcc < 3.30 => 2.40 < 3.3 < 3.30 2.50 < Vci < 3.30 => 2.50 < 3.3 < 3.30 Source/VCOM power supply voltage 4.50 < DDVDH < 6.0 => 4.50 < 5.28 < 6.0 -3.0 < VCL < -2.0 => -3.0 < -2.64 < -2.0 VCI - VCL < 6.0 => 5.94 < 6.0 Gate driver output voltage 10 < VGH < 20 => 10 < 13.2 < 20 -15 < VGL < -5 => -15 < -13.2 < -5 VGH - VGL < 32 => 26.4 < 32 VCOM driver output voltage VCOMH - VCOML < 6.0 => 4.79 < 6.0 */ static int init_display(struct fbtft_par *par) { fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); par->fbtftops.reset(par); if (par->gpio.cs != -1) gpio_set_value(par->gpio.cs, 0); /* Activate chip */ bt &= 0x07; vc &= 0x07; vrh &= 0x0f; vdv &= 0x1f; vcm &= 0x3f; /* Initialization sequence from ILI9325 Application Notes */ /* ----------- Start Initial Sequence ----------- */ write_reg(par, 0x00E3, 0x3008); /* Set internal timing */ write_reg(par, 0x00E7, 0x0012); /* Set internal timing */ write_reg(par, 0x00EF, 0x1231); /* Set internal timing */ write_reg(par, 0x0001, 0x0100); /* set SS and SM bit */ write_reg(par, 0x0002, 0x0700); /* set 1 line inversion */ write_reg(par, 0x0004, 0x0000); /* Resize register */ write_reg(par, 0x0008, 0x0207); /* set the back porch and front porch */ write_reg(par, 0x0009, 0x0000); /* set non-display area refresh cycle */ write_reg(par, 0x000A, 0x0000); /* FMARK function */ write_reg(par, 0x000C, 0x0000); /* RGB interface setting */ write_reg(par, 0x000D, 0x0000); /* Frame marker Position */ write_reg(par, 0x000F, 0x0000); /* RGB interface polarity */ /* ----------- Power On sequence ----------- */ write_reg(par, 0x0010, 0x0000); /* SAP, BT[3:0], AP, DSTB, SLP, STB */ write_reg(par, 0x0011, 0x0007); /* DC1[2:0], DC0[2:0], VC[2:0] */ write_reg(par, 0x0012, 0x0000); /* VREG1OUT voltage */ write_reg(par, 0x0013, 0x0000); /* VDV[4:0] for VCOM amplitude */ mdelay(200); /* Dis-charge capacitor power voltage */ write_reg(par, 0x0010, /* SAP, BT[3:0], AP, DSTB, SLP, STB */ (1 << 12) | (bt << 8) | (1 << 7) | (0x01 << 4)); write_reg(par, 0x0011, 0x220 | vc); /* DC1[2:0], DC0[2:0], VC[2:0] */ mdelay(50); /* Delay 50ms */ write_reg(par, 0x0012, vrh); /* Internal reference voltage= Vci; */ mdelay(50); /* Delay 50ms */ write_reg(par, 0x0013, vdv << 8); /* Set VDV[4:0] for VCOM amplitude */ write_reg(par, 0x0029, vcm); /* Set VCM[5:0] for VCOMH */ write_reg(par, 0x002B, 0x000C); /* Set Frame Rate */ mdelay(50); /* Delay 50ms */ write_reg(par, 0x0020, 0x0000); /* GRAM horizontal Address */ write_reg(par, 0x0021, 0x0000); /* GRAM Vertical Address */ /*------------------ Set GRAM area --------------- */ write_reg(par, 0x0050, 0x0000); /* Horizontal GRAM Start Address */ write_reg(par, 0x0051, 0x00EF); /* Horizontal GRAM End Address */ write_reg(par, 0x0052, 0x0000); /* Vertical GRAM Start Address */ write_reg(par, 0x0053, 0x013F); /* Vertical GRAM Start Address */ write_reg(par, 0x0060, 0xA700); /* Gate Scan Line */ write_reg(par, 0x0061, 0x0001); /* NDL,VLE, REV */ write_reg(par, 0x006A, 0x0000); /* set scrolling line */ /*-------------- Partial Display Control --------- */ write_reg(par, 0x0080, 0x0000); write_reg(par, 0x0081, 0x0000); write_reg(par, 0x0082, 0x0000); write_reg(par, 0x0083, 0x0000); write_reg(par, 0x0084, 0x0000); write_reg(par, 0x0085, 0x0000); /*-------------- Panel Control ------------------- */ write_reg(par, 0x0090, 0x0010); write_reg(par, 0x0092, 0x0600); write_reg(par, 0x0007, 0x0133); /* 262K color and display ON */ return 0; } static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye) { fbtft_par_dbg(DEBUG_SET_ADDR_WIN, par, "%s(xs=%d, ys=%d, xe=%d, ye=%d)\n", __func__, xs, ys, xe, ye); switch (par->info->var.rotate) { /* R20h = Horizontal GRAM Start Address */ /* R21h = Vertical GRAM Start Address */ case 0: write_reg(par, 0x0020, xs); write_reg(par, 0x0021, ys); break; case 180: write_reg(par, 0x0020, WIDTH - 1 - xs); write_reg(par, 0x0021, HEIGHT - 1 - ys); break; case 270: write_reg(par, 0x0020, WIDTH - 1 - ys); write_reg(par, 0x0021, xs); break; case 90: write_reg(par, 0x0020, ys); write_reg(par, 0x0021, HEIGHT - 1 - xs); break; } write_reg(par, 0x0022); /* Write Data to GRAM */ } static int set_var(struct fbtft_par *par) { fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); switch (par->info->var.rotate) { /* AM: GRAM update direction */ case 0: write_reg(par, 0x03, 0x0030 | (par->bgr << 12)); break; case 180: write_reg(par, 0x03, 0x0000 | (par->bgr << 12)); break; case 270: write_reg(par, 0x03, 0x0028 | (par->bgr << 12)); break; case 90: write_reg(par, 0x03, 0x0018 | (par->bgr << 12)); break; } return 0; } /* Gamma string format: VRP0 VRP1 RP0 RP1 KP0 KP1 KP2 KP3 KP4 KP5 VRN0 VRN1 RN0 RN1 KN0 KN1 KN2 KN3 KN4 KN5 */ #define CURVE(num, idx) curves[num*par->gamma.num_values + idx] static int set_gamma(struct fbtft_par *par, unsigned long *curves) { unsigned long mask[] = { 0x1f, 0x1f, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x1f, 0x1f, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, }; int i, j; fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); /* apply mask */ for (i = 0; i < 2; i++) for (j = 0; j < 10; j++) CURVE(i, j) &= mask[i*par->gamma.num_values + j]; write_reg(par, 0x0030, CURVE(0, 5) << 8 | CURVE(0, 4)); write_reg(par, 0x0031, CURVE(0, 7) << 8 | CURVE(0, 6)); write_reg(par, 0x0032, CURVE(0, 9) << 8 | CURVE(0, 8)); write_reg(par, 0x0035, CURVE(0, 3) << 8 | CURVE(0, 2)); write_reg(par, 0x0036, CURVE(0, 1) << 8 | CURVE(0, 0)); write_reg(par, 0x0037, CURVE(1, 5) << 8 | CURVE(1, 4)); write_reg(par, 0x0038, CURVE(1, 7) << 8 | CURVE(1, 6)); write_reg(par, 0x0039, CURVE(1, 9) << 8 | CURVE(1, 8)); write_reg(par, 0x003C, CURVE(1, 3) << 8 | CURVE(1, 2)); write_reg(par, 0x003D, CURVE(1, 1) << 8 | CURVE(1, 0)); return 0; } #undef CURVE static struct fbtft_display display = { .regwidth = 16, .width = WIDTH, .height = HEIGHT, .bpp = BPP, .fps = FPS, .gamma_num = 2, .gamma_len = 10, .gamma = DEFAULT_GAMMA, .fbtftops = { .init_display = init_display, .set_addr_win = set_addr_win, .set_var = set_var, .set_gamma = set_gamma, }, }; FBTFT_REGISTER_DRIVER(DRVNAME, "ilitek,ili9325", &display); MODULE_ALIAS("spi:" DRVNAME); MODULE_ALIAS("platform:" DRVNAME); MODULE_ALIAS("spi:ili9325"); MODULE_ALIAS("platform:ili9325"); MODULE_DESCRIPTION("FB driver for the ILI9325 LCD Controller"); MODULE_AUTHOR("Noralf Tronnes"); MODULE_LICENSE("GPL");