// SPDX-License-Identifier: GPL-2.0+
/*
* FB driver for the ILI9325 LCD Controller
*
* Copyright (C) 2013 Noralf Tronnes
*
* Based on ili9325.c by Jeroen Domburg
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.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 int bt = 6; /* VGL=Vci*4 , VGH=Vci*4 */
module_param(bt, uint, 0000);
MODULE_PARM_DESC(bt, "Sets the factor used in the step-up circuits");
static unsigned int vc = 0x03; /* Vci1=Vci*0.80 */
module_param(vc, uint, 0000);
MODULE_PARM_DESC(vc, "Sets the ratio factor of Vci to generate the reference voltages Vci1");
static unsigned int vrh = 0x0d; /* VREG1OUT=Vci*1.85 */
module_param(vrh, uint, 0000);
MODULE_PARM_DESC(vrh, "Set the amplifying rate (1.6 ~ 1.9) of Vci applied to output the VREG1OUT");
static unsigned int vdv = 0x12; /* VCOMH amplitude=VREG1OUT*0.98 */
module_param(vdv, uint, 0000);
MODULE_PARM_DESC(vdv, "Select the factor of VREG1OUT to set the amplitude of Vcom");
static unsigned int vcm = 0x0a; /* VCOMH=VREG1OUT*0.735 */
module_param(vcm, uint, 0000);
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)
{
par->fbtftops.reset(par);
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 */
BIT(12) | (bt << 8) | BIT(7) | BIT(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)
{
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)
{
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, u32 *curves)
{
static const 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;
/* 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");