// SPDX-License-Identifier: GPL-2.0+
/*
* FBTFT driver for the RA8875 LCD Controller
* Copyright by Pf@nne & NOTRO
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include "fbtft.h"
#define DRVNAME "fb_ra8875"
static int write_spi(struct fbtft_par *par, void *buf, size_t len)
{
struct spi_transfer t = {
.tx_buf = buf,
.len = len,
.speed_hz = 1000000,
};
struct spi_message m;
fbtft_par_dbg_hex(DEBUG_WRITE, par, par->info->device, u8, buf, len,
"%s(len=%zu): ", __func__, len);
if (!par->spi) {
dev_err(par->info->device,
"%s: par->spi is unexpectedly NULL\n", __func__);
return -1;
}
spi_message_init(&m);
spi_message_add_tail(&t, &m);
return spi_sync(par->spi, &m);
}
static int init_display(struct fbtft_par *par)
{
gpiod_set_value(par->gpio.dc, 1);
par->fbtftops.reset(par);
if ((par->info->var.xres == 320) && (par->info->var.yres == 240)) {
/* PLL clock frequency */
write_reg(par, 0x88, 0x0A);
write_reg(par, 0x89, 0x02);
mdelay(10);
/* color deep / MCU Interface */
write_reg(par, 0x10, 0x0C);
/* pixel clock period */
write_reg(par, 0x04, 0x03);
mdelay(1);
/* horizontal settings */
write_reg(par, 0x14, 0x27);
write_reg(par, 0x15, 0x00);
write_reg(par, 0x16, 0x05);
write_reg(par, 0x17, 0x04);
write_reg(par, 0x18, 0x03);
/* vertical settings */
write_reg(par, 0x19, 0xEF);
write_reg(par, 0x1A, 0x00);
write_reg(par, 0x1B, 0x05);
write_reg(par, 0x1C, 0x00);
write_reg(par, 0x1D, 0x0E);
write_reg(par, 0x1E, 0x00);
write_reg(par, 0x1F, 0x02);
} else if ((par->info->var.xres == 480) &&
(par->info->var.yres == 272)) {
/* PLL clock frequency */
write_reg(par, 0x88, 0x0A);
write_reg(par, 0x89, 0x02);
mdelay(10);
/* color deep / MCU Interface */
write_reg(par, 0x10, 0x0C);
/* pixel clock period */
write_reg(par, 0x04, 0x82);
mdelay(1);
/* horizontal settings */
write_reg(par, 0x14, 0x3B);
write_reg(par, 0x15, 0x00);
write_reg(par, 0x16, 0x01);
write_reg(par, 0x17, 0x00);
write_reg(par, 0x18, 0x05);
/* vertical settings */
write_reg(par, 0x19, 0x0F);
write_reg(par, 0x1A, 0x01);
write_reg(par, 0x1B, 0x02);
write_reg(par, 0x1C, 0x00);
write_reg(par, 0x1D, 0x07);
write_reg(par, 0x1E, 0x00);
write_reg(par, 0x1F, 0x09);
} else if ((par->info->var.xres == 640) &&
(par->info->var.yres == 480)) {
/* PLL clock frequency */
write_reg(par, 0x88, 0x0B);
write_reg(par, 0x89, 0x02);
mdelay(10);
/* color deep / MCU Interface */
write_reg(par, 0x10, 0x0C);
/* pixel clock period */
write_reg(par, 0x04, 0x01);
mdelay(1);
/* horizontal settings */
write_reg(par, 0x14, 0x4F);
write_reg(par, 0x15, 0x05);
write_reg(par, 0x16, 0x0F);
write_reg(par, 0x17, 0x01);
write_reg(par, 0x18, 0x00);
/* vertical settings */
write_reg(par, 0x19, 0xDF);
write_reg(par, 0x1A, 0x01);
write_reg(par, 0x1B, 0x0A);
write_reg(par, 0x1C, 0x00);
write_reg(par, 0x1D, 0x0E);
write_reg(par, 0x1E, 0x00);
write_reg(par, 0x1F, 0x01);
} else if ((par->info->var.xres == 800) &&
(par->info->var.yres == 480)) {
/* PLL clock frequency */
write_reg(par, 0x88, 0x0B);
write_reg(par, 0x89, 0x02);
mdelay(10);
/* color deep / MCU Interface */
write_reg(par, 0x10, 0x0C);
/* pixel clock period */
write_reg(par, 0x04, 0x81);
mdelay(1);
/* horizontal settings */
write_reg(par, 0x14, 0x63);
write_reg(par, 0x15, 0x03);
write_reg(par, 0x16, 0x03);
write_reg(par, 0x17, 0x02);
write_reg(par, 0x18, 0x00);
/* vertical settings */
write_reg(par, 0x19, 0xDF);
write_reg(par, 0x1A, 0x01);
write_reg(par, 0x1B, 0x14);
write_reg(par, 0x1C, 0x00);
write_reg(par, 0x1D, 0x06);
write_reg(par, 0x1E, 0x00);
write_reg(par, 0x1F, 0x01);
} else {
dev_err(par->info->device, "display size is not supported!!");
return -1;
}
/* PWM clock */
write_reg(par, 0x8a, 0x81);
write_reg(par, 0x8b, 0xFF);
mdelay(10);
/* Display ON */
write_reg(par, 0x01, 0x80);
mdelay(10);
return 0;
}
static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
{
/* Set_Active_Window */
write_reg(par, 0x30, xs & 0x00FF);
write_reg(par, 0x31, (xs & 0xFF00) >> 8);
write_reg(par, 0x32, ys & 0x00FF);
write_reg(par, 0x33, (ys & 0xFF00) >> 8);
write_reg(par, 0x34, (xs + xe) & 0x00FF);
write_reg(par, 0x35, ((xs + xe) & 0xFF00) >> 8);
write_reg(par, 0x36, (ys + ye) & 0x00FF);
write_reg(par, 0x37, ((ys + ye) & 0xFF00) >> 8);
/* Set_Memory_Write_Cursor */
write_reg(par, 0x46, xs & 0xff);
write_reg(par, 0x47, (xs >> 8) & 0x03);
write_reg(par, 0x48, ys & 0xff);
write_reg(par, 0x49, (ys >> 8) & 0x01);
write_reg(par, 0x02);
}
static void write_reg8_bus8(struct fbtft_par *par, int len, ...)
{
va_list args;
int i, ret;
u8 *buf = par->buf;
/* slow down spi-speed for writing registers */
par->fbtftops.write = write_spi;
if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) {
va_start(args, len);
for (i = 0; i < len; i++)
buf[i] = (u8)va_arg(args, unsigned int);
va_end(args);
fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device,
u8, buf, len, "%s: ", __func__);
}
va_start(args, len);
*buf++ = 0x80;
*buf = (u8)va_arg(args, unsigned int);
ret = par->fbtftops.write(par, par->buf, 2);
if (ret < 0) {
va_end(args);
dev_err(par->info->device, "write() failed and returned %dn",
ret);
return;
}
len--;
udelay(100);
if (len) {
buf = (u8 *)par->buf;
*buf++ = 0x00;
i = len;
while (i--)
*buf++ = (u8)va_arg(args, unsigned int);
ret = par->fbtftops.write(par, par->buf, len + 1);
if (ret < 0) {
va_end(args);
dev_err(par->info->device,
"write() failed and returned %dn", ret);
return;
}
}
va_end(args);
/* restore user spi-speed */
par->fbtftops.write = fbtft_write_spi;
udelay(100);
}
static int write_vmem16_bus8(struct fbtft_par *par, size_t offset, size_t len)
{
u16 *vmem16;
__be16 *txbuf16;
size_t remain;
size_t to_copy;
size_t tx_array_size;
int i;
int ret = 0;
size_t startbyte_size = 0;
fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s(offset=%zu, len=%zu)\n",
__func__, offset, len);
remain = len / 2;
vmem16 = (u16 *)(par->info->screen_buffer + offset);
tx_array_size = par->txbuf.len / 2;
txbuf16 = par->txbuf.buf + 1;
tx_array_size -= 2;
*(u8 *)(par->txbuf.buf) = 0x00;
startbyte_size = 1;
while (remain) {
to_copy = min(tx_array_size, remain);
dev_dbg(par->info->device, " to_copy=%zu, remain=%zu\n",
to_copy, remain - to_copy);
for (i = 0; i < to_copy; i++)
txbuf16[i] = cpu_to_be16(vmem16[i]);
vmem16 = vmem16 + to_copy;
ret = par->fbtftops.write(par, par->txbuf.buf,
startbyte_size + to_copy * 2);
if (ret < 0)
return ret;
remain -= to_copy;
}
return ret;
}
static struct fbtft_display display = {
.regwidth = 8,
.fbtftops = {
.init_display = init_display,
.set_addr_win = set_addr_win,
.write_register = write_reg8_bus8,
.write_vmem = write_vmem16_bus8,
.write = write_spi,
},
};
FBTFT_REGISTER_DRIVER(DRVNAME, "raio,ra8875", &display);
MODULE_ALIAS("spi:" DRVNAME);
MODULE_ALIAS("platform:" DRVNAME);
MODULE_ALIAS("spi:ra8875");
MODULE_ALIAS("platform:ra8875");
MODULE_DESCRIPTION("FB driver for the RA8875 LCD Controller");
MODULE_AUTHOR("Pf@nne");
MODULE_LICENSE("GPL");
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