TinyVision 配套 LCD 模组使用 ST7789V 作为主控，模组大小为1.4寸。
Linux 5.15 内核适配
驱动勾选
由于使用的是 SPI0，所以 TinyVision 的 LCD 模块并不支持使用MIPI-DBI进行驱动，这里我们使用普通的SPI模拟时序。
勾选 SPI 驱动
这里我们使用 SPI-NG 驱动，勾选 <*> SPI NG Driver Support for Allwinner SoCs
勾选 Linux FrameBuffer 驱动
前往如下地址，勾选驱动
Device Drivers --->
Graphics support --->
Frame buffer Devices --->
<*> Support for frame buffer devices
Console display driver support --->
[*] Framebuffer Console support
[*] Map the console to the primary display device
[*] Staging drivers --->
<*> Support for small TFT LCD display modules --->
<*> FB driver for the ST7789V LCD Controller
适配 FBTFT 的设备树接口
进入内核文件夹，找到 kernel/linux-5.15/drivers/staging/fbtft/fbtft-core.c
添加头文件
#include <linux/gpio.h>
#include <linux/of_gpio.h>
修改 fbtft_request_one_gpio 函数，如下
static int fbtft_request_one_gpio(struct fbtft_par *par,
const char *name, int index,
struct gpio_desc **gpiop)
{
struct device *dev = par->info->device;
struct device_node *node = dev->of_node;
int gpio, flags, ret = 0;
enum of_gpio_flags of_flags;
if (of_find_property(node, name, NULL)) {
gpio = of_get_named_gpio_flags(node, name, index, &of_flags);
if (gpio == -ENOENT)
return 0;
if (gpio == -EPROBE_DEFER)
return gpio;
if (gpio < 0) {
dev_err(dev,
"failed to get '%s' from DT\n", name);
return gpio;
}
flags = (of_flags & OF_GPIO_ACTIVE_LOW) ? GPIOF_OUT_INIT_LOW :
GPIOF_OUT_INIT_HIGH;
ret = devm_gpio_request_one(dev, gpio, flags,
dev->driver->name);
if (ret) {
dev_err(dev,
"gpio_request_one('%s'=%d) failed with %d\n",
name, gpio, ret);
return ret;
}
*gpiop = gpio_to_desc(gpio);
fbtft_par_dbg(DEBUG_REQUEST_GPIOS, par, "%s: '%s' = GPIO%d\n",
__func__, name, gpio);
}
return ret;
}
编写配套屏幕 ST7789v 驱动
进入内核文件夹，找到 kernel/linux-5.15/drivers/staging/fbtft/fb_st7789v.c 修改文件如下：
// SPDX-License-Identifier: GPL-2.0+
/*
* FB driver for the ST7789V LCD Controller
*
* Copyright (C) 2015 Dennis Menschel
*/
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/completion.h>
#include <linux/module.h>
#include <video/mipi_display.h>
#include "fbtft.h"
#define DRVNAME "fb_st7789v"
#define DEFAULT_GAMMA \
"70 2C 2E 15 10 09 48 33 53 0B 19 18 20 25\n" \
"70 2C 2E 15 10 09 48 33 53 0B 19 18 20 25"
#define HSD20_IPS_GAMMA \
"D0 05 0A 09 08 05 2E 44 45 0F 17 16 2B 33\n" \
"D0 05 0A 09 08 05 2E 43 45 0F 16 16 2B 33"
#define HSD20_IPS 1
/**
* enum st7789v_command - ST7789V display controller commands
*
* @PORCTRL: porch setting
* @GCTRL: gate control
* @VCOMS: VCOM setting
* @VDVVRHEN: VDV and VRH command enable
* @VRHS: VRH set
* @VDVS: VDV set
* @VCMOFSET: VCOM offset set
* @PWCTRL1: power control 1
* @PVGAMCTRL: positive voltage gamma control
* @NVGAMCTRL: negative voltage gamma control
*
* The command names are the same as those found in the datasheet to ease
* looking up their semantics and usage.
*
* Note that the ST7789V display controller offers quite a few more commands
* which have been omitted from this list as they are not used at the moment.
* Furthermore, commands that are compliant with the MIPI DCS have been left
* out as well to avoid duplicate entries.
*/
enum st7789v_command {
PORCTRL = 0xB2,
GCTRL = 0xB7,
VCOMS = 0xBB,
VDVVRHEN = 0xC2,
VRHS = 0xC3,
VDVS = 0xC4,
VCMOFSET = 0xC5,
PWCTRL1 = 0xD0,
PVGAMCTRL = 0xE0,
NVGAMCTRL = 0xE1,
};
#define MADCTL_BGR BIT(3) /* bitmask for RGB/BGR order */
#define MADCTL_MV BIT(5) /* bitmask for page/column order */
#define MADCTL_MX BIT(6) /* bitmask for column address order */
#define MADCTL_MY BIT(7) /* bitmask for page address order */
/* 60Hz for 16.6ms, configured as 2*16.6ms */
#define PANEL_TE_TIMEOUT_MS 33
static struct completion panel_te; /* completion for panel TE line */
static int irq_te; /* Linux IRQ for LCD TE line */
static irqreturn_t panel_te_handler(int irq, void *data)
{
complete(&panel_te);
return IRQ_HANDLED;
}
/**
* init_display() - initialize the display controller
*
* @par: FBTFT parameter object
*
* Most of the commands in this init function set their parameters to the
* same default values which are already in place after the display has been
* powered up. (The main exception to this rule is the pixel format which
* would default to 18 instead of 16 bit per pixel.)
* Nonetheless, this sequence can be used as a template for concrete
* displays which usually need some adjustments.
*
* Return: 0 on success, < 0 if error occurred.
*/
static int init_display(struct fbtft_par *par)
{
par->fbtftops.reset(par);
mdelay(50);
write_reg(par,0x36,0x00);
write_reg(par,0x3A,0x05);
write_reg(par,0xB2,0x1F,0x1F,0x00,0x33,0x33);
write_reg(par,0xB7,0x35);
write_reg(par,0xBB,0x20);
write_reg(par,0xC0,0x2C);
write_reg(par,0xC2,0x01);
write_reg(par,0xC3,0x01);
write_reg(par,0xC4,0x18);
write_reg(par,0xC6,0x13);
write_reg(par,0xD0,0xA4,0xA1);
write_reg(par,0xE0,0xF0,0x04,0x07,0x04,0x04,0x04,0x25,0x33,0x3C,0x36,0x14,0x12,0x29,0x30);
write_reg(par,0xE1,0xF0,0x02,0x04,0x05,0x05,0x21,0x25,0x32,0x3B,0x38,0x12,0x14,0x27,0x31);
write_reg(par,0xE4,0x1D,0x00,0x00);
write_reg(par,0x21);
write_reg(par,0x11);
mdelay(50);
write_reg(par,0x29);
mdelay(200);
return 0;
}
/*
* write_vmem() - write data to display.
* @par: FBTFT parameter object.
* @offset: offset from screen_buffer.
* @len: the length of data to be writte.
*
* Return: 0 on success, or a negative error code otherwise.
*/
static int write_vmem(struct fbtft_par *par, size_t offset, size_t len)
{
struct device *dev = par->info->device;
int ret;
if (irq_te) {
enable_irq(irq_te);
reinit_completion(&panel_te);
ret = wait_for_completion_timeout(&panel_te,
msecs_to_jiffies(PANEL_TE_TIMEOUT_MS));
if (ret == 0)
dev_err(dev, "wait panel TE timeout\n");
disable_irq(irq_te);
}
switch (par->pdata->display.buswidth) {
case 8:
ret = fbtft_write_vmem16_bus8(par, offset, len);
break;
case 9:
ret = fbtft_write_vmem16_bus9(par, offset, len);
break;
case 16:
ret = fbtft_write_vmem16_bus16(par, offset, len);
break;
default:
dev_err(dev, "Unsupported buswidth %d\n",
par->pdata->display.buswidth);
ret = 0;
break;
}
return ret;
}
/**
* set_var() - apply LCD properties like rotation and BGR mode
*
* @par: FBTFT parameter object
*
* Return: 0 on success, < 0 if error occurred.
*/
static int set_var(struct fbtft_par *par)
{
u8 madctl_par = 0;
if (par->bgr)
madctl_par |= MADCTL_BGR;
switch (par->info->var.rotate) {
case 0:
break;
case 90:
madctl_par |= (MADCTL_MV | MADCTL_MY);
break;
case 180:
madctl_par |= (MADCTL_MX | MADCTL_MY);
break;
case 270:
madctl_par |= (MADCTL_MV | MADCTL_MX);
break;
default:
return -EINVAL;
}
write_reg(par, MIPI_DCS_SET_ADDRESS_MODE, madctl_par);
return 0;
}
/**
* set_gamma() - set gamma curves
*
* @par: FBTFT parameter object
* @curves: gamma curves
*
* Before the gamma curves are applied, they are preprocessed with a bitmask
* to ensure syntactically correct input for the display controller.
* This implies that the curves input parameter might be changed by this
* function and that illegal gamma values are auto-corrected and not
* reported as errors.
*
* Return: 0 on success, < 0 if error occurred.
*/
static int set_gamma(struct fbtft_par *par, u32 *curves)
{
int i;
int j;
int c; /* curve index offset */
/*
* Bitmasks for gamma curve command parameters.
* The masks are the same for both positive and negative voltage
* gamma curves.
*/
static const u8 gamma_par_mask[] = {
0xFF, /* V63[3:0], V0[3:0]*/
0x3F, /* V1[5:0] */
0x3F, /* V2[5:0] */
0x1F, /* V4[4:0] */
0x1F, /* V6[4:0] */
0x3F, /* J0[1:0], V13[3:0] */
0x7F, /* V20[6:0] */
0x77, /* V36[2:0], V27[2:0] */
0x7F, /* V43[6:0] */
0x3F, /* J1[1:0], V50[3:0] */
0x1F, /* V57[4:0] */
0x1F, /* V59[4:0] */
0x3F, /* V61[5:0] */
0x3F, /* V62[5:0] */
};
for (i = 0; i < par->gamma.num_curves; i++) {
c = i * par->gamma.num_values;
for (j = 0; j < par->gamma.num_values; j++)
curves[c + j] &= gamma_par_mask[j];
write_reg(par, PVGAMCTRL + i,
curves[c + 0], curves[c + 1], curves[c + 2],
curves[c + 3], curves[c + 4], curves[c + 5],
curves[c + 6], curves[c + 7], curves[c + 8],
curves[c + 9], curves[c + 10], curves[c + 11],
curves[c + 12], curves[c + 13]);
}
return 0;
}
/**
* blank() - blank the display
*
* @par: FBTFT parameter object
* @on: whether to enable or disable blanking the display
*
* Return: 0 on success, < 0 if error occurred.
*/
static int blank(struct fbtft_par *par, bool on)
{
if (on)
write_reg(par, MIPI_DCS_SET_DISPLAY_OFF);
else
write_reg(par, MIPI_DCS_SET_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)
{
case 0:
break;
case 90:
xs+=80;xe+=80;
break;
case 180:
break;
case 270:
xs+=80;xe+=80;
break;
default :
break;
}
write_reg(par, MIPI_DCS_SET_COLUMN_ADDRESS,
(xs >> 8) & 0xFF, xs & 0xFF, (xe >> 8) & 0xFF, xe & 0xFF);
write_reg(par, MIPI_DCS_SET_PAGE_ADDRESS,
(ys >> 8) & 0xFF, ys & 0xFF, (ye >> 8) & 0xFF, ye & 0xFF);
write_reg(par, MIPI_DCS_WRITE_MEMORY_START);
}
static void reset(struct fbtft_par *par)
{
if (!par->gpio.reset)
return;
gpiod_set_value_cansleep(par->gpio.reset, 1);
msleep(10);
gpiod_set_value_cansleep(par->gpio.reset, 0);
msleep(200);
gpiod_set_value_cansleep(par->gpio.reset, 1);
msleep(10);
gpiod_set_value_cansleep(par->gpio.cs, 1); /* Activate chip */
}
static struct fbtft_display display = {
.regwidth = 8,
.width = 240,
.height = 240,
.gamma_num = 2,
.gamma_len = 14,
.gamma = HSD20_IPS_GAMMA,
.fbtftops = {
.init_display = init_display,
.set_addr_win = set_addr_win,
.write_vmem = write_vmem,
.set_var = set_var,
.set_gamma = set_gamma,
.blank = blank,
.reset = reset,
},
};
FBTFT_REGISTER_DRIVER(DRVNAME, "sitronix,st7789v", &display);
MODULE_ALIAS("spi:" DRVNAME);
MODULE_ALIAS("platform:" DRVNAME);
MODULE_ALIAS("spi:st7789v");
MODULE_ALIAS("platform:st7789v");
MODULE_DESCRIPTION("FB driver for the ST7789V LCD Controller");
MODULE_AUTHOR("Dennis Menschel");
MODULE_LICENSE("GPL");
编写设备树
&pio {
spi0_pins_default: spi0@0 {
pins = "PC0", "PC2", "PC3"; /* clk, mosi, miso */
function = "spi0";
drive-strength = <10>;
};
spi0_pins_cs: spi0@1 {
pins = "PC1", "PC4", "PC5"; /* cs, wp, hold */
function = "spi0";
drive-strength = <10>;
bias-pull-up;
};
spi0_pins_lcd: spi0@2 {
pins = "PC0", "PC2"; /* clk, mosi */
function = "spi0";
drive-strength = <10>;
};
spi0_pins_lcd_cs: spi0@3 {
pins = "PC1"; /* cs */
function = "spi0";
drive-strength = <10>;
};
spi0_pins_sleep: spi0@4 {
pins = "PC0", "PC2", "PC3", "PC1", "PC4", "PC5";
function = "gpio_in";
drive-strength = <10>;
};
};
&spi0 {
pinctrl-0 = <&spi0_pins_lcd &spi0_pins_lcd_cs>;
pinctrl-1 = <&spi0_pins_sleep>;
pinctrl-names = "default", "sleep";
sunxi,spi-bus-mode = <SUNXI_SPI_BUS_MASTER>;
sunxi,spi-cs-mode = <SUNXI_SPI_CS_AUTO>;
status = "okay";
st7789v@0 {
status = "okay";
compatible = "sitronix,st7789v";
reg = <0>;
spi-max-frequency = <30000000>;
rotate = <0>;
bgr;
fps = <30>;
buswidth = <8>;
reset = <&pio PC 5 GPIO_ACTIVE_LOW>;
dc = <&pio PC 4 GPIO_ACTIVE_LOW>;
debug = <1>;
};
};
Linux 4.9 内核适配
驱动勾选
由于使用的是 SPI0，所以 TinyVision 的 LCD 模块并不支持使用MIPI-DBI进行驱动，这里我们使用普通的SPI模拟时序。
勾选 SPI 驱动
这里我们使用 SPI-NG 驱动，勾选 <*> SPI NG Driver Support for Allwinner SoCs
勾选 Linux FrameBuffer 驱动
前往如下地址，勾选驱动
Device Drivers --->
Graphics support --->
Frame buffer Devices --->
<*> Support for frame buffer devices
Console display driver support --->
[*] Framebuffer Console support
[*] Map the console to the primary display device
[*] Staging drivers --->
<*> Support for small TFT LCD display modules --->
<*> FB driver for the ST7789V LCD Controller
适配 FBTFT 的设备树接口
进入内核文件夹，找到 lichee/linux-4.9/drivers/staging/fbtft/fbtft-core.c
添加头文件
#include <linux/sunxi-gpio.h>
修改驱动注册接口
static int fbtft_request_one_gpio(struct fbtft_par *par,
const char *name, int index, int *gpiop)
{
struct device *dev = par->info->device;
struct device_node *node = dev->of_node;
int gpio, flags, ret = 0;
struct gpio_config gpio_of_flags;
if (of_find_property(node, name, NULL)) {
gpio = of_get_named_gpio_flags(node, name, index, (enum of_gpio_flags *)&gpio_of_flags);
if (gpio == -ENOENT)
return 0;
if (gpio == -EPROBE_DEFER)
return gpio;
if (gpio < 0) {
dev_err(dev,
"failed to get '%s' from DT\n", name);
return gpio;
}
/* active low translates to initially low */
flags = (gpio_of_flags.data & OF_GPIO_ACTIVE_LOW) ? GPIOF_OUT_INIT_LOW :
GPIOF_OUT_INIT_HIGH;
ret = devm_gpio_request_one(dev, gpio, flags,
dev->driver->name);
if (ret) {
dev_err(dev,
"gpio_request_one('%s'=%d) failed with %d\n",
name, gpio, ret);
return ret;
}
if (gpiop)
*gpiop = gpio;
fbtft_par_dbg(DEBUG_REQUEST_GPIOS, par, "%s: '%s' = GPIO%d\n",
__func__, name, gpio);
}
return ret;
}
static int fbtft_request_gpios_dt(struct fbtft_par *par)
{
int i;
int ret;
if (!par->info->device->of_node)
return -EINVAL;
ret = fbtft_request_one_gpio(par, "reset", 0, &par->gpio.reset);
if (ret)
return ret;
ret = fbtft_request_one_gpio(par, "dc", 0, &par->gpio.dc);
if (ret)
return ret;
ret = fbtft_request_one_gpio(par, "rd", 0, &par->gpio.rd);
if (ret)
return ret;
ret = fbtft_request_one_gpio(par, "wr", 0, &par->gpio.wr);
if (ret)
return ret;
ret = fbtft_request_one_gpio(par, "cs", 0, &par->gpio.cs);
if (ret)
return ret;
ret = fbtft_request_one_gpio(par, "latch", 0, &par->gpio.latch);
if (ret)
return ret;
for (i = 0; i < 16; i++) {
ret = fbtft_request_one_gpio(par, "db", i,
&par->gpio.db[i]);
if (ret)
return ret;
ret = fbtft_request_one_gpio(par, "led", i,
&par->gpio.led[i]);
if (ret)
return ret;
ret = fbtft_request_one_gpio(par, "aux", i,
&par->gpio.aux[i]);
if (ret)
return ret;
}
return 0;
}
编写配套屏幕 ST7789v 驱动
/*
* FB driver for the ST7789V LCD Controller
*
* Copyright (C) 2015 Dennis Menschel
*
* 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.
*/
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/gpio.h>
#include <video/mipi_display.h>
#include "fbtft.h"
#define DRVNAME "fb_st7789v"
#define DEFAULT_GAMMA \
"70 2C 2E 15 10 09 48 33 53 0B 19 18 20 25\n" \
"70 2C 2E 15 10 09 48 33 53 0B 19 18 20 25"
#define HSD20_IPS_GAMMA \
"D0 05 0A 09 08 05 2E 44 45 0F 17 16 2B 33\n" \
"D0 05 0A 09 08 05 2E 43 45 0F 16 16 2B 33"
/**
* enum st7789v_command - ST7789V display controller commands
*
* @PORCTRL: porch setting
* @GCTRL: gate control
* @VCOMS: VCOM setting
* @VDVVRHEN: VDV and VRH command enable
* @VRHS: VRH set
* @VDVS: VDV set
* @VCMOFSET: VCOM offset set
* @PWCTRL1: power control 1
* @PVGAMCTRL: positive voltage gamma control
* @NVGAMCTRL: negative voltage gamma control
*
* The command names are the same as those found in the datasheet to ease
* looking up their semantics and usage.
*
* Note that the ST7789V display controller offers quite a few more commands
* which have been omitted from this list as they are not used at the moment.
* Furthermore, commands that are compliant with the MIPI DCS have been left
* out as well to avoid duplicate entries.
*/
enum st7789v_command {
PORCTRL = 0xB2,
GCTRL = 0xB7,
VCOMS = 0xBB,
VDVVRHEN = 0xC2,
VRHS = 0xC3,
VDVS = 0xC4,
VCMOFSET = 0xC5,
PWCTRL1 = 0xD0,
PVGAMCTRL = 0xE0,
NVGAMCTRL = 0xE1,
};
#define MADCTL_BGR BIT(3) /* bitmask for RGB/BGR order */
#define MADCTL_MV BIT(5) /* bitmask for page/column order */
#define MADCTL_MX BIT(6) /* bitmask for column address order */
#define MADCTL_MY BIT(7) /* bitmask for page address order */
/**
* init_display() - initialize the display controller
*
* @par: FBTFT parameter object
*
* Most of the commands in this init function set their parameters to the
* same default values which are already in place after the display has been
* powered up. (The main exception to this rule is the pixel format which
* would default to 18 instead of 16 bit per pixel.)
* Nonetheless, this sequence can be used as a template for concrete
* displays which usually need some adjustments.
*
* Return: 0 on success, < 0 if error occurred.
*/
static int init_display(struct fbtft_par *par)
{
par->fbtftops.reset(par);
mdelay(50);
write_reg(par,0x36,0x00);
write_reg(par,0x3A,0x05);
write_reg(par,0xB2,0x1F,0x1F,0x00,0x33,0x33);
write_reg(par,0xB7,0x35);
write_reg(par,0xBB,0x20);
write_reg(par,0xC0,0x2C);
write_reg(par,0xC2,0x01);
write_reg(par,0xC3,0x01);
write_reg(par,0xC4,0x18);
write_reg(par,0xC6,0x13);
write_reg(par,0xD0,0xA4,0xA1);
write_reg(par,0xE0,0xF0,0x04,0x07,0x04,0x04,0x04,0x25,0x33,0x3C,0x36,0x14,0x12,0x29,0x30);
write_reg(par,0xE1,0xF0,0x02,0x04,0x05,0x05,0x21,0x25,0x32,0x3B,0x38,0x12,0x14,0x27,0x31);
write_reg(par,0xE4,0x1D,0x00,0x00);
write_reg(par,0x21);
write_reg(par,0x11);
mdelay(50);
write_reg(par,0x29);
mdelay(200);
return 0;
return 0;
}
/**
* set_var() - apply LCD properties like rotation and BGR mode
*
* @par: FBTFT parameter object
*
* Return: 0 on success, < 0 if error occurred.
*/
static int set_var(struct fbtft_par *par)
{
u8 madctl_par = 0;
if (par->bgr)
madctl_par |= MADCTL_BGR;
switch (par->info->var.rotate) {
case 0:
break;
case 90:
madctl_par |= (MADCTL_MV | MADCTL_MY);
break;
case 180:
madctl_par |= (MADCTL_MX | MADCTL_MY);
break;
case 270:
madctl_par |= (MADCTL_MV | MADCTL_MX);
break;
default:
return -EINVAL;
}
write_reg(par, MIPI_DCS_SET_ADDRESS_MODE, madctl_par);
return 0;
}
/**
* set_gamma() - set gamma curves
*
* @par: FBTFT parameter object
* @curves: gamma curves
*
* Before the gamma curves are applied, they are preprocessed with a bitmask
* to ensure syntactically correct input for the display controller.
* This implies that the curves input parameter might be changed by this
* function and that illegal gamma values are auto-corrected and not
* reported as errors.
*
* Return: 0 on success, < 0 if error occurred.
*/
static int set_gamma(struct fbtft_par *par, unsigned long *curves)
{
int i;
int j;
int c; /* curve index offset */
/*
* Bitmasks for gamma curve command parameters.
* The masks are the same for both positive and negative voltage
* gamma curves.
*/
const u8 gamma_par_mask[] = {
0xFF, /* V63[3:0], V0[3:0]*/
0x3F, /* V1[5:0] */
0x3F, /* V2[5:0] */
0x1F, /* V4[4:0] */
0x1F, /* V6[4:0] */
0x3F, /* J0[1:0], V13[3:0] */
0x7F, /* V20[6:0] */
0x77, /* V36[2:0], V27[2:0] */
0x7F, /* V43[6:0] */
0x3F, /* J1[1:0], V50[3:0] */
0x1F, /* V57[4:0] */
0x1F, /* V59[4:0] */
0x3F, /* V61[5:0] */
0x3F, /* V62[5:0] */
};
for (i = 0; i < par->gamma.num_curves; i++) {
c = i * par->gamma.num_values;
for (j = 0; j < par->gamma.num_values; j++)
curves[c + j] &= gamma_par_mask[j];
write_reg(
par, PVGAMCTRL + i,
curves[c + 0], curves[c + 1], curves[c + 2],
curves[c + 3], curves[c + 4], curves[c + 5],
curves[c + 6], curves[c + 7], curves[c + 8],
curves[c + 9], curves[c + 10], curves[c + 11],
curves[c + 12], curves[c + 13]);
}
return 0;
}
/**
* blank() - blank the display
*
* @par: FBTFT parameter object
* @on: whether to enable or disable blanking the display
*
* Return: 0 on success, < 0 if error occurred.
*/
static int blank(struct fbtft_par *par, bool on)
{
if (on)
write_reg(par, MIPI_DCS_SET_DISPLAY_OFF);
else
write_reg(par, MIPI_DCS_SET_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)
{
case 0:
break;
case 90:
xs+=80;xe+=80;
break;
case 180:
break;
case 270:
xs+=80;xe+=80;
break;
default :
break;
}
write_reg(par, MIPI_DCS_SET_COLUMN_ADDRESS,
(xs >> 8) & 0xFF, xs & 0xFF, (xe >> 8) & 0xFF, xe & 0xFF);
write_reg(par, MIPI_DCS_SET_PAGE_ADDRESS,
(ys >> 8) & 0xFF, ys & 0xFF, (ye >> 8) & 0xFF, ye & 0xFF);
write_reg(par, MIPI_DCS_WRITE_MEMORY_START);
}
static void reset(struct fbtft_par *par)
{
if (par->gpio.reset == -1)
return;
fbtft_par_dbg(DEBUG_RESET, par, "%s()\n", __func__);
gpio_set_value(par->gpio.reset, 1);
mdelay(20);
gpio_set_value(par->gpio.reset, 0);
mdelay(20);
gpio_set_value(par->gpio.reset, 1);
mdelay(120);
}
static struct fbtft_display display = {
.regwidth = 8,
.width = 240,
.height = 240,
.gamma_num = 2,
.gamma_len = 14,
.gamma = HSD20_IPS_GAMMA,
.fbtftops = {
.init_display = init_display,
.set_addr_win = set_addr_win,
.set_var = set_var,
.set_gamma = set_gamma,
.blank = blank,
.reset = reset,
},
};
FBTFT_REGISTER_DRIVER(DRVNAME, "sitronix,st7789v", &display);
MODULE_ALIAS("spi:" DRVNAME);
MODULE_ALIAS("platform:" DRVNAME);
MODULE_ALIAS("spi:st7789v");
MODULE_ALIAS("platform:st7789v");
MODULE_DESCRIPTION("FB driver for the ST7789V LCD Controller");
MODULE_AUTHOR("Dennis Menschel");
MODULE_LICENSE("GPL");
编写设备树
&pio {
spi0_pins_a: spi0@0 {
allwinner,pins = "PC0", "PC2", "PC3";
allwinner,pname = "spi0_sclk", "spi0_mosi", "spi0_miso";
allwinner,function = "spi0";
allwinner,muxsel = <4>;
allwinner,drive = <1>;
allwinner,pull = <0>;
};
spi0_pins_b: spi0@1 {
allwinner,pins = "PC1", "PC5", "PC4";
allwinner,pname = "spi0_cs0", "spi0_hold", "spi0_wp";
allwinner,function = "spi0";
allwinner,muxsel = <4>;
allwinner,drive = <1>;
allwinner,pull = <1>; // only CS should be pulled up
};
spi0_pins_c: spi0@2 {
allwinner,pins = "PC0", "PC1", "PC2", "PC3", "PC4", "PC5";
allwinner,function = "io_disabled";
allwinner,muxsel = <7>;
allwinner,drive = <1>;
allwinner,pull = <0>;
};
spi0_pins_lcd: spi0@3 {
allwinner,pins = "PC0", "PC2"; /* clk, mosi */
allwinner,function = "spi0";
allwinner,muxsel = <4>;
allwinner,drive = <1>;
allwinner,pull = <0>;
};
spi0_pins_lcd_cs: spi0@4 {
allwinner,pins = "PC1"; /* cs */
allwinner,function = "spi0";
allwinner,muxsel = <4>;
allwinner,pull = <1>;
allwinner,drive = <1>;
};
};
&spi0 {
clock-frequency = <100000000>;
pinctrl-0 = <&spi0_pins_lcd &spi0_pins_lcd_cs>;
pinctrl-1 = <&spi0_pins_c>;
pinctrl-names = "default", "sleep";
spi_slave_mode = <0>;
spi_dbi_enable = <0>;
spi0_cs_number = <1>;
status = "okay";
st7789v@0 {
status = "okay";
compatible = "sitronix,st7789v";
reg = <0>;
spi-max-frequency = <30000000>;
rotate = <0>;
bgr;
fps = <30>;
buswidth = <8>;
reset = <&pio PC 5 1 1 2 1>;
dc = <&pio PC 4 1 1 2 0>;
debug = <1>;
};
};
显示 Linux 终端
前往驱动勾选如下选项
Device Drivers --->
Graphics support --->
Frame buffer Devices --->
<*> Support for frame buffer devices
Console display driver support --->
[*] Framebuffer Console support
[*] Map the console to the primary display device
然后在 bootargs 添加一行 console=tty0 即可显示。
