// SPDX-License-Identifier: GPL-2.0+
/*
* DRM driver for Ilitek ILI9486 panels
*
* Copyright 2020 Kamlesh Gurudasani <[email protected]>
*/
#include <linux/backlight.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/property.h>
#include <linux/spi/spi.h>
#include <video/mipi_display.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_drv.h>
#include <drm/drm_fbdev_dma.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_gem_dma_helper.h>
#include <drm/drm_managed.h>
#include <drm/drm_mipi_dbi.h>
#include <drm/drm_modeset_helper.h>
#define ILI9486_ITFCTR1 0xb0
#define ILI9486_PWCTRL1 0xc2
#define ILI9486_VMCTRL1 0xc5
#define ILI9486_PGAMCTRL 0xe0
#define ILI9486_NGAMCTRL 0xe1
#define ILI9486_DGAMCTRL 0xe2
#define ILI9486_MADCTL_BGR BIT(3)
#define ILI9486_MADCTL_MV BIT(5)
#define ILI9486_MADCTL_MX BIT(6)
#define ILI9486_MADCTL_MY BIT(7)
/*
* The PiScreen/waveshare rpi-lcd-35 has a SPI to 16-bit parallel bus converter
* in front of the display controller. This means that 8-bit values have to be
* transferred as 16-bit.
*/
static int waveshare_command(struct mipi_dbi *mipi, u8 *cmd, u8 *par,
size_t num)
{
struct spi_device *spi = mipi->spi;
unsigned int bpw = 8;
void *data = par;
u32 speed_hz;
int i, ret;
__be16 *buf;
buf = kmalloc(32 * sizeof(u16), GFP_KERNEL);
if (!buf)
return -ENOMEM;
/*
* The displays are Raspberry Pi HATs and connected to the 8-bit only
* SPI controller, so 16-bit command and parameters need byte swapping
* before being transferred as 8-bit on the big endian SPI bus.
*/
buf[0] = cpu_to_be16(*cmd);
spi_bus_lock(spi->controller);
gpiod_set_value_cansleep(mipi->dc, 0);
speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 2);
ret = mipi_dbi_spi_transfer(spi, speed_hz, 8, buf, 2);
spi_bus_unlock(spi->controller);
if (ret || !num)
goto free;
/* 8-bit configuration data, not 16-bit pixel data */
if (num <= 32) {
for (i = 0; i < num; i++)
buf[i] = cpu_to_be16(par[i]);
num *= 2;
data = buf;
}
/*
* Check whether pixel data bytes needs to be swapped or not
*/
if (*cmd == MIPI_DCS_WRITE_MEMORY_START && !mipi->swap_bytes)
bpw = 16;
spi_bus_lock(spi->controller);
gpiod_set_value_cansleep(mipi->dc, 1);
speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num);
ret = mipi_dbi_spi_transfer(spi, speed_hz, bpw, data, num);
spi_bus_unlock(spi->controller);
free:
kfree(buf);
return ret;
}
static void waveshare_enable(struct drm_simple_display_pipe *pipe,
struct drm_crtc_state *crtc_state,
struct drm_plane_state *plane_state)
{
struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
struct mipi_dbi *dbi = &dbidev->dbi;
u8 addr_mode;
int ret, idx;
if (!drm_dev_enter(pipe->crtc.dev, &idx))
return;
DRM_DEBUG_KMS("\n");
ret = mipi_dbi_poweron_conditional_reset(dbidev);
if (ret < 0)
goto out_exit;
if (ret == 1)
goto out_enable;
mipi_dbi_command(dbi, ILI9486_ITFCTR1);
mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
msleep(250);
mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT, 0x55);
mipi_dbi_command(dbi, ILI9486_PWCTRL1, 0x44);
mipi_dbi_command(dbi, ILI9486_VMCTRL1, 0x00, 0x00, 0x00, 0x00);
mipi_dbi_command(dbi, ILI9486_PGAMCTRL,
0x0F, 0x1F, 0x1C, 0x0C, 0x0F, 0x08, 0x48, 0x98,
0x37, 0x0A, 0x13, 0x04, 0x11, 0x0D, 0x0);
mipi_dbi_command(dbi, ILI9486_NGAMCTRL,
0x0F, 0x32, 0x2E, 0x0B, 0x0D, 0x05, 0x47, 0x75,
0x37, 0x06, 0x10, 0x03, 0x24, 0x20, 0x00);
mipi_dbi_command(dbi, ILI9486_DGAMCTRL,
0x0F, 0x32, 0x2E, 0x0B, 0x0D, 0x05, 0x47, 0x75,
0x37, 0x06, 0x10, 0x03, 0x24, 0x20, 0x00);
mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
msleep(100);
out_enable:
switch (dbidev->rotation) {
case 90:
addr_mode = ILI9486_MADCTL_MY;
break;
case 180:
addr_mode = ILI9486_MADCTL_MV;
break;
case 270:
addr_mode = ILI9486_MADCTL_MX;
break;
default:
addr_mode = ILI9486_MADCTL_MV | ILI9486_MADCTL_MY |
ILI9486_MADCTL_MX;
break;
}
addr_mode |= ILI9486_MADCTL_BGR;
mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
mipi_dbi_enable_flush(dbidev, crtc_state, plane_state);
out_exit:
drm_dev_exit(idx);
}
static const struct drm_simple_display_pipe_funcs waveshare_pipe_funcs = {
DRM_MIPI_DBI_SIMPLE_DISPLAY_PIPE_FUNCS(waveshare_enable),
};
static const struct drm_display_mode waveshare_mode = {
DRM_SIMPLE_MODE(480, 320, 73, 49),
};
DEFINE_DRM_GEM_DMA_FOPS(ili9486_fops);
static const struct drm_driver ili9486_driver = {
.driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
.fops = &ili9486_fops,
DRM_GEM_DMA_DRIVER_OPS_VMAP,
.debugfs_init = mipi_dbi_debugfs_init,
.name = "ili9486",
.desc = "Ilitek ILI9486",
.date = "20200118",
.major = 1,
.minor = 0,
};
static const struct of_device_id ili9486_of_match[] = {
{ .compatible = "waveshare,rpi-lcd-35" },
{ .compatible = "ozzmaker,piscreen" },
{},
};
MODULE_DEVICE_TABLE(of, ili9486_of_match);
static const struct spi_device_id ili9486_id[] = {
{ "ili9486", 0 },
{ "rpi-lcd-35", 0 },
{ "piscreen", 0 },
{ }
};
MODULE_DEVICE_TABLE(spi, ili9486_id);
static int ili9486_probe(struct spi_device *spi)
{
struct device *dev = &spi->dev;
struct mipi_dbi_dev *dbidev;
struct drm_device *drm;
struct mipi_dbi *dbi;
struct gpio_desc *dc;
u32 rotation = 0;
int ret;
dbidev = devm_drm_dev_alloc(dev, &ili9486_driver,
struct mipi_dbi_dev, drm);
if (IS_ERR(dbidev))
return PTR_ERR(dbidev);
dbi = &dbidev->dbi;
drm = &dbidev->drm;
dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
if (IS_ERR(dbi->reset))
return dev_err_probe(dev, PTR_ERR(dbi->reset), "Failed to get GPIO 'reset'\n");
dc = devm_gpiod_get(dev, "dc", GPIOD_OUT_LOW);
if (IS_ERR(dc))
return dev_err_probe(dev, PTR_ERR(dc), "Failed to get GPIO 'dc'\n");
dbidev->backlight = devm_of_find_backlight(dev);
if (IS_ERR(dbidev->backlight))
return PTR_ERR(dbidev->backlight);
device_property_read_u32(dev, "rotation", &rotation);
ret = mipi_dbi_spi_init(spi, dbi, dc);
if (ret)
return ret;
dbi->command = waveshare_command;
dbi->read_commands = NULL;
ret = mipi_dbi_dev_init(dbidev, &waveshare_pipe_funcs,
&waveshare_mode, rotation);
if (ret)
return ret;
drm_mode_config_reset(drm);
ret = drm_dev_register(drm, 0);
if (ret)
return ret;
spi_set_drvdata(spi, drm);
drm_fbdev_dma_setup(drm, 0);
return 0;
}
static void ili9486_remove(struct spi_device *spi)
{
struct drm_device *drm = spi_get_drvdata(spi);
drm_dev_unplug(drm);
drm_atomic_helper_shutdown(drm);
}
static void ili9486_shutdown(struct spi_device *spi)
{
drm_atomic_helper_shutdown(spi_get_drvdata(spi));
}
static struct spi_driver ili9486_spi_driver = {
.driver = {
.name = "ili9486",
.of_match_table = ili9486_of_match,
},
.id_table = ili9486_id,
.probe = ili9486_probe,
.remove = ili9486_remove,
.shutdown = ili9486_shutdown,
};
module_spi_driver(ili9486_spi_driver);
MODULE_DESCRIPTION("Ilitek ILI9486 DRM driver");
MODULE_AUTHOR("Kamlesh Gurudasani <[email protected]>");
MODULE_LICENSE("GPL");
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