diff options
Diffstat (limited to 'drivers/gpu/drm/tiny/ili9486.c')
| -rw-r--r-- | drivers/gpu/drm/tiny/ili9486.c | 282 |
1 files changed, 282 insertions, 0 deletions
diff --git a/drivers/gpu/drm/tiny/ili9486.c b/drivers/gpu/drm/tiny/ili9486.c new file mode 100644 index 000000000..938bceed5 --- /dev/null +++ b/drivers/gpu/drm/tiny/ili9486.c @@ -0,0 +1,282 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * DRM driver for Ilitek ILI9486 panels + * + * Copyright 2020 Kamlesh Gurudasani <kamlesh.gurudasani@gmail.com> + */ + +#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_generic.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_generic_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 <kamlesh.gurudasani@gmail.com>"); +MODULE_LICENSE("GPL"); |