diff options
Diffstat (limited to 'drivers/gpu/drm/tinydrm/st7586.c')
| -rw-r--r-- | drivers/gpu/drm/tinydrm/st7586.c | 428 |
1 files changed, 428 insertions, 0 deletions
diff --git a/drivers/gpu/drm/tinydrm/st7586.c b/drivers/gpu/drm/tinydrm/st7586.c new file mode 100644 index 000000000000..1b39d3fb17f7 --- /dev/null +++ b/drivers/gpu/drm/tinydrm/st7586.c @@ -0,0 +1,428 @@ +/* + * DRM driver for Sitronix ST7586 panels + * + * Copyright 2017 David Lechner <david@lechnology.com> + * + * 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. + */ + +#include <linux/delay.h> +#include <linux/dma-buf.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/tinydrm/mipi-dbi.h> +#include <drm/tinydrm/tinydrm-helpers.h> + +/* controller-specific commands */ +#define ST7586_DISP_MODE_GRAY 0x38 +#define ST7586_DISP_MODE_MONO 0x39 +#define ST7586_ENABLE_DDRAM 0x3a +#define ST7586_SET_DISP_DUTY 0xb0 +#define ST7586_SET_PART_DISP 0xb4 +#define ST7586_SET_NLINE_INV 0xb5 +#define ST7586_SET_VOP 0xc0 +#define ST7586_SET_BIAS_SYSTEM 0xc3 +#define ST7586_SET_BOOST_LEVEL 0xc4 +#define ST7586_SET_VOP_OFFSET 0xc7 +#define ST7586_ENABLE_ANALOG 0xd0 +#define ST7586_AUTO_READ_CTRL 0xd7 +#define ST7586_OTP_RW_CTRL 0xe0 +#define ST7586_OTP_CTRL_OUT 0xe1 +#define ST7586_OTP_READ 0xe3 + +#define ST7586_DISP_CTRL_MX BIT(6) +#define ST7586_DISP_CTRL_MY BIT(7) + +/* + * The ST7586 controller has an unusual pixel format where 2bpp grayscale is + * packed 3 pixels per byte with the first two pixels using 3 bits and the 3rd + * pixel using only 2 bits. + * + * | D7 | D6 | D5 || | || 2bpp | + * | (D4) | (D3) | (D2) || D1 | D0 || GRAY | + * +------+------+------++------+------++------+ + * | 1 | 1 | 1 || 1 | 1 || 0 0 | black + * | 1 | 0 | 0 || 1 | 0 || 0 1 | dark gray + * | 0 | 1 | 0 || 0 | 1 || 1 0 | light gray + * | 0 | 0 | 0 || 0 | 0 || 1 1 | white + */ + +static const u8 st7586_lookup[] = { 0x7, 0x4, 0x2, 0x0 }; + +static void st7586_xrgb8888_to_gray332(u8 *dst, void *vaddr, + struct drm_framebuffer *fb, + struct drm_clip_rect *clip) +{ + size_t len = (clip->x2 - clip->x1) * (clip->y2 - clip->y1); + unsigned int x, y; + u8 *src, *buf, val; + + buf = kmalloc(len, GFP_KERNEL); + if (!buf) + return; + + tinydrm_xrgb8888_to_gray8(buf, vaddr, fb, clip); + src = buf; + + for (y = clip->y1; y < clip->y2; y++) { + for (x = clip->x1; x < clip->x2; x += 3) { + val = st7586_lookup[*src++ >> 6] << 5; + val |= st7586_lookup[*src++ >> 6] << 2; + val |= st7586_lookup[*src++ >> 6] >> 1; + *dst++ = val; + } + } + + kfree(buf); +} + +static int st7586_buf_copy(void *dst, struct drm_framebuffer *fb, + struct drm_clip_rect *clip) +{ + struct drm_gem_cma_object *cma_obj = drm_fb_cma_get_gem_obj(fb, 0); + struct dma_buf_attachment *import_attach = cma_obj->base.import_attach; + void *src = cma_obj->vaddr; + int ret = 0; + + if (import_attach) { + ret = dma_buf_begin_cpu_access(import_attach->dmabuf, + DMA_FROM_DEVICE); + if (ret) + return ret; + } + + st7586_xrgb8888_to_gray332(dst, src, fb, clip); + + if (import_attach) + ret = dma_buf_end_cpu_access(import_attach->dmabuf, + DMA_FROM_DEVICE); + + return ret; +} + +static int st7586_fb_dirty(struct drm_framebuffer *fb, + struct drm_file *file_priv, unsigned int flags, + unsigned int color, struct drm_clip_rect *clips, + unsigned int num_clips) +{ + struct tinydrm_device *tdev = fb->dev->dev_private; + struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev); + struct drm_clip_rect clip; + int start, end; + int ret = 0; + + mutex_lock(&tdev->dirty_lock); + + if (!mipi->enabled) + goto out_unlock; + + /* fbdev can flush even when we're not interested */ + if (tdev->pipe.plane.fb != fb) + goto out_unlock; + + tinydrm_merge_clips(&clip, clips, num_clips, flags, fb->width, + fb->height); + + /* 3 pixels per byte, so grow clip to nearest multiple of 3 */ + clip.x1 = rounddown(clip.x1, 3); + clip.x2 = roundup(clip.x2, 3); + + DRM_DEBUG("Flushing [FB:%d] x1=%u, x2=%u, y1=%u, y2=%u\n", fb->base.id, + clip.x1, clip.x2, clip.y1, clip.y2); + + ret = st7586_buf_copy(mipi->tx_buf, fb, &clip); + if (ret) + goto out_unlock; + + /* Pixels are packed 3 per byte */ + start = clip.x1 / 3; + end = clip.x2 / 3; + + mipi_dbi_command(mipi, MIPI_DCS_SET_COLUMN_ADDRESS, + (start >> 8) & 0xFF, start & 0xFF, + (end >> 8) & 0xFF, (end - 1) & 0xFF); + mipi_dbi_command(mipi, MIPI_DCS_SET_PAGE_ADDRESS, + (clip.y1 >> 8) & 0xFF, clip.y1 & 0xFF, + (clip.y2 >> 8) & 0xFF, (clip.y2 - 1) & 0xFF); + + ret = mipi_dbi_command_buf(mipi, MIPI_DCS_WRITE_MEMORY_START, + (u8 *)mipi->tx_buf, + (end - start) * (clip.y2 - clip.y1)); + +out_unlock: + mutex_unlock(&tdev->dirty_lock); + + if (ret) + dev_err_once(fb->dev->dev, "Failed to update display %d\n", + ret); + + return ret; +} + +static const struct drm_framebuffer_funcs st7586_fb_funcs = { + .destroy = drm_fb_cma_destroy, + .create_handle = drm_fb_cma_create_handle, + .dirty = st7586_fb_dirty, +}; + +void st7586_pipe_enable(struct drm_simple_display_pipe *pipe, + struct drm_crtc_state *crtc_state) +{ + struct tinydrm_device *tdev = pipe_to_tinydrm(pipe); + struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev); + struct drm_framebuffer *fb = pipe->plane.fb; + struct device *dev = tdev->drm->dev; + int ret; + u8 addr_mode; + + DRM_DEBUG_KMS("\n"); + + mipi_dbi_hw_reset(mipi); + ret = mipi_dbi_command(mipi, ST7586_AUTO_READ_CTRL, 0x9f); + if (ret) { + dev_err(dev, "Error sending command %d\n", ret); + return; + } + + mipi_dbi_command(mipi, ST7586_OTP_RW_CTRL, 0x00); + + msleep(10); + + mipi_dbi_command(mipi, ST7586_OTP_READ); + + msleep(20); + + mipi_dbi_command(mipi, ST7586_OTP_CTRL_OUT); + mipi_dbi_command(mipi, MIPI_DCS_EXIT_SLEEP_MODE); + mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_OFF); + + msleep(50); + + mipi_dbi_command(mipi, ST7586_SET_VOP_OFFSET, 0x00); + mipi_dbi_command(mipi, ST7586_SET_VOP, 0xe3, 0x00); + mipi_dbi_command(mipi, ST7586_SET_BIAS_SYSTEM, 0x02); + mipi_dbi_command(mipi, ST7586_SET_BOOST_LEVEL, 0x04); + mipi_dbi_command(mipi, ST7586_ENABLE_ANALOG, 0x1d); + mipi_dbi_command(mipi, ST7586_SET_NLINE_INV, 0x00); + mipi_dbi_command(mipi, ST7586_DISP_MODE_GRAY); + mipi_dbi_command(mipi, ST7586_ENABLE_DDRAM, 0x02); + + switch (mipi->rotation) { + default: + addr_mode = 0x00; + break; + case 90: + addr_mode = ST7586_DISP_CTRL_MY; + break; + case 180: + addr_mode = ST7586_DISP_CTRL_MX | ST7586_DISP_CTRL_MY; + break; + case 270: + addr_mode = ST7586_DISP_CTRL_MX; + break; + } + mipi_dbi_command(mipi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode); + + mipi_dbi_command(mipi, ST7586_SET_DISP_DUTY, 0x7f); + mipi_dbi_command(mipi, ST7586_SET_PART_DISP, 0xa0); + mipi_dbi_command(mipi, MIPI_DCS_SET_PARTIAL_AREA, 0x00, 0x00, 0x00, 0x77); + mipi_dbi_command(mipi, MIPI_DCS_EXIT_INVERT_MODE); + + msleep(100); + + mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_ON); + + mipi->enabled = true; + + if (fb) + fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0); +} + +static void st7586_pipe_disable(struct drm_simple_display_pipe *pipe) +{ + struct tinydrm_device *tdev = pipe_to_tinydrm(pipe); + struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev); + + DRM_DEBUG_KMS("\n"); + + if (!mipi->enabled) + return; + + mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_OFF); + mipi->enabled = false; +} + +static const u32 st7586_formats[] = { + DRM_FORMAT_XRGB8888, +}; + +static int st7586_init(struct device *dev, struct mipi_dbi *mipi, + const struct drm_simple_display_pipe_funcs *pipe_funcs, + struct drm_driver *driver, const struct drm_display_mode *mode, + unsigned int rotation) +{ + size_t bufsize = (mode->vdisplay + 2) / 3 * mode->hdisplay; + struct tinydrm_device *tdev = &mipi->tinydrm; + int ret; + + mutex_init(&mipi->cmdlock); + + mipi->tx_buf = devm_kmalloc(dev, bufsize, GFP_KERNEL); + if (!mipi->tx_buf) + return -ENOMEM; + + ret = devm_tinydrm_init(dev, tdev, &st7586_fb_funcs, driver); + if (ret) + return ret; + + ret = tinydrm_display_pipe_init(tdev, pipe_funcs, + DRM_MODE_CONNECTOR_VIRTUAL, + st7586_formats, + ARRAY_SIZE(st7586_formats), + mode, rotation); + if (ret) + return ret; + + tdev->drm->mode_config.preferred_depth = 32; + mipi->rotation = rotation; + + drm_mode_config_reset(tdev->drm); + + DRM_DEBUG_KMS("preferred_depth=%u, rotation = %u\n", + tdev->drm->mode_config.preferred_depth, rotation); + + return 0; +} + +static const struct drm_simple_display_pipe_funcs st7586_pipe_funcs = { + .enable = st7586_pipe_enable, + .disable = st7586_pipe_disable, + .update = tinydrm_display_pipe_update, + .prepare_fb = tinydrm_display_pipe_prepare_fb, +}; + +static const struct drm_display_mode st7586_mode = { + TINYDRM_MODE(178, 128, 37, 27), +}; + +DEFINE_DRM_GEM_CMA_FOPS(st7586_fops); + +static struct drm_driver st7586_driver = { + .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_PRIME | + DRIVER_ATOMIC, + .fops = &st7586_fops, + TINYDRM_GEM_DRIVER_OPS, + .lastclose = tinydrm_lastclose, + .debugfs_init = mipi_dbi_debugfs_init, + .name = "st7586", + .desc = "Sitronix ST7586", + .date = "20170801", + .major = 1, + .minor = 0, +}; + +static const struct of_device_id st7586_of_match[] = { + { .compatible = "lego,ev3-lcd" }, + {}, +}; +MODULE_DEVICE_TABLE(of, st7586_of_match); + +static const struct spi_device_id st7586_id[] = { + { "ev3-lcd", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(spi, st7586_id); + +static int st7586_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct tinydrm_device *tdev; + struct mipi_dbi *mipi; + struct gpio_desc *a0; + u32 rotation = 0; + int ret; + + mipi = devm_kzalloc(dev, sizeof(*mipi), GFP_KERNEL); + if (!mipi) + return -ENOMEM; + + mipi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(mipi->reset)) { + dev_err(dev, "Failed to get gpio 'reset'\n"); + return PTR_ERR(mipi->reset); + } + + a0 = devm_gpiod_get(dev, "a0", GPIOD_OUT_LOW); + if (IS_ERR(a0)) { + dev_err(dev, "Failed to get gpio 'a0'\n"); + return PTR_ERR(a0); + } + + device_property_read_u32(dev, "rotation", &rotation); + + ret = mipi_dbi_spi_init(spi, mipi, a0); + if (ret) + return ret; + + /* Cannot read from this controller via SPI */ + mipi->read_commands = NULL; + + /* + * we are using 8-bit data, so we are not actually swapping anything, + * but setting mipi->swap_bytes makes mipi_dbi_typec3_command() do the + * right thing and not use 16-bit transfers (which results in swapped + * bytes on little-endian systems and causes out of order data to be + * sent to the display). + */ + mipi->swap_bytes = true; + + ret = st7586_init(&spi->dev, mipi, &st7586_pipe_funcs, &st7586_driver, + &st7586_mode, rotation); + if (ret) + return ret; + + tdev = &mipi->tinydrm; + + ret = devm_tinydrm_register(tdev); + if (ret) + return ret; + + spi_set_drvdata(spi, mipi); + + DRM_DEBUG_DRIVER("Initialized %s:%s @%uMHz on minor %d\n", + tdev->drm->driver->name, dev_name(dev), + spi->max_speed_hz / 1000000, + tdev->drm->primary->index); + + return 0; +} + +static void st7586_shutdown(struct spi_device *spi) +{ + struct mipi_dbi *mipi = spi_get_drvdata(spi); + + tinydrm_shutdown(&mipi->tinydrm); +} + +static struct spi_driver st7586_spi_driver = { + .driver = { + .name = "st7586", + .owner = THIS_MODULE, + .of_match_table = st7586_of_match, + }, + .id_table = st7586_id, + .probe = st7586_probe, + .shutdown = st7586_shutdown, +}; +module_spi_driver(st7586_spi_driver); + +MODULE_DESCRIPTION("Sitronix ST7586 DRM driver"); +MODULE_AUTHOR("David Lechner <david@lechnology.com>"); +MODULE_LICENSE("GPL"); |