Messages in this thread |  | | Subject | Re: [PATCH v4 3/5] drm/tinydrm: add support for LEGO MINDSTORMS EV3 LCD | From | Noralf Trønnes <> | Date | Wed, 9 Aug 2017 19:59:24 +0200 |
| |
Den 07.08.2017 19.39, skrev David Lechner: > LEGO MINDSTORMS EV3 has an LCD with a ST7586 controller. This adds a new > module for the ST7586 controller with parameters for the LEGO MINDSTORMS > EV3 LCD display. > > Signed-off-by: David Lechner <david@lechnology.com> > ---
This looks good, even I understand the pixel packing now :-) Now we wait for the DT maintainers to have their say.
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
> v4 changes: > * correct order for MAINTAINERS entry > * Drop code not used by LEGO EV3 (regulator, backlight, suspend/resume) > * Make gpios required > * Use lookup table for pixel packing algorithm > * Don't modify clip when used as function parameter > * Use roundup/rounddown macros > > > MAINTAINERS | 6 + > drivers/gpu/drm/tinydrm/Kconfig | 10 + > drivers/gpu/drm/tinydrm/Makefile | 1 + > drivers/gpu/drm/tinydrm/st7586.c | 428 +++++++++++++++++++++++++++++++++++++++ > 4 files changed, 445 insertions(+) > create mode 100644 drivers/gpu/drm/tinydrm/st7586.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index a1e772e..19ca3e6 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -4380,6 +4380,12 @@ S: Orphan / Obsolete > F: drivers/gpu/drm/sis/ > F: include/uapi/drm/sis_drm.h > > +DRM DRIVER FOR SITRONIX ST7586 PANELS > +M: David Lechner <david@lechnology.com> > +S: Maintained > +F: drivers/gpu/drm/tinydrm/st7586.c > +F: Documentation/devicetree/bindings/display/st7586.txt > + > DRM DRIVER FOR TDFX VIDEO CARDS > S: Orphan / Obsolete > F: drivers/gpu/drm/tdfx/ > diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig > index f17c3ca..2e790e7 100644 > --- a/drivers/gpu/drm/tinydrm/Kconfig > +++ b/drivers/gpu/drm/tinydrm/Kconfig > @@ -32,3 +32,13 @@ config TINYDRM_REPAPER > 2.71" TFT EPD Panel (E2271CS021) > > If M is selected the module will be called repaper. > + > +config TINYDRM_ST7586 > + tristate "DRM support for Sitronix ST7586 display panels" > + depends on DRM_TINYDRM && SPI > + select TINYDRM_MIPI_DBI > + help > + DRM driver for the following Sitronix ST7586 panels: > + * LEGO MINDSTORMS EV3 > + > + If M is selected the module will be called st7586. > diff --git a/drivers/gpu/drm/tinydrm/Makefile b/drivers/gpu/drm/tinydrm/Makefile > index 95bb4d4..0c184bd 100644 > --- a/drivers/gpu/drm/tinydrm/Makefile > +++ b/drivers/gpu/drm/tinydrm/Makefile > @@ -6,3 +6,4 @@ obj-$(CONFIG_TINYDRM_MIPI_DBI) += mipi-dbi.o > # Displays > obj-$(CONFIG_TINYDRM_MI0283QT) += mi0283qt.o > obj-$(CONFIG_TINYDRM_REPAPER) += repaper.o > +obj-$(CONFIG_TINYDRM_ST7586) += st7586.o > diff --git a/drivers/gpu/drm/tinydrm/st7586.c b/drivers/gpu/drm/tinydrm/st7586.c > new file mode 100644 > index 0000000..1b39d3f > --- /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");
|  |