Resend because the 1st transmission got HTML'ed by my company's mail server. Based on the existing ST7586 driver. But the ST7539 ... - is monochrome only - has 8 VERTICAL pixels per byte - doesn't support any MIPI DCS commands - has (a few) 16 bit commands - doesn't support setting a clipping rect when writing to the RAM - doesn't support rotation (only mirroring of X and/or Y axis) Questions/TODO: - should drivers for such old displays be mainlined? - shall I use mipi_dbi_ although the display doesn't implement MIPI DCS (and has some 16 bit commands)? - can the conversion to 8 vertical pixels/byte (taken from solomon/ssd130x.c) be avoided / simplified / made more efficient? - how to implement setting of the display contrast (required by my application)? - add device tree binding Signed-off-by: Christian Eggers <ceggers@xxxxxxx> --- MAINTAINERS | 6 + drivers/gpu/drm/tiny/Kconfig | 11 + drivers/gpu/drm/tiny/Makefile | 1 + drivers/gpu/drm/tiny/st7539.c | 424 ++++++++++++++++++++++++++++++++++ 4 files changed, 442 insertions(+) create mode 100644 drivers/gpu/drm/tiny/st7539.c diff --git a/MAINTAINERS b/MAINTAINERS index e7d543cf9f6c..7191206c1ae3 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7116,6 +7116,12 @@ S: Maintained F: Documentation/devicetree/bindings/display/panel/samsung,s6d7aa0.yaml F: drivers/gpu/drm/panel/panel-samsung-s6d7aa0.c +DRM DRIVER FOR SITRONIX ST7539 PANELS +M: Christian Eggers <ceggers@xxxxxxx> +S: Maintained +T: git https://gitlab.freedesktop.org/drm/misc/kernel.git +F: drivers/gpu/drm/tiny/st7539.c + DRM DRIVER FOR SITRONIX ST7586 PANELS M: David Lechner <david@xxxxxxxxxxxxxx> S: Maintained diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig index f6889f649bc1..220d2aee9354 100644 --- a/drivers/gpu/drm/tiny/Kconfig +++ b/drivers/gpu/drm/tiny/Kconfig @@ -186,6 +186,17 @@ config TINYDRM_REPAPER If M is selected the module will be called repaper. +config TINYDRM_ST7539 + tristate "DRM support for Sitronix ST7539 display panels" + depends on DRM && SPI + select DRM_KMS_HELPER + select DRM_GEM_DMA_HELPER + select DRM_MIPI_DBI + help + DRM driver for Sitronix ST7539 panels. + + If M is selected the module will be called st7539. + config TINYDRM_ST7586 tristate "DRM support for Sitronix ST7586 display panels" depends on DRM && SPI diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile index 76dde89a044b..0bd217779995 100644 --- a/drivers/gpu/drm/tiny/Makefile +++ b/drivers/gpu/drm/tiny/Makefile @@ -14,5 +14,6 @@ obj-$(CONFIG_TINYDRM_ILI9341) += ili9341.o obj-$(CONFIG_TINYDRM_ILI9486) += ili9486.o obj-$(CONFIG_TINYDRM_MI0283QT) += mi0283qt.o obj-$(CONFIG_TINYDRM_REPAPER) += repaper.o +obj-$(CONFIG_TINYDRM_ST7539) += st7539.o obj-$(CONFIG_TINYDRM_ST7586) += st7586.o obj-$(CONFIG_TINYDRM_ST7735R) += st7735r.o diff --git a/drivers/gpu/drm/tiny/st7539.c b/drivers/gpu/drm/tiny/st7539.c new file mode 100644 index 000000000000..9a6aeea006ef --- /dev/null +++ b/drivers/gpu/drm/tiny/st7539.c @@ -0,0 +1,424 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * DRM driver for Sitronix ST7539 panels + * + * Copyright 2024 Christian Eggers <ceggers@xxxxxxx> + * + * based on st7586.c + * Copyright 2017 David Lechner <david@xxxxxxxxxxxxxx> + */ + +#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_damage_helper.h> +#include <drm/drm_drv.h> +#include <drm/drm_fb_dma_helper.h> +#include <drm/drm_fbdev_dma.h> +#include <drm/drm_format_helper.h> +#include <drm/drm_framebuffer.h> +#include <drm/drm_gem_atomic_helper.h> +#include <drm/drm_gem_dma_helper.h> +#include <drm/drm_gem_framebuffer_helper.h> +#include <drm/drm_managed.h> +#include <drm/drm_mipi_dbi.h> +#include <drm/drm_rect.h> + +/* controller-specific commands */ +#define ST7539_SET_COLUMN_ADDRESS_LSB(CA) (0x00 | ((CA) & 0x0f)) +#define ST7539_SET_COLUMN_ADDRESS_MSB(CA) (0x10 | (((CA) & 0xff) >> 4)) +#define ST7539_SET_SCROLL_LINE(x) (0x40 | ((x) & 0x3f)) +#define ST7539_SET_CONTRAST 0x81 /* + 1 byte value */ +#define ST7539_SET_FPS__76 0xA0 /* 76 fps */ +#define ST7539_SET_FPS__95 0xA1 /* 95 fps */ +#define ST7539_SET_FPS__132 0xA2 /* 132 fps */ +#define ST7539_SET_FPS__168 0xA3 /* 168 fps */ +#define ST7539_SET_DISP_NORMAL 0xA6 /* non inverse */ +#define ST7539_SET_DISP_INVERSE 0xA7 /* inverse display */ +#define ST7539_SET_DISP_OFF 0xAE /* display off and controller power down */ +#define ST7539_SET_DISP_ON 0xAF /* display on and controller power on */ +#define ST7539_SET_PAGE_ADDRESS(PA) (0xB0 | ((PA) & 0xf)) +#define ST7539_SET_SCAN_NORMAL 0xC0 /* MX=0, MY=0 */ +#define ST7539_SET_SCAN_X_INV 0xC2 /* MX=1, MY=0 */ +#define ST7539_SET_SCAN_Y_INV 0xC4 /* MX=0, MY=1 */ +#define ST7539_SET_SCAN_XY_INV 0xC6 /* MX=1, MY=1 */ +#define ST7539_SOFT_RESET 0xE2 +#define ST7539_NOP 0xE3 +#define ST7539_SET_BIAS__1_6 0xE8 /* 1/6 */ +#define ST7539_SET_BIAS__1_7 0xE9 /* 1/7 */ +#define ST7539_SET_BIAS__1_8 0xEA /* 1/8 */ +#define ST7539_SET_BIAS__1_9 0xEB /* 1/9 */ + +#define ST7539_HOR_RES 192 +#define ST7539_VER_RES 64 + +/* slightly modified version of from mipi_dbi_typec3_command() */ +static int st7539_dbi_command_buf(struct mipi_dbi *dbi, + u8 *cmd, size_t cmd_len, + u8 *par, size_t num) +{ + struct spi_device *spi = dbi->spi; + u32 speed_hz; + int ret = 0; + + spi_bus_lock(spi->controller); + gpiod_set_value_cansleep(dbi->dc, 0); + speed_hz = mipi_dbi_spi_cmd_max_speed(spi, cmd_len); + ret = mipi_dbi_spi_transfer(spi, speed_hz, 8, cmd, cmd_len); + spi_bus_unlock(spi->controller); + if (ret || !num) + return ret; + + spi_bus_lock(spi->controller); + gpiod_set_value_cansleep(dbi->dc, 1); + speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num); + ret = mipi_dbi_spi_transfer(spi, speed_hz, 8, par, num); + spi_bus_unlock(spi->controller); + + return ret; +} + +/** + * st7539_dbi_command16 - Command with 2 bytes + * @dbi: MIPI DBI structure + * @cmd: Array of two command bytes + * + * Returns: + * Zero on success, negative error code on failure. + */ +static int st7539_dbi_command16(struct mipi_dbi *dbi, const u8 *cmd) +{ + u8 *cmdbuf; + int ret; + + /* SPI requires dma-safe buffers */ + cmdbuf = kmemdup(cmd, 2, GFP_KERNEL); + if (!cmdbuf) + return -ENOMEM; + + mutex_lock(&dbi->cmdlock); + ret = st7539_dbi_command_buf(dbi, cmdbuf, 2, NULL, 0); + mutex_unlock(&dbi->cmdlock); + + kfree(cmdbuf); + + return ret; +} + +static int st7539_dbi_typec3_command(struct mipi_dbi *dbi, + u8 *cmd, u8 *par, size_t num) +{ + return st7539_dbi_command_buf(dbi, cmd, 1, par, num); +} + +/* + * The ST7539 controller packs 8 VERTICAL pixels into one byte + * (similar as "page_address_mode" for SH1106 in drm/solomon/ssd130x.c). + */ + +static void st7539_xrgb8888_to_mono(u8 *dst, struct iosys_map *src, + struct drm_framebuffer *fb, + struct drm_rect *clip, + struct drm_format_conv_state *fmtcnv_state) +{ + u8 *buf; + struct iosys_map dst_map; + + unsigned int width = drm_rect_width(clip); + unsigned int height = drm_rect_height(clip); + unsigned int line_length = DIV_ROUND_UP(width, 8); + unsigned int page_height = 8; + unsigned int pages = DIV_ROUND_UP(height, page_height); + size_t len = pages * width; + u32 array_idx = 0; + int i, j, k; + + /* intermediate buffer (8 horizontal pixels per byte) */ + buf = kmalloc(len, GFP_KERNEL); + if (!buf) + return; + + iosys_map_set_vaddr(&dst_map, buf); + drm_fb_xrgb8888_to_mono(&dst_map, NULL, src, fb, clip, fmtcnv_state); + + /* convert to 8 VERTICAL pixels per byte */ + for (i = 0; i < pages; i++) { + for (j = 0; j < width; j++) { + u8 data = 0; + + for (k = 0; k < 8; k++) { + u8 byte = buf[(8 * i + k) * line_length + j / 8]; + u8 bit = !((byte >> (j % 8)) & 1); /* invert pixels */ + + data |= bit << k; + } + dst[array_idx++] = data; + } + } + + kfree(buf); +} + +static int st7539_buf_copy(void *dst, struct iosys_map *src, struct drm_framebuffer *fb, + struct drm_rect *clip, struct drm_format_conv_state *fmtcnv_state) +{ + int ret; + + ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE); + if (ret) + return ret; + + st7539_xrgb8888_to_mono(dst, src, fb, clip, fmtcnv_state); + + drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE); + + return 0; +} + +static void st7539_fb_dirty(struct iosys_map *src, struct drm_framebuffer *fb, + struct drm_rect *rect, struct drm_format_conv_state *fmtcnv_state) +{ + struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(fb->dev); + struct mipi_dbi *dbi = &dbidev->dbi; + int start, end, ret = 0; + + /* hardware doesn't support clipping of the column --> send full lines */ + rect->x1 = 0; + rect->x2 = ST7539_HOR_RES; + /* 8 pixels per byte, so grow clip to nearest multiple of 8 */ + rect->y1 = rounddown(rect->y1, 8); + rect->y2 = roundup(rect->y2, 8); + + DRM_DEBUG_KMS("Flushing [FB:%d] " DRM_RECT_FMT "\n", fb->base.id, DRM_RECT_ARG(rect)); + + ret = st7539_buf_copy(dbidev->tx_buf, src, fb, rect, fmtcnv_state); + if (ret) + goto err_msg; + + /* Pixels are packed 8 per byte */ + start = rect->y1 / 8; + end = rect->y2 / 8; + + mipi_dbi_command(dbi, ST7539_SET_COLUMN_ADDRESS_LSB(rect->x1 & 0xFF)); + mipi_dbi_command(dbi, ST7539_SET_COLUMN_ADDRESS_MSB((rect->x1 >> 8) & 0xFF)); + + ret = mipi_dbi_command_buf(dbi, ST7539_SET_PAGE_ADDRESS(start), + (u8 *)dbidev->tx_buf, + (rect->x2 - rect->x1) * (end - start)); +err_msg: + if (ret) + dev_err_once(fb->dev->dev, "Failed to update display %d\n", ret); +} + +static void st7539_pipe_update(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *old_state) +{ + struct drm_plane_state *state = pipe->plane.state; + struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state); + struct drm_framebuffer *fb = state->fb; + struct drm_rect rect; + int idx; + + if (!pipe->crtc.state->active) + return; + + if (!drm_dev_enter(fb->dev, &idx)) + return; + + if (drm_atomic_helper_damage_merged(old_state, state, &rect)) + st7539_fb_dirty(&shadow_plane_state->data[0], fb, &rect, + &shadow_plane_state->fmtcnv_state); + + drm_dev_exit(idx); +} + +static void st7539_pipe_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 drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state); + struct drm_framebuffer *fb = plane_state->fb; + struct mipi_dbi *dbi = &dbidev->dbi; + struct drm_rect rect = { + .x1 = 0, + .x2 = fb->width, + .y1 = 0, + .y2 = fb->height, + }; + int idx; + + if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return; + + DRM_DEBUG_KMS("\n"); + + /* Cannot use mipi_dbi_poweron_reset() here as the ST7539 has a non DCI + * opcode for soft reset + */ + mipi_dbi_hw_reset(dbi); + + mipi_dbi_command(dbi, ST7539_SOFT_RESET); + mipi_dbi_command(dbi, ST7539_SET_FPS__76); + mipi_dbi_command(dbi, ST7539_SET_BIAS__1_9); + st7539_dbi_command16(dbi, (u8[]){ST7539_SET_CONTRAST, 120}); + mipi_dbi_command(dbi, ST7539_SET_SCAN_Y_INV); /* ToDo: make this configurable */ + + st7539_fb_dirty(&shadow_plane_state->data[0], fb, &rect, + &shadow_plane_state->fmtcnv_state); + + mipi_dbi_command(dbi, ST7539_SET_DISP_ON); +} + +static void st7539_pipe_disable(struct drm_simple_display_pipe *pipe) +{ + struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev); + + /* + * This callback is not protected by drm_dev_enter/exit since we want to + * turn off the display on regular driver unload. It's highly unlikely + * that the underlying SPI controller is gone should this be called after + * unplug. + */ + + DRM_DEBUG_KMS("\n"); + + mipi_dbi_command(&dbidev->dbi, MIPI_DCS_SET_DISPLAY_OFF); +} + +static const u32 st7539_formats[] = { + DRM_FORMAT_XRGB8888, +}; + +static const struct drm_simple_display_pipe_funcs st7539_pipe_funcs = { + .mode_valid = mipi_dbi_pipe_mode_valid, + .enable = st7539_pipe_enable, + .disable = st7539_pipe_disable, + .update = st7539_pipe_update, + .begin_fb_access = mipi_dbi_pipe_begin_fb_access, + .end_fb_access = mipi_dbi_pipe_end_fb_access, + .reset_plane = mipi_dbi_pipe_reset_plane, + .duplicate_plane_state = mipi_dbi_pipe_duplicate_plane_state, + .destroy_plane_state = mipi_dbi_pipe_destroy_plane_state, +}; + +static const struct drm_display_mode st7539_mode = { + DRM_SIMPLE_MODE(ST7539_HOR_RES, ST7539_VER_RES, 57, 23), +}; + +DEFINE_DRM_GEM_DMA_FOPS(st7539_fops); + +static const struct drm_driver st7539_driver = { + .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC, + .fops = &st7539_fops, + DRM_GEM_DMA_DRIVER_OPS_VMAP, + .debugfs_init = mipi_dbi_debugfs_init, + .name = "st7539", + .desc = "Sitronix ST7539", + .date = "20240624", + .major = 1, + .minor = 0, +}; + +static const struct of_device_id st7539_of_match[] = { + { .compatible = "sitronix,st7539" }, + {}, +}; +MODULE_DEVICE_TABLE(of, st7539_of_match); + +static const struct spi_device_id st7539_id[] = { + { "st7539", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(spi, st7539_id); + +static int st7539_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 *a0; + size_t bufsize; + int ret; + + dbidev = devm_drm_dev_alloc(dev, &st7539_driver, + struct mipi_dbi_dev, drm); + if (IS_ERR(dbidev)) + return PTR_ERR(dbidev); + + dbi = &dbidev->dbi; + drm = &dbidev->drm; + + bufsize = DIV_ROUND_UP(st7539_mode.vdisplay, 8) * st7539_mode.hdisplay; + + 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"); + + a0 = devm_gpiod_get(dev, "a0", GPIOD_OUT_LOW); + if (IS_ERR(a0)) + return dev_err_probe(dev, PTR_ERR(a0), "Failed to get GPIO 'a0'\n"); + + ret = mipi_dbi_spi_init(spi, dbi, a0); + if (ret) + return ret; + + /* override the command function set in mipi_dbi_spi_init() */ + dbi->command = st7539_dbi_typec3_command; + + /* Cannot read from this controller via SPI */ + dbi->read_commands = NULL; + + ret = mipi_dbi_dev_init_with_formats(dbidev, &st7539_pipe_funcs, + st7539_formats, ARRAY_SIZE(st7539_formats), + &st7539_mode, 0, bufsize); + 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 st7539_remove(struct spi_device *spi) +{ + struct drm_device *drm = spi_get_drvdata(spi); + + drm_dev_unplug(drm); + drm_atomic_helper_shutdown(drm); +} + +static void st7539_shutdown(struct spi_device *spi) +{ + drm_atomic_helper_shutdown(spi_get_drvdata(spi)); +} + +static struct spi_driver st7539_spi_driver = { + .driver = { + .name = "st7539", + .of_match_table = st7539_of_match, + }, + .id_table = st7539_id, + .probe = st7539_probe, + .remove = st7539_remove, + .shutdown = st7539_shutdown, +}; +module_spi_driver(st7539_spi_driver); + +MODULE_DESCRIPTION("Sitronix ST7539 DRM driver"); +MODULE_AUTHOR("Christian Eggers <ceggers@xxxxxxx>"); +MODULE_LICENSE("GPL"); -- 2.43.0
