[PATCH 2/2] drm: tiny: Add st7735s driver
From: Stefan x Nilsson
Date: Wed Sep 06 2023 - 12:23:31 EST
Add a driver for Sitronix st7735s display controller, as well as a
Winstar wf0096atyaa3dnn0 0.96" 80x160 TFT panel.
The driver code is very similar to st7735r, but with adaptations for
the pipe_enable function. There is also optional support to specify
a power regulator for the display.
Signed-off-by: Stefan x Nilsson <stefan.x.nilsson@xxxxxxxx>
---
MAINTAINERS | 1 +
drivers/gpu/drm/tiny/Kconfig | 14 +++
drivers/gpu/drm/tiny/Makefile | 1 +
drivers/gpu/drm/tiny/st7735s.c | 264 +++++++++++++++++++++++++++++++++++++++++
4 files changed, 280 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index c00b2b9086f2..f24295d691e5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6733,6 +6733,7 @@ M: Stefan x Nilsson <stefan.x.nilsson@xxxxxxxx>
S: Maintained
T: git git://anongit.freedesktop.org/drm/drm-misc
F: Documentation/devicetree/bindings/display/sitronix,st7735s.yaml
+F: drivers/gpu/drm/tiny/st7735s.c
DRM DRIVER FOR SOLOMON SSD130X OLED DISPLAYS
M: Javier Martinez Canillas <javierm@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig
index f6889f649bc1..2917f5412ddd 100644
--- a/drivers/gpu/drm/tiny/Kconfig
+++ b/drivers/gpu/drm/tiny/Kconfig
@@ -212,3 +212,17 @@ config TINYDRM_ST7735R
* Okaya RH128128T 1.44" 128x128 TFT
If M is selected the module will be called st7735r.
+
+config TINYDRM_ST7735S
+ tristate "DRM support for Sitronix ST7735S display panels"
+ depends on DRM && SPI
+ select DRM_KMS_HELPER
+ select DRM_GEM_DMA_HELPER
+ select DRM_MIPI_DBI
+ select BACKLIGHT_CLASS_DEVICE
+ help
+ DRM driver for Sitronix ST7735S with one of the following
+ LCDs:
+ * Winstar WF0096ATYAA3DNN0 0.96" 80x160 Color TFT
+
+ If M is selected the module will be called st7735s.
diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile
index 76dde89a044b..2e805c5b6f16 100644
--- a/drivers/gpu/drm/tiny/Makefile
+++ b/drivers/gpu/drm/tiny/Makefile
@@ -16,3 +16,4 @@ obj-$(CONFIG_TINYDRM_MI0283QT) += mi0283qt.o
obj-$(CONFIG_TINYDRM_REPAPER) += repaper.o
obj-$(CONFIG_TINYDRM_ST7586) += st7586.o
obj-$(CONFIG_TINYDRM_ST7735R) += st7735r.o
+obj-$(CONFIG_TINYDRM_ST7735S) += st7735s.o
diff --git a/drivers/gpu/drm/tiny/st7735s.c b/drivers/gpu/drm/tiny/st7735s.c
new file mode 100644
index 000000000000..42290f4128db
--- /dev/null
+++ b/drivers/gpu/drm/tiny/st7735s.c
@@ -0,0 +1,264 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * DRM driver for display panels connected to a Sitronix ST7735S
+ * display controller in SPI mode.
+ *
+ * Copyright (C) 2023 Axis Communications AB
+ */
+
+#include <linux/backlight.h>
+#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/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>
+
+#define ST7735S_FRMCTR1 0xb1
+#define ST7735S_FRMCTR2 0xb2
+#define ST7735S_FRMCTR3 0xb3
+#define ST7735S_INVCTR 0xb4
+#define ST7735S_PWCTR1 0xc0
+#define ST7735S_PWCTR2 0xc1
+#define ST7735S_PWCTR3 0xc2
+#define ST7735S_PWCTR4 0xc3
+#define ST7735S_PWCTR5 0xc4
+#define ST7735S_VMCTR1 0xc5
+#define ST7735S_GAMCTRP1 0xe0
+#define ST7735S_GAMCTRN1 0xe1
+
+#define ST7735S_MY BIT(7)
+#define ST7735S_MX BIT(6)
+#define ST7735S_MV BIT(5)
+#define ST7735S_RGB BIT(3)
+
+struct st7735s_cfg {
+ const struct drm_display_mode mode;
+ unsigned int left_offset;
+ unsigned int top_offset;
+ unsigned int write_only:1;
+ unsigned int rgb:1; /* RGB (vs. BGR) */
+};
+
+struct st7735s_priv {
+ struct mipi_dbi_dev dbidev; /* Must be first for .release() */
+ const struct st7735s_cfg *cfg;
+};
+
+static void st7735s_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 st7735s_priv *priv = container_of(dbidev, struct st7735s_priv,
+ dbidev);
+ struct mipi_dbi *dbi = &dbidev->dbi;
+ int ret, idx;
+ u8 addr_mode;
+
+ if (!drm_dev_enter(pipe->crtc.dev, &idx))
+ return;
+
+ DRM_DEBUG_KMS("\n");
+
+ ret = mipi_dbi_poweron_reset(dbidev);
+ if (ret)
+ goto out_exit;
+
+ mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
+ msleep(120);
+ mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_OFF);
+
+ mipi_dbi_command(dbi, ST7735S_FRMCTR1, 0x05, 0x3c, 0x3c);
+ mipi_dbi_command(dbi, ST7735S_FRMCTR2, 0x05, 0x3c, 0x3c);
+ mipi_dbi_command(dbi, ST7735S_FRMCTR3, 0x05, 0x3c, 0x3c, 0x05, 0x3c, 0x3c);
+ mipi_dbi_command(dbi, ST7735S_INVCTR, 0x07);
+ mipi_dbi_command(dbi, ST7735S_PWCTR1, 0xe9, 0x09, 0x04);
+ mipi_dbi_command(dbi, ST7735S_PWCTR2, 0xc5);
+ mipi_dbi_command(dbi, ST7735S_PWCTR3, 0x0d, 0x00);
+ mipi_dbi_command(dbi, ST7735S_PWCTR4, 0x8d, 0x6a);
+ mipi_dbi_command(dbi, ST7735S_PWCTR5, 0x8a, 0xee);
+ mipi_dbi_command(dbi, ST7735S_VMCTR1, 0x15);
+ mipi_dbi_command(dbi, MIPI_DCS_ENTER_INVERT_MODE);
+ /* Enable gate power save mode */
+ mipi_dbi_command(dbi, 0xFC, 0xC0);
+ switch (dbidev->rotation) {
+ default:
+ addr_mode = ST7735S_MX | ST7735S_MY;
+ break;
+ case 90:
+ addr_mode = ST7735S_MX | ST7735S_MV;
+ break;
+ case 180:
+ addr_mode = 0;
+ break;
+ case 270:
+ addr_mode = ST7735S_MY | ST7735S_MV;
+ break;
+ }
+
+ if (priv->cfg->rgb)
+ addr_mode |= ST7735S_RGB;
+
+ mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
+ mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT,
+ MIPI_DCS_PIXEL_FMT_16BIT);
+ mipi_dbi_command(dbi, MIPI_DCS_SET_COLUMN_ADDRESS, 0x00, 0x01, 0x00, 0xa0);
+ mipi_dbi_command(dbi, MIPI_DCS_SET_PAGE_ADDRESS, 0x00, 0x1a, 0x00, 0x69);
+ mipi_dbi_command(dbi, ST7735S_GAMCTRP1, 0x07, 0x0e, 0x08, 0x07, 0x10,
+ 0x07, 0x02, 0x07, 0x09, 0x0f, 0x25, 0x36, 0x00, 0x08,
+ 0x04, 0x10);
+ mipi_dbi_command(dbi, ST7735S_GAMCTRN1, 0x0a, 0x0d, 0x08, 0x07, 0x0f,
+ 0x07, 0x02, 0x07, 0x09, 0x0f, 0x25, 0x35, 0x00, 0x09,
+ 0x04, 0x10);
+ mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
+
+ mipi_dbi_enable_flush(dbidev, crtc_state, plane_state);
+out_exit:
+ drm_dev_exit(idx);
+}
+
+static const struct drm_simple_display_pipe_funcs st7735s_pipe_funcs = {
+ DRM_MIPI_DBI_SIMPLE_DISPLAY_PIPE_FUNCS(st7735s_pipe_enable),
+};
+
+static const struct st7735s_cfg wf0096atyaa3dnn0_cfg = {
+ .mode = { DRM_SIMPLE_MODE(80, 160, 11, 22) },
+ .left_offset = 1,
+ .top_offset = 26,
+ .write_only = true,
+ .rgb = true,
+};
+
+DEFINE_DRM_GEM_DMA_FOPS(st7735s_fops);
+
+static const struct drm_driver st7735s_driver = {
+ .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
+ .fops = &st7735s_fops,
+ DRM_GEM_DMA_DRIVER_OPS_VMAP,
+ .debugfs_init = mipi_dbi_debugfs_init,
+ .name = "st7735s",
+ .desc = "Sitronix ST7735S",
+ .date = "20230825",
+ .major = 1,
+ .minor = 0,
+};
+
+static const struct of_device_id st7735s_of_match[] = {
+ { .compatible = "winstar,wf0096atyaa3dnn0", .data = &wf0096atyaa3dnn0_cfg },
+ { },
+};
+MODULE_DEVICE_TABLE(of, st7735s_of_match);
+
+static const struct spi_device_id st7735s_id[] = {
+ { "wf0096atyaa3dnn0", (uintptr_t)&wf0096atyaa3dnn0_cfg },
+ { },
+};
+MODULE_DEVICE_TABLE(spi, st7735s_id);
+
+static int st7735s_probe(struct spi_device *spi)
+{
+ struct device *dev = &spi->dev;
+ const struct st7735s_cfg *cfg;
+ struct mipi_dbi_dev *dbidev;
+ struct st7735s_priv *priv;
+ struct drm_device *drm;
+ struct mipi_dbi *dbi;
+ struct gpio_desc *dc;
+ u32 rotation = 0;
+ int ret;
+
+ cfg = device_get_match_data(&spi->dev);
+ if (!cfg)
+ cfg = (void *)spi_get_device_id(spi)->driver_data;
+
+ priv = devm_drm_dev_alloc(dev, &st7735s_driver,
+ struct st7735s_priv, dbidev.drm);
+ if (IS_ERR(priv))
+ return PTR_ERR(priv);
+
+ dbidev = &priv->dbidev;
+ priv->cfg = cfg;
+
+ 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);
+
+ dbidev->regulator = devm_regulator_get(dev, "power");
+ device_property_read_u32(dev, "rotation", &rotation);
+
+ ret = mipi_dbi_spi_init(spi, dbi, dc);
+ if (ret)
+ return ret;
+
+ if (cfg->write_only)
+ dbi->read_commands = NULL;
+
+ dbidev->left_offset = cfg->left_offset;
+ dbidev->top_offset = cfg->top_offset;
+
+ ret = mipi_dbi_dev_init(dbidev, &st7735s_pipe_funcs, &cfg->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 st7735s_remove(struct spi_device *spi)
+{
+ struct drm_device *drm = spi_get_drvdata(spi);
+
+ drm_dev_unplug(drm);
+ drm_atomic_helper_shutdown(drm);
+}
+
+static void st7735s_shutdown(struct spi_device *spi)
+{
+ drm_atomic_helper_shutdown(spi_get_drvdata(spi));
+}
+
+static struct spi_driver st7735s_spi_driver = {
+ .driver = {
+ .name = "st7735s",
+ .of_match_table = st7735s_of_match,
+ },
+ .id_table = st7735s_id,
+ .probe = st7735s_probe,
+ .remove = st7735s_remove,
+ .shutdown = st7735s_shutdown,
+};
+module_spi_driver(st7735s_spi_driver);
+
+MODULE_DESCRIPTION("Sitronix ST7735S DRM driver");
+MODULE_LICENSE("GPL");
--
2.30.2