Add support for MIPI DBI interfaced controllers.
Signed-off-by: Noralf Trønnes <noralf at tronnes.org>
---
drivers/gpu/drm/tinydrm/Kconfig | 3 +
drivers/gpu/drm/tinydrm/Makefile | 3 +
drivers/gpu/drm/tinydrm/mipi-dbi.c | 253 +++++++++++++++++++++++++++++++++++++
include/drm/tinydrm/mipi-dbi.h | 24 ++++
4 files changed, 283 insertions(+)
create mode 100644 drivers/gpu/drm/tinydrm/mipi-dbi.c
create mode 100644 include/drm/tinydrm/mipi-dbi.h
diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig
index 739be06..8c41eee 100644
--- a/drivers/gpu/drm/tinydrm/Kconfig
+++ b/drivers/gpu/drm/tinydrm/Kconfig
@@ -10,4 +10,7 @@ menuconfig DRM_TINYDRM
Choose this option if you have a tinydrm supported display.
If M is selected the module will be called tinydrm.
+config TINYDRM_MIPI_DBI
+ tristate
+
source "drivers/gpu/drm/tinydrm/lcdreg/Kconfig"
diff --git a/drivers/gpu/drm/tinydrm/Makefile b/drivers/gpu/drm/tinydrm/Makefile
index f4a92d9..35ba822 100644
--- a/drivers/gpu/drm/tinydrm/Makefile
+++ b/drivers/gpu/drm/tinydrm/Makefile
@@ -1,2 +1,5 @@
obj-$(CONFIG_DRM_TINYDRM) += core/
obj-$(CONFIG_LCDREG) += lcdreg/
+
+# Controllers
+obj-$(CONFIG_TINYDRM_MIPI_DBI) += mipi-dbi.o
diff --git a/drivers/gpu/drm/tinydrm/mipi-dbi.c
b/drivers/gpu/drm/tinydrm/mipi-dbi.c
new file mode 100644
index 0000000..1ddccb7
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/mipi-dbi.c
@@ -0,0 +1,253 @@
+/*
+ * MIPI Display Bus Interface (DBI) LCD controller support
+ *
+ * Copyright 2016 Noralf Trønnes
+ *
+ * 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 <drm/drm_gem_cma_helper.h>
+#include <drm/tinydrm/lcdreg.h>
+#include <drm/tinydrm/tinydrm.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/swab.h>
+#include <video/mipi_display.h>
+
+#define DCS_POWER_MODE_DISPLAY BIT(2)
+#define DCS_POWER_MODE_DISPLAY_NORMAL_MODE BIT(3)
+#define DCS_POWER_MODE_SLEEP_MODE BIT(4)
+#define DCS_POWER_MODE_PARTIAL_MODE BIT(5)
+#define DCS_POWER_MODE_IDLE_MODE BIT(6)
+#define DCS_POWER_MODE_RESERVED_MASK (BIT(0) | BIT(1) | BIT(7))
+
+/* TODO: Move common functions to a separate module */
+void tinydrm_xrgb8888_to_rgb565(u32 *src, u16 *dst, unsigned num_pixels,
+ bool swap_bytes)
+{
+ int i;
+
+ for (i = 0; i < num_pixels; i++) {
+ *dst = ((*src & 0x00F80000) >> 8) |
+ ((*src & 0x0000FC00) >> 5) |
+ ((*src & 0x000000F8) >> 3);
+ if (swap_bytes)
+ *dst = swab16(*dst);
+ src++;
+ dst++;
+ }
+}
+
+int tinydrm_update_rgb565_lcdreg(struct lcdreg *reg, u32 regnr,
+ struct drm_framebuffer *fb, void *vmem,
+ struct drm_clip_rect *clip)
+{
+ unsigned width = clip->x2 - clip->x1 + 1;
+ unsigned height = clip->y2 - clip->y1 + 1;
+ unsigned num_pixels = width * height;
+ struct lcdreg_transfer tr = {
+ .index = 1,
+ .width = 16,
+ .count = num_pixels
+ };
+ bool byte_swap = false;
+ u16 *buf = NULL;
+ int ret;
+
+ dev_dbg(reg->dev, "%s: x1=%u, x2=%u, y1=%u, y2=%u : width=%u,
height=%u\n",
+ __func__, clip->x1, clip->x2, clip->y1, clip->y2, width,
height);
+ dev_dbg_once(reg->dev, "pixel_format = %s, bpw = 0x%08x\n",
+ drm_get_format_name(fb->pixel_format),
+ reg->bits_per_word_mask);
+
+ if (width != fb->width) {
+ dev_err(reg->dev,
+ "Only full width clips are supported: x1=%u, x2=%u\n",
+ clip->x1, clip->x2);
+ return -EINVAL;
+ }
+
+ switch (fb->pixel_format) {
+ case DRM_FORMAT_RGB565:
+ vmem += clip->y1 * width * 2;
+ tr.buf = vmem;
+ break;
+ case DRM_FORMAT_XRGB8888:
+ vmem += clip->y1 * width * 4;
+ buf = kmalloc(num_pixels * sizeof(u16), GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+#if defined(__LITTLE_ENDIAN)
+ byte_swap = !lcdreg_bpw_supported(reg, 16);
+#endif
+ tinydrm_xrgb8888_to_rgb565(vmem, buf, num_pixels, byte_swap);
+ tr.buf = buf;
+ if (byte_swap) {
+ tr.width = 8;
+ tr.count *= 2;
+ }
+ break;
+ default:
+ dev_err_once(reg->dev, "pixel_format '%s' is not supported\n",
+ drm_get_format_name(fb->pixel_format));
+ return -EINVAL;
+ }
+
+ ret = lcdreg_write(reg, regnr, &tr);
+ kfree(buf);
+
+ return ret;
+}
+
+/* TODO remove when the drm_clip_rect functions have a home */
+void drm_clip_rect_sanetize(struct drm_clip_rect *clip, u32 width, u32 height);
+void drm_clip_rect_merge(struct drm_clip_rect *dst,
+ struct drm_clip_rect *src, unsigned num_clips,
+ unsigned flags, u32 width, u32 height);
+
+static int mipi_dbi_dirtyfb(struct drm_framebuffer *fb, void *vmem,
+ unsigned flags, unsigned color,
+ struct drm_clip_rect *clips, unsigned num_clips)
+{
+ struct tinydrm_device *tdev = fb->dev->dev_private;
+ struct lcdreg *reg = tdev->lcdreg;
+ struct drm_clip_rect clip = { 0 };
+ int ret;
+
+ drm_clip_rect_merge(&clip, clips, num_clips, flags,
+ fb->width, fb->height);
+ drm_clip_rect_sanetize(&clip, fb->width, fb->height);
+
+ dev_dbg(tdev->base->dev, "%s: vmem=%p, x1=%u, x2=%u, y1=%u, y2=%u\n",
+ __func__, vmem, clip.x1, clip.x2, clip.y1, clip.y2);
+
+ /* Only full width is supported */
+ clip.x1 = 0;
+ clip.x2 = fb->width - 1;
+
+ lcdreg_writereg(reg, MIPI_DCS_SET_COLUMN_ADDRESS,
+ (clip.x1 >> 8) & 0xFF, clip.x1 & 0xFF,
+ (clip.x2 >> 8) & 0xFF, clip.x2 & 0xFF);
+ lcdreg_writereg(reg, MIPI_DCS_SET_PAGE_ADDRESS,
+ (clip.y1 >> 8) & 0xFF, clip.y1 & 0xFF,
+ (clip.y2 >> 8) & 0xFF, clip.y2 & 0xFF);
+
+ ret = tinydrm_update_rgb565_lcdreg(reg, MIPI_DCS_WRITE_MEMORY_START,
+ fb, vmem, &clip);
+ if (ret)
+ dev_err_once(tdev->base->dev, "Failed to update display %d\n",
+ ret);
+
+ if (tdev->prepared && !tdev->enabled)
+ tinydrm_enable(tdev);
+
+ return ret;
+}
+
+int mipi_dbi_init(struct device *dev, struct tinydrm_device *tdev)
+{
+ tdev->lcdreg->def_width = 8;
+ tdev->dirtyfb = mipi_dbi_dirtyfb;
+
+ return 0;
+}
+EXPORT_SYMBOL(mipi_dbi_init);
+
+/* Returns true if the display can be verified to be on */
+bool mipi_dbi_display_is_on(struct lcdreg *reg)
+{
+ u32 val;
+
+ if (!lcdreg_is_readable(reg))
+ return false;
+
+ if (lcdreg_readreg_buf32(reg, MIPI_DCS_GET_POWER_MODE, &val, 1))
+ return false;
+
+ val &= ~DCS_POWER_MODE_RESERVED_MASK;
+
+ if (val != (DCS_POWER_MODE_DISPLAY |
+ DCS_POWER_MODE_DISPLAY_NORMAL_MODE | DCS_POWER_MODE_SLEEP_MODE))
+ return false;
+
+ DRM_DEBUG_DRIVER("Display is ON\n");
+
+ return true;
+}
+EXPORT_SYMBOL(mipi_dbi_display_is_on);
+
+void mipi_dbi_debug_dump_regs(struct lcdreg *reg)
+{
+ u32 val[4];
+ int ret;
+
+ if (!(lcdreg_is_readable(reg) && (drm_debug & DRM_UT_DRIVER)))
+ return;
+
+ ret = lcdreg_readreg_buf32(reg, MIPI_DCS_GET_DISPLAY_ID, val, 3);
+ if (ret) {
+ dev_warn(reg->dev,
+ "failed to read from controller: %d", ret);
+ return;
+ }
+
+ DRM_DEBUG_DRIVER("Display ID (%02x): %02x %02x %02x\n",
+ MIPI_DCS_GET_DISPLAY_ID, val[0], val[1], val[2]);
+
+ lcdreg_readreg_buf32(reg, MIPI_DCS_GET_DISPLAY_STATUS, val, 4);
+ DRM_DEBUG_DRIVER("Display status (%02x): %02x %02x %02x %02x\n",
+ MIPI_DCS_GET_DISPLAY_STATUS, val[0], val[1], val[2],
val[3]);
+
+ lcdreg_readreg_buf32(reg, MIPI_DCS_GET_POWER_MODE, val, 1);
+ DRM_DEBUG_DRIVER("Power mode (%02x): %02x\n",
+ MIPI_DCS_GET_POWER_MODE, val[0]);
+
+ lcdreg_readreg_buf32(reg, MIPI_DCS_GET_ADDRESS_MODE, val, 1);
+ DRM_DEBUG_DRIVER("Address mode (%02x): %02x\n",
+ MIPI_DCS_GET_ADDRESS_MODE, val[0]);
+
+ lcdreg_readreg_buf32(reg, MIPI_DCS_GET_PIXEL_FORMAT, val, 1);
+ DRM_DEBUG_DRIVER("Pixel format (%02x): %02x\n",
+ MIPI_DCS_GET_PIXEL_FORMAT, val[0]);
+
+ lcdreg_readreg_buf32(reg, MIPI_DCS_GET_DISPLAY_MODE, val, 1);
+ DRM_DEBUG_DRIVER("Display mode (%02x): %02x\n",
+ MIPI_DCS_GET_DISPLAY_MODE, val[0]);
+
+ lcdreg_readreg_buf32(reg, MIPI_DCS_GET_SIGNAL_MODE, val, 1);
+ DRM_DEBUG_DRIVER("Display signal mode (%02x): %02x\n",
+ MIPI_DCS_GET_SIGNAL_MODE, val[0]);
+
+ lcdreg_readreg_buf32(reg, MIPI_DCS_GET_DIAGNOSTIC_RESULT, val, 1);
+ DRM_DEBUG_DRIVER("Diagnostic result (%02x): %02x\n",
+ MIPI_DCS_GET_DIAGNOSTIC_RESULT, val[0]);
+}
+EXPORT_SYMBOL(mipi_dbi_debug_dump_regs);
+
+int mipi_dbi_panel_unprepare(struct drm_panel *panel)
+{
+ struct tinydrm_device *tdev = tinydrm_from_panel(panel);
+ struct lcdreg *reg = tdev->lcdreg;
+
+ /*
+ * Only do this if we have turned off backlight because if it's on the
+ * display will in most cases turn all white when the pixels are
+ * turned off.
+ */
+ if (tdev->backlight) {
+ lcdreg_writereg(reg, MIPI_DCS_SET_DISPLAY_OFF);
+ lcdreg_writereg(reg, MIPI_DCS_ENTER_SLEEP_MODE);
+ }
+
+ if (tdev->regulator)
+ regulator_disable(tdev->regulator);
+
+ return 0;
+}
+EXPORT_SYMBOL(mipi_dbi_panel_unprepare);
+
+MODULE_LICENSE("GPL");
diff --git a/include/drm/tinydrm/mipi-dbi.h b/include/drm/tinydrm/mipi-dbi.h
new file mode 100644
index 0000000..108a73b
--- /dev/null
+++ b/include/drm/tinydrm/mipi-dbi.h
@@ -0,0 +1,24 @@
+/*
+ * MIPI Display Bus Interface (DBI) LCD controller support
+ *
+ * Copyright 2016 Noralf Trønnes
+ *
+ * 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.
+ */
+
+#ifndef __LINUX_MIPI_DBI_H
+#define __LINUX_MIPI_DBI_H
+
+struct tinydrm_device;
+struct drm_panel;
+struct lcdreg;
+
+int mipi_dbi_init(struct device *dev, struct tinydrm_device *tdev);
+bool mipi_dbi_display_is_on(struct lcdreg *reg);
+void mipi_dbi_debug_dump_regs(struct lcdreg *reg);
+int mipi_dbi_panel_unprepare(struct drm_panel *panel);
+
+#endif /* __LINUX_MIPI_DBI_H */
--
2.2.2
