Merge tag 'drm-for-v4.14' of git://people.freedesktop.org/~airlied/linux

Pull drm updates from Dave Airlie:
 "This is the main drm pull request for 4.14 merge window.

  I'm sending this early, as my continuing journey into fatherhood is
  occurring really soon now, I'm going to be mostly useless for the next
  couple of weeks, though I may be able to read email, I doubt I'll be
  doing much patch applications or git sending. If anything urgent pops
  up I've asked Daniel/Jani/Alex/Sean to try and direct stuff towards
  you.

  Outside drm changes:

  Some rcar-du updates that touch the V4L tree, all acks should be in
  place. It adds one export to the radix tree code for new i915 use
  case. There are some minor AGP cleanups (don't see that too often).
  Changes to the vbox driver in staging to avoid breaking compilation.

  Summary:

  core:
   - Atomic helper fixes
   - Atomic UAPI fixes
   - Add YCBCR 4:2:0 support
   - Drop set_busid hook
   - Refactor fb_helper locking
   - Remove a bunch of internal APIs
   - Add a bunch of better default handlers
   - Format modifier/blob plane property added
   - More internal header refactoring
   - Make more internal API names consistent
   - Enhanced syncobj APIs (wait/signal/reset/create signalled)

  bridge:
   - Add Synopsys Designware MIPI DSI host bridge driver

  tiny:
   - Add Pervasive Displays RePaper displays
   - Add support for LEGO MINDSTORMS EV3 LCD

  i915:
   - Lots of GEN10/CNL  support patches
   - drm syncobj support
   - Skylake+ watermark refactoring
   - GVT vGPU 48-bit ppgtt support
   - GVT performance improvements
   - NOA change ioctl
   - CCS (color compression) scanout support
   - GPU reset improvements

  amdgpu:
   - Initial hugepage support
   - BO migration logic rework
   - Vega10 improvements
   - Powerplay fixes
   - Stop reprogramming the MC
   - Fixes for ACP audio on stoney
   - SR-IOV fixes/improvements
   - Command submission overhead improvements

  amdkfd:
   - Non-dGPU upstreaming patches
   - Scratch VA ioctl
   - Image tiling modes
   - Update PM4 headers for new firmware
   - Drop all BUG_ONs.

  nouveau:
   - GP108 modesetting support.
   - Disable MSI on big endian.

  vmwgfx:
   - Add fence fd support.

  msm:
   - Runtime PM improvements

  exynos:
   - NV12MT support
   - Refactor KMS drivers

  imx-drm:
   - Lock scanout channel to improve memory bw
   - Cleanups

  etnaviv:
   - GEM object population fixes

  tegra:
   - Prep work for Tegra186 support
   - PRIME mmap support

  sunxi:
   - HDMI support improvements
   - HDMI CEC support

  omapdrm:
   - HDMI hotplug IRQ support
   - Big driver cleanup
   - OMAP5 DSI support

  rcar-du:
   - vblank fixes
   - VSP1 updates

  arcgpu:
   - Minor fixes

  stm:
   - Add STM32 DSI controller driver

  dw_hdmi:
   - Add support for Rockchip RK3399
   - HDMI CEC support

  atmel-hlcdc:
   - Add 8-bit color support

  vc4:
   - Atomic fixes
   - New ioctl to attach a label to a buffer object
   - HDMI CEC support
   - Allow userspace to dictate rendering order on submit ioctl"

* tag 'drm-for-v4.14' of git://people.freedesktop.org/~airlied/linux: (1074 commits)
  drm/syncobj: Add a signal ioctl (v3)
  drm/syncobj: Add a reset ioctl (v3)
  drm/syncobj: Add a syncobj_array_find helper
  drm/syncobj: Allow wait for submit and signal behavior (v5)
  drm/syncobj: Add a CREATE_SIGNALED flag
  drm/syncobj: Add a callback mechanism for replace_fence (v3)
  drm/syncobj: add sync obj wait interface. (v8)
  i915: Use drm_syncobj_fence_get
  drm/syncobj: Add a race-free drm_syncobj_fence_get helper (v2)
  drm/syncobj: Rename fence_get to find_fence
  drm: kirin: Add mode_valid logic to avoid mode clocks we can't generate
  drm/vmwgfx: Bump the version for fence FD support
  drm/vmwgfx: Add export fence to file descriptor support
  drm/vmwgfx: Add support for imported Fence File Descriptor
  drm/vmwgfx: Prepare to support fence fd
  drm/vmwgfx: Fix incorrect command header offset at restart
  drm/vmwgfx: Support the NOP_ERROR command
  drm/vmwgfx: Restart command buffers after errors
  drm/vmwgfx: Move irq bottom half processing to threads
  drm/vmwgfx: Don't use drm_irq_[un]install
  ...

1 files changed, 1117 insertions, 0 deletions

diff --git a/drivers/gpu/drm/tinydrm/repaper.c b/drivers/gpu/drm/tinydrm/repaper.c
new file mode 100644
index 000000000000..30dc97b3ff21
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/repaper.c
@@ -0,0 +1,1117 @@
+/*
+ * DRM driver for Pervasive Displays RePaper branded e-ink panels
+ *
+ * Copyright 2013-2017 Pervasive Displays, Inc.
+ * Copyright 2017 Noralf Trønnes
+ *
+ * The driver supports:
+ * Material Film: Aurora Mb (V231)
+ * Driver IC: G2 (eTC)
+ *
+ * The controller code was taken from the userspace driver:
+ * https://github.com/repaper/gratis
+ *
+ * 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/of_device.h>
+#include <linux/sched/clock.h>
+#include <linux/spi/spi.h>
+#include <linux/thermal.h>
+
+#include <drm/tinydrm/tinydrm.h>
+#include <drm/tinydrm/tinydrm-helpers.h>
+
+#define REPAPER_RID_G2_COG_ID	0x12
+
+enum repaper_model {
+	E1144CS021 = 1,
+	E1190CS021,
+	E2200CS021,
+	E2271CS021,
+};
+
+enum repaper_stage {         /* Image pixel -> Display pixel */
+	REPAPER_COMPENSATE,  /* B -> W, W -> B (Current Image) */
+	REPAPER_WHITE,       /* B -> N, W -> W (Current Image) */
+	REPAPER_INVERSE,     /* B -> N, W -> B (New Image) */
+	REPAPER_NORMAL       /* B -> B, W -> W (New Image) */
+};
+
+enum repaper_epd_border_byte {
+	REPAPER_BORDER_BYTE_NONE,
+	REPAPER_BORDER_BYTE_ZERO,
+	REPAPER_BORDER_BYTE_SET,
+};
+
+struct repaper_epd {
+	struct tinydrm_device tinydrm;
+	struct spi_device *spi;
+
+	struct gpio_desc *panel_on;
+	struct gpio_desc *border;
+	struct gpio_desc *discharge;
+	struct gpio_desc *reset;
+	struct gpio_desc *busy;
+
+	struct thermal_zone_device *thermal;
+
+	unsigned int height;
+	unsigned int width;
+	unsigned int bytes_per_scan;
+	const u8 *channel_select;
+	unsigned int stage_time;
+	unsigned int factored_stage_time;
+	bool middle_scan;
+	bool pre_border_byte;
+	enum repaper_epd_border_byte border_byte;
+
+	u8 *line_buffer;
+	void *current_frame;
+
+	bool enabled;
+	bool cleared;
+	bool partial;
+};
+
+static inline struct repaper_epd *
+epd_from_tinydrm(struct tinydrm_device *tdev)
+{
+	return container_of(tdev, struct repaper_epd, tinydrm);
+}
+
+static int repaper_spi_transfer(struct spi_device *spi, u8 header,
+				const void *tx, void *rx, size_t len)
+{
+	void *txbuf = NULL, *rxbuf = NULL;
+	struct spi_transfer tr[2] = {};
+	u8 *headerbuf;
+	int ret;
+
+	headerbuf = kmalloc(1, GFP_KERNEL);
+	if (!headerbuf)
+		return -ENOMEM;
+
+	headerbuf[0] = header;
+	tr[0].tx_buf = headerbuf;
+	tr[0].len = 1;
+
+	/* Stack allocated tx? */
+	if (tx && len <= 32) {
+		txbuf = kmalloc(len, GFP_KERNEL);
+		if (!txbuf) {
+			ret = -ENOMEM;
+			goto out_free;
+		}
+		memcpy(txbuf, tx, len);
+	}
+
+	if (rx) {
+		rxbuf = kmalloc(len, GFP_KERNEL);
+		if (!rxbuf) {
+			ret = -ENOMEM;
+			goto out_free;
+		}
+	}
+
+	tr[1].tx_buf = txbuf ? txbuf : tx;
+	tr[1].rx_buf = rxbuf;
+	tr[1].len = len;
+
+	ndelay(80);
+	ret = spi_sync_transfer(spi, tr, 2);
+	if (rx && !ret)
+		memcpy(rx, rxbuf, len);
+
+out_free:
+	kfree(headerbuf);
+	kfree(txbuf);
+	kfree(rxbuf);
+
+	return ret;
+}
+
+static int repaper_write_buf(struct spi_device *spi, u8 reg,
+			     const u8 *buf, size_t len)
+{
+	int ret;
+
+	ret = repaper_spi_transfer(spi, 0x70, &reg, NULL, 1);
+	if (ret)
+		return ret;
+
+	return repaper_spi_transfer(spi, 0x72, buf, NULL, len);
+}
+
+static int repaper_write_val(struct spi_device *spi, u8 reg, u8 val)
+{
+	return repaper_write_buf(spi, reg, &val, 1);
+}
+
+static int repaper_read_val(struct spi_device *spi, u8 reg)
+{
+	int ret;
+	u8 val;
+
+	ret = repaper_spi_transfer(spi, 0x70, &reg, NULL, 1);
+	if (ret)
+		return ret;
+
+	ret = repaper_spi_transfer(spi, 0x73, NULL, &val, 1);
+
+	return ret ? ret : val;
+}
+
+static int repaper_read_id(struct spi_device *spi)
+{
+	int ret;
+	u8 id;
+
+	ret = repaper_spi_transfer(spi, 0x71, NULL, &id, 1);
+
+	return ret ? ret : id;
+}
+
+static void repaper_spi_mosi_low(struct spi_device *spi)
+{
+	const u8 buf[1] = { 0 };
+
+	spi_write(spi, buf, 1);
+}
+
+/* pixels on display are numbered from 1 so even is actually bits 1,3,5,... */
+static void repaper_even_pixels(struct repaper_epd *epd, u8 **pp,
+				const u8 *data, u8 fixed_value, const u8 *mask,
+				enum repaper_stage stage)
+{
+	unsigned int b;
+
+	for (b = 0; b < (epd->width / 8); b++) {
+		if (data) {
+			u8 pixels = data[b] & 0xaa;
+			u8 pixel_mask = 0xff;
+			u8 p1, p2, p3, p4;
+
+			if (mask) {
+				pixel_mask = (mask[b] ^ pixels) & 0xaa;
+				pixel_mask |= pixel_mask >> 1;
+			}
+
+			switch (stage) {
+			case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */
+				pixels = 0xaa | ((pixels ^ 0xaa) >> 1);
+				break;
+			case REPAPER_WHITE:      /* B -> N, W -> W (Current) */
+				pixels = 0x55 + ((pixels ^ 0xaa) >> 1);
+				break;
+			case REPAPER_INVERSE:    /* B -> N, W -> B (New) */
+				pixels = 0x55 | (pixels ^ 0xaa);
+				break;
+			case REPAPER_NORMAL:     /* B -> B, W -> W (New) */
+				pixels = 0xaa | (pixels >> 1);
+				break;
+			}
+
+			pixels = (pixels & pixel_mask) | (~pixel_mask & 0x55);
+			p1 = (pixels >> 6) & 0x03;
+			p2 = (pixels >> 4) & 0x03;
+			p3 = (pixels >> 2) & 0x03;
+			p4 = (pixels >> 0) & 0x03;
+			pixels = (p1 << 0) | (p2 << 2) | (p3 << 4) | (p4 << 6);
+			*(*pp)++ = pixels;
+		} else {
+			*(*pp)++ = fixed_value;
+		}
+	}
+}
+
+/* pixels on display are numbered from 1 so odd is actually bits 0,2,4,... */
+static void repaper_odd_pixels(struct repaper_epd *epd, u8 **pp,
+			       const u8 *data, u8 fixed_value, const u8 *mask,
+			       enum repaper_stage stage)
+{
+	unsigned int b;
+
+	for (b = epd->width / 8; b > 0; b--) {
+		if (data) {
+			u8 pixels = data[b - 1] & 0x55;
+			u8 pixel_mask = 0xff;
+
+			if (mask) {
+				pixel_mask = (mask[b - 1] ^ pixels) & 0x55;
+				pixel_mask |= pixel_mask << 1;
+			}
+
+			switch (stage) {
+			case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */
+				pixels = 0xaa | (pixels ^ 0x55);
+				break;
+			case REPAPER_WHITE:      /* B -> N, W -> W (Current) */
+				pixels = 0x55 + (pixels ^ 0x55);
+				break;
+			case REPAPER_INVERSE:    /* B -> N, W -> B (New) */
+				pixels = 0x55 | ((pixels ^ 0x55) << 1);
+				break;
+			case REPAPER_NORMAL:     /* B -> B, W -> W (New) */
+				pixels = 0xaa | pixels;
+				break;
+			}
+
+			pixels = (pixels & pixel_mask) | (~pixel_mask & 0x55);
+			*(*pp)++ = pixels;
+		} else {
+			*(*pp)++ = fixed_value;
+		}
+	}
+}
+
+/* interleave bits: (byte)76543210 -> (16 bit).7.6.5.4.3.2.1 */
+static inline u16 repaper_interleave_bits(u16 value)
+{
+	value = (value | (value << 4)) & 0x0f0f;
+	value = (value | (value << 2)) & 0x3333;
+	value = (value | (value << 1)) & 0x5555;
+
+	return value;
+}
+
+/* pixels on display are numbered from 1 */
+static void repaper_all_pixels(struct repaper_epd *epd, u8 **pp,
+			       const u8 *data, u8 fixed_value, const u8 *mask,
+			       enum repaper_stage stage)
+{
+	unsigned int b;
+
+	for (b = epd->width / 8; b > 0; b--) {
+		if (data) {
+			u16 pixels = repaper_interleave_bits(data[b - 1]);
+			u16 pixel_mask = 0xffff;
+
+			if (mask) {
+				pixel_mask = repaper_interleave_bits(mask[b - 1]);
+
+				pixel_mask = (pixel_mask ^ pixels) & 0x5555;
+				pixel_mask |= pixel_mask << 1;
+			}
+
+			switch (stage) {
+			case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */
+				pixels = 0xaaaa | (pixels ^ 0x5555);
+				break;
+			case REPAPER_WHITE:      /* B -> N, W -> W (Current) */
+				pixels = 0x5555 + (pixels ^ 0x5555);
+				break;
+			case REPAPER_INVERSE:    /* B -> N, W -> B (New) */
+				pixels = 0x5555 | ((pixels ^ 0x5555) << 1);
+				break;
+			case REPAPER_NORMAL:     /* B -> B, W -> W (New) */
+				pixels = 0xaaaa | pixels;
+				break;
+			}
+
+			pixels = (pixels & pixel_mask) | (~pixel_mask & 0x5555);
+			*(*pp)++ = pixels >> 8;
+			*(*pp)++ = pixels;
+		} else {
+			*(*pp)++ = fixed_value;
+			*(*pp)++ = fixed_value;
+		}
+	}
+}
+
+/* output one line of scan and data bytes to the display */
+static void repaper_one_line(struct repaper_epd *epd, unsigned int line,
+			     const u8 *data, u8 fixed_value, const u8 *mask,
+			     enum repaper_stage stage)
+{
+	u8 *p = epd->line_buffer;
+	unsigned int b;
+
+	repaper_spi_mosi_low(epd->spi);
+
+	if (epd->pre_border_byte)
+		*p++ = 0x00;
+
+	if (epd->middle_scan) {
+		/* data bytes */
+		repaper_odd_pixels(epd, &p, data, fixed_value, mask, stage);
+
+		/* scan line */
+		for (b = epd->bytes_per_scan; b > 0; b--) {
+			if (line / 4 == b - 1)
+				*p++ = 0x03 << (2 * (line & 0x03));
+			else
+				*p++ = 0x00;
+		}
+
+		/* data bytes */
+		repaper_even_pixels(epd, &p, data, fixed_value, mask, stage);
+	} else {
+		/*
+		 * even scan line, but as lines on display are numbered from 1,
+		 * line: 1,3,5,...
+		 */
+		for (b = 0; b < epd->bytes_per_scan; b++) {
+			if (0 != (line & 0x01) && line / 8 == b)
+				*p++ = 0xc0 >> (line & 0x06);
+			else
+				*p++ = 0x00;
+		}
+
+		/* data bytes */
+		repaper_all_pixels(epd, &p, data, fixed_value, mask, stage);
+
+		/*
+		 * odd scan line, but as lines on display are numbered from 1,
+		 * line: 0,2,4,6,...
+		 */
+		for (b = epd->bytes_per_scan; b > 0; b--) {
+			if (0 == (line & 0x01) && line / 8 == b - 1)
+				*p++ = 0x03 << (line & 0x06);
+			else
+				*p++ = 0x00;
+		}
+	}
+
+	switch (epd->border_byte) {
+	case REPAPER_BORDER_BYTE_NONE:
+		break;
+
+	case REPAPER_BORDER_BYTE_ZERO:
+		*p++ = 0x00;
+		break;
+
+	case REPAPER_BORDER_BYTE_SET:
+		switch (stage) {
+		case REPAPER_COMPENSATE:
+		case REPAPER_WHITE:
+		case REPAPER_INVERSE:
+			*p++ = 0x00;
+			break;
+		case REPAPER_NORMAL:
+			*p++ = 0xaa;
+			break;
+		}
+		break;
+	}
+
+	repaper_write_buf(epd->spi, 0x0a, epd->line_buffer,
+			  p - epd->line_buffer);
+
+	/* Output data to panel */
+	repaper_write_val(epd->spi, 0x02, 0x07);
+
+	repaper_spi_mosi_low(epd->spi);
+}
+
+static void repaper_frame_fixed(struct repaper_epd *epd, u8 fixed_value,
+				enum repaper_stage stage)
+{
+	unsigned int line;
+
+	for (line = 0; line < epd->height; line++)
+		repaper_one_line(epd, line, NULL, fixed_value, NULL, stage);
+}
+
+static void repaper_frame_data(struct repaper_epd *epd, const u8 *image,
+			       const u8 *mask, enum repaper_stage stage)
+{
+	unsigned int line;
+
+	if (!mask) {
+		for (line = 0; line < epd->height; line++) {
+			repaper_one_line(epd, line,
+					 &image[line * (epd->width / 8)],
+					 0, NULL, stage);
+		}
+	} else {
+		for (line = 0; line < epd->height; line++) {
+			size_t n = line * epd->width / 8;
+
+			repaper_one_line(epd, line, &image[n], 0, &mask[n],
+					 stage);
+		}
+	}
+}
+
+static void repaper_frame_fixed_repeat(struct repaper_epd *epd, u8 fixed_value,
+				       enum repaper_stage stage)
+{
+	u64 start = local_clock();
+	u64 end = start + (epd->factored_stage_time * 1000 * 1000);
+
+	do {
+		repaper_frame_fixed(epd, fixed_value, stage);
+	} while (local_clock() < end);
+}
+
+static void repaper_frame_data_repeat(struct repaper_epd *epd, const u8 *image,
+				      const u8 *mask, enum repaper_stage stage)
+{
+	u64 start = local_clock();
+	u64 end = start + (epd->factored_stage_time * 1000 * 1000);
+
+	do {
+		repaper_frame_data(epd, image, mask, stage);
+	} while (local_clock() < end);
+}
+
+static void repaper_get_temperature(struct repaper_epd *epd)
+{
+	int ret, temperature = 0;
+	unsigned int factor10x;
+
+	if (!epd->thermal)
+		return;
+
+	ret = thermal_zone_get_temp(epd->thermal, &temperature);
+	if (ret) {
+		dev_err(&epd->spi->dev, "Failed to get temperature (%d)\n",
+			ret);
+		return;
+	}
+
+	temperature /= 1000;
+
+	if (temperature <= -10)
+		factor10x = 170;
+	else if (temperature <= -5)
+		factor10x = 120;
+	else if (temperature <= 5)
+		factor10x = 80;
+	else if (temperature <= 10)
+		factor10x = 40;
+	else if (temperature <= 15)
+		factor10x = 30;
+	else if (temperature <= 20)
+		factor10x = 20;
+	else if (temperature <= 40)
+		factor10x = 10;
+	else
+		factor10x = 7;
+
+	epd->factored_stage_time = epd->stage_time * factor10x / 10;
+}
+
+static void repaper_gray8_to_mono_reversed(u8 *buf, u32 width, u32 height)
+{
+	u8 *gray8 = buf, *mono = buf;
+	int y, xb, i;
+
+	for (y = 0; y < height; y++)
+		for (xb = 0; xb < width / 8; xb++) {
+			u8 byte = 0x00;
+
+			for (i = 0; i < 8; i++) {
+				int x = xb * 8 + i;
+
+				byte >>= 1;
+				if (gray8[y * width + x] >> 7)
+					byte |= BIT(7);
+			}
+			*mono++ = byte;
+		}
+}
+
+static int repaper_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 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;
+	struct tinydrm_device *tdev = fb->dev->dev_private;
+	struct repaper_epd *epd = epd_from_tinydrm(tdev);
+	struct drm_clip_rect clip;
+	u8 *buf = NULL;
+	int ret = 0;
+
+	/* repaper can't do partial updates */
+	clip.x1 = 0;
+	clip.x2 = fb->width;
+	clip.y1 = 0;
+	clip.y2 = fb->height;
+
+	mutex_lock(&tdev->dirty_lock);
+
+	if (!epd->enabled)
+		goto out_unlock;
+
+	/* fbdev can flush even when we're not interested */
+	if (tdev->pipe.plane.fb != fb)
+		goto out_unlock;
+
+	repaper_get_temperature(epd);
+
+	DRM_DEBUG("Flushing [FB:%d] st=%ums\n", fb->base.id,
+		  epd->factored_stage_time);
+
+	buf = kmalloc(fb->width * fb->height, GFP_KERNEL);
+	if (!buf) {
+		ret = -ENOMEM;
+		goto out_unlock;
+	}
+
+	if (import_attach) {
+		ret = dma_buf_begin_cpu_access(import_attach->dmabuf,
+					       DMA_FROM_DEVICE);
+		if (ret)
+			goto out_unlock;
+	}
+
+	tinydrm_xrgb8888_to_gray8(buf, cma_obj->vaddr, fb, &clip);
+
+	if (import_attach) {
+		ret = dma_buf_end_cpu_access(import_attach->dmabuf,
+					     DMA_FROM_DEVICE);
+		if (ret)
+			goto out_unlock;
+	}
+
+	repaper_gray8_to_mono_reversed(buf, fb->width, fb->height);
+
+	if (epd->partial) {
+		repaper_frame_data_repeat(epd, buf, epd->current_frame,
+					  REPAPER_NORMAL);
+	} else if (epd->cleared) {
+		repaper_frame_data_repeat(epd, epd->current_frame, NULL,
+					  REPAPER_COMPENSATE);
+		repaper_frame_data_repeat(epd, epd->current_frame, NULL,
+					  REPAPER_WHITE);
+		repaper_frame_data_repeat(epd, buf, NULL, REPAPER_INVERSE);
+		repaper_frame_data_repeat(epd, buf, NULL, REPAPER_NORMAL);
+
+		epd->partial = true;
+	} else {
+		/* Clear display (anything -> white) */
+		repaper_frame_fixed_repeat(epd, 0xff, REPAPER_COMPENSATE);
+		repaper_frame_fixed_repeat(epd, 0xff, REPAPER_WHITE);
+		repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_INVERSE);
+		repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_NORMAL);
+
+		/* Assuming a clear (white) screen output an image */
+		repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_COMPENSATE);
+		repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_WHITE);
+		repaper_frame_data_repeat(epd, buf, NULL, REPAPER_INVERSE);
+		repaper_frame_data_repeat(epd, buf, NULL, REPAPER_NORMAL);
+
+		epd->cleared = true;
+		epd->partial = true;
+	}
+
+	memcpy(epd->current_frame, buf, fb->width * fb->height / 8);
+
+	/*
+	 * An extra frame write is needed if pixels are set in the bottom line,
+	 * or else grey lines rises up from the pixels
+	 */
+	if (epd->pre_border_byte) {
+		unsigned int x;
+
+		for (x = 0; x < (fb->width / 8); x++)
+			if (buf[x + (fb->width * (fb->height - 1) / 8)]) {
+				repaper_frame_data_repeat(epd, buf,
+							  epd->current_frame,
+							  REPAPER_NORMAL);
+				break;
+			}
+	}
+
+out_unlock:
+	mutex_unlock(&tdev->dirty_lock);
+
+	if (ret)
+		dev_err(fb->dev->dev, "Failed to update display (%d)\n", ret);
+	kfree(buf);
+
+	return ret;
+}
+
+static const struct drm_framebuffer_funcs repaper_fb_funcs = {
+	.destroy	= drm_fb_cma_destroy,
+	.create_handle	= drm_fb_cma_create_handle,
+	.dirty		= repaper_fb_dirty,
+};
+
+static void power_off(struct repaper_epd *epd)
+{
+	/* Turn off power and all signals */
+	gpiod_set_value_cansleep(epd->reset, 0);
+	gpiod_set_value_cansleep(epd->panel_on, 0);
+	if (epd->border)
+		gpiod_set_value_cansleep(epd->border, 0);
+
+	/* Ensure SPI MOSI and CLOCK are Low before CS Low */
+	repaper_spi_mosi_low(epd->spi);
+
+	/* Discharge pulse */
+	gpiod_set_value_cansleep(epd->discharge, 1);
+	msleep(150);
+	gpiod_set_value_cansleep(epd->discharge, 0);
+}
+
+static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe,
+				struct drm_crtc_state *crtc_state)
+{
+	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
+	struct repaper_epd *epd = epd_from_tinydrm(tdev);
+	struct spi_device *spi = epd->spi;
+	struct device *dev = &spi->dev;
+	bool dc_ok = false;
+	int i, ret;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	/* Power up sequence */
+	gpiod_set_value_cansleep(epd->reset, 0);
+	gpiod_set_value_cansleep(epd->panel_on, 0);
+	gpiod_set_value_cansleep(epd->discharge, 0);
+	if (epd->border)
+		gpiod_set_value_cansleep(epd->border, 0);
+	repaper_spi_mosi_low(spi);
+	usleep_range(5000, 10000);
+
+	gpiod_set_value_cansleep(epd->panel_on, 1);
+	/*
+	 * This delay comes from the repaper.org userspace driver, it's not
+	 * mentioned in the datasheet.
+	 */
+	usleep_range(10000, 15000);
+	gpiod_set_value_cansleep(epd->reset, 1);
+	if (epd->border)
+		gpiod_set_value_cansleep(epd->border, 1);
+	usleep_range(5000, 10000);
+	gpiod_set_value_cansleep(epd->reset, 0);
+	usleep_range(5000, 10000);
+	gpiod_set_value_cansleep(epd->reset, 1);
+	usleep_range(5000, 10000);
+
+	/* Wait for COG to become ready */
+	for (i = 100; i > 0; i--) {
+		if (!gpiod_get_value_cansleep(epd->busy))
+			break;
+
+		usleep_range(10, 100);
+	}
+
+	if (!i) {
+		dev_err(dev, "timeout waiting for panel to become ready.\n");
+		power_off(epd);
+		return;
+	}
+
+	repaper_read_id(spi);
+	ret = repaper_read_id(spi);
+	if (ret != REPAPER_RID_G2_COG_ID) {
+		if (ret < 0)
+			dev_err(dev, "failed to read chip (%d)\n", ret);
+		else
+			dev_err(dev, "wrong COG ID 0x%02x\n", ret);
+		power_off(epd);
+		return;
+	}
+
+	/* Disable OE */
+	repaper_write_val(spi, 0x02, 0x40);
+
+	ret = repaper_read_val(spi, 0x0f);
+	if (ret < 0 || !(ret & 0x80)) {
+		if (ret < 0)
+			dev_err(dev, "failed to read chip (%d)\n", ret);
+		else
+			dev_err(dev, "panel is reported broken\n");
+		power_off(epd);
+		return;
+	}
+
+	/* Power saving mode */
+	repaper_write_val(spi, 0x0b, 0x02);
+	/* Channel select */
+	repaper_write_buf(spi, 0x01, epd->channel_select, 8);
+	/* High power mode osc */
+	repaper_write_val(spi, 0x07, 0xd1);
+	/* Power setting */
+	repaper_write_val(spi, 0x08, 0x02);
+	/* Vcom level */
+	repaper_write_val(spi, 0x09, 0xc2);
+	/* Power setting */
+	repaper_write_val(spi, 0x04, 0x03);
+	/* Driver latch on */
+	repaper_write_val(spi, 0x03, 0x01);
+	/* Driver latch off */
+	repaper_write_val(spi, 0x03, 0x00);
+	usleep_range(5000, 10000);
+
+	/* Start chargepump */
+	for (i = 0; i < 4; ++i) {
+		/* Charge pump positive voltage on - VGH/VDL on */
+		repaper_write_val(spi, 0x05, 0x01);
+		msleep(240);
+
+		/* Charge pump negative voltage on - VGL/VDL on */
+		repaper_write_val(spi, 0x05, 0x03);
+		msleep(40);
+
+		/* Charge pump Vcom on - Vcom driver on */
+		repaper_write_val(spi, 0x05, 0x0f);
+		msleep(40);
+
+		/* check DC/DC */
+		ret = repaper_read_val(spi, 0x0f);
+		if (ret < 0) {
+			dev_err(dev, "failed to read chip (%d)\n", ret);
+			power_off(epd);
+			return;
+		}
+
+		if (ret & 0x40) {
+			dc_ok = true;
+			break;
+		}
+	}
+
+	if (!dc_ok) {
+		dev_err(dev, "dc/dc failed\n");
+		power_off(epd);
+		return;
+	}
+
+	/*
+	 * Output enable to disable
+	 * The userspace driver sets this to 0x04, but the datasheet says 0x06
+	 */
+	repaper_write_val(spi, 0x02, 0x04);
+
+	epd->enabled = true;
+	epd->partial = false;
+}
+
+static void repaper_pipe_disable(struct drm_simple_display_pipe *pipe)
+{
+	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
+	struct repaper_epd *epd = epd_from_tinydrm(tdev);
+	struct spi_device *spi = epd->spi;
+	unsigned int line;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	mutex_lock(&tdev->dirty_lock);
+	epd->enabled = false;
+	mutex_unlock(&tdev->dirty_lock);
+
+	/* Nothing frame */
+	for (line = 0; line < epd->height; line++)
+		repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL,
+				 REPAPER_COMPENSATE);
+
+	/* 2.7" */
+	if (epd->border) {
+		/* Dummy line */
+		repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL,
+				 REPAPER_COMPENSATE);
+		msleep(25);
+		gpiod_set_value_cansleep(epd->border, 0);
+		msleep(200);
+		gpiod_set_value_cansleep(epd->border, 1);
+	} else {
+		/* Border dummy line */
+		repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL,
+				 REPAPER_NORMAL);
+		msleep(200);
+	}
+
+	/* not described in datasheet */
+	repaper_write_val(spi, 0x0b, 0x00);
+	/* Latch reset turn on */
+	repaper_write_val(spi, 0x03, 0x01);
+	/* Power off charge pump Vcom */
+	repaper_write_val(spi, 0x05, 0x03);
+	/* Power off charge pump neg voltage */
+	repaper_write_val(spi, 0x05, 0x01);
+	msleep(120);
+	/* Discharge internal */
+	repaper_write_val(spi, 0x04, 0x80);
+	/* turn off all charge pumps */
+	repaper_write_val(spi, 0x05, 0x00);
+	/* Turn off osc */
+	repaper_write_val(spi, 0x07, 0x01);
+	msleep(50);
+
+	power_off(epd);
+}
+
+static const struct drm_simple_display_pipe_funcs repaper_pipe_funcs = {
+	.enable = repaper_pipe_enable,
+	.disable = repaper_pipe_disable,
+	.update = tinydrm_display_pipe_update,
+	.prepare_fb = tinydrm_display_pipe_prepare_fb,
+};
+
+static const uint32_t repaper_formats[] = {
+	DRM_FORMAT_XRGB8888,
+};
+
+static const struct drm_display_mode repaper_e1144cs021_mode = {
+	TINYDRM_MODE(128, 96, 29, 22),
+};
+
+static const u8 repaper_e1144cs021_cs[] = { 0x00, 0x00, 0x00, 0x00,
+					    0x00, 0x0f, 0xff, 0x00 };
+
+static const struct drm_display_mode repaper_e1190cs021_mode = {
+	TINYDRM_MODE(144, 128, 36, 32),
+};
+
+static const u8 repaper_e1190cs021_cs[] = { 0x00, 0x00, 0x00, 0x03,
+					    0xfc, 0x00, 0x00, 0xff };
+
+static const struct drm_display_mode repaper_e2200cs021_mode = {
+	TINYDRM_MODE(200, 96, 46, 22),
+};
+
+static const u8 repaper_e2200cs021_cs[] = { 0x00, 0x00, 0x00, 0x00,
+					    0x01, 0xff, 0xe0, 0x00 };
+
+static const struct drm_display_mode repaper_e2271cs021_mode = {
+	TINYDRM_MODE(264, 176, 57, 38),
+};
+
+static const u8 repaper_e2271cs021_cs[] = { 0x00, 0x00, 0x00, 0x7f,
+					    0xff, 0xfe, 0x00, 0x00 };
+
+DEFINE_DRM_GEM_CMA_FOPS(repaper_fops);
+
+static struct drm_driver repaper_driver = {
+	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_PRIME |
+				  DRIVER_ATOMIC,
+	.fops			= &repaper_fops,
+	TINYDRM_GEM_DRIVER_OPS,
+	.name			= "repaper",
+	.desc			= "Pervasive Displays RePaper e-ink panels",
+	.date			= "20170405",
+	.major			= 1,
+	.minor			= 0,
+};
+
+static const struct of_device_id repaper_of_match[] = {
+	{ .compatible = "pervasive,e1144cs021", .data = (void *)E1144CS021 },
+	{ .compatible = "pervasive,e1190cs021", .data = (void *)E1190CS021 },
+	{ .compatible = "pervasive,e2200cs021", .data = (void *)E2200CS021 },
+	{ .compatible = "pervasive,e2271cs021", .data = (void *)E2271CS021 },
+	{},
+};
+MODULE_DEVICE_TABLE(of, repaper_of_match);
+
+static const struct spi_device_id repaper_id[] = {
+	{ "e1144cs021", E1144CS021 },
+	{ "e1190cs021", E1190CS021 },
+	{ "e2200cs021", E2200CS021 },
+	{ "e2271cs021", E2271CS021 },
+	{ },
+};
+MODULE_DEVICE_TABLE(spi, repaper_id);
+
+static int repaper_probe(struct spi_device *spi)
+{
+	const struct drm_display_mode *mode;
+	const struct spi_device_id *spi_id;
+	const struct of_device_id *match;
+	struct device *dev = &spi->dev;
+	struct tinydrm_device *tdev;
+	enum repaper_model model;
+	const char *thermal_zone;
+	struct repaper_epd *epd;
+	size_t line_buffer_size;
+	int ret;
+
+	match = of_match_device(repaper_of_match, dev);
+	if (match) {
+		model = (enum repaper_model)match->data;
+	} else {
+		spi_id = spi_get_device_id(spi);
+		model = spi_id->driver_data;
+	}
+
+	/* The SPI device is used to allocate dma memory */
+	if (!dev->coherent_dma_mask) {
+		ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
+		if (ret) {
+			dev_warn(dev, "Failed to set dma mask %d\n", ret);
+			return ret;
+		}
+	}
+
+	epd = devm_kzalloc(dev, sizeof(*epd), GFP_KERNEL);
+	if (!epd)
+		return -ENOMEM;
+
+	epd->spi = spi;
+
+	epd->panel_on = devm_gpiod_get(dev, "panel-on", GPIOD_OUT_LOW);
+	if (IS_ERR(epd->panel_on)) {
+		ret = PTR_ERR(epd->panel_on);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get gpio 'panel-on'\n");
+		return ret;
+	}
+
+	epd->discharge = devm_gpiod_get(dev, "discharge", GPIOD_OUT_LOW);
+	if (IS_ERR(epd->discharge)) {
+		ret = PTR_ERR(epd->discharge);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get gpio 'discharge'\n");
+		return ret;
+	}
+
+	epd->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(epd->reset)) {
+		ret = PTR_ERR(epd->reset);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get gpio 'reset'\n");
+		return ret;
+	}
+
+	epd->busy = devm_gpiod_get(dev, "busy", GPIOD_IN);
+	if (IS_ERR(epd->busy)) {
+		ret = PTR_ERR(epd->busy);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get gpio 'busy'\n");
+		return ret;
+	}
+
+	if (!device_property_read_string(dev, "pervasive,thermal-zone",
+					 &thermal_zone)) {
+		epd->thermal = thermal_zone_get_zone_by_name(thermal_zone);
+		if (IS_ERR(epd->thermal)) {
+			dev_err(dev, "Failed to get thermal zone: %s\n",
+				thermal_zone);
+			return PTR_ERR(epd->thermal);
+		}
+	}
+
+	switch (model) {
+	case E1144CS021:
+		mode = &repaper_e1144cs021_mode;
+		epd->channel_select = repaper_e1144cs021_cs;
+		epd->stage_time = 480;
+		epd->bytes_per_scan = 96 / 4;
+		epd->middle_scan = true; /* data-scan-data */
+		epd->pre_border_byte = false;
+		epd->border_byte = REPAPER_BORDER_BYTE_ZERO;
+		break;
+
+	case E1190CS021:
+		mode = &repaper_e1190cs021_mode;
+		epd->channel_select = repaper_e1190cs021_cs;
+		epd->stage_time = 480;
+		epd->bytes_per_scan = 128 / 4 / 2;
+		epd->middle_scan = false; /* scan-data-scan */
+		epd->pre_border_byte = false;
+		epd->border_byte = REPAPER_BORDER_BYTE_SET;
+		break;
+
+	case E2200CS021:
+		mode = &repaper_e2200cs021_mode;
+		epd->channel_select = repaper_e2200cs021_cs;
+		epd->stage_time = 480;
+		epd->bytes_per_scan = 96 / 4;
+		epd->middle_scan = true; /* data-scan-data */
+		epd->pre_border_byte = true;
+		epd->border_byte = REPAPER_BORDER_BYTE_NONE;
+		break;
+
+	case E2271CS021:
+		epd->border = devm_gpiod_get(dev, "border", GPIOD_OUT_LOW);
+		if (IS_ERR(epd->border)) {
+			ret = PTR_ERR(epd->border);
+			if (ret != -EPROBE_DEFER)
+				dev_err(dev, "Failed to get gpio 'border'\n");
+			return ret;
+		}
+
+		mode = &repaper_e2271cs021_mode;
+		epd->channel_select = repaper_e2271cs021_cs;
+		epd->stage_time = 630;
+		epd->bytes_per_scan = 176 / 4;
+		epd->middle_scan = true; /* data-scan-data */
+		epd->pre_border_byte = true;
+		epd->border_byte = REPAPER_BORDER_BYTE_NONE;
+		break;
+
+	default:
+		return -ENODEV;
+	}
+
+	epd->width = mode->hdisplay;
+	epd->height = mode->vdisplay;
+	epd->factored_stage_time = epd->stage_time;
+
+	line_buffer_size = 2 * epd->width / 8 + epd->bytes_per_scan + 2;
+	epd->line_buffer = devm_kzalloc(dev, line_buffer_size, GFP_KERNEL);
+	if (!epd->line_buffer)
+		return -ENOMEM;
+
+	epd->current_frame = devm_kzalloc(dev, epd->width * epd->height / 8,
+					  GFP_KERNEL);
+	if (!epd->current_frame)
+		return -ENOMEM;
+
+	tdev = &epd->tinydrm;
+
+	ret = devm_tinydrm_init(dev, tdev, &repaper_fb_funcs, &repaper_driver);
+	if (ret)
+		return ret;
+
+	ret = tinydrm_display_pipe_init(tdev, &repaper_pipe_funcs,
+					DRM_MODE_CONNECTOR_VIRTUAL,
+					repaper_formats,
+					ARRAY_SIZE(repaper_formats), mode, 0);
+	if (ret)
+		return ret;
+
+	drm_mode_config_reset(tdev->drm);
+
+	ret = devm_tinydrm_register(tdev);
+	if (ret)
+		return ret;
+
+	spi_set_drvdata(spi, tdev);
+
+	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 repaper_shutdown(struct spi_device *spi)
+{
+	struct tinydrm_device *tdev = spi_get_drvdata(spi);
+
+	tinydrm_shutdown(tdev);
+}
+
+static struct spi_driver repaper_spi_driver = {
+	.driver = {
+		.name = "repaper",
+		.owner = THIS_MODULE,
+		.of_match_table = repaper_of_match,
+	},
+	.id_table = repaper_id,
+	.probe = repaper_probe,
+	.shutdown = repaper_shutdown,
+};
+module_spi_driver(repaper_spi_driver);
+
+MODULE_DESCRIPTION("Pervasive Displays RePaper DRM driver");
+MODULE_AUTHOR("Noralf Trønnes");
+MODULE_LICENSE("GPL");