From patchwork Thu Aug  3 22:33:48 2017
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
X-Patchwork-Submitter: David Lechner <david@lechnology.com>
X-Patchwork-Id: 9879993
Return-Path: 
 <linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org>
Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org
	[172.30.200.125])
	by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id
	1D03C60311 for <patchwork-linux-arm@patchwork.kernel.org>;
	Thu,  3 Aug 2017 22:36:55 +0000 (UTC)
Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1])
	by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0607026E74
	for <patchwork-linux-arm@patchwork.kernel.org>;
	Thu,  3 Aug 2017 22:36:55 +0000 (UTC)
Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486)
	id ED70C28974; Thu,  3 Aug 2017 22:36:54 +0000 (UTC)
X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on
	pdx-wl-mail.web.codeaurora.org
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00,DKIM_SIGNED,
	DKIM_VALID,RCVD_IN_DNSWL_NONE autolearn=unavailable version=3.3.1
Received: from bombadil.infradead.org (bombadil.infradead.org
	[65.50.211.133])
	(using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits))
	(No client certificate requested)
	by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 1F59026E74
	for <patchwork-linux-arm@patchwork.kernel.org>;
	Thu,  3 Aug 2017 22:36:54 +0000 (UTC)
DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed;
	d=lists.infradead.org; s=bombadil.20170209; h=Sender:
	Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe:
	List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References:
	In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID:
	Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc
	:Resent-Message-ID:List-Owner;
	bh=CA4Z2NeudyZMgL9dQsMsF/LKDVsoe+CNEftnl98PAdc=;
	b=a310o5mT89FJoyeQOOw/tJJP56
	8dSl1VWOcGIuWviw6O5f6Xv4nW+Tu7tihGItDrsggk3vNHo8ZPx9H3S2MVXxpFjXI38PensWG8MG0
	o0QoS4LG0Qa1mKrMvAtX8CTBjTdvnw5qNNkrDOrgKKCO8fzzkQZUtDA7ijV/Vt9E32fA3TSkd+cf2
	Lte0BTy5cDL8fs9oT0X6kY1mcr+mMhIt11J/jSOrZJ8VfY5q1fOp0P8BFxrpza9OxmeS/rFjfu5gP
	zCCmRkz+EI3yWpUUGd3ZcKvx9QlPGTMqJtWsDL5m2ClSX3z+n+ZRdH6OTRO3PJU2DQeJ+vHM6p0i6
	+QGIZ/Zw==;
Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org)
	by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux))
	id 1ddOjb-0001hB-B3; Thu, 03 Aug 2017 22:36:51 +0000
Received: from casper.infradead.org ([2001:8b0:10b:1236::1])
	by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux))
	id 1ddOi1-0000WC-Pn for linux-arm-kernel@bombadil.infradead.org;
	Thu, 03 Aug 2017 22:35:14 +0000
DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed;
	d=infradead.org; s=casper.20170209;
	h=References:In-Reply-To:Message-Id:Date:
	Subject:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type:
	Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:
	Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:
	List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive;
	bh=gTTLfAcfV4fXPwAg4KStRoOKF2ayOosUbtuAdy5uJxQ=;
	b=kPvOnEG5CTtho3fZng+MMgs8D
	p1wCWoKnvTCoipY31rCkROOViVYEF0MJIxL6patPpGDS/UgOcfc5++7Rf1WKVrd9h4QgEUEX0kST5
	+nsT2MkCtWuamrRG6KriNVold6vsX4jCFhKf4v6sWbevLniEMgwqrW/QU2vi7u+KIR22Mt5tig4oM
	rcfLYzI+JDXIt6KH5mVLXcXyb1xdXkLdyHV22YChF7qspqY7QqWLCRkdb6x1lCueB+eZ+L67nqFE+
	ikMreFg7NREHCnVV+k16Jo/G2IzpQ7h3DRZlCXWJM2u1a/2q0M0HLuFiRUE6Q/W01u9budJO7FCY2
	JIlsjZdCg==;
Received: from vern.gendns.com ([206.190.152.46])
	by casper.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux))
	id 1ddOhv-0001eq-TE for linux-arm-kernel@lists.infradead.org;
	Thu, 03 Aug 2017 22:35:12 +0000
DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed;
	d=lechnology.com; s=default;
	h=References:In-Reply-To:Message-Id:Date:Subject
	:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type:
	Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:
	Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:
	List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive;
	bh=gTTLfAcfV4fXPwAg4KStRoOKF2ayOosUbtuAdy5uJxQ=;
	b=OTqmwuAt1CQnTZHYf8hSPX8Lc
	SFIZzAFFdUBj5ECwmnmSljFRatymnti4wF6b9d4fGWr4LBteBjhYXQTr9maN9QTxvyv7jZZZCAbyR
	Hh1aNzXUqxz+PBG0bhQFQXFb2dZ0Qe9IC2gUoYaioZeA2hx3BCC7ozli1BSwFwEgQMpwaGrXH3DfK
	SxAp0UpAeTtaAQx6bvqCHK+6SL5UaeVTu0vk5xHiDdierci3JSfe83nEJsMAayVrn1V3jXAN1mGTL
	QXpWY8cjWNlsxuHFe/2FPXeH/7tFRkUDLPchmWbF0Svh0i5MDNa7MjVQSIK452i6IJzCioHXHhHRB
	QvJbIMPtw==;
Received: from 108-198-5-147.lightspeed.okcbok.sbcglobal.net
	([108.198.5.147]:57234 helo=freyr.lechnology.com)
	by vern.gendns.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-SHA256:128)
	(Exim 4.89) (envelope-from <david@lechnology.com>)
	id 1ddOeC-000kyM-AO; Thu, 03 Aug 2017 18:31:16 -0400
From: David Lechner <david@lechnology.com>
To: dri-devel@lists.freedesktop.org,
	devicetree@vger.kernel.org
Subject: [PATCH v3 4/6] drm/tinydrm: add support for LEGO MINDSTORMS EV3 LCD
Date: Thu,  3 Aug 2017 17:33:48 -0500
Message-Id: <1501799630-1650-5-git-send-email-david@lechnology.com>
X-Mailer: git-send-email 2.7.4
In-Reply-To: <1501799630-1650-1-git-send-email-david@lechnology.com>
References: <1501799630-1650-1-git-send-email-david@lechnology.com>
X-AntiAbuse: This header was added to track abuse,
	please include it with any abuse report
X-AntiAbuse: Primary Hostname - vern.gendns.com
X-AntiAbuse: Original Domain - lists.infradead.org
X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12]
X-AntiAbuse: Sender Address Domain - lechnology.com
X-Get-Message-Sender-Via: vern.gendns.com: authenticated_id:
	davidmain+lechnology.com/only user confirmed/virtual account not
	confirmed
X-Authenticated-Sender: vern.gendns.com: davidmain@lechnology.com
X-Source: 
X-Source-Args: 
X-Source-Dir: 
X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 
X-CRM114-CacheID: sfid-20170803_233508_289771_35F7CF77 
X-CRM114-Status: GOOD (  28.03  )
X-BeenThere: linux-arm-kernel@lists.infradead.org
X-Mailman-Version: 2.1.21
Precedence: list
List-Id: <linux-arm-kernel.lists.infradead.org>
List-Unsubscribe: 
 <http://lists.infradead.org/mailman/options/linux-arm-kernel>,
	<mailto:linux-arm-kernel-request@lists.infradead.org?subject=unsubscribe>
List-Archive: <http://lists.infradead.org/pipermail/linux-arm-kernel/>
List-Post: <mailto:linux-arm-kernel@lists.infradead.org>
List-Help: <mailto:linux-arm-kernel-request@lists.infradead.org?subject=help>
List-Subscribe: 
 <http://lists.infradead.org/mailman/listinfo/linux-arm-kernel>,
	<mailto:linux-arm-kernel-request@lists.infradead.org?subject=subscribe>
Cc: Mark Rutland <mark.rutland@arm.com>,
	=?UTF-8?q?Noralf=20Tr=C3=B8nnes?= <noralf@tronnes.org>,
	David Lechner <david@lechnology.com>, Kevin Hilman <khilman@kernel.org>,
	David Airlie <airlied@linux.ie>, Sekhar Nori <nsekhar@ti.com>,
	linux-kernel@vger.kernel.org, Rob Herring <robh+dt@kernel.org>,
	Daniel Vetter <daniel@ffwll.ch>, linux-arm-kernel@lists.infradead.org
MIME-Version: 1.0
Sender: "linux-arm-kernel" <linux-arm-kernel-bounces@lists.infradead.org>
Errors-To: 
 linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org
X-Virus-Scanned: ClamAV using ClamSMTP

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>
---
 MAINTAINERS                      |   6 +
 drivers/gpu/drm/tinydrm/Kconfig  |  10 +
 drivers/gpu/drm/tinydrm/Makefile |   1 +
 drivers/gpu/drm/tinydrm/st7586.c | 466 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 483 insertions(+)
 create mode 100644 drivers/gpu/drm/tinydrm/st7586.c

diff --git a/MAINTAINERS b/MAINTAINERS
index a1e772e..9643f95 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4365,6 +4365,12 @@ S:	Maintained
 F:	drivers/gpu/drm/tinydrm/repaper.c
 F:	Documentation/devicetree/bindings/display/repaper.txt
 
+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 RAGE 128 VIDEO CARDS
 S:	Orphan / Obsolete
 F:	drivers/gpu/drm/r128/
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..11e226d
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/st7586.c
@@ -0,0 +1,466 @@
+/*
+ * 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/regulator/consumer.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)
+
+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;
+
+	/* 3 pixels per byte, so grow clip to nearest multiple of 3 */
+	clip->x1 = clip->x1 / 3 * 3;
+	clip->x2 = (clip->x2 + 2) / 3 * 3;
+
+	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 = *src++ & 0xc0;
+			if (val & 0xc0)
+				val |= 0x20;
+			val |= (*src++ & 0xc0) >> 3;
+			if (val & 0x18)
+				val |= 0x04;
+			val |= *src++ >> 6;
+			*dst++ = ~val;
+		}
+	}
+
+	/* now adjust the clip so it applies to dst */
+	clip->x1 /= 3;
+	clip->x2 /= 3;
+
+	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;
+	struct drm_format_name_buf format_name;
+	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;
+	}
+
+	switch (fb->format->format) {
+	case DRM_FORMAT_XRGB8888:
+		st7586_xrgb8888_to_gray332(dst, src, fb, clip);
+		break;
+	default:
+		dev_err_once(fb->dev->dev, "Format is not supported: %s\n",
+			     drm_get_format_name(fb->format->format,
+						 &format_name));
+		ret = -EINVAL;
+		break;
+	}
+
+	if (import_attach)
+		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 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);
+
+	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;
+
+	/* NB: st7586_buf_copy() modifies clip */
+
+	mipi_dbi_command(mipi, MIPI_DCS_SET_COLUMN_ADDRESS,
+			 (clip.x1 >> 8) & 0xFF, clip.x1 & 0xFF,
+			 (clip.x2 >> 8) & 0xFF, (clip.x2 - 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,
+				   (clip.x2 - clip.x1) * (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");
+
+	ret = regulator_enable(mipi->regulator);
+	if (ret) {
+		dev_err(dev, "Failed to enable regulator %d\n", ret);
+		return;
+	}
+
+	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);
+		regulator_disable(mipi->regulator);
+		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);
+
+	tinydrm_enable_backlight(mipi->backlight);
+}
+
+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->enabled = false;
+	tinydrm_disable_backlight(mipi->backlight);
+	mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_OFF);
+	regulator_disable(mipi->regulator);
+}
+
+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 *dc;
+	u32 rotation = 0;
+	int ret;
+
+	mipi = devm_kzalloc(dev, sizeof(*mipi), GFP_KERNEL);
+	if (!mipi)
+		return -ENOMEM;
+
+	mipi->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(mipi->reset)) {
+		dev_err(dev, "Failed to get gpio 'reset'\n");
+		return PTR_ERR(mipi->reset);
+	}
+
+	dc = devm_gpiod_get_optional(dev, "dc", GPIOD_OUT_LOW);
+	if (IS_ERR(dc)) {
+		dev_err(dev, "Failed to get gpio 'dc'\n");
+		return PTR_ERR(dc);
+	}
+
+	mipi->regulator = devm_regulator_get(dev, "power");
+	if (IS_ERR(mipi->regulator))
+		return PTR_ERR(mipi->regulator);
+
+	mipi->backlight = tinydrm_of_find_backlight(dev);
+	if (IS_ERR(mipi->backlight))
+		return PTR_ERR(mipi->backlight);
+
+	device_property_read_u32(dev, "rotation", &rotation);
+
+	ret = mipi_dbi_spi_init(spi, mipi, dc);
+	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 int __maybe_unused st7586_pm_suspend(struct device *dev)
+{
+	struct mipi_dbi *mipi = dev_get_drvdata(dev);
+
+	return tinydrm_suspend(&mipi->tinydrm);
+}
+
+static int __maybe_unused st7586_pm_resume(struct device *dev)
+{
+	struct mipi_dbi *mipi = dev_get_drvdata(dev);
+
+	return tinydrm_resume(&mipi->tinydrm);
+}
+
+static const struct dev_pm_ops st7586_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(st7586_pm_suspend, st7586_pm_resume)
+};
+
+static struct spi_driver st7586_spi_driver = {
+	.driver = {
+		.name = "st7586",
+		.owner = THIS_MODULE,
+		.of_match_table = st7586_of_match,
+		.pm = &st7586_pm_ops,
+	},
+	.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");