From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <devicetree-owner@kernel.org>
X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on
	aws-us-west-2-korg-lkml-1.web.codeaurora.org
Received: from vger.kernel.org (vger.kernel.org [23.128.96.18])
	by smtp.lore.kernel.org (Postfix) with ESMTP id 81A55C4708D
	for <linux-devicetree@archiver.kernel.org>; Thu, 15 Dec 2022 18:52:34 +0000 (UTC)
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S230447AbiLOSwd (ORCPT
        <rfc822;linux-devicetree@archiver.kernel.org>);
        Thu, 15 Dec 2022 13:52:33 -0500
Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46956 "EHLO
        lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S230450AbiLOSw0 (ORCPT
        <rfc822;devicetree@vger.kernel.org>); Thu, 15 Dec 2022 13:52:26 -0500
Received: from mail-oa1-x2c.google.com (mail-oa1-x2c.google.com [IPv6:2001:4860:4864:20::2c])
        by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA087419BE
        for <devicetree@vger.kernel.org>; Thu, 15 Dec 2022 10:52:21 -0800 (PST)
Received: by mail-oa1-x2c.google.com with SMTP id 586e51a60fabf-1442977d77dso421571fac.6
        for <devicetree@vger.kernel.org>; Thu, 15 Dec 2022 10:52:21 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=gmail.com; s=20210112;
        h=content-transfer-encoding:mime-version:references:in-reply-to
         :message-id:date:subject:cc:to:from:from:to:cc:subject:date
         :message-id:reply-to;
        bh=DPCglAEbRJpSIj0IExAJLedLOzM/yqHo7P3ZSPUs9oo=;
        b=LGXn66bUmiYQBni+DUI6/iYoDeN/AXKfYqHH0aE6bQy6PC0aRFyWmowcz8FJj1SeYX
         l60O25Z57EVwwBktkfdU6qyRDjKAMQ0uk57FW6t4izJuWwtN4e1yQFHIjV/6NhwRsWMM
         ZLB5+dpiGYye7ruxkrKZpP4ykpk1pRKErt5HXy1whQriS+dxZCBrzA0gE1C1XjgSQFQD
         1ASEanzgXXqv3aRwljDpY6V7Hi3DfWLS/xISHqmEEySRY198fAPf4LmSsW04OvnYC6w6
         EhRgrwL1LcRZEXnDgYzNjTPQR1xTR2pv1pKZkompGRCVxDmuj2Cts3KcXCYHYacOdGFg
         RY1g==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=1e100.net; s=20210112;
        h=content-transfer-encoding:mime-version:references:in-reply-to
         :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc
         :subject:date:message-id:reply-to;
        bh=DPCglAEbRJpSIj0IExAJLedLOzM/yqHo7P3ZSPUs9oo=;
        b=LzVmstGEQdoEumFCAtJEUFrq6Z3MwI+Y5vS8/VbwWuOjm3rxpPg3SSbBOUYhz9axv5
         lnHyj/a81MqGU/HlG3WGMvYCIXeyfGxX0K6uuX9Auuze3AVPApdFMV8GncxBs9+P+fHI
         oaC9fzqSbwPfCPqGaZ4FCbD6sovo6TPasIzMNKnBacukW+epWOoWHr9/B2TMHQ9lYYNG
         sv2izf2WeuDmlSQsmN/QmWerR3PzAUsvW4nBrvQV/mS4yIL75yvXJLsKut+k1cmxprZ+
         q6s3yvqTiW+YYnRqho7cqoyEH3ZFtha+7VCJ52fVK4yaaHQpTnHape2ufZE+knSMxqBD
         KZvQ==
X-Gm-Message-State: ANoB5pnFfF8lFETDocDqed21I0cYda8REdVuC/rc7AXSIlm0emXDx6FA
        T7khGTR9wKdXv8IjnFDOSDg=
X-Google-Smtp-Source: AA0mqf4Iao9iuhUieQ1Fa6p/ftvl03foqbmcCxZwdLImqObZQ8V347h4jS31HVTe44oBLEWHFZJjBQ==
X-Received: by 2002:a05:6870:2420:b0:144:77eb:7a7 with SMTP id n32-20020a056870242000b0014477eb07a7mr14920383oap.47.1671130340770;
        Thu, 15 Dec 2022 10:52:20 -0800 (PST)
Received: from localhost.localdomain ([76.244.6.13])
        by smtp.gmail.com with ESMTPSA id g11-20020a4ad84b000000b004a09df5a1dbsm72264oov.8.2022.12.15.10.52.19
        (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256);
        Thu, 15 Dec 2022 10:52:20 -0800 (PST)
From:   Chris Morgan <macroalpha82@gmail.com>
To:     dri-devel@lists.freedesktop.org
Cc:     devicetree@vger.kernel.org, maccraft123mc@gmail.com,
        tzimmermann@suse.de, mripard@kernel.org,
        maarten.lankhorst@linux.intel.com, heiko@sntech.de,
        linux-rockchip@lists.infradead.org,
        krzysztof.kozlowski+dt@linaro.org, robh+dt@kernel.org,
        daniel@ffwll.ch, airlied@gmail.com, sam@ravnborg.org,
        thierry.reding@gmail.com, linus.walleij@linaro.org,
        Chris Morgan <macromorgan@hotmail.com>
Subject: [PATCH V6 3/4] drm/panel: Add Magnachip D53E6EA8966 Panel Driver
Date:   Thu, 15 Dec 2022 12:52:10 -0600
Message-Id: <20221215185211.1560736-4-macroalpha82@gmail.com>
X-Mailer: git-send-email 2.34.1
In-Reply-To: <20221215185211.1560736-1-macroalpha82@gmail.com>
References: <20221215185211.1560736-1-macroalpha82@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk
List-ID: <devicetree.vger.kernel.org>
X-Mailing-List: devicetree@vger.kernel.org

From: Chris Morgan <macromorgan@hotmail.com>

Support Magnachip D53E6EA8966 based panels such as the Samsung
AMS495QA01 panel as found on the Anbernic RG503. Note this driver
supports only the AMS495QA01 today which receives video signals via DSI,
however it receives commands via 3-wire SPI using DBI.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/gpu/drm/panel/Kconfig                 |  11 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 .../drm/panel/panel-magnachip-d53e6ea8966.c   | 514 ++++++++++++++++++
 3 files changed, 526 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 737edcdf9eef..2aa73f8aeef3 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -298,6 +298,17 @@ config DRM_PANEL_LG_LG4573
 	  Say Y here if you want to enable support for LG4573 RGB panel.
 	  To compile this driver as a module, choose M here.
 
+config DRM_PANEL_MAGNACHIP_D53E6EA8966
+	tristate "Magnachip D53E6EA8966 DSI panel"
+	depends on OF && SPI
+	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
+	select DRM_MIPI_DBI
+	help
+	  DRM panel driver for the Samsung AMS495QA01 panel controlled
+	  with the Magnachip D53E6EA8966 panel IC. This panel receives
+	  video data via DSI but commands via 9-bit SPI using DBI.
+
 config DRM_PANEL_NEC_NL8048HL11
 	tristate "NEC NL8048HL11 RGB panel"
 	depends on GPIOLIB && OF && SPI
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index f8f9d9f6a307..20de312aa5e9 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK050H3146W) += panel-leadtek-ltk050h3146w.o
 obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK500HD1829) += panel-leadtek-ltk500hd1829.o
 obj-$(CONFIG_DRM_PANEL_LG_LB035Q02) += panel-lg-lb035q02.o
 obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o
+obj-$(CONFIG_DRM_PANEL_MAGNACHIP_D53E6EA8966) += panel-magnachip-d53e6ea8966.o
 obj-$(CONFIG_DRM_PANEL_NEC_NL8048HL11) += panel-nec-nl8048hl11.o
 obj-$(CONFIG_DRM_PANEL_NEWVISION_NV3051D) += panel-newvision-nv3051d.o
 obj-$(CONFIG_DRM_PANEL_NEWVISION_NV3052C) += panel-newvision-nv3052c.o
diff --git a/drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c b/drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c
new file mode 100644
index 000000000000..ec90da8e2ae7
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c
@@ -0,0 +1,514 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Magnachip d53e6ea8966 MIPI-DSI panel driver
+ * Copyright (C) 2022 Chris Morgan
+ */
+
+#include <drm/drm_mipi_dbi.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/media-bus-format.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+
+#include <video/mipi_display.h>
+
+/* Forward declaration for use in backlight function */
+struct d53e6ea8966;
+
+/* Panel info, unique to each panel */
+struct d53e6ea8966_panel_info {
+	/** @display_modes: the supported display modes */
+	const struct drm_display_mode *display_modes;
+	/** @num_modes: the number of supported display modes */
+	unsigned int num_modes;
+	/** @width_mm: panel width in mm */
+	u16 width_mm;
+	/** @height_mm: panel height in mm */
+	u16 height_mm;
+	/** @bus_flags: drm bus flags for panel */
+	u32 bus_flags;
+	/** @panel_funcs: panel functions for panel */
+	const struct drm_panel_funcs *panel_funcs;
+	/** @backlight: panel backlight registration or NULL */
+	int (*backlight_register)(struct d53e6ea8966 *db);
+};
+
+struct d53e6ea8966 {
+	/** @dev: the container device */
+	struct device *dev;
+	/** @dbi: the DBI bus abstraction handle */
+	struct mipi_dbi dbi;
+	/** @panel: the DRM panel instance for this device */
+	struct drm_panel panel;
+	/** @reset: reset GPIO line */
+	struct gpio_desc *reset;
+	/** @enable: enable GPIO line */
+	struct gpio_desc *enable;
+	/** @reg_vdd: VDD supply regulator for panel logic */
+	struct regulator *reg_vdd;
+	/** @reg_elvdd: ELVDD supply regulator for panel display */
+	struct regulator *reg_elvdd;
+	/** @dsi_dev: DSI child device (panel) */
+	struct mipi_dsi_device *dsi_dev;
+	/** @bl_dev: pseudo-backlight device for oled panel */
+	struct backlight_device *bl_dev;
+	/** @panel_info: struct containing panel timing and info */
+	const struct d53e6ea8966_panel_info *panel_info;
+};
+
+#define NUM_GAMMA_LEVELS	16
+#define GAMMA_TABLE_COUNT	23
+#define MAX_BRIGHTNESS		(NUM_GAMMA_LEVELS - 1)
+
+#define MCS_ELVSS_ON			0xb1
+#define MCS_TEMP_SWIRE			0xb2
+#define MCS_PASSWORD_0			0xf0
+#define MCS_PASSWORD_1			0xf1
+#define MCS_ANALOG_PWR_CTL_0		0xf4
+#define MCS_ANALOG_PWR_CTL_1		0xf5
+#define MCS_GTCON_SET			0xf7
+#define MCS_GATELESS_SIGNAL_SET		0xf8
+#define MCS_SET_GAMMA			0xf9
+
+static inline struct d53e6ea8966 *to_d53e6ea8966(struct drm_panel *panel)
+{
+	return container_of(panel, struct d53e6ea8966, panel);
+}
+
+/* Table of gamma values provided in datasheet */
+static u8 ams495qa01_gamma[NUM_GAMMA_LEVELS][GAMMA_TABLE_COUNT] = {
+	{0x01, 0x79, 0x78, 0x8d, 0xd9, 0xdf, 0xd5, 0xcb, 0xcf, 0xc5,
+	 0xe5, 0xe0, 0xe4, 0xdc, 0xb8, 0xd4, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x7d, 0x7c, 0x92, 0xd7, 0xdd, 0xd2, 0xcb, 0xd0, 0xc6,
+	 0xe5, 0xe1, 0xe3, 0xda, 0xbd, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x7f, 0x7e, 0x95, 0xd7, 0xde, 0xd2, 0xcb, 0xcf, 0xc5,
+	 0xe5, 0xe3, 0xe3, 0xda, 0xbf, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x82, 0x81, 0x99, 0xd6, 0xdd, 0xd1, 0xca, 0xcf, 0xc3,
+	 0xe4, 0xe3, 0xe3, 0xda, 0xc2, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x84, 0x83, 0x9b, 0xd7, 0xde, 0xd2, 0xc8, 0xce, 0xc2,
+	 0xe4, 0xe3, 0xe2, 0xd9, 0xc3, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x87, 0x86, 0x9f, 0xd6, 0xdd, 0xd1, 0xc7, 0xce, 0xc1,
+	 0xe4, 0xe3, 0xe2, 0xd9, 0xc6, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x89, 0x89, 0xa2, 0xd5, 0xdb, 0xcf, 0xc8, 0xcf, 0xc2,
+	 0xe3, 0xe3, 0xe1, 0xd9, 0xc7, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x8b, 0x8b, 0xa5, 0xd5, 0xdb, 0xcf, 0xc7, 0xce, 0xc0,
+	 0xe3, 0xe3, 0xe1, 0xd8, 0xc7, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x8d, 0x8d, 0xa7, 0xd5, 0xdb, 0xcf, 0xc6, 0xce, 0xc0,
+	 0xe4, 0xe4, 0xe1, 0xd7, 0xc8, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x8f, 0x8f, 0xaa, 0xd4, 0xdb, 0xce, 0xc6, 0xcd, 0xbf,
+	 0xe3, 0xe3, 0xe1, 0xd7, 0xca, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x91, 0x91, 0xac, 0xd3, 0xda, 0xce, 0xc5, 0xcd, 0xbe,
+	 0xe3, 0xe3, 0xe0, 0xd7, 0xca, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x93, 0x93, 0xaf, 0xd3, 0xda, 0xcd, 0xc5, 0xcd, 0xbe,
+	 0xe2, 0xe3, 0xdf, 0xd6, 0xca, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x95, 0x95, 0xb1, 0xd2, 0xd9, 0xcc, 0xc4, 0xcd, 0xbe,
+	 0xe2, 0xe3, 0xdf, 0xd7, 0xcc, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x99, 0x99, 0xb6, 0xd1, 0xd9, 0xcc, 0xc3, 0xcb, 0xbc,
+	 0xe2, 0xe4, 0xdf, 0xd6, 0xcc, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x9c, 0x9c, 0xba, 0xd0, 0xd8, 0xcb, 0xc3, 0xcb, 0xbb,
+	 0xe2, 0xe4, 0xdf, 0xd6, 0xce, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x9f, 0x9f, 0xbe, 0xcf, 0xd7, 0xc9, 0xc2, 0xcb, 0xbb,
+	 0xe1, 0xe3, 0xde, 0xd6, 0xd0, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+};
+
+/*
+ * Table of elvss values provided in datasheet and corresponds to
+ * gamma values.
+ */
+static u8 ams495qa01_elvss[NUM_GAMMA_LEVELS] = {
+	0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15,
+	0x15, 0x15, 0x14, 0x14, 0x13, 0x12,
+};
+
+static int ams495qa01_update_gamma(struct mipi_dbi *dbi, u32 brightness)
+{
+	u32 tmp = brightness;
+
+	mipi_dbi_command_buf(dbi, MCS_SET_GAMMA, ams495qa01_gamma[tmp],
+			     ARRAY_SIZE(ams495qa01_gamma[tmp]));
+	mipi_dbi_command(dbi, MCS_SET_GAMMA, 0x00);
+
+	/* Undocumented command */
+	mipi_dbi_command(dbi, 0x26, 0x00);
+
+	mipi_dbi_command(dbi, MCS_TEMP_SWIRE, ams495qa01_elvss[tmp]);
+
+	return 0;
+}
+
+static int ams495qa01_prepare(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	struct mipi_dbi *dbi = &db->dbi;
+	int ret;
+
+	/* Power up */
+	ret = regulator_enable(db->reg_vdd);
+	if (ret) {
+		dev_err(db->dev, "failed to enable vdd regulator: %d\n", ret);
+		return ret;
+	}
+
+	if (db->reg_elvdd) {
+		ret = regulator_enable(db->reg_elvdd);
+		if (ret) {
+			dev_err(db->dev,
+				"failed to enable elvdd regulator: %d\n", ret);
+			regulator_disable(db->reg_vdd);
+			return ret;
+		}
+	}
+
+	/* Enable */
+	if (db->enable)
+		gpiod_set_value_cansleep(db->enable, 1);
+
+	msleep(50);
+
+	/* Reset */
+	gpiod_set_value_cansleep(db->reset, 1);
+	usleep_range(1000, 5000);
+	gpiod_set_value_cansleep(db->reset, 0);
+	msleep(20);
+
+	/* Panel Init Sequence */
+
+	mipi_dbi_command(dbi, MCS_PASSWORD_0, 0x5a, 0x5a);
+	mipi_dbi_command(dbi, MCS_PASSWORD_1, 0x5a, 0x5a);
+	/* Undocumented commands */
+	mipi_dbi_command(dbi, 0xb0, 0x02);
+	mipi_dbi_command(dbi, 0xf3, 0x3b);
+
+	mipi_dbi_command(dbi, MCS_ANALOG_PWR_CTL_0, 0x33, 0x42, 0x00, 0x08);
+	mipi_dbi_command(dbi, MCS_ANALOG_PWR_CTL_1, 0x00, 0x06, 0x26, 0x35, 0x03);
+
+	/* Undocumented commands */
+	mipi_dbi_command(dbi, 0xf6, 0x02);
+	mipi_dbi_command(dbi, 0xc6, 0x0b, 0x00, 0x00, 0x3c, 0x00, 0x22,
+			 0x00, 0x00, 0x00, 0x00);
+
+	mipi_dbi_command(dbi, MCS_GTCON_SET, 0x20);
+	mipi_dbi_command(dbi, MCS_TEMP_SWIRE, 0x06, 0x06, 0x06, 0x06);
+	mipi_dbi_command(dbi, MCS_ELVSS_ON, 0x07, 0x00, 0x10);
+	mipi_dbi_command(dbi, MCS_GATELESS_SIGNAL_SET, 0x7f, 0x7a,
+			 0x89, 0x67, 0x26, 0x38, 0x00, 0x00, 0x09,
+			 0x67, 0x70, 0x88, 0x7a, 0x76, 0x05, 0x09,
+			 0x23, 0x23, 0x23);
+
+	/* Undocumented commands */
+	mipi_dbi_command(dbi, 0xb5, 0xff, 0xef, 0x35, 0x42, 0x0d, 0xd7,
+			 0xff, 0x07, 0xff, 0xff, 0xfd, 0x00, 0x01,
+			 0xff, 0x05, 0x12, 0x0f, 0xff, 0xff, 0xff,
+			 0xff);
+	mipi_dbi_command(dbi, 0xb4, 0x15);
+	mipi_dbi_command(dbi, 0xb3, 0x00);
+
+	ams495qa01_update_gamma(dbi, MAX_BRIGHTNESS);
+
+	return 0;
+}
+
+static int ams495qa01_enable(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	struct mipi_dbi *dbi = &db->dbi;
+
+	mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
+	msleep(200);
+	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
+	usleep_range(10000, 15000);
+
+	return 0;
+}
+
+static int ams495qa01_disable(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	struct mipi_dbi *dbi = &db->dbi;
+
+	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_OFF);
+	msleep(20);
+	mipi_dbi_command(dbi, MIPI_DCS_ENTER_SLEEP_MODE);
+	msleep(100);
+
+	return 0;
+}
+
+static int ams495qa01_unprepare(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+
+	if (db->enable)
+		gpiod_set_value_cansleep(db->enable, 0);
+
+	gpiod_set_value_cansleep(db->reset, 1);
+
+	if (db->reg_elvdd)
+		regulator_disable(db->reg_elvdd);
+
+	regulator_disable(db->reg_vdd);
+	msleep(100);
+
+	return 0;
+}
+
+static int ams495qa01_get_modes(struct drm_panel *panel,
+				struct drm_connector *connector)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	const struct d53e6ea8966_panel_info *panel_info = db->panel_info;
+	struct drm_display_mode *mode;
+	static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	unsigned int i;
+
+	for (i = 0; i < panel_info->num_modes; i++) {
+		mode = drm_mode_duplicate(connector->dev,
+					  &panel_info->display_modes[i]);
+		if (!mode)
+			return -ENOMEM;
+
+		drm_mode_set_name(mode);
+		drm_mode_probed_add(connector, mode);
+	}
+
+	connector->display_info.bpc = 8;
+	connector->display_info.width_mm = panel_info->width_mm;
+	connector->display_info.height_mm = panel_info->height_mm;
+	connector->display_info.bus_flags = panel_info->bus_flags;
+
+	drm_display_info_set_bus_formats(&connector->display_info,
+					 &bus_format, 1);
+
+	return 1;
+}
+
+static const struct drm_panel_funcs ams495qa01_panel_funcs = {
+	.disable = ams495qa01_disable,
+	.enable = ams495qa01_enable,
+	.get_modes = ams495qa01_get_modes,
+	.prepare = ams495qa01_prepare,
+	.unprepare = ams495qa01_unprepare,
+};
+
+static int ams495qa01_set_brightness(struct backlight_device *bd)
+{
+	struct d53e6ea8966 *db = bl_get_data(bd);
+	struct mipi_dbi *dbi = &db->dbi;
+	int brightness = bd->props.brightness;
+
+	ams495qa01_update_gamma(dbi, brightness);
+
+	return 0;
+}
+
+static const struct backlight_ops ams495qa01_backlight_ops = {
+	.update_status	= ams495qa01_set_brightness,
+};
+
+static int ams495qa01_backlight_register(struct d53e6ea8966 *db)
+{
+	struct backlight_properties props = {
+		.type		= BACKLIGHT_RAW,
+		.brightness	= MAX_BRIGHTNESS,
+		.max_brightness = MAX_BRIGHTNESS,
+	};
+	struct device *dev = db->dev;
+	int ret = 0;
+
+	db->bl_dev = devm_backlight_device_register(dev, "panel", dev, db,
+						     &ams495qa01_backlight_ops,
+						     &props);
+	if (IS_ERR(db->bl_dev)) {
+		ret = PTR_ERR(db->bl_dev);
+		dev_err(dev, "error registering backlight device (%d)\n", ret);
+	}
+
+	return ret;
+}
+
+static int d53e6ea8966_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct mipi_dsi_host *dsi_host;
+	struct d53e6ea8966 *db;
+	int ret;
+	struct mipi_dsi_device_info info = {
+		.type = "d53e6ea8966",
+		.channel = 0,
+		.node = NULL,
+	};
+
+	db = devm_kzalloc(dev, sizeof(*db), GFP_KERNEL);
+	if (!db)
+		return -ENOMEM;
+
+	spi_set_drvdata(spi, db);
+
+	db->dev = dev;
+
+	db->panel_info = of_device_get_match_data(dev);
+	if (!db->panel_info)
+		return -EINVAL;
+
+	db->reg_vdd = devm_regulator_get(dev, "vdd");
+	if (IS_ERR(db->reg_vdd))
+		return dev_err_probe(dev, PTR_ERR(db->reg_vdd),
+				     "Failed to get vdd supply\n");
+
+	db->reg_elvdd = devm_regulator_get_optional(dev, "elvdd");
+	if (IS_ERR(db->reg_elvdd))
+		db->reg_elvdd = NULL;
+
+	db->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(db->reset)) {
+		ret = PTR_ERR(db->reset);
+		return dev_err_probe(dev, ret, "no RESET GPIO\n");
+	}
+
+	db->enable = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(db->enable)) {
+		ret = PTR_ERR(db->enable);
+		return dev_err_probe(dev, ret, "cannot get ENABLE GPIO\n");
+	}
+
+	ret = mipi_dbi_spi_init(spi, &db->dbi, NULL);
+	if (ret)
+		return dev_err_probe(dev, ret, "MIPI DBI init failed\n");
+
+	ret = drm_of_get_dsi_bus(dev, &dsi_host, &info);
+	if (ret)
+		return dev_err_probe(dev, ret, "Error attaching DSI bus\n");
+
+	db->dsi_dev = devm_mipi_dsi_device_register_full(dev, dsi_host, &info);
+	if (IS_ERR(db->dsi_dev)) {
+		dev_err(dev, "failed to register dsi device: %ld\n",
+			PTR_ERR(db->dsi_dev));
+		ret = PTR_ERR(db->dsi_dev);
+	}
+
+	db->dsi_dev->lanes = 2;
+	db->dsi_dev->format = MIPI_DSI_FMT_RGB888;
+	db->dsi_dev->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
+			  MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_NO_EOT_PACKET;
+
+	drm_panel_init(&db->panel, dev, db->panel_info->panel_funcs,
+		       DRM_MODE_CONNECTOR_DSI);
+
+	if (db->panel_info->backlight_register != NULL) {
+		ret = db->panel_info->backlight_register(db);
+		if (ret < 0)
+			return ret;
+	}
+
+	drm_panel_add(&db->panel);
+
+	ret = devm_mipi_dsi_attach(dev, db->dsi_dev);
+	if (ret < 0) {
+		dev_err(dev, "mipi_dsi_attach failed: %d\n", ret);
+		drm_panel_remove(&db->panel);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void d53e6ea8966_remove(struct spi_device *spi)
+{
+	struct d53e6ea8966 *db = spi_get_drvdata(spi);
+
+	drm_panel_remove(&db->panel);
+}
+
+static const struct drm_display_mode ams495qa01_modes[] = {
+	{ /* 60hz */
+		.clock = 33500,
+		.hdisplay = 960,
+		.hsync_start = 960 + 10,
+		.hsync_end = 960 + 10 + 2,
+		.htotal = 960 + 10 + 2 + 10,
+		.vdisplay = 544,
+		.vsync_start = 544 + 10,
+		.vsync_end = 544 + 10 + 2,
+		.vtotal = 544 + 10 + 2 + 10,
+		.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
+		.type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
+		},
+	{ /* 50hz */
+		.clock = 27800,
+		.hdisplay = 960,
+		.hsync_start = 960 + 10,
+		.hsync_end = 960 + 10 + 2,
+		.htotal = 960 + 10 + 2 + 10,
+		.vdisplay = 544,
+		.vsync_start = 544 + 10,
+		.vsync_end = 544 + 10 + 2,
+		.vtotal = 544 + 10 + 2 + 10,
+		.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
+		.type = DRM_MODE_TYPE_DRIVER,
+	},
+};
+
+static const struct d53e6ea8966_panel_info ams495qa01_info = {
+	.display_modes = ams495qa01_modes,
+	.num_modes = ARRAY_SIZE(ams495qa01_modes),
+	.width_mm = 117,
+	.height_mm = 74,
+	.bus_flags = DRM_BUS_FLAG_DE_LOW | DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE,
+	.panel_funcs = &ams495qa01_panel_funcs,
+	.backlight_register = ams495qa01_backlight_register,
+};
+
+static const struct of_device_id d53e6ea8966_match[] = {
+	{ .compatible = "samsung,ams495qa01", .data = &ams495qa01_info },
+	{},
+};
+MODULE_DEVICE_TABLE(of, d53e6ea8966_match);
+
+static const struct spi_device_id d53e6ea8966_ids[] = {
+	{ "ams495qa01", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(spi, d53e6ea8966_ids);
+
+static struct spi_driver d53e6ea8966_driver = {
+	.driver		= {
+		.name	= "d53e6ea8966-panel",
+		.of_match_table = d53e6ea8966_match,
+	},
+	.id_table	= d53e6ea8966_ids,
+	.probe		= d53e6ea8966_probe,
+	.remove		= d53e6ea8966_remove,
+};
+module_spi_driver(d53e6ea8966_driver);
+
+MODULE_AUTHOR("Chris Morgan <macromorgan@hotmail.com>");
+MODULE_DESCRIPTION("Magnachip d53e6ea8966 panel driver");
+MODULE_LICENSE("GPL");
-- 
2.34.1