[PATCH V9 12/14] drm/bridge: Add i2c based driver for ps8622/ps8625 bridge

Ajay Kumar ajaykumar.rs at samsung.com
Tue Jan 20 08:38:53 PST 2015


From: Vincent Palatin <vpalatin at chromium.org>

This patch adds drm_bridge driver for parade DisplayPort
to LVDS bridge chip.

Signed-off-by: Vincent Palatin <vpalatin at chromium.org>
Signed-off-by: Andrew Bresticker <abrestic at chromium.org>
Signed-off-by: Sean Paul <seanpaul at chromium.org>
Signed-off-by: Rahul Sharma <rahul.sharma at samsung.com>
Signed-off-by: Ajay Kumar <ajaykumar.rs at samsung.com>
Acked-by: Inki Dae <inki.dae at samsung.com>
Tested-by: Rahul Sharma <rahul.sharma at samsung.com>
Tested-by: Javier Martinez Canillas <javier.martinez at collabora.co.uk>
Tested-by: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
Tested-by: Sjoerd Simons <sjoerd.simons at collabora.co.uk>
---
 drivers/gpu/drm/bridge/Kconfig  |    9 +
 drivers/gpu/drm/bridge/Makefile |    1 +
 drivers/gpu/drm/bridge/ps8622.c |  684 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 694 insertions(+)
 create mode 100644 drivers/gpu/drm/bridge/ps8622.c

diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index 8b426e2..d06eda3 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -6,3 +6,12 @@ config DRM_PTN3460
 	select DRM_PANEL
 	---help---
 	  ptn3460 eDP-LVDS bridge chip driver.
+
+config DRM_PS8622
+	tristate "Parade eDP/LVDS bridge"
+	depends on OF && I2C
+	select DRM_PANEL
+	select BACKLIGHT_LCD_SUPPORT
+	select BACKLIGHT_CLASS_DEVICE
+	---help---
+	  parade eDP-LVDS bridge chip driver.
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index b4733e1..105da3e 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -1,3 +1,4 @@
 ccflags-y := -Iinclude/drm
 
+obj-$(CONFIG_DRM_PS8622) += ps8622.o
 obj-$(CONFIG_DRM_PTN3460) += ptn3460.o
diff --git a/drivers/gpu/drm/bridge/ps8622.c b/drivers/gpu/drm/bridge/ps8622.c
new file mode 100644
index 0000000..5474a39
--- /dev/null
+++ b/drivers/gpu/drm/bridge/ps8622.c
@@ -0,0 +1,684 @@
+/*
+ * Parade PS8622 eDP/LVDS bridge driver
+ *
+ * Copyright (C) 2014 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/fb.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_graph.h>
+#include <linux/pm.h>
+#include <linux/regulator/consumer.h>
+
+#include <drm/drm_panel.h>
+
+#include "drmP.h"
+#include "drm_crtc.h"
+#include "drm_crtc_helper.h"
+
+/* Brightness scale on the Parade chip */
+#define PS8622_MAX_BRIGHTNESS 0xff
+
+/* Timings taken from the version 1.7 datasheet for the PS8622/PS8625 */
+#define PS8622_POWER_RISE_T1_MIN_US 10
+#define PS8622_POWER_RISE_T1_MAX_US 10000
+#define PS8622_RST_HIGH_T2_MIN_US 3000
+#define PS8622_RST_HIGH_T2_MAX_US 30000
+#define PS8622_PWMO_END_T12_MS 200
+#define PS8622_POWER_FALL_T16_MAX_US 10000
+#define PS8622_POWER_OFF_T17_MS 500
+
+#if ((PS8622_RST_HIGH_T2_MIN_US + PS8622_POWER_RISE_T1_MAX_US) > \
+	(PS8622_RST_HIGH_T2_MAX_US + PS8622_POWER_RISE_T1_MIN_US))
+#error "T2.min + T1.max must be less than T2.max + T1.min"
+#endif
+
+struct ps8622_bridge {
+	struct drm_connector connector;
+	struct i2c_client *client;
+	struct drm_bridge bridge;
+	struct drm_panel *panel;
+	struct regulator *v12;
+	struct backlight_device *bl;
+
+	struct gpio_desc *gpio_slp;
+	struct gpio_desc *gpio_rst;
+
+	u32 max_lane_count;
+	u32 lane_count;
+
+	bool enabled;
+};
+
+static inline struct ps8622_bridge *
+		bridge_to_ps8622(struct drm_bridge *bridge)
+{
+	return container_of(bridge, struct ps8622_bridge, bridge);
+}
+
+static inline struct ps8622_bridge *
+		connector_to_ps8622(struct drm_connector *connector)
+{
+	return container_of(connector, struct ps8622_bridge, connector);
+}
+
+static int ps8622_set(struct i2c_client *client, u8 page, u8 reg, u8 val)
+{
+	int ret;
+	struct i2c_adapter *adap = client->adapter;
+	struct i2c_msg msg;
+	u8 data[] = {reg, val};
+
+	msg.addr = client->addr + page;
+	msg.flags = 0;
+	msg.len = sizeof(data);
+	msg.buf = data;
+
+	ret = i2c_transfer(adap, &msg, 1);
+	if (ret != 1)
+		pr_warn("PS8622 I2C write (0x%02x,0x%02x,0x%02x) failed: %d\n",
+			client->addr + page, reg, val, ret);
+	return !(ret == 1);
+}
+
+static int ps8622_send_config(struct ps8622_bridge *ps8622)
+{
+	struct i2c_client *cl = ps8622->client;
+	int err = 0;
+
+	/* HPD low */
+	err = ps8622_set(cl, 0x02, 0xa1, 0x01);
+	if (err)
+		goto error;
+
+	/* SW setting: [1:0] SW output 1.2V voltage is lower to 96% */
+	err = ps8622_set(cl, 0x04, 0x14, 0x01);
+	if (err)
+		goto error;
+
+	/* RCO SS setting: [5:4] = b01 0.5%, b10 1%, b11 1.5% */
+	err = ps8622_set(cl, 0x04, 0xe3, 0x20);
+	if (err)
+		goto error;
+
+	/* [7] RCO SS enable */
+	err = ps8622_set(cl, 0x04, 0xe2, 0x80);
+	if (err)
+		goto error;
+
+	/* RPHY Setting
+	 * [3:2] CDR tune wait cycle before measure for fine tune
+	 * b00: 1us b01: 0.5us b10:2us, b11: 4us
+	 */
+	err = ps8622_set(cl, 0x04, 0x8a, 0x0c);
+	if (err)
+		goto error;
+
+	/* [3] RFD always on */
+	err = ps8622_set(cl, 0x04, 0x89, 0x08);
+	if (err)
+		goto error;
+
+	/* CTN lock in/out: 20000ppm/80000ppm. Lock out 2 times. */
+	err = ps8622_set(cl, 0x04, 0x71, 0x2d);
+	if (err)
+		goto error;
+
+	/* 2.7G CDR settings: NOF=40LSB for HBR CDR  setting */
+	err = ps8622_set(cl, 0x04, 0x7d, 0x07);
+	if (err)
+		goto error;
+
+	/* [1:0] Fmin=+4bands */
+	err = ps8622_set(cl, 0x04, 0x7b, 0x00);
+	if (err)
+		goto error;
+
+	/* [7:5] DCO_FTRNG=+-40% */
+	err = ps8622_set(cl, 0x04, 0x7a, 0xfd);
+	if (err)
+		goto error;
+
+	/* 1.62G CDR settings: [5:2]NOF=64LSB [1:0]DCO scale is 2/5 */
+	err = ps8622_set(cl, 0x04, 0xc0, 0x12);
+	if (err)
+		goto error;
+
+	/* Gitune=-37% */
+	err = ps8622_set(cl, 0x04, 0xc1, 0x92);
+	if (err)
+		goto error;
+
+	/* Fbstep=100% */
+	err = ps8622_set(cl, 0x04, 0xc2, 0x1c);
+	if (err)
+		goto error;
+
+	/* [7] LOS signal disable */
+	err = ps8622_set(cl, 0x04, 0x32, 0x80);
+	if (err)
+		goto error;
+
+	/* RPIO Setting: [7:4] LVDS driver bias current : 75% (250mV swing) */
+	err = ps8622_set(cl, 0x04, 0x00, 0xb0);
+	if (err)
+		goto error;
+
+	/* [7:6] Right-bar GPIO output strength is 8mA */
+	err = ps8622_set(cl, 0x04, 0x15, 0x40);
+	if (err)
+		goto error;
+
+	/* EQ Training State Machine Setting, RCO calibration start */
+	err = ps8622_set(cl, 0x04, 0x54, 0x10);
+	if (err)
+		goto error;
+
+	/* Logic, needs more than 10 I2C command */
+	/* [4:0] MAX_LANE_COUNT set to max supported lanes */
+	err = ps8622_set(cl, 0x01, 0x02, 0x80 | ps8622->max_lane_count);
+	if (err)
+		goto error;
+
+	/* [4:0] LANE_COUNT_SET set to chosen lane count */
+	err = ps8622_set(cl, 0x01, 0x21, 0x80 | ps8622->lane_count);
+	if (err)
+		goto error;
+
+	err = ps8622_set(cl, 0x00, 0x52, 0x20);
+	if (err)
+		goto error;
+
+	/* HPD CP toggle enable */
+	err = ps8622_set(cl, 0x00, 0xf1, 0x03);
+	if (err)
+		goto error;
+
+	err = ps8622_set(cl, 0x00, 0x62, 0x41);
+	if (err)
+		goto error;
+
+	/* Counter number, add 1ms counter delay */
+	err = ps8622_set(cl, 0x00, 0xf6, 0x01);
+	if (err)
+		goto error;
+
+	/* [6]PWM function control by DPCD0040f[7], default is PWM block */
+	err = ps8622_set(cl, 0x00, 0x77, 0x06);
+	if (err)
+		goto error;
+
+	/* 04h Adjust VTotal toleranceto fix the 30Hz no display issue */
+	err = ps8622_set(cl, 0x00, 0x4c, 0x04);
+	if (err)
+		goto error;
+
+	/* DPCD00400='h00, Parade OUI ='h001cf8 */
+	err = ps8622_set(cl, 0x01, 0xc0, 0x00);
+	if (err)
+		goto error;
+
+	/* DPCD00401='h1c */
+	err = ps8622_set(cl, 0x01, 0xc1, 0x1c);
+	if (err)
+		goto error;
+
+	/* DPCD00402='hf8 */
+	err = ps8622_set(cl, 0x01, 0xc2, 0xf8);
+	if (err)
+		goto error;
+
+	/* DPCD403~408 = ASCII code, D2SLV5='h4432534c5635 */
+	err = ps8622_set(cl, 0x01, 0xc3, 0x44);
+	if (err)
+		goto error;
+
+	/* DPCD404 */
+	err = ps8622_set(cl, 0x01, 0xc4, 0x32);
+	if (err)
+		goto error;
+
+	/* DPCD405 */
+	err = ps8622_set(cl, 0x01, 0xc5, 0x53);
+	if (err)
+		goto error;
+
+	/* DPCD406 */
+	err = ps8622_set(cl, 0x01, 0xc6, 0x4c);
+	if (err)
+		goto error;
+
+	/* DPCD407 */
+	err = ps8622_set(cl, 0x01, 0xc7, 0x56);
+	if (err)
+		goto error;
+
+	/* DPCD408 */
+	err = ps8622_set(cl, 0x01, 0xc8, 0x35);
+	if (err)
+		goto error;
+
+	/* DPCD40A, Initial Code major revision '01' */
+	err = ps8622_set(cl, 0x01, 0xca, 0x01);
+	if (err)
+		goto error;
+
+	/* DPCD40B, Initial Code minor revision '05' */
+	err = ps8622_set(cl, 0x01, 0xcb, 0x05);
+	if (err)
+		goto error;
+
+
+	if (ps8622->bl) {
+		/* DPCD720, internal PWM */
+		err = ps8622_set(cl, 0x01, 0xa5, 0xa0);
+		if (err)
+			goto error;
+
+		/* FFh for 100% brightness, 0h for 0% brightness */
+		err = ps8622_set(cl, 0x01, 0xa7,
+				ps8622->bl->props.brightness);
+		if (err)
+			goto error;
+	} else {
+		/* DPCD720, external PWM */
+		err = ps8622_set(cl, 0x01, 0xa5, 0x80);
+		if (err)
+			goto error;
+	}
+
+	/* Set LVDS output as 6bit-VESA mapping, single LVDS channel */
+	err = ps8622_set(cl, 0x01, 0xcc, 0x13);
+	if (err)
+		goto error;
+
+	/* Enable SSC set by register */
+	err = ps8622_set(cl, 0x02, 0xb1, 0x20);
+	if (err)
+		goto error;
+
+	/* Set SSC enabled and +/-1% central spreading */
+	err = ps8622_set(cl, 0x04, 0x10, 0x16);
+	if (err)
+		goto error;
+
+	/* Logic end */
+	/* MPU Clock source: LC => RCO */
+	err = ps8622_set(cl, 0x04, 0x59, 0x60);
+	if (err)
+		goto error;
+
+	/* LC -> RCO */
+	err = ps8622_set(cl, 0x04, 0x54, 0x14);
+	if (err)
+		goto error;
+
+	/* HPD high */
+	err = ps8622_set(cl, 0x02, 0xa1, 0x91);
+
+error:
+	return err ? -EIO : 0;
+}
+
+static int ps8622_backlight_update(struct backlight_device *bl)
+{
+	struct ps8622_bridge *ps8622 = dev_get_drvdata(&bl->dev);
+	int ret, brightness = bl->props.brightness;
+
+	if (bl->props.power != FB_BLANK_UNBLANK ||
+	    bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
+		brightness = 0;
+
+	if (!ps8622->enabled)
+		return -EINVAL;
+
+	ret = ps8622_set(ps8622->client, 0x01, 0xa7, brightness);
+
+	return ret;
+}
+
+static const struct backlight_ops ps8622_backlight_ops = {
+	.update_status	= ps8622_backlight_update,
+};
+
+static void ps8622_pre_enable(struct drm_bridge *bridge)
+{
+	struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge);
+	int ret;
+
+	if (ps8622->enabled)
+		return;
+
+	gpiod_set_value(ps8622->gpio_rst, 0);
+
+	if (ps8622->v12) {
+		ret = regulator_enable(ps8622->v12);
+		if (ret)
+			DRM_ERROR("fails to enable ps8622->v12");
+	}
+
+	if (drm_panel_prepare(ps8622->panel)) {
+		DRM_ERROR("failed to prepare panel\n");
+		return;
+	}
+
+	gpiod_set_value(ps8622->gpio_slp, 1);
+
+	/*
+	 * T1 is the range of time that it takes for the power to rise after we
+	 * enable the lcd/ps8622 fet. T2 is the range of time in which the
+	 * data sheet specifies we should deassert the reset pin.
+	 *
+	 * If it takes T1.max for the power to rise, we need to wait atleast
+	 * T2.min before deasserting the reset pin. If it takes T1.min for the
+	 * power to rise, we need to wait at most T2.max before deasserting the
+	 * reset pin.
+	 */
+	usleep_range(PS8622_RST_HIGH_T2_MIN_US + PS8622_POWER_RISE_T1_MAX_US,
+		     PS8622_RST_HIGH_T2_MAX_US + PS8622_POWER_RISE_T1_MIN_US);
+
+	gpiod_set_value(ps8622->gpio_rst, 1);
+
+	/* wait 20ms after RST high */
+	usleep_range(20000, 30000);
+
+	ret = ps8622_send_config(ps8622);
+	if (ret) {
+		DRM_ERROR("Failed to send config to bridge (%d)\n", ret);
+		return;
+	}
+
+	ps8622->enabled = true;
+}
+
+static void ps8622_enable(struct drm_bridge *bridge)
+{
+	struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge);
+
+	if (drm_panel_enable(ps8622->panel)) {
+		DRM_ERROR("failed to enable panel\n");
+		return;
+	}
+}
+
+static void ps8622_disable(struct drm_bridge *bridge)
+{
+	struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge);
+
+	if (drm_panel_disable(ps8622->panel)) {
+		DRM_ERROR("failed to disable panel\n");
+		return;
+	}
+	msleep(PS8622_PWMO_END_T12_MS);
+}
+
+static void ps8622_post_disable(struct drm_bridge *bridge)
+{
+	struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge);
+
+	if (!ps8622->enabled)
+		return;
+
+	ps8622->enabled = false;
+
+	/*
+	 * This doesn't matter if the regulators are turned off, but something
+	 * else might keep them on. In that case, we want to assert the slp gpio
+	 * to lower power.
+	 */
+	gpiod_set_value(ps8622->gpio_slp, 0);
+
+	if (drm_panel_unprepare(ps8622->panel)) {
+		DRM_ERROR("failed to unprepare panel\n");
+		return;
+	}
+
+	if (ps8622->v12)
+		regulator_disable(ps8622->v12);
+
+	/*
+	 * Sleep for at least the amount of time that it takes the power rail to
+	 * fall to prevent asserting the rst gpio from doing anything.
+	 */
+	usleep_range(PS8622_POWER_FALL_T16_MAX_US,
+		     2 * PS8622_POWER_FALL_T16_MAX_US);
+	gpiod_set_value(ps8622->gpio_rst, 0);
+
+	msleep(PS8622_POWER_OFF_T17_MS);
+}
+
+static int ps8622_get_modes(struct drm_connector *connector)
+{
+	struct ps8622_bridge *ps8622;
+
+	ps8622 = connector_to_ps8622(connector);
+
+	return drm_panel_get_modes(ps8622->panel);
+}
+
+static struct drm_encoder *ps8622_best_encoder(struct drm_connector *connector)
+{
+	struct ps8622_bridge *ps8622;
+
+	ps8622 = connector_to_ps8622(connector);
+
+	return ps8622->bridge.encoder;
+}
+
+static const struct drm_connector_helper_funcs ps8622_connector_helper_funcs = {
+	.get_modes = ps8622_get_modes,
+	.best_encoder = ps8622_best_encoder,
+};
+
+static enum drm_connector_status ps8622_detect(struct drm_connector *connector,
+								bool force)
+{
+	return connector_status_connected;
+}
+
+static void ps8622_connector_destroy(struct drm_connector *connector)
+{
+	drm_connector_cleanup(connector);
+}
+
+static const struct drm_connector_funcs ps8622_connector_funcs = {
+	.dpms = drm_helper_connector_dpms,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.detect = ps8622_detect,
+	.destroy = ps8622_connector_destroy,
+};
+
+int ps8622_attach(struct drm_bridge *bridge)
+{
+	struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge);
+	int ret;
+
+	if (!bridge->encoder) {
+		DRM_ERROR("Parent encoder object not found");
+		return -ENODEV;
+	}
+
+	ps8622->connector.polled = DRM_CONNECTOR_POLL_HPD;
+	ret = drm_connector_init(bridge->dev, &ps8622->connector,
+			&ps8622_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
+	if (ret) {
+		DRM_ERROR("Failed to initialize connector with drm\n");
+		return ret;
+	}
+	drm_connector_helper_add(&ps8622->connector,
+					&ps8622_connector_helper_funcs);
+	drm_connector_register(&ps8622->connector);
+	drm_mode_connector_attach_encoder(&ps8622->connector,
+							bridge->encoder);
+
+	if (ps8622->panel)
+		drm_panel_attach(ps8622->panel, &ps8622->connector);
+
+	drm_helper_hpd_irq_event(ps8622->connector.dev);
+
+	return ret;
+}
+
+static const struct drm_bridge_funcs ps8622_bridge_funcs = {
+	.pre_enable = ps8622_pre_enable,
+	.enable = ps8622_enable,
+	.disable = ps8622_disable,
+	.post_disable = ps8622_post_disable,
+	.attach = ps8622_attach,
+};
+
+static const struct of_device_id ps8622_devices[] = {
+	{.compatible = "parade,ps8622",},
+	{.compatible = "parade,ps8625",},
+	{}
+};
+MODULE_DEVICE_TABLE(of, ps8622_devices);
+
+static int ps8622_probe(struct i2c_client *client,
+					const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct device_node *endpoint, *panel_node;
+	struct ps8622_bridge *ps8622;
+	int ret;
+
+	ps8622 = devm_kzalloc(dev, sizeof(*ps8622), GFP_KERNEL);
+	if (!ps8622)
+		return -ENOMEM;
+
+	endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
+	if (endpoint) {
+		panel_node = of_graph_get_remote_port_parent(endpoint);
+		if (panel_node) {
+			ps8622->panel = of_drm_find_panel(panel_node);
+			of_node_put(panel_node);
+			if (!ps8622->panel)
+				return -EPROBE_DEFER;
+		}
+	}
+
+	ps8622->client = client;
+
+	ps8622->v12 = devm_regulator_get(dev, "vdd12");
+	if (IS_ERR(ps8622->v12)) {
+		dev_info(dev, "no 1.2v regulator found for PS8622\n");
+		ps8622->v12 = NULL;
+	}
+
+	ps8622->gpio_slp = devm_gpiod_get(dev, "sleep");
+	if (IS_ERR(ps8622->gpio_slp)) {
+		ret = PTR_ERR(ps8622->gpio_slp);
+		dev_err(dev, "cannot get gpio_slp %d\n", ret);
+		return ret;
+	}
+	ret = gpiod_direction_output(ps8622->gpio_slp, 1);
+	if (ret) {
+		dev_err(dev, "cannot configure gpio_slp\n");
+		return ret;
+	}
+
+	ps8622->gpio_rst = devm_gpiod_get(dev, "reset");
+	if (IS_ERR(ps8622->gpio_rst)) {
+		ret = PTR_ERR(ps8622->gpio_rst);
+		dev_err(dev, "cannot get gpio_rst %d\n", ret);
+		return ret;
+	}
+	/*
+	 * Assert the reset pin high to avoid the bridge being
+	 * initialized prematurely
+	 */
+	ret = gpiod_direction_output(ps8622->gpio_rst, 1);
+	if (ret) {
+		dev_err(dev, "cannot configure gpio_rst\n");
+		return ret;
+	}
+
+	ps8622->max_lane_count = id->driver_data;
+
+	if (of_property_read_u32(dev->of_node, "lane-count",
+						&ps8622->lane_count)) {
+		ps8622->lane_count = ps8622->max_lane_count;
+	} else if (ps8622->lane_count > ps8622->max_lane_count) {
+		dev_info(dev, "lane-count property is too high,"
+						"using max_lane_count\n");
+		ps8622->lane_count = ps8622->max_lane_count;
+	}
+
+	if (!of_find_property(dev->of_node, "use-external-pwm", NULL)) {
+		ps8622->bl = backlight_device_register("ps8622-backlight",
+				dev, ps8622, &ps8622_backlight_ops,
+				NULL);
+		if (IS_ERR(ps8622->bl)) {
+			DRM_ERROR("failed to register backlight\n");
+			ret = PTR_ERR(ps8622->bl);
+			ps8622->bl = NULL;
+			return ret;
+		}
+		ps8622->bl->props.max_brightness = PS8622_MAX_BRIGHTNESS;
+		ps8622->bl->props.brightness = PS8622_MAX_BRIGHTNESS;
+	}
+
+	ps8622->bridge.funcs = &ps8622_bridge_funcs;
+	ps8622->bridge.of_node = dev->of_node;
+	ret = drm_bridge_add(&ps8622->bridge);
+	if (ret) {
+		DRM_ERROR("Failed to add bridge\n");
+		return ret;
+	}
+
+	i2c_set_clientdata(client, ps8622);
+
+	return 0;
+}
+
+static int ps8622_remove(struct i2c_client *client)
+{
+	struct ps8622_bridge *ps8622 = i2c_get_clientdata(client);
+
+	if (ps8622->bl)
+		backlight_device_unregister(ps8622->bl);
+
+	drm_bridge_remove(&ps8622->bridge);
+
+	return 0;
+}
+
+static const struct i2c_device_id ps8622_i2c_table[] = {
+	/* Device type, max_lane_count */
+	{"ps8622", 1},
+	{"ps8625", 2},
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, ps8622_i2c_table);
+
+struct i2c_driver ps8622_driver = {
+	.id_table	= ps8622_i2c_table,
+	.probe		= ps8622_probe,
+	.remove		= ps8622_remove,
+	.driver		= {
+		.name	= "ps8622",
+		.owner	= THIS_MODULE,
+		.of_match_table = ps8622_devices,
+	},
+};
+module_i2c_driver(ps8622_driver);
+
+MODULE_AUTHOR("Vincent Palatin <vpalatin at chromium.org>");
+MODULE_DESCRIPTION("Parade ps8622/ps8625 eDP-LVDS converter driver");
+MODULE_LICENSE("GPL v2");
-- 
1.7.9.5




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