On Fri, Jun 6, 2014 at 12:46 AM, Ajay kumar <ajaynumb at gmail.com> wrote:
> + Device tree list
>
>
> On Fri, Jun 6, 2014 at 12:40 AM, Ajay Kumar <ajaykumar.rs at samsung.com>
> wrote:
>> 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>
>> ---
>> .../devicetree/bindings/drm/bridge/ps8622.txt | 21 +
>> drivers/gpu/drm/bridge/Kconfig | 8 +
>> drivers/gpu/drm/bridge/Makefile | 1 +
>> drivers/gpu/drm/bridge/ps8622.c | 475
>> ++++++++++++++++++++
>> include/drm/bridge/ps8622.h | 41 ++
>> 5 files changed, 546 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/drm/bridge/ps8622.txt
>> create mode 100644 drivers/gpu/drm/bridge/ps8622.c
>> create mode 100644 include/drm/bridge/ps8622.h
>>
>> diff --git a/Documentation/devicetree/bindings/drm/bridge/ps8622.txt
>> b/Documentation/devicetree/bindings/drm/bridge/ps8622.txt
>> new file mode 100644
>> index 0000000..1afbd9c
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/drm/bridge/ps8622.txt
>> @@ -0,0 +1,21 @@
>> +ps8622-bridge bindings
>> +
>> +Required properties:
>> + - compatible: "parade,ps8622"
>> + - reg: first i2c address of the bridge
>> + - sleep-gpio: OF device-tree gpio specification
>> + - reset-gpio: OF device-tree gpio specification
>> +
>> +Optional properties:
>> + - lane-count: number of DP lanes to use
>> + - use-external-pwm: backlight will be controlled by an external PWM
>> +
>> +Example:
>> + ps8622-bridge at 48 {
>> + compatible = "parade,ps8622";
>> + reg = <0x48>;
>> + sleep-gpio = <&gpc3 6 1 0 0>;
>> + reset-gpio = <&gpc3 1 1 0 0>;
>> + display-timings = <&lcd_display_timings>;
>> + lane-count = <1>
>> + };
>> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
>> index e3fb487..7b843c8 100644
>> --- a/drivers/gpu/drm/bridge/Kconfig
>> +++ b/drivers/gpu/drm/bridge/Kconfig
>> @@ -10,3 +10,11 @@ config DRM_PANEL_BINDER
>> select DRM_KMS_HELPER
>> select DRM_PANEL
>> ---help---
>> +
>> +config DRM_PS8622
>> + tristate "Parade eDP/LVDS bridge"
>> + depends on DRM
>> + select DRM_KMS_HELPER
>> + select BACKLIGHT_LCD_SUPPORT
>> + select BACKLIGHT_CLASS_DEVICE
>> + ---help---
>> diff --git a/drivers/gpu/drm/bridge/Makefile
>> b/drivers/gpu/drm/bridge/Makefile
>> index ba8b5b8..b494d4b 100644
>> --- a/drivers/gpu/drm/bridge/Makefile
>> +++ b/drivers/gpu/drm/bridge/Makefile
>> @@ -2,3 +2,4 @@ ccflags-y := -Iinclude/drm
>>
>> obj-$(CONFIG_DRM_PTN3460) += ptn3460.o
>> obj-$(CONFIG_DRM_PANEL_BINDER) += panel_binder.o
>> +obj-$(CONFIG_DRM_PS8622) += ps8622.o
>> diff --git a/drivers/gpu/drm/bridge/ps8622.c
>> b/drivers/gpu/drm/bridge/ps8622.c
>> new file mode 100644
>> index 0000000..387d332
>> --- /dev/null
>> +++ b/drivers/gpu/drm/bridge/ps8622.c
>> @@ -0,0 +1,475 @@
>> +/*
>> + * 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/module.h>
>> +#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/of.h>
>> +#include <linux/of_gpio.h>
>> +#include <linux/pm.h>
>> +#include <linux/regulator/consumer.h>
>> +
>> +#include "drmP.h"
>> +#include "drm_crtc.h"
>> +#include "drm_crtc_helper.h"
>> +
>> +struct ps8622_bridge {
>> + struct drm_bridge *bridge;
>> + struct drm_encoder *encoder;
>> + struct i2c_client *client;
>> + struct regulator *v12;
>> + struct backlight_device *bl;
>> + struct mutex enable_mutex;
>> +
>> + int gpio_slp_n;
>> + int gpio_rst_n;
>> +
>> + u8 max_lane_count;
>> + u8 lane_count;
>> +
>> + bool enabled;
>> +};
>> +
>> +struct ps8622_device_data {
>> + u8 max_lane_count;
>> +};
>> +
>> +static const struct ps8622_device_data ps8622_data = {
>> + .max_lane_count = 1,
>> +};
>> +
>> +static const struct ps8622_device_data ps8625_data = {
>> + .max_lane_count = 2,
>> +};
>> +
>> +/* 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
>> +
>> +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 *ps_bridge)
>> +{
>> + struct i2c_client *cl = ps_bridge->client;
>> + int err = 0;
>> +
>> + /* wait 20ms after power ON */
>> + usleep_range(20000, 30000);
>> +
>> + err |= ps8622_set(cl, 0x02, 0xa1, 0x01); /* HPD low */
>> + /* SW setting */
>> + err |= ps8622_set(cl, 0x04, 0x14, 0x01); /* [1:0] SW output 1.2V
>> voltage
>> + * is lower to 96% */
>> + /* RCO SS setting */
>> + err |= ps8622_set(cl, 0x04, 0xe3, 0x20); /* [5:4] = b01 0.5%, b10 1%,
>> + * b11 1.5% */
>> + err |= ps8622_set(cl, 0x04, 0xe2, 0x80); /* [7] RCO SS enable */
>> + /* RPHY Setting */
>> + err |= ps8622_set(cl, 0x04, 0x8a, 0x0c); /* [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, 0x89, 0x08); /* [3] RFD always on */
>> + err |= ps8622_set(cl, 0x04, 0x71, 0x2d); /* CTN lock in/out:
>> + * 20000ppm/80000ppm.
>> + * Lock out 2 times. */
>> + /* 2.7G CDR settings */
>> + err |= ps8622_set(cl, 0x04, 0x7d, 0x07); /* NOF=40LSB for HBR CDR
>> + * setting */
>> + err |= ps8622_set(cl, 0x04, 0x7b, 0x00); /* [1:0] Fmin=+4bands */
>> + err |= ps8622_set(cl, 0x04, 0x7a, 0xfd); /* [7:5] DCO_FTRNG=+-40% */
>> + /* 1.62G CDR settings */
>> + err |= ps8622_set(cl, 0x04, 0xc0, 0x12); /* [5:2]NOF=64LSB [1:0]DCO
>> + * scale is 2/5 */
>> + err |= ps8622_set(cl, 0x04, 0xc1, 0x92); /* Gitune=-37% */
>> + err |= ps8622_set(cl, 0x04, 0xc2, 0x1c); /* Fbstep=100% */
>> + err |= ps8622_set(cl, 0x04, 0x32, 0x80); /* [7] LOS signal disable */
>> + /* RPIO Setting */
>> + err |= ps8622_set(cl, 0x04, 0x00, 0xb0); /* [7:4] LVDS driver bias
>> + * current : 75% (250mV
>> swing)
>> + * */
>> + err |= ps8622_set(cl, 0x04, 0x15, 0x40); /* [7:6] Right-bar GPIO
>> output
>> + * strength is 8mA */
>> + /* EQ Training State Machine Setting */
>> + err |= ps8622_set(cl, 0x04, 0x54, 0x10); /* RCO calibration start */
>> + /* Logic, needs more than 10 I2C command */
>> + err |= ps8622_set(cl, 0x01, 0x02, 0x80 | ps_bridge->max_lane_count);
>> + /* [4:0] MAX_LANE_COUNT set
>> to
>> + * max supported lanes */
>> + err |= ps8622_set(cl, 0x01, 0x21, 0x80 | ps_bridge->lane_count);
>> + /* [4:0] LANE_COUNT_SET set
>> to
>> + * chosen lane count */
>> + err |= ps8622_set(cl, 0x00, 0x52, 0x20);
>> + err |= ps8622_set(cl, 0x00, 0xf1, 0x03); /* HPD CP toggle enable */
>> + err |= ps8622_set(cl, 0x00, 0x62, 0x41);
>> + err |= ps8622_set(cl, 0x00, 0xf6, 0x01); /* Counter number, add 1ms
>> + * counter delay */
>> + err |= ps8622_set(cl, 0x00, 0x77, 0x06); /* [6]PWM function control
>> by
>> + * DPCD0040f[7], default is
>> PWM
>> + * block always works. */
>> + err |= ps8622_set(cl, 0x00, 0x4c, 0x04); /* 04h Adjust VTotal
>> tolerance
>> + * to fix the 30Hz no
>> display
>> + * issue */
>> + err |= ps8622_set(cl, 0x01, 0xc0, 0x00); /* DPCD00400='h00, Parade
>> OUI =
>> + * 'h001cf8 */
>> + err |= ps8622_set(cl, 0x01, 0xc1, 0x1c); /* DPCD00401='h1c */
>> + err |= ps8622_set(cl, 0x01, 0xc2, 0xf8); /* DPCD00402='hf8 */
>> + err |= ps8622_set(cl, 0x01, 0xc3, 0x44); /* DPCD403~408 = ASCII code
>> + * D2SLV5='h4432534c5635 */
>> + err |= ps8622_set(cl, 0x01, 0xc4, 0x32); /* DPCD404 */
>> + err |= ps8622_set(cl, 0x01, 0xc5, 0x53); /* DPCD405 */
>> + err |= ps8622_set(cl, 0x01, 0xc6, 0x4c); /* DPCD406 */
>> + err |= ps8622_set(cl, 0x01, 0xc7, 0x56); /* DPCD407 */
>> + err |= ps8622_set(cl, 0x01, 0xc8, 0x35); /* DPCD408 */
>> + err |= ps8622_set(cl, 0x01, 0xca, 0x01); /* DPCD40A, Initial Code
>> major
>> + * revision '01' */
>> + err |= ps8622_set(cl, 0x01, 0xcb, 0x05); /* DPCD40B, Initial Code
>> minor
>> + * revision '05' */
>> + if (ps_bridge->bl) {
>> + err |= ps8622_set(cl, 0x01, 0xa5, 0xa0);
>> + /* DPCD720, internal PWM */
>> + err |= ps8622_set(cl, 0x01, 0xa7,
>> + ps_bridge->bl->props.brightness);
>> + /* FFh for 100% brightness,
>> + * 0h for 0% brightness */
>> + } else {
>> + err |= ps8622_set(cl, 0x01, 0xa5, 0x80);
>> + /* DPCD720, external PWM */
>> + }
>> + err |= ps8622_set(cl, 0x01, 0xcc, 0x13); /* Set LVDS output as
>> 6bit-VESA
>> + * mapping, single LVDS
>> channel
>> + * */
>> + err |= ps8622_set(cl, 0x02, 0xb1, 0x20); /* Enable SSC set by
>> register
>> + * */
>> + err |= ps8622_set(cl, 0x04, 0x10, 0x16); /* Set SSC enabled and +/-1%
>> + * central spreading */
>> + /* Logic end */
>> + err |= ps8622_set(cl, 0x04, 0x59, 0x60); /* MPU Clock source: LC =>
>> RCO
>> + * */
>> + err |= ps8622_set(cl, 0x04, 0x54, 0x14); /* LC -> RCO */
>> + err |= ps8622_set(cl, 0x02, 0xa1, 0x91); /* HPD high */
>> +
>> + return err ? -EIO : 0;
>> +}
>> +
>> +static int ps8622_backlight_update(struct backlight_device *bl)
>> +{
>> + struct ps8622_bridge *ps_bridge = 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;
>> +
>> + mutex_lock(&ps_bridge->enable_mutex);
>> +
>> + if (!ps_bridge->enabled) {
>> + ret = -EINVAL;
>> + goto out;
>> + }
>> +
>> + ret = ps8622_set(ps_bridge->client, 0x01, 0xa7, brightness);
>> +
>> +out:
>> + mutex_unlock(&ps_bridge->enable_mutex);
>> + return ret;
>> +}
>> +
>> +static int ps8622_backlight_get(struct backlight_device *bl)
>> +{
>> + return bl->props.brightness;
>> +}
>> +
>> +static const struct backlight_ops ps8622_backlight_ops = {
>> + .update_status = ps8622_backlight_update,
>> + .get_brightness = ps8622_backlight_get,
>> +};
>> +
>> +static void ps8622_pre_enable(struct drm_bridge *bridge)
>> +{
>> + struct ps8622_bridge *ps_bridge = bridge->driver_private;
>> + int ret;
>> +
>> + mutex_lock(&ps_bridge->enable_mutex);
>> + if (ps_bridge->enabled)
>> + goto out;
>> +
>> + if (gpio_is_valid(ps_bridge->gpio_rst_n))
>> + gpio_set_value(ps_bridge->gpio_rst_n, 0);
>> +
>> + if (ps_bridge->v12) {
>> + ret = regulator_enable(ps_bridge->v12);
>> + if (ret)
>> + DRM_ERROR("fails to enable ps_bridge->v12");
>> + }
>> +
>> + drm_next_bridge_pre_enable(bridge);
>> +
>> + if (gpio_is_valid(ps_bridge->gpio_slp_n))
>> + gpio_set_value(ps_bridge->gpio_slp_n, 1);
>> +
>> + /*
>> + * T1 is the range of time that it takes for the power to rise after
>> we
>> + * enable the lcd 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);
>> +
>> + if (gpio_is_valid(ps_bridge->gpio_rst_n))
>> + gpio_set_value(ps_bridge->gpio_rst_n, 1);
>> +
>> + ret = ps8622_send_config(ps_bridge);
>> + if (ret)
>> + DRM_ERROR("Failed to send config to bridge (%d)\n", ret);
>> +
>> + ps_bridge->enabled = true;
>> +
>> +out:
>> + mutex_unlock(&ps_bridge->enable_mutex);
>> +}
>> +
>> +static void ps8622_enable(struct drm_bridge *bridge)
>> +{
>> + struct ps8622_bridge *ps_bridge = bridge->driver_private;
>> +
>> + mutex_lock(&ps_bridge->enable_mutex);
>> + drm_next_bridge_enable(bridge);
>> + mutex_unlock(&ps_bridge->enable_mutex);
>> +}
>> +
>> +static void ps8622_disable(struct drm_bridge *bridge)
>> +{
>> + struct ps8622_bridge *ps_bridge = bridge->driver_private;
>> +
>> + mutex_lock(&ps_bridge->enable_mutex);
>> +
>> + if (!ps_bridge->enabled)
>> + goto out;
>> +
>> + ps_bridge->enabled = false;
>> +
>> + drm_next_bridge_disable(bridge);
>> + msleep(PS8622_PWMO_END_T12_MS);
>> +
>> + /*
>> + * 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.
>> + */
>> + if (gpio_is_valid(ps_bridge->gpio_slp_n))
>> + gpio_set_value(ps_bridge->gpio_slp_n, 0);
>> +
>> + if (ps_bridge->v12)
>> + regulator_disable(ps_bridge->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);
>> + if (gpio_is_valid(ps_bridge->gpio_rst_n))
>> + gpio_set_value(ps_bridge->gpio_rst_n, 0);
>> +
>> + msleep(PS8622_POWER_OFF_T17_MS);
>> +
>> +out:
>> + mutex_unlock(&ps_bridge->enable_mutex);
>> +}
>> +
>> +static void ps8622_post_disable(struct drm_bridge *bridge)
>> +{
>> + drm_next_bridge_post_disable(bridge);
>> +}
>> +
>> +static void ps8622_destroy(struct drm_bridge *bridge)
>> +{
>> + struct ps8622_bridge *ps_bridge = bridge->driver_private;
>> +
>> + drm_bridge_cleanup(bridge);
>> + if (ps_bridge->bl)
>> + backlight_device_unregister(ps_bridge->bl);
>> +
>> + put_device(&ps_bridge->client->dev);
>> +}
>> +
>> +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,
>> + .destroy = ps8622_destroy,
>> +};
>> +
>> +static const struct of_device_id ps8622_devices[] = {
>> + {
>> + .compatible = "parade,ps8622",
>> + .data = &ps8622_data,
>> + }, {
>> + .compatible = "parade,ps8625",
>> + .data = &ps8625_data,
>> + }, {
>> + /* end node */
>> + }
>> +};
>> +
>> +struct drm_bridge *ps8622_init(struct drm_device *dev,
>> + struct drm_encoder *encoder,
>> + struct i2c_client *client,
>> + struct device_node *node)
>> +{
>> + int ret;
>> + const struct of_device_id *match;
>> + const struct ps8622_device_data *device_data;
>> + struct drm_bridge *bridge;
>> + struct ps8622_bridge *ps_bridge;
>> +
>> + node = of_find_matching_node_and_match(NULL, ps8622_devices, &match);
>> + if (!node)
>> + return NULL;
>> +
>> + bridge = devm_kzalloc(dev->dev, sizeof(*bridge), GFP_KERNEL);
>> + if (!bridge) {
>> + DRM_ERROR("Failed to allocate drm bridge\n");
>> + return NULL;
>> + }
>> +
>> + ps_bridge = devm_kzalloc(dev->dev, sizeof(*ps_bridge), GFP_KERNEL);
>> + if (!ps_bridge) {
>> + DRM_ERROR("could not allocate ps bridge\n");
>> + return NULL;
>> + }
>> +
>> + mutex_init(&ps_bridge->enable_mutex);
>> +
>> + device_data = match->data;
>> + ps_bridge->client = client;
>> + ps_bridge->encoder = encoder;
>> + ps_bridge->bridge = bridge;
>> + ps_bridge->v12 = devm_regulator_get(&client->dev, "vdd_bridge");
>> + if (IS_ERR(ps_bridge->v12)) {
>> + DRM_INFO("no 1.2v regulator found for PS8622\n");
>> + ps_bridge->v12 = NULL;
>> + }
>> +
>> + ps_bridge->gpio_slp_n = of_get_named_gpio(node, "sleep-gpio", 0);
>> + if (gpio_is_valid(ps_bridge->gpio_slp_n)) {
>> + ret = devm_gpio_request_one(&client->dev,
>> ps_bridge->gpio_slp_n,
>> + GPIOF_OUT_INIT_HIGH,
>> + "PS8622_SLP_N");
>> + if (ret)
>> + goto err_client;
>> + }
>> +
>> + ps_bridge->gpio_rst_n = of_get_named_gpio(node, "reset-gpio", 0);
>> + if (gpio_is_valid(ps_bridge->gpio_rst_n)) {
>> + /*
>> + * Assert the reset pin high to avoid the bridge being
>> + * initialized prematurely
>> + */
>> + ret = devm_gpio_request_one(&client->dev,
>> ps_bridge->gpio_rst_n,
>> + GPIOF_OUT_INIT_HIGH,
>> + "PS8622_RST_N");
>> + if (ret)
>> + goto err_client;
>> + }
>> +
>> + ps_bridge->max_lane_count = device_data->max_lane_count;
>> +
>> + if (of_property_read_u8(node, "lane-count", &ps_bridge->lane_count))
>> + ps_bridge->lane_count = ps_bridge->max_lane_count;
>> + else if (ps_bridge->lane_count > ps_bridge->max_lane_count) {
>> + DRM_ERROR("lane-count property is too high for DP bridge\n");
>> + ps_bridge->lane_count = ps_bridge->max_lane_count;
>> + }
>> +
>> + if (!of_find_property(node, "use-external-pwm", NULL)) {
>> + ps_bridge->bl = backlight_device_register("ps8622-backlight",
>> + dev->dev, ps_bridge, &ps8622_backlight_ops,
>> + NULL);
>> + if (IS_ERR(ps_bridge->bl)) {
>> + DRM_ERROR("failed to register backlight\n");
>> + ret = PTR_ERR(ps_bridge->bl);
>> + ps_bridge->bl = NULL;
>> + goto err_client;
>> + }
>> + ps_bridge->bl->props.max_brightness = PS8622_MAX_BRIGHTNESS;
>> + ps_bridge->bl->props.brightness = PS8622_MAX_BRIGHTNESS;
>> + }
>> +
>> + ret = drm_bridge_init(dev, ps_bridge->bridge, &ps8622_bridge_funcs);
>> + if (ret) {
>> + DRM_ERROR("Failed to initialize bridge with drm\n");
>> + goto err_backlight;
>> + }
>> +
>> + ps_bridge->bridge->driver_private = ps_bridge;
>> + ps_bridge->enabled = false;
>> +
>> + if (!encoder->bridge)
>> + /* First entry in the bridge chain */
>> + encoder->bridge = bridge;
>> +
>> + return bridge;
>> +
>> +err_backlight:
>> + if (ps_bridge->bl)
>> + backlight_device_unregister(ps_bridge->bl);
>> +err_client:
>> + put_device(&client->dev);
>> + DRM_ERROR("device probe failed : %d\n", ret);
>> + return NULL;
>> +}
>> +EXPORT_SYMBOL(ps8622_init);
>> diff --git a/include/drm/bridge/ps8622.h b/include/drm/bridge/ps8622.h
>> new file mode 100644
>> index 0000000..22f37b6
>> --- /dev/null
>> +++ b/include/drm/bridge/ps8622.h
>> @@ -0,0 +1,41 @@
>> +/*
>> + * 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.
>> + */
>> +
>> +#ifndef _DRM_BRIDGE_PS8622_H_
>> +#define _DRM_BRIDGE_PS8622_H_
>> +
>> +struct drm_device;
>> +struct drm_encoder;
>> +struct i2c_client;
>> +struct device_node;
>> +
>> +#ifdef CONFIG_DRM_PS8622
>> +
>> +struct drm_bridge *ps8622_init(struct drm_device *dev,
>> + struct drm_encoder *encoder,
>> + struct i2c_client *client,
>> + struct device_node *node);
>> +
>> +#else
>> +
>> +static inline struct drm_bridge *ps8622_init(struct drm_device *dev,
>> + struct drm_encoder *encoder,
>> + struct i2c_client *client,
>> + struct device_node *node)
>> +{
>> + return -ENODEV;
>> +}
>> +
>> +#endif
>> +
>> +#endif
>> --
>> 1.7.9.5
>>