diff mbox

[V5,10/12] drm/bridge: Add ps8622/ps8625 bridge driver

Message ID 1405629839-12086-11-git-send-email-ajaykumar.rs@samsung.com (mailing list archive)
State Superseded
Headers show

Commit Message

Ajay Kumar July 17, 2014, 8:43 p.m. UTC
From: Vincent Palatin <vpalatin@chromium.org>

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

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Rahul Sharma <rahul.sharma@samsung.com>
Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com>
---
 drivers/gpu/drm/bridge/Kconfig  |    8 +
 drivers/gpu/drm/bridge/Makefile |    1 +
 drivers/gpu/drm/bridge/ps8622.c |  476 +++++++++++++++++++++++++++++++++++++++
 include/drm/bridge/ps8622.h     |   41 ++++
 4 files changed, 526 insertions(+)
 create mode 100644 drivers/gpu/drm/bridge/ps8622.c
 create mode 100644 include/drm/bridge/ps8622.h
diff mbox

Patch

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..b5b7c31
--- /dev/null
+++ b/drivers/gpu/drm/bridge/ps8622.c
@@ -0,0 +1,476 @@ 
+/*
+ * 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;
+
+	struct gpio_desc *gpio_slp_n;
+	struct gpio_desc *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;
+
+	gpiod_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);
+
+	gpiod_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);
+
+	gpiod_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.
+	 */
+	gpiod_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);
+	gpiod_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");
+
+	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 = devm_gpiod_get(&client->dev, "sleep");
+	if (IS_ERR(ps_bridge->gpio_slp_n)) {
+		ret = PTR_ERR(ps_bridge->gpio_slp_n);
+		DRM_ERROR("cannot get gpio_slp_n %d\n", ret);
+		goto err_client;
+	} else {
+		ret = gpiod_direction_output(ps_bridge->gpio_slp_n, 1);
+		if (ret) {
+			DRM_ERROR("cannot configure gpio_slp_n\n");
+			goto err_client;
+		}
+	}
+
+	ps_bridge->gpio_rst_n = devm_gpiod_get(&client->dev, "reset");
+	if (IS_ERR(ps_bridge->gpio_rst_n)) {
+		ret = PTR_ERR(ps_bridge->gpio_rst_n);
+		DRM_ERROR("cannot get gpio_rst_n %d\n", ret);
+		goto err_client;
+	} else {
+		/*
+		 * Assert the reset pin high to avoid the bridge being
+		 * initialized prematurely
+		 */
+		ret = gpiod_direction_output(ps_bridge->gpio_rst_n, 1);
+		if (ret) {
+			DRM_ERROR("cannot configure gpio_slp_n\n");
+			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_INFO("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..c3914b6
--- /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;
+
+#if defined(CONFIG_DRM_PS8622) || defined(CONFIG_DRM_PS8622_MODULE)
+
+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