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Release 4.7 drivers/gpu/drm/bridge/parade-ps8622.c

/*
 * 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/gpio/consumer.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"
#include "drm_atomic_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); }

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static inline struct ps8622_bridge * connector_to_ps8622(struct drm_connector *connector) { return container_of(connector, struct ps8622_bridge, connector); }

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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); }

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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; }

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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; }

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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; }

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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; } }

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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); }

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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); }

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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); }

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static struct drm_encoder *ps8622_best_encoder(struct drm_connector *connector) { struct ps8622_bridge *ps8622; ps8622 = connector_to_ps8622(connector); return ps8622->bridge.encoder; }

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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; }

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static void ps8622_connector_destroy(struct drm_connector *connector) { drm_connector_cleanup(connector); }

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static const struct drm_connector_funcs ps8622_connector_funcs = { .dpms = drm_atomic_helper_connector_dpms, .fill_modes = drm_helper_probe_single_connector_modes, .detect = ps8622_detect, .destroy = ps8622_connector_destroy, .reset = drm_atomic_helper_connector_reset, .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, };
static 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; }

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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", GPIOD_OUT_HIGH); if (IS_ERR(ps8622->gpio_slp)) { ret = PTR_ERR(ps8622->gpio_slp); dev_err(dev, "cannot get gpio_slp %d\n", ret); return ret; } /* * Assert the reset pin high to avoid the bridge being * initialized prematurely */ ps8622->gpio_rst = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); if (IS_ERR(ps8622->gpio_rst)) { ret = PTR_ERR(ps8622->gpio_rst); dev_err(dev, "cannot get gpio_rst %d\n", ret); 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; }

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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; }

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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); static struct i2c_driver ps8622_driver = { .id_table = ps8622_i2c_table, .probe = ps8622_probe, .remove = ps8622_remove, .driver = { .name = "ps8622", .of_match_table = ps8622_devices, }, }; module_i2c_driver(ps8622_driver); MODULE_AUTHOR("Vincent Palatin <vpalatin@chromium.org>"); MODULE_DESCRIPTION("Parade ps8622/ps8625 eDP-LVDS converter driver"); MODULE_LICENSE("GPL v2");

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