blob: ae5097160f7bae0a4d21204aa5a61c534f7efa74 [file] [log] [blame]
/*
* Copyright (c) 2014 The Chromium OS Authors. All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* This file is a driver for Parade dP<->LVDS bridges. The original submission
* is for the ps8625 chip.
*/
#include <config.h>
#include <common.h>
#include <i2c.h>
#include <fdtdec.h>
#include <asm/gpio.h>
/*
* Initialization of the chip is a process of writing certaing values into
* certain registers over i2c bus. The chip in fact responds to a range of
* addresses on the i2c bus, so for each written value three parameters are
* required: i2c address, register address and the actual value.
*
* The base address is derived from the device tree, only address offset is
* stored in the table below.
*/
/**
* struct reg_data() - data for a parade register write
*
* @addr_off offset from the i2c base address for parade
* @reg_addr register address to write
* @value value to be written
*/
struct reg_data {
uint8_t addr_off;
uint8_t reg;
uint8_t value;
} _packed;
#define END_OF_TABLE 0xff /* Ficticious offset */
static const struct reg_data parade_values[] = {
{0x02, 0xa1, 0x01}, /* HPD low */
/*
* SW setting
* [1:0] SW output 1.2V voltage is lower to 96%
*/
{0x04, 0x14, 0x01},
/*
* RCO SS setting
* [5:4] = b01 0.5%, b10 1%, b11 1.5%
*/
{0x04, 0xe3, 0x20},
{0x04, 0xe2, 0x80}, /* [7] RCO SS enable */
/*
* RPHY Setting
* [3:2] CDR tune wait cycle before
* measure for fine tune b00: 1us,
* 01: 0.5us, 10:2us, 11:4us.
*/
{0x04, 0x8a, 0x0c},
{0x04, 0x89, 0x08}, /* [3] RFD always on */
/*
* CTN lock in/out:
* 20000ppm/80000ppm. Lock out 2
* times.
*/
{0x04, 0x71, 0x2d},
/*
* 2.7G CDR settings
* NOF=40LSB for HBR CDR setting
*/
{0x04, 0x7d, 0x07},
{0x04, 0x7b, 0x00}, /* [1:0] Fmin=+4bands */
{0x04, 0x7a, 0xfd}, /* [7:5] DCO_FTRNG=+-40% */
/*
* 1.62G CDR settings
* [5:2]NOF=64LSB [1:0]DCO scale is 2/5
*/
{0x04, 0xc0, 0x12},
{0x04, 0xc1, 0x92}, /* Gitune=-37% */
{0x04, 0xc2, 0x1c}, /* Fbstep=100% */
{0x04, 0x32, 0x80}, /* [7] LOS signal disable */
/*
* RPIO Setting
* [7:4] LVDS driver bias current :
* 75% (250mV swing)
*/
{0x04, 0x00, 0xb0},
/*
* [7:6] Right-bar GPIO output strength is 8mA
*/
{0x04, 0x15, 0x40},
/* EQ Training State Machine Setting */
{0x04, 0x54, 0x10}, /* RCO calibration start */
/* [4:0] MAX_LANE_COUNT set to one lane */
{0x01, 0x02, 0x81},
/* [4:0] LANE_COUNT_SET set to one lane */
{0x01, 0x21, 0x81},
{0x00, 0x52, 0x20},
{0x00, 0xf1, 0x03}, /* HPD CP toggle enable */
{0x00, 0x62, 0x41},
/* Counter number, add 1ms counter delay */
{0x00, 0xf6, 0x01},
/*
* [6]PWM function control by
* DPCD0040f[7], default is PWM
* block always works.
*/
{0x00, 0x77, 0x06},
/*
* 04h Adjust VTotal tolerance to
* fix the 30Hz no display issue
*/
{0x00, 0x4c, 0x04},
/* DPCD00400='h00, Parade OUI = 'h001cf8 */
{0x01, 0xc0, 0x00},
{0x01, 0xc1, 0x1c}, /* DPCD00401='h1c */
{0x01, 0xc2, 0xf8}, /* DPCD00402='hf8 */
/*
* DPCD403~408 = ASCII code
* D2SLV5='h4432534c5635
*/
{0x01, 0xc3, 0x44},
{0x01, 0xc4, 0x32}, /* DPCD404 */
{0x01, 0xc5, 0x53}, /* DPCD405 */
{0x01, 0xc6, 0x4c}, /* DPCD406 */
{0x01, 0xc7, 0x56}, /* DPCD407 */
{0x01, 0xc8, 0x35}, /* DPCD408 */
/*
* DPCD40A, Initial Code major revision
* '01'
*/
{0x01, 0xca, 0x01},
/* DPCD40B, Initial Code minor revision '05' */
{0x01, 0xcb, 0x05},
/* DPCD720, Select internal PWM */
{0x01, 0xa5, 0xa0},
/*
* FFh for 100% PWM of brightness, 0h for 0%
* brightness
*/
{0x01, 0xa7, 0xff},
/*
* Set LVDS output as 6bit-VESA mapping,
* single LVDS channel
*/
{0x01, 0xcc, 0x13},
/* Enable SSC set by register */
{0x02, 0xb1, 0x20},
/*
* Set SSC enabled and +/-1% central
* spreading
*/
{0x04, 0x10, 0x16},
/* MPU Clock source: LC => RCO */
{0x04, 0x59, 0x60},
{0x04, 0x54, 0x14}, /* LC -> RCO */
{0x02, 0xa1, 0x91}, /* HPD high */
{END_OF_TABLE}
};
/**
* Write values table into the Parade eDP bridge
*
* @return 0 on success, non-0 on failure
*/
static int parade_write_regs(int base_addr, const struct reg_data *table)
{
int ret = 0;
while (!ret && (table->addr_off != END_OF_TABLE)) {
ret = i2c_write(base_addr + table->addr_off,
table->reg, 1,
(uint8_t *)&table->value,
sizeof(table->value));
table++;
}
return ret;
}
int parade_init(const void *blob)
{
struct gpio_desc rst_gpio;
struct gpio_desc slp_gpio;
int bus, old_bus;
int parent;
int node;
int addr;
int ret;
node = fdtdec_next_compatible(blob, 0, COMPAT_PARADE_PS8625);
if (node < 0)
return 0;
parent = fdt_parent_offset(blob, node);
if (parent < 0) {
debug("%s: Could not find parent i2c node\n", __func__);
return -1;
}
addr = fdtdec_get_int(blob, node, "reg", -1);
if (addr < 0) {
debug("%s: Could not find i2c address\n", __func__);
return -1;
}
gpio_request_by_name_nodev(blob, node, "sleep-gpio", 0, &slp_gpio,
GPIOD_IS_OUT | GPIOD_IS_OUT_ACTIVE);
mdelay(10);
gpio_request_by_name_nodev(blob, node, "reset-gpio", 0, &rst_gpio,
GPIOD_IS_OUT | GPIOD_IS_OUT_ACTIVE);
bus = i2c_get_bus_num_fdt(parent);
old_bus = i2c_get_bus_num();
debug("%s: Using i2c bus %d\n", __func__, bus);
/*
* TODO(sjg@chromium.org): Hmmm we seem to need some sort of delay
* here.
*/
mdelay(40);
i2c_set_bus_num(bus);
ret = parade_write_regs(addr, parade_values);
i2c_set_bus_num(old_bus);
return ret;
}