rtd2132: Add driver for Realtek RTD2132 LVDS bridge

This driver allows the mainboard to enable spread spectrum
clocking at 0.5%, 1.0%, and 1.5% with devicetree settings.

Change-Id: I59c61e67aa8e951fd9904ad951deb6d0ba29669e
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/61894
Reviewed-on: http://review.coreboot.org/4365
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
Tested-by: build bot (Jenkins)
This commit is contained in:
Duncan Laurie 2013-07-15 09:11:21 -07:00 committed by Patrick Georgi
parent 8870733b59
commit 0cf0d1499a
6 changed files with 184 additions and 0 deletions

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@ -4,5 +4,6 @@ source src/drivers/i2c/adt7463/Kconfig
source src/drivers/i2c/i2cmux/Kconfig
source src/drivers/i2c/i2cmux2/Kconfig
source src/drivers/i2c/lm63/Kconfig
source src/drivers/i2c/rtd2132/Kconfig
source src/drivers/i2c/w83795/Kconfig
source src/drivers/i2c/w83793/Kconfig

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@ -4,5 +4,6 @@ subdirs-y += adt7463
subdirs-y += i2cmux
subdirs-y += i2cmux2
subdirs-y += lm63
subdirs-y += rtd2132
subdirs-y += w83795
subdirs-y += w83793

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@ -0,0 +1,5 @@
config DRIVERS_I2C_RTD2132
bool
default n
help
Enable support for Realtek RTD2132 DisplayPort to LVDS bridge chip.

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@ -0,0 +1 @@
ramstage-$(CONFIG_DRIVERS_I2C_RTD2132) += rtd2132.c

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@ -0,0 +1,29 @@
/*
* This file is part of the coreboot project.
*
* Copyright 2013 Google Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
*/
struct drivers_i2c_rtd2132_config {
/*
* LVDS Spread Spectrum Clock
* 0x00 = DISABLED
* 0x05 = 0.5%
* 0x10 = 1.0%
* 0x15 = 1.5%
*/
u8 sscg_percent;
};

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@ -0,0 +1,147 @@
/*
* This file is part of the coreboot project.
*
* Copyright 2013 Google Inc. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
*/
#include <console/console.h>
#include <delay.h>
#include <device/device.h>
#include <device/smbus.h>
#include <device/pci.h>
#include "chip.h"
/* Chip commands */
#define RTD2132_COMMAND 0x01
#define RTD2132_DATA 0x00
#define RTD2132_FIRMWARE 0x80
#define RTD2132_FIRMWARE_START 0x00
#define RTD2132_FIRMWARE_STOP 0x01
/* Spread spectrum configuration */
#define RTD2132_COMMAND_SSCG_CONFIG_0 0x39
#define RTD2132_SSCG_ENABLE 0xa0
#define RTD2132_SSCG_DISABLE 0x20
#define RTD2132_COMMAND_SSCG_CONFIG_1 0x3a
#define RTD2132_SSCG_CONFIG_DISABLED 0x01 /* DISABLED */
#define RTD2132_SSCG_CONFIG_0_5 0x07 /* 0.5% */
#define RTD2132_SSCG_CONFIG_1_0 0x0f /* 1.0% */
#define RTD2132_SSCG_CONFIG_1_5 0x16 /* 1.5% */
/* Configuration values from devicetree */
#define RTD2132_SSCG_PERCENT_0_0 0x00 /* DISABLED */
#define RTD2132_SSCG_PERCENT_0_5 0x05 /* 0.5% */
#define RTD2132_SSCG_PERCENT_1_0 0x10 /* 1.0% */
#define RTD2132_SSCG_PERCENT_1_5 0x15 /* 1.5% */
static void rtd2132_firmware_stop(device_t dev)
{
smbus_write_byte(dev, RTD2132_FIRMWARE, RTD2132_FIRMWARE_STOP);
mdelay(2);
}
static void rtd2132_firmware_start(device_t dev)
{
smbus_write_byte(dev, RTD2132_FIRMWARE, RTD2132_FIRMWARE_START);
}
static void rtd2132_sscg_enable(device_t dev, u8 sscg_percent)
{
/* SSCG_Config_0 */
smbus_write_byte(dev, RTD2132_COMMAND, RTD2132_COMMAND_SSCG_CONFIG_0);
smbus_write_byte(dev, RTD2132_DATA, RTD2132_SSCG_ENABLE);
/* SSCG_Config_1 */
smbus_write_byte(dev, RTD2132_COMMAND, RTD2132_COMMAND_SSCG_CONFIG_1);
smbus_write_byte(dev, RTD2132_DATA, sscg_percent);
}
static void rtd2132_sscg_disable(device_t dev)
{
/* SSCG_Config_0 */
smbus_write_byte(dev, RTD2132_COMMAND, RTD2132_COMMAND_SSCG_CONFIG_0);
smbus_write_byte(dev, RTD2132_DATA, RTD2132_SSCG_DISABLE);
/* SSCG_Config_1 */
smbus_write_byte(dev, RTD2132_COMMAND, RTD2132_COMMAND_SSCG_CONFIG_1);
smbus_write_byte(dev, RTD2132_DATA, RTD2132_SSCG_CONFIG_DISABLED);
}
static void rtd2132_setup(device_t dev)
{
struct drivers_i2c_rtd2132_config *config = dev->chip_info;
if (!config)
return;
/* Stop running firmware */
rtd2132_firmware_stop(dev);
/* Spread spectrum configuration */
switch (config->sscg_percent) {
case RTD2132_SSCG_PERCENT_0_0:
printk(BIOS_INFO, "RTD2132: Disable Spread Spectrum\n");
rtd2132_sscg_disable(dev);
break;
case RTD2132_SSCG_PERCENT_0_5:
printk(BIOS_INFO, "RTD2132: Enable 0.5%% Spread Spectrum\n");
rtd2132_sscg_enable(dev, RTD2132_SSCG_CONFIG_0_5);
break;
case RTD2132_SSCG_PERCENT_1_0:
printk(BIOS_INFO, "RTD2132: Enable 1.0%% Spread Spectrum\n");
rtd2132_sscg_enable(dev, RTD2132_SSCG_CONFIG_1_0);
break;
case RTD2132_SSCG_PERCENT_1_5:
printk(BIOS_INFO, "RTD2132: Enable 1.5%% Spread Spectrum\n");
rtd2132_sscg_enable(dev, RTD2132_SSCG_CONFIG_1_5);
break;
default:
printk(BIOS_ERR, "RTD2132: Invalid Spread Spectrum 0x%02x\n",
config->sscg_percent);
}
/* Start firmware */
rtd2132_firmware_start(dev);
}
static void rtd2132_init(device_t dev)
{
if (dev->enabled && dev->path.type == DEVICE_PATH_I2C &&
ops_smbus_bus(get_pbus_smbus(dev))) {
rtd2132_setup(dev);
}
}
static void rtd2132_noop(device_t dummy)
{
}
static struct device_operations rtd2132_operations = {
.read_resources = rtd2132_noop,
.set_resources = rtd2132_noop,
.enable_resources = rtd2132_noop,
.init = rtd2132_init,
};
static void enable_dev(struct device *dev)
{
dev->ops = &rtd2132_operations;
}
struct chip_operations drivers_i2c_rtd2132_ops = {
CHIP_NAME("Realtek RTD2132 LVDS Bridge")
.enable_dev = enable_dev,
};