From 106b4a2a78b2a2f14885604891957b84bba502db Mon Sep 17 00:00:00 2001 From: Adrian Betschart Date: Fri, 11 Sep 2026 17:13:14 +0200 Subject: drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validation amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and uses the first encoding that validates. YCbCr 4:4:4 is listed before RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the "color format" property is left at AUTO, even though RGB fits the same link. That contradicts the documented AUTO behaviour for HDMI in enum drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when the bandwidth is not available or the mode is 4:2:0-only), which the amdgpu implementation of the property also describes. It also leaves the "Broadcast RGB" property without effect on such sinks, since the quantization range it selects only applies to RGB output. Try RGB first. The mask still holds every encoding the sink supports, so a mode that cannot carry RGB falls back exactly as before. For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI sink that advertised it. Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation") Suggested-by: Adolfo Rodrigues Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart Reviewed-by: Fangzhi Zuo Tested-by: Adolfo Rodrigues Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7) --- drivers/rtc/rtc-max8998.c | 321 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 321 insertions(+) create mode 100644 drivers/rtc/rtc-max8998.c (limited to 'drivers/rtc/rtc-max8998.c') diff --git a/drivers/rtc/rtc-max8998.c b/drivers/rtc/rtc-max8998.c new file mode 100644 index 000000000..a2c946edc --- /dev/null +++ b/drivers/rtc/rtc-max8998.c @@ -0,0 +1,321 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// RTC driver for Maxim MAX8998 +// +// Copyright (C) 2010 Samsung Electronics Co.Ltd +// Author: Minkyu Kang +// Author: Joonyoung Shim + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define MAX8998_RTC_SEC 0x00 +#define MAX8998_RTC_MIN 0x01 +#define MAX8998_RTC_HOUR 0x02 +#define MAX8998_RTC_WEEKDAY 0x03 +#define MAX8998_RTC_DATE 0x04 +#define MAX8998_RTC_MONTH 0x05 +#define MAX8998_RTC_YEAR1 0x06 +#define MAX8998_RTC_YEAR2 0x07 +#define MAX8998_ALARM0_SEC 0x08 +#define MAX8998_ALARM0_MIN 0x09 +#define MAX8998_ALARM0_HOUR 0x0a +#define MAX8998_ALARM0_WEEKDAY 0x0b +#define MAX8998_ALARM0_DATE 0x0c +#define MAX8998_ALARM0_MONTH 0x0d +#define MAX8998_ALARM0_YEAR1 0x0e +#define MAX8998_ALARM0_YEAR2 0x0f +#define MAX8998_ALARM1_SEC 0x10 +#define MAX8998_ALARM1_MIN 0x11 +#define MAX8998_ALARM1_HOUR 0x12 +#define MAX8998_ALARM1_WEEKDAY 0x13 +#define MAX8998_ALARM1_DATE 0x14 +#define MAX8998_ALARM1_MONTH 0x15 +#define MAX8998_ALARM1_YEAR1 0x16 +#define MAX8998_ALARM1_YEAR2 0x17 +#define MAX8998_ALARM0_CONF 0x18 +#define MAX8998_ALARM1_CONF 0x19 +#define MAX8998_RTC_STATUS 0x1a +#define MAX8998_WTSR_SMPL_CNTL 0x1b +#define MAX8998_TEST 0x1f + +#define HOUR_12 (1 << 7) +#define HOUR_PM (1 << 5) +#define ALARM0_STATUS (1 << 1) +#define ALARM1_STATUS (1 << 2) + +enum { + RTC_SEC = 0, + RTC_MIN, + RTC_HOUR, + RTC_WEEKDAY, + RTC_DATE, + RTC_MONTH, + RTC_YEAR1, + RTC_YEAR2, +}; + +struct max8998_rtc_info { + struct device *dev; + struct max8998_dev *max8998; + struct i2c_client *rtc; + struct rtc_device *rtc_dev; + int irq; + bool lp3974_bug_workaround; +}; + +static void max8998_data_to_tm(u8 *data, struct rtc_time *tm) +{ + tm->tm_sec = bcd2bin(data[RTC_SEC]); + tm->tm_min = bcd2bin(data[RTC_MIN]); + if (data[RTC_HOUR] & HOUR_12) { + tm->tm_hour = bcd2bin(data[RTC_HOUR] & 0x1f); + if (data[RTC_HOUR] & HOUR_PM) + tm->tm_hour += 12; + } else + tm->tm_hour = bcd2bin(data[RTC_HOUR] & 0x3f); + + tm->tm_wday = data[RTC_WEEKDAY] & 0x07; + tm->tm_mday = bcd2bin(data[RTC_DATE]); + tm->tm_mon = bcd2bin(data[RTC_MONTH]); + tm->tm_year = bcd2bin(data[RTC_YEAR1]) + bcd2bin(data[RTC_YEAR2]) * 100; + tm->tm_year -= 1900; +} + +static void max8998_tm_to_data(struct rtc_time *tm, u8 *data) +{ + data[RTC_SEC] = bin2bcd(tm->tm_sec); + data[RTC_MIN] = bin2bcd(tm->tm_min); + data[RTC_HOUR] = bin2bcd(tm->tm_hour); + data[RTC_WEEKDAY] = tm->tm_wday; + data[RTC_DATE] = bin2bcd(tm->tm_mday); + data[RTC_MONTH] = bin2bcd(tm->tm_mon); + data[RTC_YEAR1] = bin2bcd(tm->tm_year % 100); + data[RTC_YEAR2] = bin2bcd((tm->tm_year + 1900) / 100); +} + +static int max8998_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct max8998_rtc_info *info = dev_get_drvdata(dev); + u8 data[8]; + int ret; + + ret = max8998_bulk_read(info->rtc, MAX8998_RTC_SEC, 8, data); + if (ret < 0) + return ret; + + max8998_data_to_tm(data, tm); + + return 0; +} + +static int max8998_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct max8998_rtc_info *info = dev_get_drvdata(dev); + u8 data[8]; + int ret; + + max8998_tm_to_data(tm, data); + + ret = max8998_bulk_write(info->rtc, MAX8998_RTC_SEC, 8, data); + + if (info->lp3974_bug_workaround) + msleep(2000); + + return ret; +} + +static int max8998_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct max8998_rtc_info *info = dev_get_drvdata(dev); + u8 data[8]; + u8 val; + int ret; + + ret = max8998_bulk_read(info->rtc, MAX8998_ALARM0_SEC, 8, data); + if (ret < 0) + return ret; + + max8998_data_to_tm(data, &alrm->time); + + ret = max8998_read_reg(info->rtc, MAX8998_ALARM0_CONF, &val); + if (ret < 0) + return ret; + + alrm->enabled = !!val; + + ret = max8998_read_reg(info->rtc, MAX8998_RTC_STATUS, &val); + if (ret < 0) + return ret; + + if (val & ALARM0_STATUS) + alrm->pending = 1; + else + alrm->pending = 0; + + return 0; +} + +static int max8998_rtc_stop_alarm(struct max8998_rtc_info *info) +{ + int ret = max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, 0); + + if (info->lp3974_bug_workaround) + msleep(2000); + + return ret; +} + +static int max8998_rtc_start_alarm(struct max8998_rtc_info *info) +{ + int ret; + u8 alarm0_conf = 0x77; + + /* LP3974 with delay bug chips has rtc alarm bugs with "MONTH" field */ + if (info->lp3974_bug_workaround) + alarm0_conf = 0x57; + + ret = max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, alarm0_conf); + + if (info->lp3974_bug_workaround) + msleep(2000); + + return ret; +} + +static int max8998_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct max8998_rtc_info *info = dev_get_drvdata(dev); + u8 data[8]; + int ret; + + max8998_tm_to_data(&alrm->time, data); + + ret = max8998_rtc_stop_alarm(info); + if (ret < 0) + return ret; + + ret = max8998_bulk_write(info->rtc, MAX8998_ALARM0_SEC, 8, data); + if (ret < 0) + return ret; + + if (info->lp3974_bug_workaround) + msleep(2000); + + if (alrm->enabled) + ret = max8998_rtc_start_alarm(info); + + return ret; +} + +static int max8998_rtc_alarm_irq_enable(struct device *dev, + unsigned int enabled) +{ + struct max8998_rtc_info *info = dev_get_drvdata(dev); + + if (enabled) + return max8998_rtc_start_alarm(info); + else + return max8998_rtc_stop_alarm(info); +} + +static irqreturn_t max8998_rtc_alarm_irq(int irq, void *data) +{ + struct max8998_rtc_info *info = data; + + rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops max8998_rtc_ops = { + .read_time = max8998_rtc_read_time, + .set_time = max8998_rtc_set_time, + .read_alarm = max8998_rtc_read_alarm, + .set_alarm = max8998_rtc_set_alarm, + .alarm_irq_enable = max8998_rtc_alarm_irq_enable, +}; + +static int max8998_rtc_probe(struct platform_device *pdev) +{ + struct max8998_dev *max8998 = dev_get_drvdata(pdev->dev.parent); + struct max8998_platform_data *pdata = max8998->pdata; + struct max8998_rtc_info *info; + int ret; + + info = devm_kzalloc(&pdev->dev, sizeof(struct max8998_rtc_info), + GFP_KERNEL); + if (!info) + return -ENOMEM; + + info->dev = &pdev->dev; + info->max8998 = max8998; + info->rtc = max8998->rtc; + + platform_set_drvdata(pdev, info); + + info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8998-rtc", + &max8998_rtc_ops, THIS_MODULE); + + if (IS_ERR(info->rtc_dev)) { + ret = PTR_ERR(info->rtc_dev); + dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret); + return ret; + } + + if (!max8998->irq_domain) + goto no_irq; + + info->irq = irq_create_mapping(max8998->irq_domain, MAX8998_IRQ_ALARM0); + if (!info->irq) { + dev_warn(&pdev->dev, "Failed to map alarm IRQ\n"); + goto no_irq; + } + + ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL, + max8998_rtc_alarm_irq, 0, "rtc-alarm0", info); + + if (ret < 0) + dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n", + info->irq, ret); + +no_irq: + dev_info(&pdev->dev, "RTC CHIP NAME: %s\n", pdev->id_entry->name); + if (pdata && pdata->rtc_delay) { + info->lp3974_bug_workaround = true; + dev_warn(&pdev->dev, "LP3974 with RTC REGERR option." + " RTC updates will be extremely slow.\n"); + } + + return 0; +} + +static const struct platform_device_id max8998_rtc_id[] = { + { .name = "max8998-rtc", .driver_data = TYPE_MAX8998 }, + { .name = "lp3974-rtc", .driver_data = TYPE_LP3974 }, + { } +}; +MODULE_DEVICE_TABLE(platform, max8998_rtc_id); + +static struct platform_driver max8998_rtc_driver = { + .driver = { + .name = "max8998-rtc", + }, + .probe = max8998_rtc_probe, + .id_table = max8998_rtc_id, +}; + +module_platform_driver(max8998_rtc_driver); + +MODULE_AUTHOR("Minkyu Kang "); +MODULE_AUTHOR("Joonyoung Shim "); +MODULE_DESCRIPTION("Maxim MAX8998 RTC driver"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1