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-sd3078.c | 213 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 213 insertions(+) create mode 100644 drivers/rtc/rtc-sd3078.c (limited to 'drivers/rtc/rtc-sd3078.c') diff --git a/drivers/rtc/rtc-sd3078.c b/drivers/rtc/rtc-sd3078.c new file mode 100644 index 000000000..2c61f0e20 --- /dev/null +++ b/drivers/rtc/rtc-sd3078.c @@ -0,0 +1,213 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Real Time Clock (RTC) Driver for sd3078 + * Copyright (C) 2018 Zoro Li + */ + +#include +#include +#include +#include +#include +#include + +#define SD3078_REG_SC 0x00 +#define SD3078_REG_MN 0x01 +#define SD3078_REG_HR 0x02 +#define SD3078_REG_DW 0x03 +#define SD3078_REG_DM 0x04 +#define SD3078_REG_MO 0x05 +#define SD3078_REG_YR 0x06 + +#define SD3078_REG_CTRL1 0x0f +#define SD3078_REG_CTRL2 0x10 +#define SD3078_REG_CTRL3 0x11 + +#define KEY_WRITE1 0x80 +#define KEY_WRITE2 0x04 +#define KEY_WRITE3 0x80 + +#define NUM_TIME_REGS (SD3078_REG_YR - SD3078_REG_SC + 1) + +/* + * The sd3078 has write protection + * and we can choose whether or not to use it. + * Write protection is turned off by default. + */ +#define WRITE_PROTECT_EN 0 + +/* + * In order to prevent arbitrary modification of the time register, + * when modification of the register, + * the "write" bit needs to be written in a certain order. + * 1. set WRITE1 bit + * 2. set WRITE2 bit + * 3. set WRITE3 bit + */ +static void sd3078_enable_reg_write(struct regmap *regmap) +{ + regmap_update_bits(regmap, SD3078_REG_CTRL2, KEY_WRITE1, KEY_WRITE1); + regmap_update_bits(regmap, SD3078_REG_CTRL1, KEY_WRITE2, KEY_WRITE2); + regmap_update_bits(regmap, SD3078_REG_CTRL1, KEY_WRITE3, KEY_WRITE3); +} + +#if WRITE_PROTECT_EN +/* + * In order to prevent arbitrary modification of the time register, + * we should disable the write function. + * when disable write, + * the "write" bit needs to be clear in a certain order. + * 1. clear WRITE2 bit + * 2. clear WRITE3 bit + * 3. clear WRITE1 bit + */ +static void sd3078_disable_reg_write(struct regmap *regmap) +{ + regmap_update_bits(regmap, SD3078_REG_CTRL1, KEY_WRITE2, 0); + regmap_update_bits(regmap, SD3078_REG_CTRL1, KEY_WRITE3, 0); + regmap_update_bits(regmap, SD3078_REG_CTRL2, KEY_WRITE1, 0); +} +#endif + +static int sd3078_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + unsigned char hour; + unsigned char rtc_data[NUM_TIME_REGS] = {0}; + struct i2c_client *client = to_i2c_client(dev); + struct regmap *regmap = i2c_get_clientdata(client); + int ret; + + ret = regmap_bulk_read(regmap, SD3078_REG_SC, rtc_data, NUM_TIME_REGS); + if (ret < 0) { + dev_err(dev, "reading from RTC failed with err:%d\n", ret); + return ret; + } + + tm->tm_sec = bcd2bin(rtc_data[SD3078_REG_SC] & 0x7F); + tm->tm_min = bcd2bin(rtc_data[SD3078_REG_MN] & 0x7F); + + /* + * The sd3078 supports 12/24 hour mode. + * When getting time, + * we need to convert the 12 hour mode to the 24 hour mode. + */ + hour = rtc_data[SD3078_REG_HR]; + if (hour & 0x80) /* 24H MODE */ + tm->tm_hour = bcd2bin(rtc_data[SD3078_REG_HR] & 0x3F); + else if (hour & 0x20) /* 12H MODE PM */ + tm->tm_hour = bcd2bin(rtc_data[SD3078_REG_HR] & 0x1F) + 12; + else /* 12H MODE AM */ + tm->tm_hour = bcd2bin(rtc_data[SD3078_REG_HR] & 0x1F); + + tm->tm_mday = bcd2bin(rtc_data[SD3078_REG_DM] & 0x3F); + tm->tm_wday = rtc_data[SD3078_REG_DW] & 0x07; + tm->tm_mon = bcd2bin(rtc_data[SD3078_REG_MO] & 0x1F) - 1; + tm->tm_year = bcd2bin(rtc_data[SD3078_REG_YR]) + 100; + + return 0; +} + +static int sd3078_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + unsigned char rtc_data[NUM_TIME_REGS]; + struct i2c_client *client = to_i2c_client(dev); + struct regmap *regmap = i2c_get_clientdata(client); + int ret; + + rtc_data[SD3078_REG_SC] = bin2bcd(tm->tm_sec); + rtc_data[SD3078_REG_MN] = bin2bcd(tm->tm_min); + rtc_data[SD3078_REG_HR] = bin2bcd(tm->tm_hour) | 0x80; + rtc_data[SD3078_REG_DM] = bin2bcd(tm->tm_mday); + rtc_data[SD3078_REG_DW] = tm->tm_wday & 0x07; + rtc_data[SD3078_REG_MO] = bin2bcd(tm->tm_mon) + 1; + rtc_data[SD3078_REG_YR] = bin2bcd(tm->tm_year - 100); + +#if WRITE_PROTECT_EN + sd3078_enable_reg_write(regmap); +#endif + + ret = regmap_bulk_write(regmap, SD3078_REG_SC, rtc_data, + NUM_TIME_REGS); + if (ret < 0) { + dev_err(dev, "writing to RTC failed with err:%d\n", ret); + return ret; + } + +#if WRITE_PROTECT_EN + sd3078_disable_reg_write(regmap); +#endif + + return 0; +} + +static const struct rtc_class_ops sd3078_rtc_ops = { + .read_time = sd3078_rtc_read_time, + .set_time = sd3078_rtc_set_time, +}; + +static const struct regmap_config regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = 0x11, +}; + +static int sd3078_probe(struct i2c_client *client) +{ + int ret; + struct regmap *regmap; + struct rtc_device *rtc; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) + return -ENODEV; + + regmap = devm_regmap_init_i2c(client, ®map_config); + if (IS_ERR(regmap)) { + dev_err(&client->dev, "regmap allocation failed\n"); + return PTR_ERR(regmap); + } + + i2c_set_clientdata(client, regmap); + + rtc = devm_rtc_allocate_device(&client->dev); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + + rtc->ops = &sd3078_rtc_ops; + rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; + rtc->range_max = RTC_TIMESTAMP_END_2099; + + ret = devm_rtc_register_device(rtc); + if (ret) + return ret; + + sd3078_enable_reg_write(regmap); + + return 0; +} + +static const struct i2c_device_id sd3078_id[] = { + { .name = "sd3078" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, sd3078_id); + +static const __maybe_unused struct of_device_id rtc_dt_match[] = { + { .compatible = "whwave,sd3078" }, + {}, +}; +MODULE_DEVICE_TABLE(of, rtc_dt_match); + +static struct i2c_driver sd3078_driver = { + .driver = { + .name = "sd3078", + .of_match_table = of_match_ptr(rtc_dt_match), + }, + .probe = sd3078_probe, + .id_table = sd3078_id, +}; + +module_i2c_driver(sd3078_driver); + +MODULE_AUTHOR("Dianlong Li "); +MODULE_DESCRIPTION("SD3078 RTC driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1