From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- 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