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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /drivers/rtc/rtc-em3027.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
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
...
Diffstat (limited to 'drivers/rtc/rtc-em3027.c')
| -rw-r--r-- | drivers/rtc/rtc-em3027.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-em3027.c b/drivers/rtc/rtc-em3027.c new file mode 100644 index 000000000..d555e5d59 --- /dev/null +++ b/drivers/rtc/rtc-em3027.c @@ -0,0 +1,158 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * An rtc/i2c driver for the EM Microelectronic EM3027 + * Copyright 2011 CompuLab, Ltd. + * + * Author: Mike Rapoport <mike@compulab.co.il> + * + * Based on rtc-ds1672.c by Alessandro Zummo <a.zummo@towertech.it> + */ + +#include <linux/i2c.h> +#include <linux/rtc.h> +#include <linux/bcd.h> +#include <linux/module.h> +#include <linux/of.h> + +/* Registers */ +#define EM3027_REG_ON_OFF_CTRL 0x00 +#define EM3027_REG_IRQ_CTRL 0x01 +#define EM3027_REG_IRQ_FLAGS 0x02 +#define EM3027_REG_STATUS 0x03 +#define EM3027_REG_RST_CTRL 0x04 + +#define EM3027_REG_WATCH_SEC 0x08 +#define EM3027_REG_WATCH_MIN 0x09 +#define EM3027_REG_WATCH_HOUR 0x0a +#define EM3027_REG_WATCH_DATE 0x0b +#define EM3027_REG_WATCH_DAY 0x0c +#define EM3027_REG_WATCH_MON 0x0d +#define EM3027_REG_WATCH_YEAR 0x0e + +#define EM3027_REG_ALARM_SEC 0x10 +#define EM3027_REG_ALARM_MIN 0x11 +#define EM3027_REG_ALARM_HOUR 0x12 +#define EM3027_REG_ALARM_DATE 0x13 +#define EM3027_REG_ALARM_DAY 0x14 +#define EM3027_REG_ALARM_MON 0x15 +#define EM3027_REG_ALARM_YEAR 0x16 + +static struct i2c_driver em3027_driver; + +static int em3027_get_time(struct device *dev, struct rtc_time *tm) +{ + struct i2c_client *client = to_i2c_client(dev); + + unsigned char addr = EM3027_REG_WATCH_SEC; + unsigned char buf[7]; + + struct i2c_msg msgs[] = { + {/* setup read addr */ + .addr = client->addr, + .len = 1, + .buf = &addr + }, + {/* read time/date */ + .addr = client->addr, + .flags = I2C_M_RD, + .len = 7, + .buf = buf + }, + }; + + /* read time/date registers */ + if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) { + dev_err(&client->dev, "%s: read error\n", __func__); + return -EIO; + } + + tm->tm_sec = bcd2bin(buf[0]); + tm->tm_min = bcd2bin(buf[1]); + tm->tm_hour = bcd2bin(buf[2]); + tm->tm_mday = bcd2bin(buf[3]); + tm->tm_wday = bcd2bin(buf[4]); + tm->tm_mon = bcd2bin(buf[5]) - 1; + tm->tm_year = bcd2bin(buf[6]) + 100; + + return 0; +} + +static int em3027_set_time(struct device *dev, struct rtc_time *tm) +{ + struct i2c_client *client = to_i2c_client(dev); + unsigned char buf[8]; + + struct i2c_msg msg = { + .addr = client->addr, + .len = 8, + .buf = buf, /* write time/date */ + }; + + buf[0] = EM3027_REG_WATCH_SEC; + buf[1] = bin2bcd(tm->tm_sec); + buf[2] = bin2bcd(tm->tm_min); + buf[3] = bin2bcd(tm->tm_hour); + buf[4] = bin2bcd(tm->tm_mday); + buf[5] = bin2bcd(tm->tm_wday); + buf[6] = bin2bcd(tm->tm_mon + 1); + buf[7] = bin2bcd(tm->tm_year % 100); + + /* write time/date registers */ + if ((i2c_transfer(client->adapter, &msg, 1)) != 1) { + dev_err(&client->dev, "%s: write error\n", __func__); + return -EIO; + } + + return 0; +} + +static const struct rtc_class_ops em3027_rtc_ops = { + .read_time = em3027_get_time, + .set_time = em3027_set_time, +}; + +static int em3027_probe(struct i2c_client *client) +{ + struct rtc_device *rtc; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) + return -ENODEV; + + rtc = devm_rtc_device_register(&client->dev, em3027_driver.driver.name, + &em3027_rtc_ops, THIS_MODULE); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + + i2c_set_clientdata(client, rtc); + + return 0; +} + +static const struct i2c_device_id em3027_id[] = { + { .name = "em3027" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, em3027_id); + +#ifdef CONFIG_OF +static const struct of_device_id em3027_of_match[] = { + { .compatible = "emmicro,em3027", }, + {} +}; +MODULE_DEVICE_TABLE(of, em3027_of_match); +#endif + +static struct i2c_driver em3027_driver = { + .driver = { + .name = "rtc-em3027", + .of_match_table = of_match_ptr(em3027_of_match), + }, + .probe = em3027_probe, + .id_table = em3027_id, +}; + +module_i2c_driver(em3027_driver); + +MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>"); +MODULE_DESCRIPTION("EM Microelectronic EM3027 RTC driver"); +MODULE_LICENSE("GPL"); |
