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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-r9701.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-r9701.c')
| -rw-r--r-- | drivers/rtc/rtc-r9701.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-r9701.c b/drivers/rtc/rtc-r9701.c new file mode 100644 index 000000000..60a3c3d74 --- /dev/null +++ b/drivers/rtc/rtc-r9701.c @@ -0,0 +1,145 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for Epson RTC-9701JE + * + * Copyright (C) 2008 Magnus Damm + * + * Based on rtc-max6902.c + * + * Copyright (C) 2006 8D Technologies inc. + * Copyright (C) 2004 Compulab Ltd. + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/device.h> +#include <linux/init.h> +#include <linux/rtc.h> +#include <linux/spi/spi.h> +#include <linux/bcd.h> +#include <linux/delay.h> +#include <linux/bitops.h> + +#define RSECCNT 0x00 /* Second Counter */ +#define RMINCNT 0x01 /* Minute Counter */ +#define RHRCNT 0x02 /* Hour Counter */ +#define RWKCNT 0x03 /* Week Counter */ +#define RDAYCNT 0x04 /* Day Counter */ +#define RMONCNT 0x05 /* Month Counter */ +#define RYRCNT 0x06 /* Year Counter */ +#define R100CNT 0x07 /* Y100 Counter */ +#define RMINAR 0x08 /* Minute Alarm */ +#define RHRAR 0x09 /* Hour Alarm */ +#define RWKAR 0x0a /* Week/Day Alarm */ +#define RTIMCNT 0x0c /* Interval Timer */ +#define REXT 0x0d /* Extension Register */ +#define RFLAG 0x0e /* RTC Flag Register */ +#define RCR 0x0f /* RTC Control Register */ + +static int write_reg(struct device *dev, int address, unsigned char data) +{ + struct spi_device *spi = to_spi_device(dev); + unsigned char buf[2]; + + buf[0] = address & 0x7f; + buf[1] = data; + + return spi_write(spi, buf, ARRAY_SIZE(buf)); +} + +static int read_regs(struct device *dev, unsigned char *regs, int no_regs) +{ + struct spi_device *spi = to_spi_device(dev); + u8 txbuf[1], rxbuf[1]; + int k, ret; + + ret = 0; + + for (k = 0; ret == 0 && k < no_regs; k++) { + txbuf[0] = 0x80 | regs[k]; + ret = spi_write_then_read(spi, txbuf, 1, rxbuf, 1); + regs[k] = rxbuf[0]; + } + + return ret; +} + +static int r9701_get_datetime(struct device *dev, struct rtc_time *dt) +{ + int ret; + unsigned char buf[] = { RSECCNT, RMINCNT, RHRCNT, + RDAYCNT, RMONCNT, RYRCNT }; + + ret = read_regs(dev, buf, ARRAY_SIZE(buf)); + if (ret) + return ret; + + dt->tm_sec = bcd2bin(buf[0]); /* RSECCNT */ + dt->tm_min = bcd2bin(buf[1]); /* RMINCNT */ + dt->tm_hour = bcd2bin(buf[2]); /* RHRCNT */ + + dt->tm_mday = bcd2bin(buf[3]); /* RDAYCNT */ + dt->tm_mon = bcd2bin(buf[4]) - 1; /* RMONCNT */ + dt->tm_year = bcd2bin(buf[5]) + 100; /* RYRCNT */ + + return 0; +} + +static int r9701_set_datetime(struct device *dev, struct rtc_time *dt) +{ + int ret; + + ret = write_reg(dev, RHRCNT, bin2bcd(dt->tm_hour)); + ret = ret ? ret : write_reg(dev, RMINCNT, bin2bcd(dt->tm_min)); + ret = ret ? ret : write_reg(dev, RSECCNT, bin2bcd(dt->tm_sec)); + ret = ret ? ret : write_reg(dev, RDAYCNT, bin2bcd(dt->tm_mday)); + ret = ret ? ret : write_reg(dev, RMONCNT, bin2bcd(dt->tm_mon + 1)); + ret = ret ? ret : write_reg(dev, RYRCNT, bin2bcd(dt->tm_year - 100)); + + return ret; +} + +static const struct rtc_class_ops r9701_rtc_ops = { + .read_time = r9701_get_datetime, + .set_time = r9701_set_datetime, +}; + +static int r9701_probe(struct spi_device *spi) +{ + struct rtc_device *rtc; + unsigned char tmp; + int res; + + tmp = R100CNT; + res = read_regs(&spi->dev, &tmp, 1); + if (res || tmp != 0x20) { + dev_err(&spi->dev, "cannot read RTC register\n"); + return -ENODEV; + } + + rtc = devm_rtc_allocate_device(&spi->dev); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + + spi_set_drvdata(spi, rtc); + rtc->ops = &r9701_rtc_ops; + rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; + rtc->range_max = RTC_TIMESTAMP_END_2099; + + return devm_rtc_register_device(rtc); +} + +static struct spi_driver r9701_driver = { + .driver = { + .name = "rtc-r9701", + }, + .probe = r9701_probe, +}; + +module_spi_driver(r9701_driver); + +MODULE_DESCRIPTION("r9701 spi RTC driver"); +MODULE_AUTHOR("Magnus Damm <damm@opensource.se>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("spi:rtc-r9701"); |
