drivers/rtc/rtc-pcf2127.c

File Facts

System

Linux kernel

Corpus path

drivers/rtc/rtc-pcf2127.c

Extension

.c

Size

42547 bytes

Lines

1637

Domain

Driver Families

Bucket

drivers/rtc

Inferred role

Driver Families: exported/initcall integration point

Status

integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

• Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
• Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
• Touches IRQ or DMA behavior; this matters for the representative real-device path.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/i2c.h
• linux/spi/spi.h
• linux/bcd.h
• linux/bitfield.h
• linux/rtc.h
• linux/slab.h
• linux/module.h
• linux/of.h
• linux/of_irq.h
• linux/of_device.h
• linux/regmap.h
• linux/watchdog.h

Detected Declarations

• struct pcf21xx_ts_config
• struct pcf21xx_config
• struct pcf2127
• enum pcf21xx_type
• function pcf2127_rtc_read_time
• function pcf2127_rtc_set_time
• function pcf2127_param_get
• function pcf2127_param_set
• function pcf2127_rtc_ioctl
• function pcf2127_nvmem_read
• function pcf2127_nvmem_write
• function pcf2127_wdt_ping
• function pcf2127_wdt_active_ping
• function pcf2127_wdt_start
• function pcf2127_wdt_stop
• function pcf2127_wdt_set_timeout
• function pcf2127_watchdog_get_period
• function pcf2127_watchdog_init
• function pin
• function pcf2127_rtc_read_alarm
• function pcf2127_rtc_alarm_irq_enable
• function pcf2127_rtc_set_alarm
• function pcf2127_wdt_active_ping
• function pcf2127_rtc_ts_snapshot
• function pcf2127_rtc_irq
• function timestamp_store
• function timestamp0_store
• function timestamp1_store
• function timestamp2_store
• function timestamp3_store
• function timestamp_show
• function timestamp0_show
• function timestamp1_show
• function timestamp2_show
• function timestamp3_show
• function interrupt
• function pcf2127_configure_interrupt_pins
• function pcf2127_probe
• function pcf2127_i2c_write
• function pcf2127_i2c_gather_write
• function pcf2127_i2c_read
• function pcf2127_i2c_probe
• function pcf2127_i2c_register_driver
• function pcf2127_i2c_unregister_driver
• function pcf2127_i2c_register_driver
• function pcf2127_i2c_unregister_driver
• function pcf2127_spi_probe
• function pcf2127_spi_register_driver

Annotated Snippet

module_init(pcf2127_init)

static void __exit pcf2127_exit(void)
{
	pcf2127_spi_unregister_driver();
	pcf2127_i2c_unregister_driver();
}
module_exit(pcf2127_exit)

MODULE_AUTHOR("Renaud Cerrato <r.cerrato@til-technologies.fr>");
MODULE_DESCRIPTION("NXP PCF2127/29/31 RTC driver");
MODULE_LICENSE("GPL v2");

Annotation

• Immediate include surface: `linux/i2c.h`, `linux/spi/spi.h`, `linux/bcd.h`, `linux/bitfield.h`, `linux/rtc.h`, `linux/slab.h`, `linux/module.h`, `linux/of.h`.
• Detected declarations: `struct pcf21xx_ts_config`, `struct pcf21xx_config`, `struct pcf2127`, `enum pcf21xx_type`, `function pcf2127_rtc_read_time`, `function pcf2127_rtc_set_time`, `function pcf2127_param_get`, `function pcf2127_param_set`, `function pcf2127_rtc_ioctl`, `function pcf2127_nvmem_read`.
• Atlas domain: Driver Families / drivers/rtc.
• Implementation status: integration implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
• IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.