kernel/linux.git/drivers/rtc/rtc-pcf2127.c, branch v7.0.10

rtc: pcf2127: fix watchdog interrupt mask on pcf2131

2025-10-05T21:30:10+00:00

When using interrupt pin (INT A) as watchdog output all other interrupt sources need to be disabled to avoid additional resets. Resulting INT_A_MASK1 value is 55 (0x37). Signed-off-by: Bruno Thomsen Link: https://lore.kernel.org/r/20250902182235.6825-1-bruno.thomsen@gmail.com Signed-off-by: Alexandre Belloni

rtc: pcf2127: clear minute/second interrupt

2025-09-16T15:38:21+00:00

PCF2127 can generate interrupt every full second or minute configured from control and status register 1, bits MI (1) and SI (0). On interrupt control register 2 bit MSF (7) is set and must be cleared to continue normal operation. While the driver never enables this interrupt on its own, users or firmware may do so - e.g. as an easy way to test the interrupt. Add preprocessor definition for MSF bit and include it in the irq bitmask to ensure minute and second interrupts are cleared when fired. This fixes an issue where the rtc enters a test mode and becomes unresponsive after a second interrupt has fired and is not cleared in time. In this state register writes to control registers have no effect and the interrupt line is kept asserted [1]: [1] userspace commands to put rtc into unresponsive state: $ i2cget -f -y 2 0x51 0x00 0x04 $ i2cset -f -y 2 0x51 0x00 0x05 # set bit 0 SI $ i2cget -f -y 2 0x51 0x00 0x84 # bit 8 EXT_TEST set $ i2cset -f -y 2 0x51 0x00 0x05 # try overwrite control register $ i2cget -f -y 2 0x51 0x00 0x84 # no change Signed-off-by: Josua Mayer Reviewed-by: Bruno Thomsen Link: https://lore.kernel.org/r/20250825-rtc-irq-v1-1-0133319406a7@solid-run.com Signed-off-by: Alexandre Belloni

rtc: pcf2127: add missing semicolon after statement

2025-06-24T14:06:14+00:00

Replace comma with semicolon at the end of the statement when setting config.max_register. Fixes: fd28ceb4603f ("rtc: pcf2127: add variant-specific configuration structure") Cc: stable@vger.kernel.org Cc: Elena Popa Signed-off-by: Hugo Villeneuve Link: https://lore.kernel.org/r/20250529202923.1552560-1-hugo@hugovil.com Signed-off-by: Alexandre Belloni

rtc: pcf2127: fix SPI command byte for PCF2131

2025-06-24T14:04:42+00:00

PCF2131 was not responding to read/write operations using SPI. PCF2131 has a different command byte definition, compared to PCF2127/29. Added the new command byte definition when PCF2131 is detected. Fixes: afc505bf9039 ("rtc: pcf2127: add support for PCF2131 RTC") Cc: stable@vger.kernel.org Signed-off-by: Elena Popa Acked-by: Hugo Villeneuve Link: https://lore.kernel.org/r/20250530104001.957977-1-elena.popa@nxp.com Signed-off-by: Alexandre Belloni

rtc: pcf2127: add BSM support

2025-01-28T23:42:29+00:00

The pcf2127 encodes BSM, BLD and power fail detection in the same set of bits so it is necessary to do some calculation when changing BSM to keep the rest of the configuration as-is. However, when BSM is disabled, there is no configuration with BLD enabled so this will be lost when coming back to a mode with BSM enabled. Link: https://lore.kernel.org/r/20250127162728.86234-1-alexandre.belloni@bootlin.com Signed-off-by: Alexandre Belloni

rtc: pcf2127: remove useless check

2023-08-27T21:53:06+00:00

This check is only useful when introducing support for a new RTC in the driver. Cut down the number of strings in th driver. Link: https://lore.kernel.org/r/20230827214649.537095-1-alexandre.belloni@bootlin.com Signed-off-by: Alexandre Belloni

rtc: pcf2127: remove unused function argument

2023-08-16T23:01:51+00:00

Fixes the following W=1 kernel build warning(s): drivers/rtc/rtc-pcf2127.c: In function ‘pcf2127_probe’: drivers/rtc/rtc-pcf2127.c:635:32: warning: unused parameter ‘name’ [-Wunused-parameter] 635 | int alarm_irq, const char *name, bool is_pcf2127) | ~~~~~~~~~~~~^~~~ Signed-off-by: Hugo Villeneuve Link: https://lore.kernel.org/r/20230801190432.3340545-1-hugo@hugovil.com Signed-off-by: Alexandre Belloni

rtc: pcf2127: add error checking when disabling POR0

2023-08-16T23:01:24+00:00

If PCF2127 device is absent from the I2C bus, or if there is a communication problem, disabling POR0 may fail silently and we still continue with probing the device. In that case, abort probe operation. Signed-off-by: Hugo Villeneuve Link: https://lore.kernel.org/r/20230728171211.3016019-1-hugo@hugovil.com Signed-off-by: Alexandre Belloni

rtc: pcf2127: fix error code in pcf2127_enable_ts()

2023-08-16T22:58:35+00:00

This error path accidentally returns success. Return -EINVAL instead. Fixes: 420cc9e850db ("rtc: pcf2127: add support for multiple TS functions") Signed-off-by: Dan Carpenter Reviewed-by: Bruno Thomsen Reviewed-by: Hugo Villeneuve Reviewed-by: Hugo Villeneuve Link: https://lore.kernel.org/r/55b9c84b-9d21-444f-b91a-cf9316b65833@moroto.mountain Signed-off-by: Alexandre Belloni

rtc: pcf2127: add UIE support for PCF2131

2023-07-27T20:54:53+00:00

The PCF2127/29 do NOT support alarms with a 1 second resolution, but the PCF2131 does. Signed-off-by: Hugo Villeneuve Link: https://lore.kernel.org/r/20230622145800.2442116-17-hugo@hugovil.com Signed-off-by: Alexandre Belloni