kernel/linux.git/drivers/rtc/rtc-abx80x.c, branch linux-7.1.y

rtc: abx80x: Disable alarm feature if no interrupt attached

2026-04-12T22:02:59+00:00

Commit 795cda8338ea ("rtc: interface: Fix long-standing race when setting alarm") exposed an issue where the rtc-abx80x driver does not clear the alarm feature bit, but instead relies on the set_alarm operation to return invalid. For example, when a RTC_UIE_ON ioctl is handled, it should abort at the feature validation. Instead, it proceeds to the rtc_timer_enqueue(), which used to return an error from the set_alarm call. However, following the race condition handling, which likely should not be discarding predecing errors, a success condition is returned to the ioctl() caller. This results in (for example): hwclock: select() to /dev/rtc0 to wait for clock tick timed out Notwithstanding the validity of the race condition handling, if an interrupt wasn't specified, or could not be attached, the driver should clear the alarm feature bit. Fixes: 718a820a303c ("rtc: abx80x: add alarm support") Signed-off-by: Anthony Pighin Link: https://patch.msgid.link/BN0PR08MB69510928028C933749F4139383D1A@BN0PR08MB6951.namprd08.prod.outlook.com Signed-off-by: Alexandre Belloni

rtc: abx80x: Remove use of i2c_match_id()

2026-03-12T14:15:22+00:00

The function i2c_match_id() is used to fetch the matching ID from the i2c_device_id table. This is often used to then retrieve the matching driver_data. This can be done in one step with the helper i2c_get_match_data(). This helper has a couple other benefits: * It doesn't need the i2c_device_id passed in so we do not need to have that forward declared, allowing us to remove those or move the i2c_device_id table down to its more natural spot with the other module info. * It also checks for device match data, which allows for OF and ACPI based probing. That means we do not have to manually check those first and can remove those checks. Signed-off-by: Andrew Davis Link: https://patch.msgid.link/20260305193545.796294-2-afd@ti.com Signed-off-by: Alexandre Belloni

rtc: abx80x: Fix WDT bit position of the status register

2024-11-11T21:10:26+00:00

The WDT bit in the status register is 5, not 6. This fixes from 6 to 5. Link: https://abracon.com/Support/AppsManuals/Precisiontiming/AB08XX-Application-Manual.pdf Link: https://www.microcrystal.com/fileadmin/Media/Products/RTC/App.Manual/RV-1805-C3_App-Manual.pdf Fixes: 749e36d0a0d7 ("rtc: abx80x: add basic watchdog support") Cc: Jeremy Gebben Signed-off-by: Nobuhiro Iwamatsu Link: https://lore.kernel.org/r/20241008041737.1640633-1-iwamatsu@nigauri.org Signed-off-by: Alexandre Belloni

rtc: abx80x: Fix return value of nvmem callback on read

2024-06-27T22:21:46+00:00

Read callbacks registered with nvmem core expect 0 to be returned on success and a negative value to be returned on failure. abx80x_nvmem_xfer() on read calls i2c_smbus_read_i2c_block_data() which returns the number of bytes read on success as per its api description, this return value is handled as an error and returned to nvmem even on success. Fix to handle all possible values that would be returned by i2c_smbus_read_i2c_block_data(). Fixes: e90ff8ede777 ("rtc: abx80x: Add nvmem support") Cc: stable@vger.kernel.org Signed-off-by: Joy Chakraborty Reviewed-by: Dan Carpenter Reviewed-by: Sean Anderson Link: https://lore.kernel.org/r/20240613120750.1455209-1-joychakr@google.com Signed-off-by: Alexandre Belloni

rtc: Explicitly include correct DT includes

2023-07-27T21:31:29+00:00

The DT of_device.h and of_platform.h date back to the separate of_platform_bus_type before it as merged into the regular platform bus. As part of that merge prepping Arm DT support 13 years ago, they "temporarily" include each other. They also include platform_device.h and of.h. As a result, there's a pretty much random mix of those include files used throughout the tree. In order to detangle these headers and replace the implicit includes with struct declarations, users need to explicitly include the correct includes. Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20230724205456.767430-1-robh@kernel.org Signed-off-by: Alexandre Belloni

rtc: Switch i2c drivers back to use .probe()

2023-06-06T21:29:37+00:00

After commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new() call-back type"), all drivers being converted to .probe_new() and then 03c835f498b5 ("i2c: Switch .probe() to not take an id parameter") convert back to (the new) .probe() to be able to eventually drop .probe_new() from struct i2c_driver. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20230505121136.1185653-1-u.kleine-koenig@pengutronix.de Signed-off-by: Alexandre Belloni

rtc: abx80x: Add nvmem support

2023-02-23T23:02:30+00:00

This adds support for the 256-byte internal RAM. There are two windows which can be used to access this RAM: 64 bytes at 0x40 (the "standard" address space) and 128 bytes at 0x80 (the "alternate" address space). We use the standard address space because it is also accessible over SPI (if such a port is ever done). We are limited to 32-byte reads for SMBus compatibility, so there's no advantage to using the alternate address space. There are some reserved bits in the EXTRAM register, and the datasheet doesn't say what to do with them. I've opted to skip a read/modify/write and just write the whole thing. If this driver is ever converted to regmap, this would be a good place to use regmap_update_bits. Signed-off-by: Sean Anderson Link: https://lore.kernel.org/r/20221222214532.1873718-1-sean.anderson@seco.com Signed-off-by: Alexandre Belloni

rtc: Include when appropriate

2022-11-15T20:01:51+00:00

The kstrto() functions have been moved from kernel.h to kstrtox.h. So, include the latter directly in the appropriate files. Signed-off-by: Christophe JAILLET Link: https://lore.kernel.org/r/786421fd0435a32206288904a1f879436a717529.1667721637.git.christophe.jaillet@wanadoo.fr Signed-off-by: Alexandre Belloni

rtc: abx80x: Convert to .probe_new()

2022-11-15T20:01:33+00:00

.probe_new() doesn't get the i2c_device_id * parameter, so determine that explicitly in .probe(). The device_id array has to move up for that to work. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20221021130706.178687-2-u.kleine-koenig@pengutronix.de Signed-off-by: Alexandre Belloni

rtc: abx80x: Add utility function for writing configuration key

2021-02-13T22:03:26+00:00

Writing one of key two values into the configuration key register is a common operation, so a utility function has been added to provide consistent behavior and eliminate code duplication. Signed-off-by: Kevin P. Fleming Cc: Alessandro Zummo Cc: Alexandre Belloni To: linux-rtc@vger.kernel.org Signed-off-by: Alexandre Belloni Link: https://lore.kernel.org/r/20200615105113.57770-2-kevin+linux@km6g.us