Nuttx currently has 2 types of sleep interfaces:
1. Signal-scheduled sleep: nxsig_sleep() / nxsig_usleep() / nxsig_nanosleep()
Weaknesses:
a. Signal-dependent: The signal-scheduled sleep method is bound to the signal framework, while some driver sleep operations do not depend on signals.
b. Timespec conversion: Signal-scheduled sleep involves timespec conversion, which has a significant impact on performance.
2. Busy sleep: up_mdelay() / up_udelay()
Weaknesses:
a. Does not actively trigger scheduling, occupy the CPU loading.
3. New interfaces: Scheduled sleep: nxsched_sleep() / nxsched_usleep() / nxsched_msleep() / nxsched_ticksleep()
Strengths:
a. Does not depend on the signal framework.
b. Tick-based, without additional computational overhead.
Currently, the Nuttx driver framework extensively uses nxsig_* interfaces. However, the driver does not need to rely on signals or timespec conversion.
Therefore, a new set of APIs is added to reduce dependencies on other modules.
(This PR also aims to make signals optional, further reducing the code size of Nuttx.)
Signed-off-by: chao an <anchao.archer@bytedance.com>
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
Add configuration and driver support for the SSD1681 1.54 inch e-paper display,
including the necessary waveforms and settings for proper operation. This extends
the existing SSD1680 e-paper driver to accommodate the new display module.
The changes involve updates to the Kconfig file for additional configuration options,
modifications to the driver implementation in ssd1680.c to include SSD1681 specific
logic, and updates to the header file ssd1680.h to reflect the added support.
Signed-off-by: Huang Qi <huangqi3@xiaomi.com>
Displays with resolution that is not multiplication of 8 had some issues in landscape mode (columns ware shifted).
Fixed function for copying bits.
Optimized memory reload for landscape mode.
In order to support multiple LCD instances per board, add a pointer from
lcd_planeinfo_s to the lcd_dev_s which it belongs to. Also enhance the
putrun, getrun, putarea and getarea methods to pass through the
lcd_dev_s pointer to the respective device driver.
Port all LCD device drivers to this lcd_planeinfo_s extension.
Enhance SSD1306 driver to support multiple LCDs.
Signed-off-by: Michael Jung <michael.jung@secore.ly>
