ff1e858180
Most prominently, add support for a transfer where a write with no-stop
flag is followed by a write with no-start flag. Logically, it's a
single larger write, but consumers may want to split it like that
because one part can be a register ID and the other part can be data to
be written to (or starting at) that register.
Such a transfer can be created by i2c tool and iic(4) driver, e.g., for
an EEPROM write at specific offset:
i2c -m tr -a 0x50 -d w -w 16 -o 0 -c 8 -v < /dev/random
This should be fixed by new code that handles the end of data transfer
for both reads and writes. It handles two existing conditions and one
new. Namely:
- the last message has been completed -- end of transfer;
- a message has been completed and the next one requires the start
condition;
- a message has been completed and the next one should be sent without
the start condition.
In the last case we simply switch to the next message and start sending
its data. Reads without the start condition are not supported yet,
though. That's because we NACK the last byte of the previous message,
so the device stops sending data. To fix this we will need to add a
look-ahead at the next message when handling the penultimate byte of the
current one.
This change also fixed a bug where msg_idx was not incremented after a
read message. Apparently, typically a read message is a last message in
a transfer, so the bug did not cause much trouble.
PR: 258994
MFC after: 3 weeks
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| .cirrus-ci | ||
| .github | ||
| bin | ||
| cddl | ||
| contrib | ||
| crypto | ||
| etc | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| rescue | ||
| sbin | ||
| secure | ||
| share | ||
| stand | ||
| sys | ||
| targets | ||
| tests | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| .arcconfig | ||
| .arclint | ||
| .cirrus.yml | ||
| .clang-format | ||
| .gitattributes | ||
| .gitignore | ||
| COPYRIGHT | ||
| LOCKS | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| Makefile.libcompat | ||
| Makefile.sys.inc | ||
| ObsoleteFiles.inc | ||
| README.md | ||
| RELNOTES | ||
| UPDATING | ||
FreeBSD Source:
This is the top level of the FreeBSD source directory.
FreeBSD is an operating system used to power modern servers, desktops, and embedded platforms. A large community has continually developed it for more than thirty years. Its advanced networking, security, and storage features have made FreeBSD the platform of choice for many of the busiest web sites and most pervasive embedded networking and storage devices.
For copyright information, please see the file COPYRIGHT in this directory. Additional copyright information also exists for some sources in this tree - please see the specific source directories for more information.
The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree. See build(7), config(8), FreeBSD handbook on building userland, and Handbook for kernels for more information, including setting make(1) variables.
Source Roadmap:
| Directory | Description |
|---|---|
| bin | System/user commands. |
| cddl | Various commands and libraries under the Common Development and Distribution License. |
| contrib | Packages contributed by 3rd parties. |
| crypto | Cryptography stuff (see crypto/README). |
| etc | Template files for /etc. |
| gnu | Various commands and libraries under the GNU Public License. Please see gnu/COPYING and gnu/COPYING.LIB for more information. |
| include | System include files. |
| kerberos5 | Kerberos5 (Heimdal) package. |
| lib | System libraries. |
| libexec | System daemons. |
| release | Release building Makefile & associated tools. |
| rescue | Build system for statically linked /rescue utilities. |
| sbin | System commands. |
| secure | Cryptographic libraries and commands. |
| share | Shared resources. |
| stand | Boot loader sources. |
| sys | Kernel sources. |
sys/arch/conf |
Kernel configuration files. GENERIC is the configuration used in release builds. NOTES contains documentation of all possible entries. |
| tests | Regression tests which can be run by Kyua. See tests/README for additional information. |
| tools | Utilities for regression testing and miscellaneous tasks. |
| usr.bin | User commands. |
| usr.sbin | System administration commands. |
For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see FreeBSD Handbook.