SPI_SYNC_LOCKED(9) Serial Peripheral Interface (S SPI_SYNC_LOCKED(9)NAME
spi_sync_locked - version of spi_sync with exclusive bus usage
int spi_sync_locked(struct spi_device * spi, struct spi_message * message);
device with which data will be exchanged
describes the data transfers
This call may only be used from a context that may sleep. The sleep is non-interruptible, and has no timeout. Low-overhead controller
drivers may DMA directly into and out of the message buffers.
This call should be used by drivers that require exclusive access to the SPI bus. It has to be preceded by a spi_bus_lock call. The SPI bus
must be released by a spi_bus_unlock call when the exclusive access is over.
It returns zero on success, else a negative error code.
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 SPI_SYNC_LOCKED(9)
Check Out this Related Man Page
SPI_ASYNC(9) Serial Peripheral Interface (S SPI_ASYNC(9)NAME
spi_async - asynchronous SPI transfer
int spi_async(struct spi_device * spi, struct spi_message * message);
device with which data will be exchanged
describes the data transfers, including completion callback
any (irqs may be blocked, etc)
This call may be used in_irq and other contexts which can't sleep, as well as from task contexts which can sleep.
The completion callback is invoked in a context which can't sleep. Before that invocation, the value of message->status is undefined. When
the callback is issued, message->status holds either zero (to indicate complete success) or a negative error code. After that callback
returns, the driver which issued the transfer request may deallocate the associated memory; it's no longer in use by any SPI core or
controller driver code.
Note that although all messages to a spi_device are handled in FIFO order, messages may go to different devices in other orders. Some
device might be higher priority, or have various "hard" access time requirements, for example.
On detection of any fault during the transfer, processing of the entire message is aborted, and the device is deselected. Until returning
from the associated message completion callback, no other spi_message queued to that device will be processed. (This rule applies equally
to all the synchronous transfer calls, which are wrappers around this core asynchronous primitive.)
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 SPI_ASYNC(9)
I know the following questions are noobish questions but I am asking them because I am confused about the basics of history behind UNIX and LINUX.
Ok onto business, my questions are-:
Was/Is UNIX ever an open source operating system ?
If UNIX was... (21 Replies)
Hello and thanks in advance for any help anyone can offer me
I'm trying to learn the find command and thought I was understanding it... Apparently I was wrong. I was doing compound searches and I started getting weird results with the -size test. I was trying to do a search on a 1G file owned by... (14 Replies)
i have installed quota on my centos 7 machine and its what im after (setting size limit on users, so they cant fill the hard drive)
i want to now make this part of my create user script for my sftp server so i want to do a echo and a read command so i capture the limit they enter... (0 Replies)
I need to write a shell script which opens a file and increments the version(text) within the file every time the script runs. For example:
$ cat docker_file.yml
So, I would like... (6 Replies)
We use DB2 v10.5 and using DBArtisan tool
Can someone please guide how to convert digits to binary numbers using db2 feature.
Ex> for number 9 , binary should be 1001 ( 8+1)
Any help appreciated. Thanks (2 Replies)
how to using tar with exclude directory and compress it using tar.Z
i only know how to exclude dir only with this command below:
tar -cvf /varios/restore/test.tar -X excludefile.txt /jfma/test1/
how to compress it using 1 command?
Please use CODE tags as... (6 Replies)
Quite an obscure question I think.
We have a rebuild process for remote sites that allows us to PXE rebuild a till (actually a PC with a touch screen and various fancy bits) running CentOS. The current CentOS5 tills work just fine with a tar image restore and some personalisation. Sadly,... (4 Replies)
I had recently learnt a bit of Docker(which provides containerization process).
Here are some of my learning points from it.
Let us start first with very basic question:
What is Docker:
Docker is a platform for sysadmins and developers to DEPLOY, DEVELOP and RUN applications ... (7 Replies)
What is the point of this? Whenever I close my shell it appends to the history file without adding this. I have never seen it overwrite my history file.
# When the shell exits, append to the history file instead of overwriting it
shopt -s histappend (3 Replies)
Hello... And thanks in advance for any help anyone can offer me
I was trying to work out the differences between displaying modify, access, and change times with the 'ls' command. Everything seems in order when I look at files, but the access time on a directory doesn't seem to change when I... (4 Replies)
I am having an issue here with CentOS release 6.6 (Final) that shows all of the space used up, but I can't tell where the space went.
Seemingly I am using up 100%, according to
Filesystem Size Used Avail Use% Mounted on... (27 Replies)
I'm trying to use a bash script for a psych experiment that involves listening to sound files and responding. If I have something like the code below, how can I make sure that a key press is assigned to RESPONSE only after the second echo statement?
for i in 1 2 3; do
... (10 Replies)
After the success of the jq - tool for parsing and manipulating JSON-Data someone wrote a tool called yq, which aims to be the same for YAML, what jq is for JSON. Seems to work fine. I'll definitely give it a chance in future.
... (1 Reply)
I am very pleased to announce that Dave Munro (gull04) is joining the Moderation Team, after being a very valuable member of UNIX.com for 15+ years.
Dave is an IT Consultant with 30 years of experience this year, has worked in many of the industry vertical market segments and has... (6 Replies)