Hello Xiang Xiao,
Can you connect me with Donny or can you help me to understand spi_slave
semaphore "unlock" ?
Looking into spi_slave_driver.c:330
while (priv->rx_length == 0)
{
remaining_words = SPIS_CTRLR_QPOLL(priv->ctrlr);
if (remaining_words == 0)
{
spiinfo("All words retrieved!\n");
}
else
{
spiinfo("%zu words left in the buffer\n", remaining_words);
}
if (priv->rx_length == 0)
{
nxmutex_unlock(&priv->lock);
if (filep->f_oflags & O_NONBLOCK)
{
return -EAGAIN;
}
ret = nxsem_wait(&priv->wait);
if (ret < 0)
{
return ret;
}
ret = nxmutex_lock(&priv->lock);
if (ret < 0)
{
spierr("Failed to get exclusive access: %d\n", ret);
return ret;
}
}
}
we have:
ret = nxsem_wait(&priv->wait);
I think read operation will be locked until the function spi_slave_notify
has been called, but I cannot find any call of SPIS_DEV_NOTIFY in nuttx
repo. Did you have different implementation in your side ?
Em ter., 15 de out. de 2024 às 12:28, Felipe Moura Oliveira <
moura....@gmail.com> escreveu:
> Hello All,
>
> I did a dummy question, in master branch, spi slave implementation already
> blocked until new data is available. I wasn't working in the master branch
> but I will switch to.
>
> Em ter., 15 de out. de 2024 às 11:45, Felipe Moura Oliveira <
> moura....@gmail.com> escreveu:
>
>> Hello Xiang Xiao,
>>
>> thanks for sharing with me about rpmsg, to be honest it is new for me =/,
>> I was locked in baremetal for several years. For now I cannot use it
>> because my host mcu is running baremetal (maybe in the future we will
>> change it). I developed a simple protocol using ack and nak whey to handle
>> communication with master and slave. About "lock" my app until data is
>> available, I am thinking use semaphore to wait to do it, so my solution
>> will be able to sleep my mcu until spi releases it.
>>
>> Em ter., 15 de out. de 2024 às 11:24, Xiang Xiao <
>> xiaoxiang781...@gmail.com> escreveu:
>>
>>> Yes, we use DMA for both SPI master/slave, but DMA is more related to the
>>> driver not the framework.
>>>
>>> On Tue, Oct 15, 2024 at 2:08 PM Tomek CEDRO <to...@cedro.info> wrote:
>>>
>>> > One question by the way someone asked me recently - can NuttX SPI Slave
>>> > work in DMA mode? :-)
>>> >
>>> > --
>>> > CeDeROM, SQ7MHZ, http://www.tomek.cedro.info
>>> >
>>>
>>
>>
>> --
>> *Felipe Moura de Oliveira*
>> *Universidade Federal de Minas Gerais*
>> Linkedin <https://www.linkedin.com/in/felipe-oliveira-75a651a0>
>> <https://twitter.com/FelipeMOliveir?lang=pt-br>
>>
>
>
> --
> *Felipe Moura de Oliveira*
> *Universidade Federal de Minas Gerais*
> Linkedin <https://www.linkedin.com/in/felipe-oliveira-75a651a0>
> <https://twitter.com/FelipeMOliveir?lang=pt-br>
>
--
*Felipe Moura de Oliveira*
*Universidade Federal de Minas Gerais*
Linkedin <https://www.linkedin.com/in/felipe-oliveira-75a651a0>
<https://twitter.com/FelipeMOliveir?lang=pt-br>
