There's no reason to require callers to cast their data to uint8_t *
when the data might e.g. originate in a packed struct or some other
data type. Instead, be nice to callers and let them use any pointer
they want. Additionally, declare the TX buffer as a const pointer so
unnecessary typecasts aren't needed for that either (if the data
originates in a const location).
Change-Id: I1482ca4e350b5a7fbda6871ed9f54f255af3aa9e
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
When configured at a frequency of 2MHz, a transaction writing
3 bytes and reading 1 byte fails silently (last byte cannot be
read back from the device). Enabling CONFIG_SPI_DEBUG fixes the
issue.
Scope traces show that the transaction (from /CS assert to /CS
deassert) takes 14us and there is activity on the MOSI line
after /CS is deasserted. A transaction writing 2 bytes and reading
3 bytes take 22us.
The issue is due to the fact that completed() deasserts /CS after
the driver has put 3 bytes in the TXFIFO and taken 1 byte from RXFIFO.
Just because the last byte made it to the TXFIFO, it doesn't mean that
it was put on the MOSI line.
The fix:
For a transaction sending T bytes and expecting R bytes, let N=max(T,R).
Send exactly N bytes and wait for exactly N bytes (or an error). This
way, we are sure that all the bytes were sent to the target device.
Also:
Stop calling pull_data() after every byte sent, it might take a while
for a byte to show up in RXFIFO.
If RFS bit is set, stop sending bytes (will be really useful with a
bigger RFT).
Flushing RXFIFO in spi_intel_transceive() is not needed anymore.
Change-Id: Ifb06a12b03e3e20d6ace4d9f3a20fc11ec3bb010
Signed-off-by: Vlad Lungu <vlad.lungu@windriver.com>
Looking at all structs as to where we can pack them a little better, and
calling out the padding/stride at the end for future expansion.
Change-Id: I4a651092e950dd3d915af9fa0ee0d7d59803e58f
Signed-off-by: Dan Kalowsky <daniel.kalowsky@intel.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Adds extern "C" { } blocks to header files so that they can be
safely used by C++ source files.
Change-Id: Ia4db0c36a5dac5d3de351184a297d2af0df64532
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
Johan Hedberg