tests: drivers: spi_loopback: Fix NULL rx buff testcase

[raffarost]

Fixes setup of TX buffer, which shouldn't be NULL in the RX NULL tescase.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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[nordic-piks]

@nordic-pikr FYI

[nordic-pikr]

@raffarost please have a look 89168

[raffarost]

@raffarost please have a look 89168

hi @nordic-pikr
Shouldn't the testcase be modified as well? Effectively we see a NULL pointer for both TX and RX inside the driver, which is a different condition (but should be managed by the driver, as you mentioned).

[nordic-pikr]

@raffarost please have a look 89168

hi @nordic-pikr Shouldn't the testcase be modified as well? Effectively we see a NULL pointer for both TX and RX inside the driver, which is a different condition (but should be managed by the driver, as you mentioned).

Ok, you're right. What would you say to adding another one test case, with spi_loopback_transceive(spec, NULL, NULL); ?

[raffarost]

@raffarost please have a look 89168

hi @nordic-pikr Shouldn't the testcase be modified as well? Effectively we see a NULL pointer for both TX and RX inside the driver, which is a different condition (but should be managed by the driver, as you mentioned).

Ok, you're right. What would you say to adding another one test case, with spi_loopback_transceive(spec, NULL, NULL); ?

When spi_context_buffers_setup() is called, this condition is converted into the test_nop_nil_bufs testcase (internal buffers are replaced by NULL), so I guess it is already covered by that one.

[nordic-pikr]

@raffarost please have a look 89168

hi @nordic-pikr Shouldn't the testcase be modified as well? Effectively we see a NULL pointer for both TX and RX inside the driver, which is a different condition (but should be managed by the driver, as you mentioned).

Ok, you're right. What would you say to adding another one test case, with spi_loopback_transceive(spec, NULL, NULL); ?

When spi_context_buffers_setup() is called, this condition is converted into the test_nop_nil_bufs testcase (internal buffers are replaced by NULL), so I guess it is already covered by that one.

Is it covered by test_nop_nil_bufs? In this case spi_transceive_dt will get two spi_buf_set type pointers and I propose pass NULL instead. It is not exactly the same, right? @tbursztyka, @teburd any opinion on that? Let's move this discussion to 90699 as is not related to this PR