STM32: fix incorrect burst length in drivers' DMA configurations #100105
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The burst length unit is bytes, not number of transfers. This had not been an issue since the DMA driver historically ignored the values, but has now become one since they are used and (most importantly for us) validated. Fixes broken 16-bit on STM32N6 series. Signed-off-by: Mathieu Choplain <mathieu.choplain-ext@st.com>
The burst length unit is bytes, not number of transfers. This had not been an issue since the DMA driver historically ignored the values, but has now become one since they are used and (most importantly for us) validated. Signed-off-by: Mathieu Choplain <mathieu.choplain-ext@st.com>
The burst length unit is bytes, not number of transfers. This had not been an issue since the DMA driver historically ignored the values, but has now become one since they are used and (most importantly for us) validated. Signed-off-by: Mathieu Choplain <mathieu.choplain-ext@st.com>
The burst length unit is bytes, not number of transfers. This had not been an issue since the DMA driver historically ignored the values, but has now become one since they are used and (most importantly for us) validated. Signed-off-by: Mathieu Choplain <mathieu.choplain-ext@st.com>
The burst length unit is bytes, not number of transfers. This had not been an issue since the DMA driver historically ignored the values, but has now become one since they are used and (most importantly for us) validated. Signed-off-by: Mathieu Choplain <mathieu.choplain-ext@st.com>
The burst length unit is bytes, not number of transfers. This had not been an issue since the DMA driver historically ignored the values, but has now become one since they are used and (most importantly for us) validated. Signed-off-by: Mathieu Choplain <mathieu.choplain-ext@st.com>
The burst length unit is bytes, not number of transfers. This had not been an issue since the DMA driver historically ignored the values, but has now become one since they are used and (most importantly for us) validated. Signed-off-by: Mathieu Choplain <mathieu.choplain-ext@st.com>
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The burst length unit is bytes, not number of transfers. This had not been an issue since the DMA driver historically ignored the values, but has now become one since they are used and (most importantly for us) validated. Signed-off-by: Mathieu Choplain <mathieu.choplain-ext@st.com>
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Since #99258, the
{source,dest}_burst_lengthargument is no longer ignored by thedma_stm32u5driver (notably used on STM32N6 series). Many drivers were mistakenly setting its value to 1 under the assumption that the unit was number of data-sized transfers, which is WRONG - the parameter's unit is in bytes.This means that most configurations were wrong unless byte-sized transfers were used.
Fix all drivers by setting a proper value for the
burst_lengthparameters, equal to the data size (i.e., resulting in one transfer, as originally intended).Fixes #100100.
cc @avolmat-st for video driver, @gautierg-st for ADC, ...