The variable is dereferenced without first checking if it's null, leading
to the following warning: 'Variable dereferenced before check: desc.'

     drivers/dma/amd/ptdma/ptdma-dmaengine.c: pt_cmd_callback_work()
     warn: variable dereferenced before check 'desc'

Therefore, move the condition check for the 'desc' variable to the first
place and remove the redundant extra condition check.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/bfa0a979-ce9f-422d-92c3-34921155d048@stanley.mountain/
Fixes: 656543989457 ("dmaengine: ptdma: Utilize the AE4DMA engine's multi-queue functionality")
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Link: https://lore.kernel.org/r/20250421114215.1687073-1-Basavaraj.Natikar@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

As AE4DMA offers multi-channel functionality compared to PTDMA’s single
queue, utilize multi-queue, which supports higher speeds than PTDMA, to
achieve higher performance using the AE4DMA workqueue based mechanism.

Fixes: 69a47b16a51b ("dmaengine: ptdma: Extend ptdma to support multi-channel and version")
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Link: https://lore.kernel.org/r/20250203162511.911946-4-Basavaraj.Natikar@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Instead of using the defined maximum hardware queue, which can lead to
incorrect values if the counts mismatch, use the exact supported MSI
count and its corresponding IRQ number.

Fixes: 90a30e268d9b ("dmaengine: ae4dma: Add AMD ae4dma controller driver")
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Link: https://lore.kernel.org/r/20250203162511.911946-3-Basavaraj.Natikar@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Two previously used PCI IDs are deprecated and should not be used for
AE4DMA. Hence, remove as they are unsupported for AE4DMA.

Fixes: 90a30e268d9b ("dmaengine: ae4dma: Add AMD ae4dma controller driver")
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Link: https://lore.kernel.org/r/20250203162511.911946-2-Basavaraj.Natikar@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Don't populate the read-only arrays h2c_types and c2h_types on the
stack at run time, instead make them static const.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20240912131017.588141-1-colin.i.king@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

The get_dma_ops and set_dma_ops APIs were never for driver to use. Remove
these calls from QDMA driver. Instead, pass the DMA device pointer from the
qdma_platdata structure.

Fixes: 73d5fc92a11c ("dmaengine: amd: qdma: Add AMD QDMA driver")
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240918181022.2155715-1-lizhi.hou@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Use the ptdma_debugfs_setup function to register debugfs for AE4DMA DMA
engine.

Reviewed-by: Raju Rangoju <Raju.Rangoju@amd.com>
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Link: https://lore.kernel.org/r/20241025095931.726018-7-Basavaraj.Natikar@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

To support multi-channel functionality with AE4DMA engine, extend the
ptdma-debugfs with reusable components.

Reviewed-by: Raju Rangoju <Raju.Rangoju@amd.com>
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Link: https://lore.kernel.org/r/20241025095931.726018-6-Basavaraj.Natikar@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Use the pt_dmaengine_register function to register a AE4DMA DMA engine.

Reviewed-by: Raju Rangoju <Raju.Rangoju@amd.com>
Reviewed-by: Philipp Stanner <pstanner@redhat.com>
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Link: https://lore.kernel.org/r/20241025095931.726018-5-Basavaraj.Natikar@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>