Commit Graph

3 Commits

Author SHA1 Message Date
Sinan Kaya 793ae66c7d dmaengine: qcom_hidma: add error reporting for tx_status
The HIDMA driver is capable of error detection. However, the error was
not being passed back to the client when tx_status API is called.

Changing the error handling behavior to follow this oder.

1. dmaengine asserts error interrupt
2. Driver receives and mark's the txn as error
3. Driver completes the txn and intimates the client. No further
   submissions. Drop the locks before calling callback, as subsequent
   processing by client maybe in callback thread.
4. Client invokes status and you can return error
5. On error, client calls terminate_all. You can reset channel, free all
   descriptors in the active, pending and completed lists
6. Client prepares new txn and so on.

As part of this work, got rid of the reset in the interrupt handler when
an error happens and the HW is put into disabled state. The only way to
recover is for the client to terminate the channel.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-08-31 21:27:32 +05:30
Vinod Koul 4cad91b2a9 dmaengine: qcom_hidma_lli: kill the tasklets upon exit
drivers should ensure that tasklets are killed, so that they can't be
run after driver remove is executed

Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Cc: Sinan Kaya <okaya@codeaurora.org>
2016-07-23 16:07:27 +05:30
Sinan Kaya d1615ca2e0 dmaengine: qcom_hidma: implement lower level hardware interface
This patch implements the hardware hooks for the HIDMA channel driver.

The main functions of interest are:
- hidma_ll_init
- hidma_ll_request
- hidma_ll_queue_request
- hidma_ll_hw_start

OS layer calls the hidma_ll_init function during probe to set up the
hardware. At this moment, the number of supported descriptors are also
given. On each request, a descriptor is allocated from the free pool and
filled in with the transfer parameters. Multiple requests can be queued
into the hardware via the OS interface. When client is ready for requests
to be executed, start method is called.

Completions are delivered via callbacks via tasklet.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-05-14 11:54:45 +05:30