linux-stable.git/drivers/dma/qcom, branch v4.13.2

dmaengine: qcom_hidma: correct API violation for submit

2017-07-03T05:09:51+00:00

Current code is violating the DMA Engine API by putting the submitted
requests directly into the HW queue. This causes queued transactions
to be started by another thread as soon as the first one finishes.

The DMA Engine document clearly states this.

"dmaengine_submit() will not start the DMA operation".

Move HW queuing of the requests into the issue_pending() routine
to comply with API requirements also create a new queued state for
temporarily holding the requests.

A descriptor goes through these transitions now.

free->prepared->queued->active->completed->free

as opposed to

free->prepared->active->completed->free

Signed-off-by: Sinan Kaya 
Signed-off-by: Vinod Koul

dmaengine: qcom_hidma: allow ACPI/DT parameters to be overridden

2017-06-26T02:57:39+00:00

Parameters like maximum read/write request size and the maximum
number of active transactions are currently configured in DT/ACPI.

This patch allows a user to override these to fine tune performance
for their application.

Signed-off-by: Sinan Kaya 
Signed-off-by: Vinod Koul

dmaengine: qcom_hidma: pause the channel on shutdown

2017-03-27T05:13:38+00:00

We need to ensure that all DMAs and interrupts are cleared during
shutdown operation in order for kexec to start the next kernel clearly.

Otherwise, HW could be performing a DMA into random addresses in the
middle of second kernel start.

Signed-off-by: Sinan Kaya 
Signed-off-by: Vinod Koul

dmaengine: qcom_hidma: disable/enable IRQs on pause/resume

2017-03-27T05:13:38+00:00

Once the channels are stopped, disable interrupts to make sure no new
HW interaction can happen.

Similarly, re-enable the interrupts only if we know that channel is
operational again.

Signed-off-by: Sinan Kaya 
Signed-off-by: Vinod Koul

dmaengine: qcom_hidma: autoload while probing ACPI

2016-11-23T04:17:32+00:00

MODULE_DEVICE_TABLE is used by the kernel to determine which device driver
should be loaded for which platform device. MODULE_DEVICE_TABLE has been
only defined for the device-tree based platforms in the current code.
Defining it also for ACPI based platforms.

Signed-off-by: Sinan Kaya 
Signed-off-by: Vinod Koul

dmaengine: qcom_hidma: cleanup sysfs entries during remove

2016-11-15T03:28:12+00:00

The 4.8-rc8 kernel is printing duplicate file entry warnings while removing
the HIDMA object. This is caused by stale sysfs entries remaining from the
previous execution.

_sysfs_warn_dup+0x5c/0x78
 sysfs_add_file_mode_ns+0x13c/0x1c0
 sysfs_create_file_ns+0x2c/0x40
 device_create_file+0x54/0xa0
 hidma_probe+0x7c8/0x808

Create hidma_sysfs_init and hidma_sysfs_uninit functions and call them from
the probe and remove path. To do proper clean up, adding the attrs object
to the device data structure to keep it around until remove call is made.

Signed-off-by: Sinan Kaya 
Signed-off-by: Vinod Koul

dmaengine: qcom_hidma: hide MSI handler when unused

2016-11-14T05:23:52+00:00

The newly added MSI support causes a harmless warning when MSI
is disabled:

drivers/dma/qcom/hidma.c:558:20: error: 'hidma_chirq_handler_msi' defined but not used [-Werror=unused-function]

This adds another #ifdef to match that around the users of the function.

Fixes: 1c0e3e82a7fb ("dmaengine: qcom_hidma: add MSI support for interrupts")
Signed-off-by: Arnd Bergmann 
Acked-by: Sinan Kaya 
Signed-off-by: Vinod Koul

dmaengine: qcom_hidma: remove unneeded of_node_put()

2016-11-14T03:38:32+00:00

Device node iterators put the previous value of the index variable, so an
explicit put causes a double put.

Generated by: scripts/coccinelle/iterators/device_node_continue.cocci

Signed-off-by: Wei Yongjun 
Signed-off-by: Vinod Koul

dmaengine: qcom_hidma: add MSI support for interrupts

2016-11-03T13:25:45+00:00

The interrupts can now be delivered as platform MSI interrupts on newer
platforms. The code looks for a new OF and ACPI strings in order to enable
the functionality.

Signed-off-by: Sinan Kaya 
Signed-off-by: Vinod Koul

dmaengine: qcom_hidma: protect common data structures

2016-11-03T13:25:45+00:00

When MSI interrupts are supported, error and the transfer interrupt can
come from multiple processor contexts.

Each error interrupt is an MSI interrupt. If the channel is disabled by
the first error interrupt, the remaining error interrupts will gracefully
return in the interrupt handler.

If an error is observed while servicing the completions in success case,
the posting of the completions will be aborted as soon as channel disabled
state is observed. The error interrupt handler will take it from there and
finish the remaining completions. We don't want to create multiple success
and error messages to be delivered to the client in mixed order.

Signed-off-by: Sinan Kaya 
Signed-off-by: Vinod Koul