Commit Graph

16 Commits

Author SHA1 Message Date
Daniel Mack
13bbfb5c4e dma: cppi41: handle 0-length packets
When a 0-length packet is received on the bus, desc->pd0 yields 1,
which confuses the driver's users. This information is clearly wrong
and not in accordance to the datasheet, but it's been observed on an
AM335x board, very reproducible.

Fix this by looking at bit 19 in PD2 of the completed packet. This bit
will tell us if a zero-length packet was received on a queue. If it's
set, ignore the value in PD0 and report a total length of 0 instead.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-07-01 12:15:48 +05:30
George Cherian
975faaeb99 dma: cppi41: start tear down only if channel is busy
Start the channel tear down only if the channel is busy, else just
bail out. In some cases its seen that by the time the tear down is
initiated the cppi completes the DMA, especially in ISOCH transfers.

Signed-off-by: George Cherian <george.cherian@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-03-11 16:22:43 +05:30
Julia Lawall
f3b77727e8 drivers/dma: fix error return code
Set the return variable to an error code as done elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}

// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-01-20 14:58:03 +05:30
Sebastian Andrzej Siewior
cbf1e56e6a dma: cppi41: return code > 0 of pm_runtime_get_sync() is not an error
Return code of pm_runtime_get_sync() > 0 is not an error and may happen.
Noticed during rmmod & modprobe testing.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-11-12 14:28:25 +05:30
Sebastian Andrzej Siewior
1e378a6d77 dma: cppi41: redo descriptor collection in abort case
Most of the logic here is try and error since what actually happens does
not match the trm or I miss read it.
My first assumption was that the queue on which the tear-down descriptor
completes (their own complete queue vs "active descriptor" complete
queue) depends on the transfer direction. This seems not to be true
because I manage to trigger
|  WARN_ON(c->desc_phys != desc_phys);
and the other few were fine means the tear-down descriptor was valid but
on different queue.

This patch changes the logic here to look on both queues for the
descriptor.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-11-12 14:28:24 +05:30
Daniel Mack
706ff628f0 dma: cppi41: use cppi41_pop_desc() where possible
Use cppi41_pop_desc() when appropriate instead of open-coding the same
functionality again. That makes the code more readable. The function has
to be moved some lines up for this change.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-11-12 14:28:24 +05:30
Daniel Mack
f8964968ab dma: cppi41: restore more registers
With active users over suspend/resume cycles, it turns out that
more registers, in particular DMA_TDFDQ and RXHPCRA0, have to be
restored on resume.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-11-12 14:28:24 +05:30
Vinod Koul
ed83c0c8c1 dmaengine: cppi41: use DMA_COMPLETE for dma completion status
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-10-25 11:15:57 +05:30
Daniel Mack
f97b98d6d0 dma: cppi41: add support for suspend and resume
This patch adds support for suspend/resume functionality to the cppi41
DMA driver. The steps necessary to make the system resume properly were
figured out by trial-and-error. The code as it stands now is the
minimum that has to be done to put the musb host system on an AM33xx
system into an operable state after resume.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-10-07 07:41:39 +05:30
Daniel Mack
717d818169 dma: cppi41: add shortcut to &pdev->dev in cppi41_dma_probe()
Makes the code more readable and compact. No functional change.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-10-07 07:41:39 +05:30
Daniel Mack
b46ce4d01e dma: cppi41: s/deinit_cpii41/deinit_cppi41/
Fix a misspelled function name.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-10-07 07:41:39 +05:30
Daniel Mack
e327e21fb2 dma: cppi41: pass around device instead of platform_device
Instead of passing around struct plafform_device, use struct device and
save one level of dereferencing. This affects the following functions:

 * cppi41_add_chans
 * purge_descs
 * deinit_cpii41
 * init_descs
 * init_cppi41
 * cppi_glue_infos

It's just a cosmetic cleanup that makes the code more readable.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-10-07 07:41:39 +05:30
Dan Carpenter
2d17f7fb69 dma: cppi41: off by one in desc_to_chan()
The test here should be ">=" instead of ">".  The cdd->chan_busy[] array
has "ALLOC_DECS_NUM" elements.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-28 15:46:33 -07:00
Sebastian Andrzej Siewior
d6aafa2bf3 dma: cpp41: enable pm_runtime during init
With enabled pm_runtime in the kernel the device won't work because it
is not "on" during the probe function. This patch enables the device via
pm_runtime on probe so it remains activated.

Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2013-08-27 14:19:52 -05:00
Sebastian Andrzej Siewior
bd2fbf3a56 dma: cpp41: make it compile with CONFIG_BUG=n
Before Randy figures out that this does not compile with CONFIG_BUG=n
here is a fix for it.

Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2013-08-27 14:08:11 -05:00
Sebastian Andrzej Siewior
9b3452d1fa usb: musb dma: add cppi41 dma driver
This driver is currently used by musb' cppi41 couter part. I may merge
both dma engine user of musb at some point but not just yet.

The driver seems to work in RX/TX mode in host mode, tested on mass
storage. I increaed the size of the TX / RX transfers and waited for the
core code to cancel a transfers and it seems to recover.

v2..3:
- use mall transfers on RX side and check data toggle.
- use rndis mode on tx side so we haveon interrupt for 4096 transfers.
- remove custom "transferred" hack and use dmaengine_tx_status() to
  compute the total amount of data that has been transferred.
- cancel transfers and reclaim descriptors

v1..v2:
- RX path added
- dma mode 0 & 1 is working
- device tree nodes re-created.

Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <djbw@fb.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2013-08-09 17:40:16 +03:00