kernel.git/drivers/dma/at_hdmac.c, branch linux-3.2.y

dmaengine: at_hdmac: check that each sg data length is non-null

2012-10-10T02:30:53Z

commit c456797681db814f4f5b36909e8e94047bf53d9c upstream. Avoid the construction of a malformed DMA request sent to the DMA controller. Log message is for debug only because this condition is unlikely to append and may only trigger at driver development time. Signed-off-by: Nicolas Ferre Signed-off-by: Vinod Koul Signed-off-by: Ben Hutchings

dmaengine: at_hdmac: fix comment in atc_prep_slave_sg()

2012-10-10T02:30:52Z

commit c618a9be0e8c0f36baee2560860a0118a428fb26 upstream. s/dma_memcpy/slave_sg/ and it is sg length that we are talking about. Signed-off-by: Nicolas Ferre Signed-off-by: Vinod Koul Signed-off-by: Ben Hutchings

dmaengine: at_hdmac: remove clear-on-read in atc_dostart()

2012-05-11T12:14:34Z

commit ed8b0d67f33518a16c6b2450fe5ebebf180c2d04 upstream. This loop on EBCISR register was designed to clear IRQ sources before enabling a DMA channel. This register is clear-on-read so a race condition can appear if another channel is already active and has just finished its transfer. Removing this read on EBCISR is fixing the issue as there is no case where an IRQ could be pending: we already make sure that this register is drained at probe() time and during resume. Signed-off-by: Nicolas Ferre Signed-off-by: Vinod Koul Signed-off-by: Ben Hutchings

at_hdmac: bugfix for enabling channel irq

2012-02-13T19:16:54Z

commit bda3a47c886664e86ee14eb79e9072b9e341f575 upstream. commit 463894705e4089d0ff69e7d877312d496ac70e5b deleted redundant chan_id and chancnt initialization in dma drivers as this is done in dma_async_device_register(). However, atc_enable_irq() relied on chan_id set before registering the device, what left only channel 0 functional for this driver. This patch introduces atc_enable/disable_chan_irq() as a variant of atc_enable/disable_irq() with the channel as explicit argument. Signed-off-by: Nikolaus Voss Signed-off-by: Nicolas Ferre Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman

dmaengine: delete redundant chan_id and chancnt initialization in dma drivers

2011-09-20T06:21:33Z

dma_async_device_register will re-init chan_id and chancnt, so whatever chan_id and chancnt are set in drivers, they will be re-written by dma_async_device_register. Cc: Nicolas Ferre Cc: Viresh Kumar Cc: Vinod Koul Cc: Piotr Ziecik Cc: Yong Wang Cc: Jaswinder Singh Cc: Pelagicore AB Signed-off-by: Barry Song Acked-by: Viresh Kumar Signed-off-by: Vinod Koul

dmaengine: at_hdmac: fix way to specify cyclic capability

2011-08-19T13:10:04Z

In this driver, we can trigger cyclic transfer on peripherals-DMA interfaces. It is dependent on driver implementation but cannot depend on a platform property: we remove the dma_has_cap(DMA_CYCLIC, ) test which has no meaning. Signed-off-by: Nicolas Ferre Signed-off-by: Vinod Koul

dmaengine: at_hdmac: add wrappers for testing channel state

2011-08-19T13:09:59Z

Cyclic property and paused state are encoded as bits in the channel status bitfield. Tests of those bits are wrapped in convenient helper functions. Signed-off-by: Nicolas Ferre Signed-off-by: Vinod Koul

dmaengine: at_hdmac: improve power management routines

2011-08-19T13:09:54Z

Save/restore dma controller state across a suspend-resume sequence. The prepare() function will wait for the non-cyclic channels to become idle. It also deals with cyclic operations with the start at next period while resuming. Signed-off-by: Nicolas Ferre Signed-off-by: Uwe Kleine-König Signed-off-by: Vinod Koul

dmaengine: at_hdmac: replace spin_lock* with irqsave variants

2011-08-19T13:09:48Z

dmaengine routines can be called from interrupt context and with interrupts disabled. Whereas spin_unlock_bh can't be called from such contexts. So this patch converts all spin_lock* routines to irqsave variants. Also, spin_lock() used in tasklet is converted to irqsave variants, as tasklet can be interrupted, and dma requests from such interruptions may also call spin_lock. Idea from dw_dmac patch by Viresh Kumar. Signed-off-by: Nicolas Ferre Signed-off-by: Uwe Kleine-König Signed-off-by: Vinod Koul

dma: at_hdmac.c: use resource_size

2011-06-06T08:13:59Z

Signed-off-by: H Hartley Sweeten Cc: Dan Williams Cc: Vinod Koul Signed-off-by: Vinod Koul