lwn.git/arch/arm/mach-tegra/dma.c, branch docs-fixes

ARM: tegra: dma: remove legacy APB DMA driver

2012-09-17T15:34:02+00:00

Remove the legacy APB dma driver. The APB DMA support is moved to dmaengine based Tegra APB DMA driver. All clients are also moved to dmaengine based APB DMA driver. Signed-off-by: Laxman Dewangan Signed-off-by: Stephen Warren

ARM: tegra: dma: rename driver name for clock to "tegra-apbdma"

2012-06-26T19:04:58+00:00

Rename the driver name of the clock entry of Tegra APBDMA to tegra-apbdma from of tegra-dma. This name is more aligned towards the movement of dmaengine based new DMA driver. Signed-off-by: Laxman Dewangan Signed-off-by: Stephen Warren

ARM: tegra: add clk_prepare/clk_unprepare

2012-06-11T17:53:29+00:00

Use clk_prepare/clk_unprepare as required by the generic clk framework. Tested on Ventana and Cardhu. Signed-off-by: Prashant Gaikwad Signed-off-by: Stephen Warren

ARM: tegra: dma: not required to move requestor when stopping.

2012-02-07T02:25:01+00:00

It is not require to move the requestor of dma to INVALID option before stopping dma. Signed-off-by: Laxman Dewangan Acked-by: Stephen Warren Tested-by: Stephen Warren Signed-off-by: Olof Johansson

ARM: tegra: Pause DMA when reading transfer count

2012-02-07T02:24:59+00:00

In order to read an accurate channel transfer count from the APB DMA engine, the DMA controller must be paused first. Signed-off-by: Laxman Dewangan Acked-by: Stephen Warren Tested-by: Stephen Warren Signed-off-by: Olof Johansson

ARM: tegra: use APB DMA for accessing APB devices

2012-02-07T02:24:58+00:00

Tegra2 hangs if APB registers are accessed from the cpu during an apb dma operation. The workaround is to use apb dma to read/write the registers instead. There is a dependency loop between fuses, clocks, and APBDMA. If dma is enabled, fuse reads must go through APBDMA to avoid corruption due to a hw bug. APBDMA requires a clock to be enabled. Clocks must read a fuse to determine allowable cpu frequencies. Separate out the fuse DMA initialization, and allow the fuse read and write functions to be called without using DMA before the DMA initialization has been completed. Access to the fuses before APBDMA is initialized won't hit the hardware bug because nothing else can be using DMA. Original fuse registar access code from Varun Wadekar , improved by Colin Cross and later moved to separate driver by Jon Mayo . Major refactoring/cleanup by Olof Johansson . Changes since v1: * fix 'return false' on error condition * dequeue dma ops in case of timeout From: Jon Mayo . Signed-off-by: Jon Mayo . Signed-off-by: Olof Johansson Acked-by: Stephen Warren

ARM: tegra: Don't WARN_ON() for too early dma channel allocations

2012-02-07T02:24:58+00:00

Since we'll do opportunistic allocations before the dma subsystem is enabled we want just silent failures and retries instead. Signed-off-by: Olof Johansson

ARM: tegra: dma: staticify some tables and functions

2011-10-13T21:08:29+00:00

None of them are used externally. Signed-off-by: Olof Johansson Acked-by: Stephen Warren Acked-by: Arnd Bergmann

Fix common misspellings

2011-03-31T14:26:23+00:00

Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi

ARM: Tegra: DMA: Fail safe if initialization fails

2011-02-23T22:06:03+00:00

tegra_dma_init currently simply bails out early if any initialization fails. This skips various data-structure initialization. In turn, this means that tegra_dma_allocate_channel can still hand out channels. In this case, when tegra_dma_free_channel is called, which calls tegra_dma_cancel, the walking on ch->list will OOPS since the list's next/prev pointers may still be NULL. To solve this, add an explicit "initialized" flag, only set this once _init has fully completed successfully, and have _allocate_channel refuse to hand out channels if this is not set. While at it, simplify _init: * Remove redundant memsets * Use bitmap_fill to mark all channels as in-use up-front, and remove some now-redundant bitmap initialization loops. * Only mark a channel as free once all channel-related initialization has completed. Finally, the successful exit path from _init always has ret==0, so just hard-code that return. The error path still returns ret. Signed-off-by: Stephen Warren Signed-off-by: Colin Cross