diff options
| author | Laxman Dewangan <ldewangan@nvidia.com> | 2012-07-20 12:01:08 +0400 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@linux.intel.com> | 2012-07-31 14:45:05 +0400 |
| commit | fed57cd375ece6d271e45d9ad630c7de632e74b6 (patch) | |
| tree | c75b89c7a25935a52b06c15843678813af2803d2 | |
| parent | dbde5c2934d10f87cc45ed9a9b95cac6f0c0fdd2 (diff) | |
| download | linux-fed57cd375ece6d271e45d9ad630c7de632e74b6.tar.xz | |
dma: tegra: enable/disable dma clock
Enable the DMA clock when allocating channel and
disable clock when freeing channels.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
| -rw-r--r-- | drivers/dma/tegra20-apb-dma.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index d52dbc6c54ab..24acd711e032 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -1119,15 +1119,21 @@ struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic( static int tegra_dma_alloc_chan_resources(struct dma_chan *dc) { struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma *tdma = tdc->tdma; + int ret; dma_cookie_init(&tdc->dma_chan); tdc->config_init = false; - return 0; + ret = clk_prepare_enable(tdma->dma_clk); + if (ret < 0) + dev_err(tdc2dev(tdc), "clk_prepare_enable failed: %d\n", ret); + return ret; } static void tegra_dma_free_chan_resources(struct dma_chan *dc) { struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma *tdma = tdc->tdma; struct tegra_dma_desc *dma_desc; struct tegra_dma_sg_req *sg_req; @@ -1163,6 +1169,7 @@ static void tegra_dma_free_chan_resources(struct dma_chan *dc) list_del(&sg_req->node); kfree(sg_req); } + clk_disable_unprepare(tdma->dma_clk); } /* Tegra20 specific DMA controller information */ @@ -1255,6 +1262,13 @@ static int __devinit tegra_dma_probe(struct platform_device *pdev) } } + /* Enable clock before accessing registers */ + ret = clk_prepare_enable(tdma->dma_clk); + if (ret < 0) { + dev_err(&pdev->dev, "clk_prepare_enable failed: %d\n", ret); + goto err_pm_disable; + } + /* Reset DMA controller */ tegra_periph_reset_assert(tdma->dma_clk); udelay(2); @@ -1265,6 +1279,8 @@ static int __devinit tegra_dma_probe(struct platform_device *pdev) tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0); tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul); + clk_disable_unprepare(tdma->dma_clk); + INIT_LIST_HEAD(&tdma->dma_dev.channels); for (i = 0; i < cdata->nr_channels; i++) { struct tegra_dma_channel *tdc = &tdma->channels[i]; |