From 4aad5be04088d9b6c2783d5f0fb6b1ac7bbc45c1 Mon Sep 17 00:00:00 2001 From: Jon Hunter Date: Fri, 13 Nov 2015 16:39:41 +0000 Subject: [PATCH] dmaengine: tegra-apb: Only save channel state for those in use Currently the tegra-apb DMA driver suspend/resume helpers, save and restore the registers for all channels regardless of whether they are in use or not. Change this so that only channels that have been allocated and configured are saved and restored. Signed-off-by: Jon Hunter Signed-off-by: Vinod Koul --- drivers/dma/tegra20-apb-dma.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index 18a561376c63..d4cabd6931e5 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -1545,6 +1545,10 @@ static int tegra_dma_pm_suspend(struct device *dev) struct tegra_dma_channel *tdc = &tdma->channels[i]; struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg; + /* Only save the state of DMA channels that are in use */ + if (!tdc->config_init) + continue; + ch_reg->csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR); ch_reg->ahb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBPTR); ch_reg->apb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBPTR); @@ -1579,6 +1583,10 @@ static int tegra_dma_pm_resume(struct device *dev) struct tegra_dma_channel *tdc = &tdma->channels[i]; struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg; + /* Only restore the state of DMA channels that are in use */ + if (!tdc->config_init) + continue; + if (tdma->chip_data->support_separate_wcount_reg) tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, ch_reg->wcount); -- 2.45.2