On Wed, Apr 24, 2013 at 03:24:27PM +0530, Laxman Dewangan wrote: > Implement suspend/resume callbacks to store APB DMA channel's > register on suspend and restore APB DMA channel's register on > resume. > > Signed-off-by: Laxman Dewangan <ldewangan@xxxxxxxxxx> > --- > drivers/dma/tegra20-apb-dma.c | 65 +++++++++++++++++++++++++++++++++++++++++ > 1 files changed, 65 insertions(+), 0 deletions(-) > > diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c > index 5a0b66c..ce19340 100644 > --- a/drivers/dma/tegra20-apb-dma.c > +++ b/drivers/dma/tegra20-apb-dma.c > @@ -30,6 +30,7 @@ > #include <linux/of.h> > #include <linux/of_device.h> > #include <linux/platform_device.h> > +#include <linux/pm.h> > #include <linux/pm_runtime.h> > #include <linux/slab.h> > #include <linux/clk/tegra.h> > @@ -199,6 +200,7 @@ struct tegra_dma_channel { > > /* Channel-slave specific configuration */ > struct dma_slave_config dma_sconfig; > + struct tegra_dma_channel_regs channel_reg; > }; > > /* tegra_dma: Tegra DMA specific information */ > @@ -1440,11 +1442,74 @@ static int tegra_dma_runtime_resume(struct device *dev) > return 0; > } > > +#ifdef CONFIG_PM_SLEEP > +static int tegra_dma_pm_suspend(struct device *dev) > +{ > + struct tegra_dma *tdma = dev_get_drvdata(dev); > + int i; > + int ret; > + > + /* Enable clock before accessing register */ > + ret = tegra_dma_runtime_resume(dev); > + if (ret < 0) > + return ret; You dont seem to handle suspend when DMA is active? Otherwise looks fine. Stephen, you okay with this patch? -- ~Vinod > + > + tdma->reg_gen = tdma_read(tdma, TEGRA_APBDMA_GENERAL); > + for (i = 0; i < tdma->chip_data->nr_channels; i++) { > + struct tegra_dma_channel *tdc = &tdma->channels[i]; > + struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg; > + > + 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); > + ch_reg->ahb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBSEQ); > + ch_reg->apb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBSEQ); > + } > + > + /* Disable clock */ > + tegra_dma_runtime_suspend(dev); > + return 0; > +} > + > +static int tegra_dma_pm_resume(struct device *dev) > +{ > + struct tegra_dma *tdma = dev_get_drvdata(dev); > + int i; > + int ret; > + > + /* Enable clock before accessing register */ > + ret = tegra_dma_runtime_resume(dev); > + if (ret < 0) > + return ret; > + > + tdma_write(tdma, TEGRA_APBDMA_GENERAL, tdma->reg_gen); > + tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0); > + tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul); > + > + for (i = 0; i < tdma->chip_data->nr_channels; i++) { > + struct tegra_dma_channel *tdc = &tdma->channels[i]; > + struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg; > + > + tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_reg->apb_seq); > + tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_reg->apb_ptr); > + tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_reg->ahb_seq); > + tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_reg->ahb_ptr); > + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, > + (ch_reg->csr & ~TEGRA_APBDMA_CSR_ENB)); > + } > + > + /* Disable clock */ > + tegra_dma_runtime_suspend(dev); > + return 0; > +} > +#endif > static const struct dev_pm_ops tegra_dma_dev_pm_ops = { > #ifdef CONFIG_PM_RUNTIME > .runtime_suspend = tegra_dma_runtime_suspend, > .runtime_resume = tegra_dma_runtime_resume, > #endif > + SET_SYSTEM_SLEEP_PM_OPS(tegra_dma_pm_suspend, tegra_dma_pm_resume) > }; > > static struct platform_driver tegra_dmac_driver = { > -- > 1.7.1.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html