diff options
| author | Laxman Dewangan <ldewangan@nvidia.com> | 2013-04-24 15:24:27 +0530 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@intel.com> | 2013-05-02 22:19:20 +0530 |
| commit | 3065c194670b61e213656ce25976d7c8a95e3c93 (patch) | |
| tree | f2d9b86bbe35623d9885f517f38c965f569675af /drivers/dma | |
| parent | b2396f7984ea09e83d489cfca6d5da62cc22945a (diff) | |
dma: tegra: implement suspend/resume callbacks
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@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | 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 5a0b66c2a60..ce193409ebd 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; + + 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 = { |