On 06/06/17 10:51, Mikko Perttunen wrote:
> On 06.06.2017 11:59, Jon Hunter wrote:
>> Commit edd3bdbe9db1 ("dmaengine: tegra-apb: Correct runtime-pm usage")
>> added pm_runtime_get/put() calls to the tegra-apb DMA system suspend
>> callbacks. Runtime PM is disabled during system suspend and so these
>> APIs cannot be used. Fix the suspend handling for the tegra-apb DMA by
>> moving the save and restore of the DMA register context into the
>> runtime PM suspend and resume callbacks, and then use the
>> pm_runtime_force_suspend/resume() APIs to invoke the runtime PM
>> callbacks during system suspend.
>>
>> Fixes: edd3bdbe9db1 ("dmaengine: tegra-apb: Correct runtime-pm usage")
>>
>> Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx>
>> ---
>> drivers/dma/tegra20-apb-dma.c | 57
>> +++++++++++++++----------------------------
>> 1 file changed, 19 insertions(+), 38 deletions(-)
>>
>> diff --git a/drivers/dma/tegra20-apb-dma.c
>> b/drivers/dma/tegra20-apb-dma.c
>> index 3722b9d8d9fe..5c3ddd61dc3b 100644
>> --- a/drivers/dma/tegra20-apb-dma.c
>> +++ b/drivers/dma/tegra20-apb-dma.c
>> @@ -1494,35 +1494,7 @@ static int tegra_dma_remove(struct
>> platform_device *pdev)
>> static int tegra_dma_runtime_suspend(struct device *dev)
>> {
>> struct tegra_dma *tdma = dev_get_drvdata(dev);
>> -
>> - clk_disable_unprepare(tdma->dma_clk);
>> - return 0;
>> -}
>> -
>> -static int tegra_dma_runtime_resume(struct device *dev)
>> -{
>> - struct tegra_dma *tdma = dev_get_drvdata(dev);
>> - int ret;
>> -
>> - ret = clk_prepare_enable(tdma->dma_clk);
>> - if (ret < 0) {
>> - dev_err(dev, "clk_enable failed: %d\n", ret);
>> - return ret;
>> - }
>> - 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 = pm_runtime_get_sync(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++) {
>> @@ -1543,21 +1515,21 @@ static int tegra_dma_pm_suspend(struct device
>> *dev)
>> TEGRA_APBDMA_CHAN_WCOUNT);
>> }
>>
>> - /* Disable clock */
>> - pm_runtime_put(dev);
>> + clk_disable_unprepare(tdma->dma_clk);
>> +
>> return 0;
>> }
>>
>> -static int tegra_dma_pm_resume(struct device *dev)
>> +static int tegra_dma_runtime_resume(struct device *dev)
>> {
>> struct tegra_dma *tdma = dev_get_drvdata(dev);
>> - int i;
>> - int ret;
>> + int i, ret;
>>
>> - /* Enable clock before accessing register */
>> - ret = pm_runtime_get_sync(dev);
>> - if (ret < 0)
>> + ret = clk_prepare_enable(tdma->dma_clk);
>> + if (ret < 0) {
>> + dev_err(dev, "clk_enable failed: %d\n", ret);
>> return ret;
>> + }
>>
>> tdma_write(tdma, TEGRA_APBDMA_GENERAL, tdma->reg_gen);
>> tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
>> @@ -1582,10 +1554,19 @@ static int tegra_dma_pm_resume(struct device
>> *dev)
>> (ch_reg->csr & ~TEGRA_APBDMA_CSR_ENB));
>> }
>>
>> - /* Disable clock */
>> - pm_runtime_put(dev);
>> return 0;
>> }
>> +
>> +#ifdef CONFIG_PM_SLEEP
>> +static int tegra_dma_pm_suspend(struct device *dev)
>> +{
>> + return pm_runtime_force_suspend(dev);
>> +}
>> +
>> +static int tegra_dma_pm_resume(struct device *dev)
>> +{
>> + return pm_runtime_force_resume(dev);
>> +}
>> #endif
>
> You could just have SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> pm_runtime_force_resume)
Yes indeed! Will update.
Cheers
Jon
--
nvpublic
--
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
