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>>> >>> + if (!of_property_present(i2c_dev->dev->of_node, "dmas")) { >>> + dev_dbg(i2c_dev->dev, "DMA not available, falling back to PIO\n"); >>> + return 0; >>> + } >>> + >>> if (i2c_dev->hw->has_apb_dma) { >>> if (!IS_ENABLED(CONFIG_TEGRA20_APB_DMA)) { >>> dev_dbg(i2c_dev->dev, "APB DMA support not enabled\n"); >> >> What about ACPI based devices? > > The of_ function returns false if using ACPI. Since these DMA drivers does > not support ACPI enumeration currently, we would not require to proceed > further anyway. But if required we can add an additional check with > acpi_dma_supported() or similar. Do you suggest adding a check for ACPI? I was just wondering if it is better to use fwnode_property_present() instead. Jon -- nvpublic