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Diffstat (limited to 'drivers/dma/dw/acpi.c')
-rw-r--r--drivers/dma/dw/acpi.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/drivers/dma/dw/acpi.c b/drivers/dma/dw/acpi.c
new file mode 100644
index 000000000..c510c109d
--- /dev/null
+++ b/drivers/dma/dw/acpi.c
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2013,2019 Intel Corporation
+
+#include <linux/acpi.h>
+#include <linux/acpi_dma.h>
+
+#include "internal.h"
+
+static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
+{
+ struct acpi_dma_spec *dma_spec = param;
+ struct dw_dma_slave slave = {
+ .dma_dev = dma_spec->dev,
+ .src_id = dma_spec->slave_id,
+ .dst_id = dma_spec->slave_id,
+ .m_master = 0,
+ .p_master = 1,
+ };
+
+ return dw_dma_filter(chan, &slave);
+}
+
+void dw_dma_acpi_controller_register(struct dw_dma *dw)
+{
+ struct device *dev = dw->dma.dev;
+ struct acpi_dma_filter_info *info;
+ int ret;
+
+ if (!has_acpi_companion(dev))
+ return;
+
+ info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return;
+
+ dma_cap_zero(info->dma_cap);
+ dma_cap_set(DMA_SLAVE, info->dma_cap);
+ info->filter_fn = dw_dma_acpi_filter;
+
+ ret = acpi_dma_controller_register(dev, acpi_dma_simple_xlate, info);
+ if (ret)
+ dev_err(dev, "could not register acpi_dma_controller\n");
+}
+EXPORT_SYMBOL_GPL(dw_dma_acpi_controller_register);
+
+void dw_dma_acpi_controller_free(struct dw_dma *dw)
+{
+ struct device *dev = dw->dma.dev;
+
+ if (!has_acpi_companion(dev))
+ return;
+
+ acpi_dma_controller_free(dev);
+}
+EXPORT_SYMBOL_GPL(dw_dma_acpi_controller_free);