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-rw-r--r--include/linux/acpi_dma.h121
1 files changed, 121 insertions, 0 deletions
diff --git a/include/linux/acpi_dma.h b/include/linux/acpi_dma.h
new file mode 100644
index 000000000..329436d38
--- /dev/null
+++ b/include/linux/acpi_dma.h
@@ -0,0 +1,121 @@
+/*
+ * ACPI helpers for DMA request / controller
+ *
+ * Based on of_dma.h
+ *
+ * Copyright (C) 2013, Intel Corporation
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __LINUX_ACPI_DMA_H
+#define __LINUX_ACPI_DMA_H
+
+#include <linux/list.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/dmaengine.h>
+
+/**
+ * struct acpi_dma_spec - slave device DMA resources
+ * @chan_id: channel unique id
+ * @slave_id: request line unique id
+ * @dev: struct device of the DMA controller to be used in the filter
+ * function
+ */
+struct acpi_dma_spec {
+ int chan_id;
+ int slave_id;
+ struct device *dev;
+};
+
+/**
+ * struct acpi_dma - representation of the registered DMAC
+ * @dma_controllers: linked list node
+ * @dev: struct device of this controller
+ * @acpi_dma_xlate: callback function to find a suitable channel
+ * @data: private data used by a callback function
+ * @base_request_line: first supported request line (CSRT)
+ * @end_request_line: last supported request line (CSRT)
+ */
+struct acpi_dma {
+ struct list_head dma_controllers;
+ struct device *dev;
+ struct dma_chan *(*acpi_dma_xlate)
+ (struct acpi_dma_spec *, struct acpi_dma *);
+ void *data;
+ unsigned short base_request_line;
+ unsigned short end_request_line;
+};
+
+/* Used with acpi_dma_simple_xlate() */
+struct acpi_dma_filter_info {
+ dma_cap_mask_t dma_cap;
+ dma_filter_fn filter_fn;
+};
+
+#ifdef CONFIG_DMA_ACPI
+
+int acpi_dma_controller_register(struct device *dev,
+ struct dma_chan *(*acpi_dma_xlate)
+ (struct acpi_dma_spec *, struct acpi_dma *),
+ void *data);
+int acpi_dma_controller_free(struct device *dev);
+int devm_acpi_dma_controller_register(struct device *dev,
+ struct dma_chan *(*acpi_dma_xlate)
+ (struct acpi_dma_spec *, struct acpi_dma *),
+ void *data);
+void devm_acpi_dma_controller_free(struct device *dev);
+
+struct dma_chan *acpi_dma_request_slave_chan_by_index(struct device *dev,
+ size_t index);
+struct dma_chan *acpi_dma_request_slave_chan_by_name(struct device *dev,
+ const char *name);
+
+struct dma_chan *acpi_dma_simple_xlate(struct acpi_dma_spec *dma_spec,
+ struct acpi_dma *adma);
+#else
+
+static inline int acpi_dma_controller_register(struct device *dev,
+ struct dma_chan *(*acpi_dma_xlate)
+ (struct acpi_dma_spec *, struct acpi_dma *),
+ void *data)
+{
+ return -ENODEV;
+}
+static inline int acpi_dma_controller_free(struct device *dev)
+{
+ return -ENODEV;
+}
+static inline int devm_acpi_dma_controller_register(struct device *dev,
+ struct dma_chan *(*acpi_dma_xlate)
+ (struct acpi_dma_spec *, struct acpi_dma *),
+ void *data)
+{
+ return -ENODEV;
+}
+static inline void devm_acpi_dma_controller_free(struct device *dev)
+{
+}
+
+static inline struct dma_chan *acpi_dma_request_slave_chan_by_index(
+ struct device *dev, size_t index)
+{
+ return ERR_PTR(-ENODEV);
+}
+static inline struct dma_chan *acpi_dma_request_slave_chan_by_name(
+ struct device *dev, const char *name)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+#define acpi_dma_simple_xlate NULL
+
+#endif
+
+#define acpi_dma_request_slave_channel acpi_dma_request_slave_chan_by_index
+
+#endif /* __LINUX_ACPI_DMA_H */