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Diffstat (limited to 'include/linux/comedi/comedi_isadma.h')
-rw-r--r--include/linux/comedi/comedi_isadma.h114
1 files changed, 114 insertions, 0 deletions
diff --git a/include/linux/comedi/comedi_isadma.h b/include/linux/comedi/comedi_isadma.h
new file mode 100644
index 000000000000..9d2b12db7e6e
--- /dev/null
+++ b/include/linux/comedi/comedi_isadma.h
@@ -0,0 +1,114 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * COMEDI ISA DMA support functions
+ * Copyright (c) 2014 H Hartley Sweeten <hsweeten@visionengravers.com>
+ */
+
+#ifndef _COMEDI_ISADMA_H
+#define _COMEDI_ISADMA_H
+
+#include <linux/types.h>
+
+struct comedi_device;
+struct device;
+
+/*
+ * These are used to avoid issues when <asm/dma.h> and the DMA_MODE_
+ * defines are not available.
+ */
+#define COMEDI_ISADMA_READ 0
+#define COMEDI_ISADMA_WRITE 1
+
+/**
+ * struct comedi_isadma_desc - cookie for ISA DMA
+ * @virt_addr: virtual address of buffer
+ * @hw_addr: hardware (bus) address of buffer
+ * @chan: DMA channel
+ * @maxsize: allocated size of buffer (in bytes)
+ * @size: transfer size (in bytes)
+ * @mode: DMA_MODE_READ or DMA_MODE_WRITE
+ */
+struct comedi_isadma_desc {
+ void *virt_addr;
+ dma_addr_t hw_addr;
+ unsigned int chan;
+ unsigned int maxsize;
+ unsigned int size;
+ char mode;
+};
+
+/**
+ * struct comedi_isadma - ISA DMA data
+ * @dev: device to allocate non-coherent memory for
+ * @desc: cookie for each DMA buffer
+ * @n_desc: the number of cookies
+ * @cur_dma: the current cookie in use
+ * @chan: the first DMA channel requested
+ * @chan2: the second DMA channel requested
+ */
+struct comedi_isadma {
+ struct device *dev;
+ struct comedi_isadma_desc *desc;
+ int n_desc;
+ int cur_dma;
+ unsigned int chan;
+ unsigned int chan2;
+};
+
+#if IS_ENABLED(CONFIG_ISA_DMA_API)
+
+void comedi_isadma_program(struct comedi_isadma_desc *desc);
+unsigned int comedi_isadma_disable(unsigned int dma_chan);
+unsigned int comedi_isadma_disable_on_sample(unsigned int dma_chan,
+ unsigned int size);
+unsigned int comedi_isadma_poll(struct comedi_isadma *dma);
+void comedi_isadma_set_mode(struct comedi_isadma_desc *desc, char dma_dir);
+
+struct comedi_isadma *comedi_isadma_alloc(struct comedi_device *dev,
+ int n_desc, unsigned int dma_chan1,
+ unsigned int dma_chan2,
+ unsigned int maxsize, char dma_dir);
+void comedi_isadma_free(struct comedi_isadma *dma);
+
+#else /* !IS_ENABLED(CONFIG_ISA_DMA_API) */
+
+static inline void comedi_isadma_program(struct comedi_isadma_desc *desc)
+{
+}
+
+static inline unsigned int comedi_isadma_disable(unsigned int dma_chan)
+{
+ return 0;
+}
+
+static inline unsigned int
+comedi_isadma_disable_on_sample(unsigned int dma_chan, unsigned int size)
+{
+ return 0;
+}
+
+static inline unsigned int comedi_isadma_poll(struct comedi_isadma *dma)
+{
+ return 0;
+}
+
+static inline void comedi_isadma_set_mode(struct comedi_isadma_desc *desc,
+ char dma_dir)
+{
+}
+
+static inline struct comedi_isadma *
+comedi_isadma_alloc(struct comedi_device *dev, int n_desc,
+ unsigned int dma_chan1, unsigned int dma_chan2,
+ unsigned int maxsize, char dma_dir)
+{
+ return NULL;
+}
+
+static inline void comedi_isadma_free(struct comedi_isadma *dma)
+{
+}
+
+#endif /* !IS_ENABLED(CONFIG_ISA_DMA_API) */
+
+#endif /* #ifndef _COMEDI_ISADMA_H */