dmaengine: append hsu DMA driver

The HSU DMA is developed to support High Speed UART controllers found in
particular on Intel MID platforms such as Intel Medfield.

The existing implementation is tighten to the drivers/tty/serial/mfd.c driver
and has a lot of disadvantages. Besides that we would like to get rid of the
old HS UART driver in regarding to extending the 8250 which supports generic
DMAEngine API. That's why the current driver has been developed.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 73 insertions, 0 deletions

diff --git a/include/linux/dma/hsu.h b/include/linux/dma/hsu.h
new file mode 100644
index 000000000000..234393a6997b
--- /dev/null
+++ b/include/linux/dma/hsu.h
@@ -0,0 +1,48 @@
+/*
+ * Driver for the High Speed UART DMA
+ *
+ * Copyright (C) 2015 Intel Corporation
+ *
+ * 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 _DMA_HSU_H
+#define _DMA_HSU_H
+
+#include <linux/device.h>
+#include <linux/interrupt.h>
+
+#include <linux/platform_data/dma-hsu.h>
+
+struct hsu_dma;
+
+/**
+ * struct hsu_dma_chip - representation of HSU DMA hardware
+ * @dev:                 struct device of the DMA controller
+ * @irq:                 irq line
+ * @regs:                memory mapped I/O space
+ * @length:              I/O space length
+ * @offset:              offset of the I/O space where registers are located
+ * @hsu:                 struct hsu_dma that is filed by ->probe()
+ * @pdata:               platform data for the DMA controller if provided
+ */
+struct hsu_dma_chip {
+        struct device                   *dev;
+        int                             irq;
+        void __iomem                    *regs;
+        unsigned int                    length;
+        unsigned int                    offset;
+        struct hsu_dma                  *hsu;
+        struct hsu_dma_platform_data    *pdata;
+};
+
+/* Export to the internal users */
+irqreturn_t hsu_dma_irq(struct hsu_dma_chip *chip, unsigned short nr);
+
+/* Export to the platform drivers */
+int hsu_dma_probe(struct hsu_dma_chip *chip);
+int hsu_dma_remove(struct hsu_dma_chip *chip);
+
+#endif /* _DMA_HSU_H */
diff --git a/include/linux/platform_data/dma-hsu.h b/include/linux/platform_data/dma-hsu.h
new file mode 100644
index 000000000000..8a1f6a4920b2
--- /dev/null
+++ b/include/linux/platform_data/dma-hsu.h
@@ -0,0 +1,25 @@
+/*
+ * Driver for the High Speed UART DMA
+ *
+ * Copyright (C) 2015 Intel Corporation
+ *
+ * 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 _PLATFORM_DATA_DMA_HSU_H
+#define _PLATFORM_DATA_DMA_HSU_H
+
+#include <linux/device.h>
+
+struct hsu_dma_slave {
+        struct device   *dma_dev;
+        int             chan_id;
+};
+
+struct hsu_dma_platform_data {
+        unsigned short  nr_channels;
+};
+
+#endif /* _PLATFORM_DATA_DMA_HSU_H */