initial_commit

1 files changed, 157 insertions, 0 deletions

diff --git a/arch/arm/mach-ep93xx/include/mach/dma.h b/arch/arm/mach-ep93xx/include/mach/dma.h
new file mode 100644
index 00000000..9be4b2dd
--- /dev/null
+++ b/arch/arm/mach-ep93xx/include/mach/dma.h
@@ -0,0 +1,157 @@
+/**
+ * DOC: EP93xx DMA M2P memory to peripheral and peripheral to memory engine
+ *
+ * The EP93xx DMA M2P subsystem handles DMA transfers between memory and
+ * peripherals. DMA M2P channels are available for audio, UARTs and IrDA.
+ * See chapter 10 of the EP93xx users guide for full details on the DMA M2P
+ * engine.
+ *
+ * See sound/soc/ep93xx/ep93xx-pcm.c for an example use of the DMA M2P code.
+ *
+ */
+
+#ifndef __ASM_ARCH_DMA_H
+#define __ASM_ARCH_DMA_H
+
+#include <linux/list.h>
+#include <linux/types.h>
+
+/**
+ * struct ep93xx_dma_buffer - Information about a buffer to be transferred
+ * using the DMA M2P engine
+ *
+ * @list: Entry in DMA buffer list
+ * @bus_addr: Physical address of the buffer
+ * @size: Size of the buffer in bytes
+ */
+struct ep93xx_dma_buffer {
+	struct list_head	list;
+	u32			bus_addr;
+	u16			size;
+};
+
+/**
+ * struct ep93xx_dma_m2p_client - Information about a DMA M2P client
+ *
+ * @name: Unique name for this client
+ * @flags: Client flags
+ * @cookie: User data to pass to callback functions
+ * @buffer_started: Non NULL function to call when a transfer is started.
+ * 			The arguments are the user data cookie and the DMA
+ *			buffer which is starting.
+ * @buffer_finished: Non NULL function to call when a transfer is completed.
+ *			The arguments are the user data cookie, the DMA buffer
+ *			which has completed, and a boolean flag indicating if
+ *			the transfer had an error.
+ */
+struct ep93xx_dma_m2p_client {
+	char			*name;
+	u8			flags;
+	void			*cookie;
+	void			(*buffer_started)(void *cookie,
+					struct ep93xx_dma_buffer *buf);
+	void			(*buffer_finished)(void *cookie,
+					struct ep93xx_dma_buffer *buf,
+					int bytes, int error);
+
+	/* private: Internal use only */
+	void			*channel;
+};
+
+/* DMA M2P ports */
+#define EP93XX_DMA_M2P_PORT_I2S1	0x00
+#define EP93XX_DMA_M2P_PORT_I2S2	0x01
+#define EP93XX_DMA_M2P_PORT_AAC1	0x02
+#define EP93XX_DMA_M2P_PORT_AAC2	0x03
+#define EP93XX_DMA_M2P_PORT_AAC3	0x04
+#define EP93XX_DMA_M2P_PORT_I2S3	0x05
+#define EP93XX_DMA_M2P_PORT_UART1	0x06
+#define EP93XX_DMA_M2P_PORT_UART2	0x07
+#define EP93XX_DMA_M2P_PORT_UART3	0x08
+#define EP93XX_DMA_M2P_PORT_IRDA	0x09
+#define EP93XX_DMA_M2P_PORT_MASK	0x0f
+
+/* DMA M2P client flags */
+#define EP93XX_DMA_M2P_TX		0x00	/* Memory to peripheral */
+#define EP93XX_DMA_M2P_RX		0x10	/* Peripheral to memory */
+
+/*
+ * DMA M2P client error handling flags. See the EP93xx users guide
+ * documentation on the DMA M2P CONTROL register for more details
+ */
+#define EP93XX_DMA_M2P_ABORT_ON_ERROR	0x20	/* Abort on peripheral error */
+#define EP93XX_DMA_M2P_IGNORE_ERROR	0x40	/* Ignore peripheral errors */
+#define EP93XX_DMA_M2P_ERROR_MASK	0x60	/* Mask of error bits */
+
+/**
+ * ep93xx_dma_m2p_client_register - Register a client with the DMA M2P
+ * subsystem
+ *
+ * @m2p: Client information to register
+ * returns 0 on success
+ *
+ * The DMA M2P subsystem allocates a channel and an interrupt line for the DMA
+ * client
+ */
+int ep93xx_dma_m2p_client_register(struct ep93xx_dma_m2p_client *m2p);
+
+/**
+ * ep93xx_dma_m2p_client_unregister - Unregister a client from the DMA M2P
+ * subsystem
+ *
+ * @m2p: Client to unregister
+ *
+ * Any transfers currently in progress will be completed in hardware, but
+ * ignored in software.
+ */
+void ep93xx_dma_m2p_client_unregister(struct ep93xx_dma_m2p_client *m2p);
+
+/**
+ * ep93xx_dma_m2p_submit - Submit a DMA M2P transfer
+ *
+ * @m2p: DMA Client to submit the transfer on
+ * @buf: DMA Buffer to submit
+ *
+ * If the current or next transfer positions are free on the M2P client then
+ * the transfer is started immediately. If not, the transfer is added to the
+ * list of pending transfers. This function must not be called from the
+ * buffer_finished callback for an M2P channel.
+ *
+ */
+void ep93xx_dma_m2p_submit(struct ep93xx_dma_m2p_client *m2p,
+			   struct ep93xx_dma_buffer *buf);
+
+/**
+ * ep93xx_dma_m2p_submit_recursive - Put a DMA transfer on the pending list
+ * for an M2P channel
+ *
+ * @m2p: DMA Client to submit the transfer on
+ * @buf: DMA Buffer to submit
+ *
+ * This function must only be called from the buffer_finished callback for an
+ * M2P channel. It is commonly used to add the next transfer in a chained list
+ * of DMA transfers.
+ */
+void ep93xx_dma_m2p_submit_recursive(struct ep93xx_dma_m2p_client *m2p,
+				     struct ep93xx_dma_buffer *buf);
+
+/**
+ * ep93xx_dma_m2p_flush - Flush all pending transfers on a DMA M2P client
+ *
+ * @m2p: DMA client to flush transfers on
+ *
+ * Any transfers currently in progress will be completed in hardware, but
+ * ignored in software.
+ *
+ */
+static inline enum dma_transfer_direction
+ep93xx_dma_chan_direction(struct dma_chan *chan)
+{
+	if (!ep93xx_dma_chan_is_m2p(chan))
+		return DMA_NONE;
+
+	/* even channels are for TX, odd for RX */
+	return (chan->chan_id % 2 == 0) ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
+}
+
+#endif /* __ASM_ARCH_DMA_H */