--- /dev/null
+/*
+ * MUSB OTG driver DMA controller abstraction
+ *
+ * Copyright 2005 Mentor Graphics Corporation
+ * Copyright (C) 2005-2006 by Texas Instruments
+ * Copyright (C) 2006-2007 Nokia 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef __MUSB_DMA_H__
+#define __MUSB_DMA_H__
+
+struct musb_hw_ep;
+
+/*
+ * DMA Controller Abstraction
+ *
+ * DMA Controllers are abstracted to allow use of a variety of different
+ * implementations of DMA, as allowed by the Inventra USB cores. On the
+ * host side, usbcore sets up the DMA mappings and flushes caches; on the
+ * peripheral side, the gadget controller driver does. Responsibilities
+ * of a DMA controller driver include:
+ *
+ * - Handling the details of moving multiple USB packets
+ * in cooperation with the Inventra USB core, including especially
+ * the correct RX side treatment of short packets and buffer-full
+ * states (both of which terminate transfers).
+ *
+ * - Knowing the correlation between dma channels and the
+ * Inventra core's local endpoint resources and data direction.
+ *
+ * - Maintaining a list of allocated/available channels.
+ *
+ * - Updating channel status on interrupts,
+ * whether shared with the Inventra core or separate.
+ */
+
+#define DMA_ADDR_INVALID (~(dma_addr_t)0)
+
+#ifndef CONFIG_MUSB_PIO_ONLY
+#define is_dma_capable() (1)
+#else
+#define is_dma_capable() (0)
+#endif
+
+#ifdef CONFIG_USB_TI_CPPI_DMA
+#define is_cppi_enabled() 1
+#else
+#define is_cppi_enabled() 0
+#endif
+
+#ifdef CONFIG_USB_TUSB_OMAP_DMA
+#define tusb_dma_omap() 1
+#else
+#define tusb_dma_omap() 0
+#endif
+
+/* Anomaly 05000456 - USB Receive Interrupt Is Not Generated in DMA Mode 1
+ * Only allow DMA mode 1 to be used when the USB will actually generate the
+ * interrupts we expect.
+ */
+#ifdef CONFIG_BLACKFIN
+# undef USE_MODE1
+# if !ANOMALY_05000456
+# define USE_MODE1
+# endif
+#endif
+
+/*
+ * DMA channel status ... updated by the dma controller driver whenever that
+ * status changes, and protected by the overall controller spinlock.
+ */
+enum dma_channel_status {
+ /* unallocated */
+ MUSB_DMA_STATUS_UNKNOWN,
+ /* allocated ... but not busy, no errors */
+ MUSB_DMA_STATUS_FREE,
+ /* busy ... transactions are active */
+ MUSB_DMA_STATUS_BUSY,
+ /* transaction(s) aborted due to ... dma or memory bus error */
+ MUSB_DMA_STATUS_BUS_ABORT,
+ /* transaction(s) aborted due to ... core error or USB fault */
+ MUSB_DMA_STATUS_CORE_ABORT
+};
+
+struct dma_controller;
+
+/**
+ * struct dma_channel - A DMA channel.
+ * @private_data: channel-private data
+ * @max_len: the maximum number of bytes the channel can move in one
+ * transaction (typically representing many USB maximum-sized packets)
+ * @actual_len: how many bytes have been transferred
+ * @status: current channel status (updated e.g. on interrupt)
+ * @desired_mode: true if mode 1 is desired; false if mode 0 is desired
+ *
+ * channels are associated with an endpoint for the duration of at least
+ * one usb transfer.
+ */
+struct dma_channel {
+ void *private_data;
+ /* FIXME not void* private_data, but a dma_controller * */
+ size_t max_len;
+ size_t actual_len;
+ enum dma_channel_status status;
+ bool desired_mode;
+};
+
+/*
+ * dma_channel_status - return status of dma channel
+ * @c: the channel
+ *
+ * Returns the software's view of the channel status. If that status is BUSY
+ * then it's possible that the hardware has completed (or aborted) a transfer,
+ * so the driver needs to update that status.
+ */
+static inline enum dma_channel_status
+dma_channel_status(struct dma_channel *c)
+{
+ return (is_dma_capable() && c) ? c->status : MUSB_DMA_STATUS_UNKNOWN;
+}
+
+/**
+ * struct dma_controller - A DMA Controller.
+ * @start: call this to start a DMA controller;
+ * return 0 on success, else negative errno
+ * @stop: call this to stop a DMA controller
+ * return 0 on success, else negative errno
+ * @channel_alloc: call this to allocate a DMA channel
+ * @channel_release: call this to release a DMA channel
+ * @channel_abort: call this to abort a pending DMA transaction,
+ * returning it to FREE (but allocated) state
+ *
+ * Controllers manage dma channels.
+ */
+struct dma_controller {
+ int (*start)(struct dma_controller *);
+ int (*stop)(struct dma_controller *);
+ struct dma_channel *(*channel_alloc)(struct dma_controller *,
+ struct musb_hw_ep *, u8 is_tx);
+ void (*channel_release)(struct dma_channel *);
+ int (*channel_program)(struct dma_channel *channel,
+ u16 maxpacket, u8 mode,
+ dma_addr_t dma_addr,
+ u32 length);
+ int (*channel_abort)(struct dma_channel *);
+ int (*is_compatible)(struct dma_channel *channel,
+ u16 maxpacket,
+ void *buf, u32 length);
+};
+
+/* called after channel_program(), may indicate a fault */
+extern void musb_dma_completion(struct musb *musb, u8 epnum, u8 transmit);
+
+
+extern struct dma_controller *__init
+dma_controller_create(struct musb *, void __iomem *);
+
+extern void dma_controller_destroy(struct dma_controller *);
+
+#endif /* __MUSB_DMA_H__ */
Code Review / kvmfornfv.git / blobdiff