173 lines
5.7 KiB
C
173 lines
5.7 KiB
C
/*
|
|
* 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
|
|
|
|
/*
|
|
* 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 *);
|
|
};
|
|
|
|
/* 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__ */
|