cregit-Linux how code gets into the kernel

Release 4.7 drivers/usb/musb/musb_dma.h

Directory: drivers/usb/musb
/*
 * 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)

#ifdef CONFIG_MUSB_PIO_ONLY

#define	is_dma_capable()	(0)
#else

#define	is_dma_capable()	(1)
#endif

#ifdef CONFIG_USB_UX500_DMA

#define musb_dma_ux500(musb)		(musb->io.quirks & MUSB_DMA_UX500)
#else

#define musb_dma_ux500(musb)		0
#endif

#ifdef CONFIG_USB_TI_CPPI41_DMA

#define musb_dma_cppi41(musb)		(musb->io.quirks & MUSB_DMA_CPPI41)
#else

#define musb_dma_cppi41(musb)		0
#endif

#ifdef CONFIG_USB_TI_CPPI_DMA

#define musb_dma_cppi(musb)		(musb->io.quirks & MUSB_DMA_CPPI)
#else

#define musb_dma_cppi(musb)		0
#endif

#ifdef CONFIG_USB_TUSB_OMAP_DMA

#define tusb_dma_omap(musb)		(musb->io.quirks & MUSB_DMA_TUSB_OMAP)
#else

#define tusb_dma_omap(musb)		0
#endif

#ifdef CONFIG_USB_INVENTRA_DMA

#define musb_dma_inventra(musb)		(musb->io.quirks & MUSB_DMA_INVENTRA)
#else

#define musb_dma_inventra(musb)		0
#endif

#if defined(CONFIG_USB_TI_CPPI_DMA) || defined(CONFIG_USB_TI_CPPI41_DMA)

#define	is_cppi_enabled(musb)		\
	(musb_dma_cppi(musb) || musb_dma_cppi41(musb))
#else

#define	is_cppi_enabled(musb)	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;
	
bool			rx_packet_done;
};

/*
 * 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; }

Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi27100.00%1100.00%
Total27100.00%1100.00%

/** * 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 { 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); #ifdef CONFIG_MUSB_PIO_ONLY
static inline struct dma_controller * musb_dma_controller_create(struct musb *m, void __iomem *io) { return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
sebastian andrzej siewiorsebastian andrzej siewior2195.45%150.00%
tony lindgrentony lindgren14.55%150.00%
Total22100.00%2100.00%


static inline void musb_dma_controller_destroy(struct dma_controller *d) { }

Contributors

PersonTokensPropCommitsCommitProp
sebastian andrzej siewiorsebastian andrzej siewior1090.91%150.00%
tony lindgrentony lindgren19.09%150.00%
Total11100.00%2100.00%

#else extern struct dma_controller * (*musb_dma_controller_create)(struct musb *, void __iomem *); extern void (*musb_dma_controller_destroy)(struct dma_controller *); #endif /* Platform specific DMA functions */ extern struct dma_controller * musbhs_dma_controller_create(struct musb *musb, void __iomem *base); extern void musbhs_dma_controller_destroy(struct dma_controller *c); extern struct dma_controller * tusb_dma_controller_create(struct musb *musb, void __iomem *base); extern void tusb_dma_controller_destroy(struct dma_controller *c); extern struct dma_controller * cppi_dma_controller_create(struct musb *musb, void __iomem *base); extern void cppi_dma_controller_destroy(struct dma_controller *c); extern struct dma_controller * cppi41_dma_controller_create(struct musb *musb, void __iomem *base); extern void cppi41_dma_controller_destroy(struct dma_controller *c); extern struct dma_controller * ux500_dma_controller_create(struct musb *musb, void __iomem *base); extern void ux500_dma_controller_destroy(struct dma_controller *c); #endif /* __MUSB_DMA_H__ */

Overall Contributors

PersonTokensPropCommitsCommitProp
tony lindgrentony lindgren25744.08%222.22%
felipe balbifelipe balbi24041.17%111.11%
sebastian andrzej siewiorsebastian andrzej siewior437.38%333.33%
mian yousaf kaukabmian yousaf kaukab223.77%111.11%
sonic zhangsonic zhang183.09%111.11%
daniel mackdaniel mack30.51%111.11%
Total583100.00%9100.00%
Directory: drivers/usb/musb
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
{% endraw %}