linux/drivers/usb/musb/musb_dma.h
<<
>>
Prefs
   1/*
   2 * MUSB OTG driver DMA controller abstraction
   3 *
   4 * Copyright 2005 Mentor Graphics Corporation
   5 * Copyright (C) 2005-2006 by Texas Instruments
   6 * Copyright (C) 2006-2007 Nokia Corporation
   7 *
   8 * This program is free software; you can redistribute it and/or
   9 * modify it under the terms of the GNU General Public License
  10 * version 2 as published by the Free Software Foundation.
  11 *
  12 * This program is distributed in the hope that it will be useful, but
  13 * WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 * General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU General Public License
  18 * along with this program; if not, write to the Free Software
  19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  20 * 02110-1301 USA
  21 *
  22 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
  23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
  25 * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  28 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
  29 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32 *
  33 */
  34
  35#ifndef __MUSB_DMA_H__
  36#define __MUSB_DMA_H__
  37
  38struct musb_hw_ep;
  39
  40/*
  41 * DMA Controller Abstraction
  42 *
  43 * DMA Controllers are abstracted to allow use of a variety of different
  44 * implementations of DMA, as allowed by the Inventra USB cores.  On the
  45 * host side, usbcore sets up the DMA mappings and flushes caches; on the
  46 * peripheral side, the gadget controller driver does.  Responsibilities
  47 * of a DMA controller driver include:
  48 *
  49 *  - Handling the details of moving multiple USB packets
  50 *    in cooperation with the Inventra USB core, including especially
  51 *    the correct RX side treatment of short packets and buffer-full
  52 *    states (both of which terminate transfers).
  53 *
  54 *  - Knowing the correlation between dma channels and the
  55 *    Inventra core's local endpoint resources and data direction.
  56 *
  57 *  - Maintaining a list of allocated/available channels.
  58 *
  59 *  - Updating channel status on interrupts,
  60 *    whether shared with the Inventra core or separate.
  61 */
  62
  63#define DMA_ADDR_INVALID        (~(dma_addr_t)0)
  64
  65#ifdef CONFIG_MUSB_PIO_ONLY
  66#define is_dma_capable()        (0)
  67#else
  68#define is_dma_capable()        (1)
  69#endif
  70
  71#ifdef CONFIG_USB_UX500_DMA
  72#define musb_dma_ux500(musb)            (musb->io.quirks & MUSB_DMA_UX500)
  73#else
  74#define musb_dma_ux500(musb)            0
  75#endif
  76
  77#ifdef CONFIG_USB_TI_CPPI41_DMA
  78#define musb_dma_cppi41(musb)           (musb->io.quirks & MUSB_DMA_CPPI41)
  79#else
  80#define musb_dma_cppi41(musb)           0
  81#endif
  82
  83#ifdef CONFIG_USB_TI_CPPI_DMA
  84#define musb_dma_cppi(musb)             (musb->io.quirks & MUSB_DMA_CPPI)
  85#else
  86#define musb_dma_cppi(musb)             0
  87#endif
  88
  89#ifdef CONFIG_USB_TUSB_OMAP_DMA
  90#define tusb_dma_omap(musb)             (musb->io.quirks & MUSB_DMA_TUSB_OMAP)
  91#else
  92#define tusb_dma_omap(musb)             0
  93#endif
  94
  95#ifdef CONFIG_USB_INVENTRA_DMA
  96#define musb_dma_inventra(musb)         (musb->io.quirks & MUSB_DMA_INVENTRA)
  97#else
  98#define musb_dma_inventra(musb)         0
  99#endif
 100
 101#if defined(CONFIG_USB_TI_CPPI_DMA) || defined(CONFIG_USB_TI_CPPI41_DMA)
 102#define is_cppi_enabled(musb)           \
 103        (musb_dma_cppi(musb) || musb_dma_cppi41(musb))
 104#else
 105#define is_cppi_enabled(musb)   0
 106#endif
 107
 108/* Anomaly 05000456 - USB Receive Interrupt Is Not Generated in DMA Mode 1
 109 *      Only allow DMA mode 1 to be used when the USB will actually generate the
 110 *      interrupts we expect.
 111 */
 112#ifdef CONFIG_BLACKFIN
 113# undef USE_MODE1
 114# if !ANOMALY_05000456
 115#  define USE_MODE1
 116# endif
 117#endif
 118
 119/*
 120 * DMA channel status ... updated by the dma controller driver whenever that
 121 * status changes, and protected by the overall controller spinlock.
 122 */
 123enum dma_channel_status {
 124        /* unallocated */
 125        MUSB_DMA_STATUS_UNKNOWN,
 126        /* allocated ... but not busy, no errors */
 127        MUSB_DMA_STATUS_FREE,
 128        /* busy ... transactions are active */
 129        MUSB_DMA_STATUS_BUSY,
 130        /* transaction(s) aborted due to ... dma or memory bus error */
 131        MUSB_DMA_STATUS_BUS_ABORT,
 132        /* transaction(s) aborted due to ... core error or USB fault */
 133        MUSB_DMA_STATUS_CORE_ABORT
 134};
 135
 136struct dma_controller;
 137
 138/**
 139 * struct dma_channel - A DMA channel.
 140 * @private_data: channel-private data
 141 * @max_len: the maximum number of bytes the channel can move in one
 142 *      transaction (typically representing many USB maximum-sized packets)
 143 * @actual_len: how many bytes have been transferred
 144 * @status: current channel status (updated e.g. on interrupt)
 145 * @desired_mode: true if mode 1 is desired; false if mode 0 is desired
 146 *
 147 * channels are associated with an endpoint for the duration of at least
 148 * one usb transfer.
 149 */
 150struct dma_channel {
 151        void                    *private_data;
 152        /* FIXME not void* private_data, but a dma_controller * */
 153        size_t                  max_len;
 154        size_t                  actual_len;
 155        enum dma_channel_status status;
 156        bool                    desired_mode;
 157        bool                    rx_packet_done;
 158};
 159
 160/*
 161 * dma_channel_status - return status of dma channel
 162 * @c: the channel
 163 *
 164 * Returns the software's view of the channel status.  If that status is BUSY
 165 * then it's possible that the hardware has completed (or aborted) a transfer,
 166 * so the driver needs to update that status.
 167 */
 168static inline enum dma_channel_status
 169dma_channel_status(struct dma_channel *c)
 170{
 171        return (is_dma_capable() && c) ? c->status : MUSB_DMA_STATUS_UNKNOWN;
 172}
 173
 174/**
 175 * struct dma_controller - A DMA Controller.
 176 * @musb: the usb controller
 177 * @start: call this to start a DMA controller;
 178 *      return 0 on success, else negative errno
 179 * @stop: call this to stop a DMA controller
 180 *      return 0 on success, else negative errno
 181 * @channel_alloc: call this to allocate a DMA channel
 182 * @channel_release: call this to release a DMA channel
 183 * @channel_abort: call this to abort a pending DMA transaction,
 184 *      returning it to FREE (but allocated) state
 185 * @dma_callback: invoked on DMA completion, useful to run platform
 186 *      code such IRQ acknowledgment.
 187 *
 188 * Controllers manage dma channels.
 189 */
 190struct dma_controller {
 191        struct musb *musb;
 192        struct dma_channel      *(*channel_alloc)(struct dma_controller *,
 193                                        struct musb_hw_ep *, u8 is_tx);
 194        void                    (*channel_release)(struct dma_channel *);
 195        int                     (*channel_program)(struct dma_channel *channel,
 196                                                        u16 maxpacket, u8 mode,
 197                                                        dma_addr_t dma_addr,
 198                                                        u32 length);
 199        int                     (*channel_abort)(struct dma_channel *);
 200        int                     (*is_compatible)(struct dma_channel *channel,
 201                                                        u16 maxpacket,
 202                                                        void *buf, u32 length);
 203        void                    (*dma_callback)(struct dma_controller *);
 204};
 205
 206/* called after channel_program(), may indicate a fault */
 207extern void musb_dma_completion(struct musb *musb, u8 epnum, u8 transmit);
 208
 209#ifdef CONFIG_MUSB_PIO_ONLY
 210static inline struct dma_controller *
 211musb_dma_controller_create(struct musb *m, void __iomem *io)
 212{
 213        return NULL;
 214}
 215
 216static inline void musb_dma_controller_destroy(struct dma_controller *d) { }
 217
 218#else
 219
 220extern struct dma_controller *
 221(*musb_dma_controller_create)(struct musb *, void __iomem *);
 222
 223extern void (*musb_dma_controller_destroy)(struct dma_controller *);
 224#endif
 225
 226/* Platform specific DMA functions */
 227extern struct dma_controller *
 228musbhs_dma_controller_create(struct musb *musb, void __iomem *base);
 229extern void musbhs_dma_controller_destroy(struct dma_controller *c);
 230
 231extern struct dma_controller *
 232tusb_dma_controller_create(struct musb *musb, void __iomem *base);
 233extern void tusb_dma_controller_destroy(struct dma_controller *c);
 234
 235extern struct dma_controller *
 236cppi_dma_controller_create(struct musb *musb, void __iomem *base);
 237extern void cppi_dma_controller_destroy(struct dma_controller *c);
 238
 239extern struct dma_controller *
 240cppi41_dma_controller_create(struct musb *musb, void __iomem *base);
 241extern void cppi41_dma_controller_destroy(struct dma_controller *c);
 242
 243extern struct dma_controller *
 244ux500_dma_controller_create(struct musb *musb, void __iomem *base);
 245extern void ux500_dma_controller_destroy(struct dma_controller *c);
 246
 247#endif  /* __MUSB_DMA_H__ */
 248