Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / usb / musb / tusb6010_omap.c
diff --git a/kernel/drivers/usb/musb/tusb6010_omap.c b/kernel/drivers/usb/musb/tusb6010_omap.c
new file mode 100644 (file)
index 0000000..3ce152c
--- /dev/null
@@ -0,0 +1,707 @@
+/*
+ * TUSB6010 USB 2.0 OTG Dual Role controller OMAP DMA interface
+ *
+ * Copyright (C) 2006 Nokia Corporation
+ * Tony Lindgren <tony@atomide.com>
+ *
+ * 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.
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/usb.h>
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/omap-dma.h>
+
+#include "musb_core.h"
+#include "tusb6010.h"
+
+#define to_chdat(c)            ((struct tusb_omap_dma_ch *)(c)->private_data)
+
+#define MAX_DMAREQ             5       /* REVISIT: Really 6, but req5 not OK */
+
+#define OMAP24XX_DMA_EXT_DMAREQ0       2
+#define OMAP24XX_DMA_EXT_DMAREQ1       3
+#define OMAP242X_DMA_EXT_DMAREQ2       14
+#define OMAP242X_DMA_EXT_DMAREQ3       15
+#define OMAP242X_DMA_EXT_DMAREQ4       16
+#define OMAP242X_DMA_EXT_DMAREQ5       64
+
+struct tusb_omap_dma_ch {
+       struct musb             *musb;
+       void __iomem            *tbase;
+       unsigned long           phys_offset;
+       int                     epnum;
+       u8                      tx;
+       struct musb_hw_ep       *hw_ep;
+
+       int                     ch;
+       s8                      dmareq;
+       s8                      sync_dev;
+
+       struct tusb_omap_dma    *tusb_dma;
+
+       dma_addr_t              dma_addr;
+
+       u32                     len;
+       u16                     packet_sz;
+       u16                     transfer_packet_sz;
+       u32                     transfer_len;
+       u32                     completed_len;
+};
+
+struct tusb_omap_dma {
+       struct dma_controller           controller;
+       struct musb                     *musb;
+       void __iomem                    *tbase;
+
+       int                             ch;
+       s8                              dmareq;
+       s8                              sync_dev;
+       unsigned                        multichannel:1;
+};
+
+/*
+ * Allocate dmareq0 to the current channel unless it's already taken
+ */
+static inline int tusb_omap_use_shared_dmareq(struct tusb_omap_dma_ch *chdat)
+{
+       u32             reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
+
+       if (reg != 0) {
+               dev_dbg(chdat->musb->controller, "ep%i dmareq0 is busy for ep%i\n",
+                       chdat->epnum, reg & 0xf);
+               return -EAGAIN;
+       }
+
+       if (chdat->tx)
+               reg = (1 << 4) | chdat->epnum;
+       else
+               reg = chdat->epnum;
+
+       musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
+
+       return 0;
+}
+
+static inline void tusb_omap_free_shared_dmareq(struct tusb_omap_dma_ch *chdat)
+{
+       u32             reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
+
+       if ((reg & 0xf) != chdat->epnum) {
+               printk(KERN_ERR "ep%i trying to release dmareq0 for ep%i\n",
+                       chdat->epnum, reg & 0xf);
+               return;
+       }
+       musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, 0);
+}
+
+/*
+ * See also musb_dma_completion in plat_uds.c and musb_g_[tx|rx]() in
+ * musb_gadget.c.
+ */
+static void tusb_omap_dma_cb(int lch, u16 ch_status, void *data)
+{
+       struct dma_channel      *channel = (struct dma_channel *)data;
+       struct tusb_omap_dma_ch *chdat = to_chdat(channel);
+       struct tusb_omap_dma    *tusb_dma = chdat->tusb_dma;
+       struct musb             *musb = chdat->musb;
+       struct device           *dev = musb->controller;
+       struct musb_hw_ep       *hw_ep = chdat->hw_ep;
+       void __iomem            *ep_conf = hw_ep->conf;
+       void __iomem            *mbase = musb->mregs;
+       unsigned long           remaining, flags, pio;
+       int                     ch;
+
+       spin_lock_irqsave(&musb->lock, flags);
+
+       if (tusb_dma->multichannel)
+               ch = chdat->ch;
+       else
+               ch = tusb_dma->ch;
+
+       if (ch_status != OMAP_DMA_BLOCK_IRQ)
+               printk(KERN_ERR "TUSB DMA error status: %i\n", ch_status);
+
+       dev_dbg(musb->controller, "ep%i %s dma callback ch: %i status: %x\n",
+               chdat->epnum, chdat->tx ? "tx" : "rx",
+               ch, ch_status);
+
+       if (chdat->tx)
+               remaining = musb_readl(ep_conf, TUSB_EP_TX_OFFSET);
+       else
+               remaining = musb_readl(ep_conf, TUSB_EP_RX_OFFSET);
+
+       remaining = TUSB_EP_CONFIG_XFR_SIZE(remaining);
+
+       /* HW issue #10: XFR_SIZE may get corrupt on DMA (both async & sync) */
+       if (unlikely(remaining > chdat->transfer_len)) {
+               dev_dbg(musb->controller, "Corrupt %s dma ch%i XFR_SIZE: 0x%08lx\n",
+                       chdat->tx ? "tx" : "rx", chdat->ch,
+                       remaining);
+               remaining = 0;
+       }
+
+       channel->actual_len = chdat->transfer_len - remaining;
+       pio = chdat->len - channel->actual_len;
+
+       dev_dbg(musb->controller, "DMA remaining %lu/%u\n", remaining, chdat->transfer_len);
+
+       /* Transfer remaining 1 - 31 bytes */
+       if (pio > 0 && pio < 32) {
+               u8      *buf;
+
+               dev_dbg(musb->controller, "Using PIO for remaining %lu bytes\n", pio);
+               buf = phys_to_virt((u32)chdat->dma_addr) + chdat->transfer_len;
+               if (chdat->tx) {
+                       dma_unmap_single(dev, chdat->dma_addr,
+                                               chdat->transfer_len,
+                                               DMA_TO_DEVICE);
+                       musb_write_fifo(hw_ep, pio, buf);
+               } else {
+                       dma_unmap_single(dev, chdat->dma_addr,
+                                               chdat->transfer_len,
+                                               DMA_FROM_DEVICE);
+                       musb_read_fifo(hw_ep, pio, buf);
+               }
+               channel->actual_len += pio;
+       }
+
+       if (!tusb_dma->multichannel)
+               tusb_omap_free_shared_dmareq(chdat);
+
+       channel->status = MUSB_DMA_STATUS_FREE;
+
+       /* Handle only RX callbacks here. TX callbacks must be handled based
+        * on the TUSB DMA status interrupt.
+        * REVISIT: Use both TUSB DMA status interrupt and OMAP DMA callback
+        * interrupt for RX and TX.
+        */
+       if (!chdat->tx)
+               musb_dma_completion(musb, chdat->epnum, chdat->tx);
+
+       /* We must terminate short tx transfers manually by setting TXPKTRDY.
+        * REVISIT: This same problem may occur with other MUSB dma as well.
+        * Easy to test with g_ether by pinging the MUSB board with ping -s54.
+        */
+       if ((chdat->transfer_len < chdat->packet_sz)
+                       || (chdat->transfer_len % chdat->packet_sz != 0)) {
+               u16     csr;
+
+               if (chdat->tx) {
+                       dev_dbg(musb->controller, "terminating short tx packet\n");
+                       musb_ep_select(mbase, chdat->epnum);
+                       csr = musb_readw(hw_ep->regs, MUSB_TXCSR);
+                       csr |= MUSB_TXCSR_MODE | MUSB_TXCSR_TXPKTRDY
+                               | MUSB_TXCSR_P_WZC_BITS;
+                       musb_writew(hw_ep->regs, MUSB_TXCSR, csr);
+               }
+       }
+
+       spin_unlock_irqrestore(&musb->lock, flags);
+}
+
+static int tusb_omap_dma_program(struct dma_channel *channel, u16 packet_sz,
+                               u8 rndis_mode, dma_addr_t dma_addr, u32 len)
+{
+       struct tusb_omap_dma_ch         *chdat = to_chdat(channel);
+       struct tusb_omap_dma            *tusb_dma = chdat->tusb_dma;
+       struct musb                     *musb = chdat->musb;
+       struct device                   *dev = musb->controller;
+       struct musb_hw_ep               *hw_ep = chdat->hw_ep;
+       void __iomem                    *mbase = musb->mregs;
+       void __iomem                    *ep_conf = hw_ep->conf;
+       dma_addr_t                      fifo = hw_ep->fifo_sync;
+       struct omap_dma_channel_params  dma_params;
+       u32                             dma_remaining;
+       int                             src_burst, dst_burst;
+       u16                             csr;
+       int                             ch;
+       s8                              dmareq;
+       s8                              sync_dev;
+
+       if (unlikely(dma_addr & 0x1) || (len < 32) || (len > packet_sz))
+               return false;
+
+       /*
+        * HW issue #10: Async dma will eventually corrupt the XFR_SIZE
+        * register which will cause missed DMA interrupt. We could try to
+        * use a timer for the callback, but it is unsafe as the XFR_SIZE
+        * register is corrupt, and we won't know if the DMA worked.
+        */
+       if (dma_addr & 0x2)
+               return false;
+
+       /*
+        * Because of HW issue #10, it seems like mixing sync DMA and async
+        * PIO access can confuse the DMA. Make sure XFR_SIZE is reset before
+        * using the channel for DMA.
+        */
+       if (chdat->tx)
+               dma_remaining = musb_readl(ep_conf, TUSB_EP_TX_OFFSET);
+       else
+               dma_remaining = musb_readl(ep_conf, TUSB_EP_RX_OFFSET);
+
+       dma_remaining = TUSB_EP_CONFIG_XFR_SIZE(dma_remaining);
+       if (dma_remaining) {
+               dev_dbg(musb->controller, "Busy %s dma ch%i, not using: %08x\n",
+                       chdat->tx ? "tx" : "rx", chdat->ch,
+                       dma_remaining);
+               return false;
+       }
+
+       chdat->transfer_len = len & ~0x1f;
+
+       if (len < packet_sz)
+               chdat->transfer_packet_sz = chdat->transfer_len;
+       else
+               chdat->transfer_packet_sz = packet_sz;
+
+       if (tusb_dma->multichannel) {
+               ch = chdat->ch;
+               dmareq = chdat->dmareq;
+               sync_dev = chdat->sync_dev;
+       } else {
+               if (tusb_omap_use_shared_dmareq(chdat) != 0) {
+                       dev_dbg(musb->controller, "could not get dma for ep%i\n", chdat->epnum);
+                       return false;
+               }
+               if (tusb_dma->ch < 0) {
+                       /* REVISIT: This should get blocked earlier, happens
+                        * with MSC ErrorRecoveryTest
+                        */
+                       WARN_ON(1);
+                       return false;
+               }
+
+               ch = tusb_dma->ch;
+               dmareq = tusb_dma->dmareq;
+               sync_dev = tusb_dma->sync_dev;
+               omap_set_dma_callback(ch, tusb_omap_dma_cb, channel);
+       }
+
+       chdat->packet_sz = packet_sz;
+       chdat->len = len;
+       channel->actual_len = 0;
+       chdat->dma_addr = dma_addr;
+       channel->status = MUSB_DMA_STATUS_BUSY;
+
+       /* Since we're recycling dma areas, we need to clean or invalidate */
+       if (chdat->tx)
+               dma_map_single(dev, phys_to_virt(dma_addr), len,
+                               DMA_TO_DEVICE);
+       else
+               dma_map_single(dev, phys_to_virt(dma_addr), len,
+                               DMA_FROM_DEVICE);
+
+       /* Use 16-bit transfer if dma_addr is not 32-bit aligned */
+       if ((dma_addr & 0x3) == 0) {
+               dma_params.data_type = OMAP_DMA_DATA_TYPE_S32;
+               dma_params.elem_count = 8;              /* Elements in frame */
+       } else {
+               dma_params.data_type = OMAP_DMA_DATA_TYPE_S16;
+               dma_params.elem_count = 16;             /* Elements in frame */
+               fifo = hw_ep->fifo_async;
+       }
+
+       dma_params.frame_count  = chdat->transfer_len / 32; /* Burst sz frame */
+
+       dev_dbg(musb->controller, "ep%i %s dma ch%i dma: %08x len: %u(%u) packet_sz: %i(%i)\n",
+               chdat->epnum, chdat->tx ? "tx" : "rx",
+               ch, dma_addr, chdat->transfer_len, len,
+               chdat->transfer_packet_sz, packet_sz);
+
+       /*
+        * Prepare omap DMA for transfer
+        */
+       if (chdat->tx) {
+               dma_params.src_amode    = OMAP_DMA_AMODE_POST_INC;
+               dma_params.src_start    = (unsigned long)dma_addr;
+               dma_params.src_ei       = 0;
+               dma_params.src_fi       = 0;
+
+               dma_params.dst_amode    = OMAP_DMA_AMODE_DOUBLE_IDX;
+               dma_params.dst_start    = (unsigned long)fifo;
+               dma_params.dst_ei       = 1;
+               dma_params.dst_fi       = -31;  /* Loop 32 byte window */
+
+               dma_params.trigger      = sync_dev;
+               dma_params.sync_mode    = OMAP_DMA_SYNC_FRAME;
+               dma_params.src_or_dst_synch     = 0;    /* Dest sync */
+
+               src_burst = OMAP_DMA_DATA_BURST_16;     /* 16x32 read */
+               dst_burst = OMAP_DMA_DATA_BURST_8;      /* 8x32 write */
+       } else {
+               dma_params.src_amode    = OMAP_DMA_AMODE_DOUBLE_IDX;
+               dma_params.src_start    = (unsigned long)fifo;
+               dma_params.src_ei       = 1;
+               dma_params.src_fi       = -31;  /* Loop 32 byte window */
+
+               dma_params.dst_amode    = OMAP_DMA_AMODE_POST_INC;
+               dma_params.dst_start    = (unsigned long)dma_addr;
+               dma_params.dst_ei       = 0;
+               dma_params.dst_fi       = 0;
+
+               dma_params.trigger      = sync_dev;
+               dma_params.sync_mode    = OMAP_DMA_SYNC_FRAME;
+               dma_params.src_or_dst_synch     = 1;    /* Source sync */
+
+               src_burst = OMAP_DMA_DATA_BURST_8;      /* 8x32 read */
+               dst_burst = OMAP_DMA_DATA_BURST_16;     /* 16x32 write */
+       }
+
+       dev_dbg(musb->controller, "ep%i %s using %i-bit %s dma from 0x%08lx to 0x%08lx\n",
+               chdat->epnum, chdat->tx ? "tx" : "rx",
+               (dma_params.data_type == OMAP_DMA_DATA_TYPE_S32) ? 32 : 16,
+               ((dma_addr & 0x3) == 0) ? "sync" : "async",
+               dma_params.src_start, dma_params.dst_start);
+
+       omap_set_dma_params(ch, &dma_params);
+       omap_set_dma_src_burst_mode(ch, src_burst);
+       omap_set_dma_dest_burst_mode(ch, dst_burst);
+       omap_set_dma_write_mode(ch, OMAP_DMA_WRITE_LAST_NON_POSTED);
+
+       /*
+        * Prepare MUSB for DMA transfer
+        */
+       if (chdat->tx) {
+               musb_ep_select(mbase, chdat->epnum);
+               csr = musb_readw(hw_ep->regs, MUSB_TXCSR);
+               csr |= (MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB
+                       | MUSB_TXCSR_DMAMODE | MUSB_TXCSR_MODE);
+               csr &= ~MUSB_TXCSR_P_UNDERRUN;
+               musb_writew(hw_ep->regs, MUSB_TXCSR, csr);
+       } else {
+               musb_ep_select(mbase, chdat->epnum);
+               csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
+               csr |= MUSB_RXCSR_DMAENAB;
+               csr &= ~(MUSB_RXCSR_AUTOCLEAR | MUSB_RXCSR_DMAMODE);
+               musb_writew(hw_ep->regs, MUSB_RXCSR,
+                       csr | MUSB_RXCSR_P_WZC_BITS);
+       }
+
+       /*
+        * Start DMA transfer
+        */
+       omap_start_dma(ch);
+
+       if (chdat->tx) {
+               /* Send transfer_packet_sz packets at a time */
+               musb_writel(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET,
+                       chdat->transfer_packet_sz);
+
+               musb_writel(ep_conf, TUSB_EP_TX_OFFSET,
+                       TUSB_EP_CONFIG_XFR_SIZE(chdat->transfer_len));
+       } else {
+               /* Receive transfer_packet_sz packets at a time */
+               musb_writel(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET,
+                       chdat->transfer_packet_sz << 16);
+
+               musb_writel(ep_conf, TUSB_EP_RX_OFFSET,
+                       TUSB_EP_CONFIG_XFR_SIZE(chdat->transfer_len));
+       }
+
+       return true;
+}
+
+static int tusb_omap_dma_abort(struct dma_channel *channel)
+{
+       struct tusb_omap_dma_ch *chdat = to_chdat(channel);
+       struct tusb_omap_dma    *tusb_dma = chdat->tusb_dma;
+
+       if (!tusb_dma->multichannel) {
+               if (tusb_dma->ch >= 0) {
+                       omap_stop_dma(tusb_dma->ch);
+                       omap_free_dma(tusb_dma->ch);
+                       tusb_dma->ch = -1;
+               }
+
+               tusb_dma->dmareq = -1;
+               tusb_dma->sync_dev = -1;
+       }
+
+       channel->status = MUSB_DMA_STATUS_FREE;
+
+       return 0;
+}
+
+static inline int tusb_omap_dma_allocate_dmareq(struct tusb_omap_dma_ch *chdat)
+{
+       u32             reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
+       int             i, dmareq_nr = -1;
+
+       const int sync_dev[6] = {
+               OMAP24XX_DMA_EXT_DMAREQ0,
+               OMAP24XX_DMA_EXT_DMAREQ1,
+               OMAP242X_DMA_EXT_DMAREQ2,
+               OMAP242X_DMA_EXT_DMAREQ3,
+               OMAP242X_DMA_EXT_DMAREQ4,
+               OMAP242X_DMA_EXT_DMAREQ5,
+       };
+
+       for (i = 0; i < MAX_DMAREQ; i++) {
+               int cur = (reg & (0xf << (i * 5))) >> (i * 5);
+               if (cur == 0) {
+                       dmareq_nr = i;
+                       break;
+               }
+       }
+
+       if (dmareq_nr == -1)
+               return -EAGAIN;
+
+       reg |= (chdat->epnum << (dmareq_nr * 5));
+       if (chdat->tx)
+               reg |= ((1 << 4) << (dmareq_nr * 5));
+       musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
+
+       chdat->dmareq = dmareq_nr;
+       chdat->sync_dev = sync_dev[chdat->dmareq];
+
+       return 0;
+}
+
+static inline void tusb_omap_dma_free_dmareq(struct tusb_omap_dma_ch *chdat)
+{
+       u32 reg;
+
+       if (!chdat || chdat->dmareq < 0)
+               return;
+
+       reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
+       reg &= ~(0x1f << (chdat->dmareq * 5));
+       musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
+
+       chdat->dmareq = -1;
+       chdat->sync_dev = -1;
+}
+
+static struct dma_channel *dma_channel_pool[MAX_DMAREQ];
+
+static struct dma_channel *
+tusb_omap_dma_allocate(struct dma_controller *c,
+               struct musb_hw_ep *hw_ep,
+               u8 tx)
+{
+       int ret, i;
+       const char              *dev_name;
+       struct tusb_omap_dma    *tusb_dma;
+       struct musb             *musb;
+       void __iomem            *tbase;
+       struct dma_channel      *channel = NULL;
+       struct tusb_omap_dma_ch *chdat = NULL;
+       u32                     reg;
+
+       tusb_dma = container_of(c, struct tusb_omap_dma, controller);
+       musb = tusb_dma->musb;
+       tbase = musb->ctrl_base;
+
+       reg = musb_readl(tbase, TUSB_DMA_INT_MASK);
+       if (tx)
+               reg &= ~(1 << hw_ep->epnum);
+       else
+               reg &= ~(1 << (hw_ep->epnum + 15));
+       musb_writel(tbase, TUSB_DMA_INT_MASK, reg);
+
+       /* REVISIT: Why does dmareq5 not work? */
+       if (hw_ep->epnum == 0) {
+               dev_dbg(musb->controller, "Not allowing DMA for ep0 %s\n", tx ? "tx" : "rx");
+               return NULL;
+       }
+
+       for (i = 0; i < MAX_DMAREQ; i++) {
+               struct dma_channel *ch = dma_channel_pool[i];
+               if (ch->status == MUSB_DMA_STATUS_UNKNOWN) {
+                       ch->status = MUSB_DMA_STATUS_FREE;
+                       channel = ch;
+                       chdat = ch->private_data;
+                       break;
+               }
+       }
+
+       if (!channel)
+               return NULL;
+
+       if (tx) {
+               chdat->tx = 1;
+               dev_name = "TUSB transmit";
+       } else {
+               chdat->tx = 0;
+               dev_name = "TUSB receive";
+       }
+
+       chdat->musb = tusb_dma->musb;
+       chdat->tbase = tusb_dma->tbase;
+       chdat->hw_ep = hw_ep;
+       chdat->epnum = hw_ep->epnum;
+       chdat->dmareq = -1;
+       chdat->completed_len = 0;
+       chdat->tusb_dma = tusb_dma;
+
+       channel->max_len = 0x7fffffff;
+       channel->desired_mode = 0;
+       channel->actual_len = 0;
+
+       if (tusb_dma->multichannel) {
+               ret = tusb_omap_dma_allocate_dmareq(chdat);
+               if (ret != 0)
+                       goto free_dmareq;
+
+               ret = omap_request_dma(chdat->sync_dev, dev_name,
+                               tusb_omap_dma_cb, channel, &chdat->ch);
+               if (ret != 0)
+                       goto free_dmareq;
+       } else if (tusb_dma->ch == -1) {
+               tusb_dma->dmareq = 0;
+               tusb_dma->sync_dev = OMAP24XX_DMA_EXT_DMAREQ0;
+
+               /* Callback data gets set later in the shared dmareq case */
+               ret = omap_request_dma(tusb_dma->sync_dev, "TUSB shared",
+                               tusb_omap_dma_cb, NULL, &tusb_dma->ch);
+               if (ret != 0)
+                       goto free_dmareq;
+
+               chdat->dmareq = -1;
+               chdat->ch = -1;
+       }
+
+       dev_dbg(musb->controller, "ep%i %s dma: %s dma%i dmareq%i sync%i\n",
+               chdat->epnum,
+               chdat->tx ? "tx" : "rx",
+               chdat->ch >= 0 ? "dedicated" : "shared",
+               chdat->ch >= 0 ? chdat->ch : tusb_dma->ch,
+               chdat->dmareq >= 0 ? chdat->dmareq : tusb_dma->dmareq,
+               chdat->sync_dev >= 0 ? chdat->sync_dev : tusb_dma->sync_dev);
+
+       return channel;
+
+free_dmareq:
+       tusb_omap_dma_free_dmareq(chdat);
+
+       dev_dbg(musb->controller, "ep%i: Could not get a DMA channel\n", chdat->epnum);
+       channel->status = MUSB_DMA_STATUS_UNKNOWN;
+
+       return NULL;
+}
+
+static void tusb_omap_dma_release(struct dma_channel *channel)
+{
+       struct tusb_omap_dma_ch *chdat = to_chdat(channel);
+       struct musb             *musb = chdat->musb;
+       void __iomem            *tbase = musb->ctrl_base;
+       u32                     reg;
+
+       dev_dbg(musb->controller, "ep%i ch%i\n", chdat->epnum, chdat->ch);
+
+       reg = musb_readl(tbase, TUSB_DMA_INT_MASK);
+       if (chdat->tx)
+               reg |= (1 << chdat->epnum);
+       else
+               reg |= (1 << (chdat->epnum + 15));
+       musb_writel(tbase, TUSB_DMA_INT_MASK, reg);
+
+       reg = musb_readl(tbase, TUSB_DMA_INT_CLEAR);
+       if (chdat->tx)
+               reg |= (1 << chdat->epnum);
+       else
+               reg |= (1 << (chdat->epnum + 15));
+       musb_writel(tbase, TUSB_DMA_INT_CLEAR, reg);
+
+       channel->status = MUSB_DMA_STATUS_UNKNOWN;
+
+       if (chdat->ch >= 0) {
+               omap_stop_dma(chdat->ch);
+               omap_free_dma(chdat->ch);
+               chdat->ch = -1;
+       }
+
+       if (chdat->dmareq >= 0)
+               tusb_omap_dma_free_dmareq(chdat);
+
+       channel = NULL;
+}
+
+void dma_controller_destroy(struct dma_controller *c)
+{
+       struct tusb_omap_dma    *tusb_dma;
+       int                     i;
+
+       tusb_dma = container_of(c, struct tusb_omap_dma, controller);
+       for (i = 0; i < MAX_DMAREQ; i++) {
+               struct dma_channel *ch = dma_channel_pool[i];
+               if (ch) {
+                       kfree(ch->private_data);
+                       kfree(ch);
+               }
+       }
+
+       if (tusb_dma && !tusb_dma->multichannel && tusb_dma->ch >= 0)
+               omap_free_dma(tusb_dma->ch);
+
+       kfree(tusb_dma);
+}
+
+struct dma_controller *dma_controller_create(struct musb *musb, void __iomem *base)
+{
+       void __iomem            *tbase = musb->ctrl_base;
+       struct tusb_omap_dma    *tusb_dma;
+       int                     i;
+
+       /* REVISIT: Get dmareq lines used from board-*.c */
+
+       musb_writel(musb->ctrl_base, TUSB_DMA_INT_MASK, 0x7fffffff);
+       musb_writel(musb->ctrl_base, TUSB_DMA_EP_MAP, 0);
+
+       musb_writel(tbase, TUSB_DMA_REQ_CONF,
+               TUSB_DMA_REQ_CONF_BURST_SIZE(2)
+               | TUSB_DMA_REQ_CONF_DMA_REQ_EN(0x3f)
+               | TUSB_DMA_REQ_CONF_DMA_REQ_ASSER(2));
+
+       tusb_dma = kzalloc(sizeof(struct tusb_omap_dma), GFP_KERNEL);
+       if (!tusb_dma)
+               goto out;
+
+       tusb_dma->musb = musb;
+       tusb_dma->tbase = musb->ctrl_base;
+
+       tusb_dma->ch = -1;
+       tusb_dma->dmareq = -1;
+       tusb_dma->sync_dev = -1;
+
+       tusb_dma->controller.channel_alloc = tusb_omap_dma_allocate;
+       tusb_dma->controller.channel_release = tusb_omap_dma_release;
+       tusb_dma->controller.channel_program = tusb_omap_dma_program;
+       tusb_dma->controller.channel_abort = tusb_omap_dma_abort;
+
+       if (musb->tusb_revision >= TUSB_REV_30)
+               tusb_dma->multichannel = 1;
+
+       for (i = 0; i < MAX_DMAREQ; i++) {
+               struct dma_channel      *ch;
+               struct tusb_omap_dma_ch *chdat;
+
+               ch = kzalloc(sizeof(struct dma_channel), GFP_KERNEL);
+               if (!ch)
+                       goto cleanup;
+
+               dma_channel_pool[i] = ch;
+
+               chdat = kzalloc(sizeof(struct tusb_omap_dma_ch), GFP_KERNEL);
+               if (!chdat)
+                       goto cleanup;
+
+               ch->status = MUSB_DMA_STATUS_UNKNOWN;
+               ch->private_data = chdat;
+       }
+
+       return &tusb_dma->controller;
+
+cleanup:
+       dma_controller_destroy(&tusb_dma->controller);
+out:
+       return NULL;
+}