This commit was manufactured by cvs2svn to create branch 'vserver'.
[linux-2.6.git] / arch / arm / plat-omap / dma.c
diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
new file mode 100644 (file)
index 0000000..5dac423
--- /dev/null
@@ -0,0 +1,1405 @@
+/*
+ * linux/arch/arm/plat-omap/dma.c
+ *
+ * Copyright (C) 2003 Nokia Corporation
+ * Author: Juha Yrjölä <juha.yrjola@nokia.com>
+ * DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
+ * Graphics DMA and LCD DMA graphics tranformations
+ * by Imre Deak <imre.deak@nokia.com>
+ * OMAP2 support Copyright (C) 2004-2005 Texas Instruments, Inc.
+ * Merged to support both OMAP1 and OMAP2 by Tony Lindgren <tony@atomide.com>
+ * Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
+ *
+ * Support functions for the OMAP internal DMA channels.
+ *
+ * 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/init.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+
+#include <asm/system.h>
+#include <asm/irq.h>
+#include <asm/hardware.h>
+#include <asm/dma.h>
+#include <asm/io.h>
+
+#include <asm/arch/tc.h>
+
+#define DEBUG_PRINTS
+#undef DEBUG_PRINTS
+#ifdef DEBUG_PRINTS
+#define debug_printk(x) printk x
+#else
+#define        debug_printk(x)
+#endif
+
+#define OMAP_DMA_ACTIVE                0x01
+#define OMAP_DMA_CCR_EN                (1 << 7)
+
+#define OMAP_FUNC_MUX_ARM_BASE (0xfffe1000 + 0xec)
+
+static int enable_1510_mode = 0;
+
+struct omap_dma_lch {
+       int next_lch;
+       int dev_id;
+       u16 saved_csr;
+       u16 enabled_irqs;
+       const char *dev_name;
+       void (* callback)(int lch, u16 ch_status, void *data);
+       void *data;
+       long flags;
+};
+
+static int dma_chan_count;
+
+static spinlock_t dma_chan_lock;
+static struct omap_dma_lch dma_chan[OMAP_LOGICAL_DMA_CH_COUNT];
+
+static const u8 omap1_dma_irq[OMAP_LOGICAL_DMA_CH_COUNT] = {
+       INT_DMA_CH0_6, INT_DMA_CH1_7, INT_DMA_CH2_8, INT_DMA_CH3,
+       INT_DMA_CH4, INT_DMA_CH5, INT_1610_DMA_CH6, INT_1610_DMA_CH7,
+       INT_1610_DMA_CH8, INT_1610_DMA_CH9, INT_1610_DMA_CH10,
+       INT_1610_DMA_CH11, INT_1610_DMA_CH12, INT_1610_DMA_CH13,
+       INT_1610_DMA_CH14, INT_1610_DMA_CH15, INT_DMA_LCD
+};
+
+#define REVISIT_24XX()         printk(KERN_ERR "FIXME: no %s on 24xx\n", \
+                                               __FUNCTION__);
+
+#ifdef CONFIG_ARCH_OMAP15XX
+/* Returns 1 if the DMA module is in OMAP1510-compatible mode, 0 otherwise */
+int omap_dma_in_1510_mode(void)
+{
+       return enable_1510_mode;
+}
+#else
+#define omap_dma_in_1510_mode()                0
+#endif
+
+#ifdef CONFIG_ARCH_OMAP1
+static inline int get_gdma_dev(int req)
+{
+       u32 reg = OMAP_FUNC_MUX_ARM_BASE + ((req - 1) / 5) * 4;
+       int shift = ((req - 1) % 5) * 6;
+
+       return ((omap_readl(reg) >> shift) & 0x3f) + 1;
+}
+
+static inline void set_gdma_dev(int req, int dev)
+{
+       u32 reg = OMAP_FUNC_MUX_ARM_BASE + ((req - 1) / 5) * 4;
+       int shift = ((req - 1) % 5) * 6;
+       u32 l;
+
+       l = omap_readl(reg);
+       l &= ~(0x3f << shift);
+       l |= (dev - 1) << shift;
+       omap_writel(l, reg);
+}
+#else
+#define set_gdma_dev(req, dev) do {} while (0)
+#endif
+
+static void clear_lch_regs(int lch)
+{
+       int i;
+       u32 lch_base = OMAP_DMA_BASE + lch * 0x40;
+
+       for (i = 0; i < 0x2c; i += 2)
+               omap_writew(0, lch_base + i);
+}
+
+void omap_set_dma_priority(int dst_port, int priority)
+{
+       unsigned long reg;
+       u32 l;
+
+       switch (dst_port) {
+       case OMAP_DMA_PORT_OCP_T1:      /* FFFECC00 */
+               reg = OMAP_TC_OCPT1_PRIOR;
+               break;
+       case OMAP_DMA_PORT_OCP_T2:      /* FFFECCD0 */
+               reg = OMAP_TC_OCPT2_PRIOR;
+               break;
+       case OMAP_DMA_PORT_EMIFF:       /* FFFECC08 */
+               reg = OMAP_TC_EMIFF_PRIOR;
+               break;
+       case OMAP_DMA_PORT_EMIFS:       /* FFFECC04 */
+               reg = OMAP_TC_EMIFS_PRIOR;
+               break;
+       default:
+               BUG();
+               return;
+       }
+       l = omap_readl(reg);
+       l &= ~(0xf << 8);
+       l |= (priority & 0xf) << 8;
+       omap_writel(l, reg);
+}
+
+void omap_set_dma_transfer_params(int lch, int data_type, int elem_count,
+                                 int frame_count, int sync_mode,
+                                 int dma_trigger, int src_or_dst_synch)
+{
+       OMAP_DMA_CSDP_REG(lch) &= ~0x03;
+       OMAP_DMA_CSDP_REG(lch) |= data_type;
+
+       if (cpu_class_is_omap1()) {
+               OMAP_DMA_CCR_REG(lch) &= ~(1 << 5);
+               if (sync_mode == OMAP_DMA_SYNC_FRAME)
+                       OMAP_DMA_CCR_REG(lch) |= 1 << 5;
+
+               OMAP1_DMA_CCR2_REG(lch) &= ~(1 << 2);
+               if (sync_mode == OMAP_DMA_SYNC_BLOCK)
+                       OMAP1_DMA_CCR2_REG(lch) |= 1 << 2;
+       }
+
+       if (cpu_is_omap24xx() && dma_trigger) {
+               u32 val = OMAP_DMA_CCR_REG(lch);
+
+               if (dma_trigger > 63)
+                       val |= 1 << 20;
+               if (dma_trigger > 31)
+                       val |= 1 << 19;
+
+               val |= (dma_trigger & 0x1f);
+
+               if (sync_mode & OMAP_DMA_SYNC_FRAME)
+                       val |= 1 << 5;
+
+               if (sync_mode & OMAP_DMA_SYNC_BLOCK)
+                       val |= 1 << 18;
+
+               if (src_or_dst_synch)
+                       val |= 1 << 24;         /* source synch */
+               else
+                       val &= ~(1 << 24);      /* dest synch */
+
+               OMAP_DMA_CCR_REG(lch) = val;
+       }
+
+       OMAP_DMA_CEN_REG(lch) = elem_count;
+       OMAP_DMA_CFN_REG(lch) = frame_count;
+}
+
+void omap_set_dma_color_mode(int lch, enum omap_dma_color_mode mode, u32 color)
+{
+       u16 w;
+
+       BUG_ON(omap_dma_in_1510_mode());
+
+       if (cpu_is_omap24xx()) {
+               REVISIT_24XX();
+               return;
+       }
+
+       w = OMAP1_DMA_CCR2_REG(lch) & ~0x03;
+       switch (mode) {
+       case OMAP_DMA_CONSTANT_FILL:
+               w |= 0x01;
+               break;
+       case OMAP_DMA_TRANSPARENT_COPY:
+               w |= 0x02;
+               break;
+       case OMAP_DMA_COLOR_DIS:
+               break;
+       default:
+               BUG();
+       }
+       OMAP1_DMA_CCR2_REG(lch) = w;
+
+       w = OMAP1_DMA_LCH_CTRL_REG(lch) & ~0x0f;
+       /* Default is channel type 2D */
+       if (mode) {
+               OMAP1_DMA_COLOR_L_REG(lch) = (u16)color;
+               OMAP1_DMA_COLOR_U_REG(lch) = (u16)(color >> 16);
+               w |= 1;         /* Channel type G */
+       }
+       OMAP1_DMA_LCH_CTRL_REG(lch) = w;
+}
+
+/* Note that src_port is only for omap1 */
+void omap_set_dma_src_params(int lch, int src_port, int src_amode,
+                            unsigned long src_start,
+                            int src_ei, int src_fi)
+{
+       if (cpu_class_is_omap1()) {
+               OMAP_DMA_CSDP_REG(lch) &= ~(0x1f << 2);
+               OMAP_DMA_CSDP_REG(lch) |= src_port << 2;
+       }
+
+       OMAP_DMA_CCR_REG(lch) &= ~(0x03 << 12);
+       OMAP_DMA_CCR_REG(lch) |= src_amode << 12;
+
+       if (cpu_class_is_omap1()) {
+               OMAP1_DMA_CSSA_U_REG(lch) = src_start >> 16;
+               OMAP1_DMA_CSSA_L_REG(lch) = src_start;
+       }
+
+       if (cpu_is_omap24xx())
+               OMAP2_DMA_CSSA_REG(lch) = src_start;
+
+       OMAP_DMA_CSEI_REG(lch) = src_ei;
+       OMAP_DMA_CSFI_REG(lch) = src_fi;
+}
+
+void omap_set_dma_params(int lch, struct omap_dma_channel_params * params)
+{
+       omap_set_dma_transfer_params(lch, params->data_type,
+                                    params->elem_count, params->frame_count,
+                                    params->sync_mode, params->trigger,
+                                    params->src_or_dst_synch);
+       omap_set_dma_src_params(lch, params->src_port,
+                               params->src_amode, params->src_start,
+                               params->src_ei, params->src_fi);
+
+       omap_set_dma_dest_params(lch, params->dst_port,
+                                params->dst_amode, params->dst_start,
+                                params->dst_ei, params->dst_fi);
+}
+
+void omap_set_dma_src_index(int lch, int eidx, int fidx)
+{
+       if (cpu_is_omap24xx()) {
+               REVISIT_24XX();
+               return;
+       }
+       OMAP_DMA_CSEI_REG(lch) = eidx;
+       OMAP_DMA_CSFI_REG(lch) = fidx;
+}
+
+void omap_set_dma_src_data_pack(int lch, int enable)
+{
+       OMAP_DMA_CSDP_REG(lch) &= ~(1 << 6);
+       if (enable)
+               OMAP_DMA_CSDP_REG(lch) |= (1 << 6);
+}
+
+void omap_set_dma_src_burst_mode(int lch, enum omap_dma_burst_mode burst_mode)
+{
+       OMAP_DMA_CSDP_REG(lch) &= ~(0x03 << 7);
+
+       switch (burst_mode) {
+       case OMAP_DMA_DATA_BURST_DIS:
+               break;
+       case OMAP_DMA_DATA_BURST_4:
+               OMAP_DMA_CSDP_REG(lch) |= (0x02 << 7);
+               break;
+       case OMAP_DMA_DATA_BURST_8:
+               /* not supported by current hardware
+                * w |= (0x03 << 7);
+                * fall through
+                */
+       default:
+               BUG();
+       }
+}
+
+/* Note that dest_port is only for OMAP1 */
+void omap_set_dma_dest_params(int lch, int dest_port, int dest_amode,
+                             unsigned long dest_start,
+                             int dst_ei, int dst_fi)
+{
+       if (cpu_class_is_omap1()) {
+               OMAP_DMA_CSDP_REG(lch) &= ~(0x1f << 9);
+               OMAP_DMA_CSDP_REG(lch) |= dest_port << 9;
+       }
+
+       OMAP_DMA_CCR_REG(lch) &= ~(0x03 << 14);
+       OMAP_DMA_CCR_REG(lch) |= dest_amode << 14;
+
+       if (cpu_class_is_omap1()) {
+               OMAP1_DMA_CDSA_U_REG(lch) = dest_start >> 16;
+               OMAP1_DMA_CDSA_L_REG(lch) = dest_start;
+       }
+
+       if (cpu_is_omap24xx())
+               OMAP2_DMA_CDSA_REG(lch) = dest_start;
+
+       OMAP_DMA_CDEI_REG(lch) = dst_ei;
+       OMAP_DMA_CDFI_REG(lch) = dst_fi;
+}
+
+void omap_set_dma_dest_index(int lch, int eidx, int fidx)
+{
+       if (cpu_is_omap24xx()) {
+               REVISIT_24XX();
+               return;
+       }
+       OMAP_DMA_CDEI_REG(lch) = eidx;
+       OMAP_DMA_CDFI_REG(lch) = fidx;
+}
+
+void omap_set_dma_dest_data_pack(int lch, int enable)
+{
+       OMAP_DMA_CSDP_REG(lch) &= ~(1 << 13);
+       if (enable)
+               OMAP_DMA_CSDP_REG(lch) |= 1 << 13;
+}
+
+void omap_set_dma_dest_burst_mode(int lch, enum omap_dma_burst_mode burst_mode)
+{
+       OMAP_DMA_CSDP_REG(lch) &= ~(0x03 << 14);
+
+       switch (burst_mode) {
+       case OMAP_DMA_DATA_BURST_DIS:
+               break;
+       case OMAP_DMA_DATA_BURST_4:
+               OMAP_DMA_CSDP_REG(lch) |= (0x02 << 14);
+               break;
+       case OMAP_DMA_DATA_BURST_8:
+               OMAP_DMA_CSDP_REG(lch) |= (0x03 << 14);
+               break;
+       default:
+               printk(KERN_ERR "Invalid DMA burst mode\n");
+               BUG();
+               return;
+       }
+}
+
+static inline void omap_enable_channel_irq(int lch)
+{
+       u32 status;
+
+       /* Read CSR to make sure it's cleared. */
+       status = OMAP_DMA_CSR_REG(lch);
+
+       /* Enable some nice interrupts. */
+       OMAP_DMA_CICR_REG(lch) = dma_chan[lch].enabled_irqs;
+
+       dma_chan[lch].flags |= OMAP_DMA_ACTIVE;
+}
+
+static void omap_disable_channel_irq(int lch)
+{
+       if (cpu_is_omap24xx())
+               OMAP_DMA_CICR_REG(lch) = 0;
+}
+
+void omap_enable_dma_irq(int lch, u16 bits)
+{
+       dma_chan[lch].enabled_irqs |= bits;
+}
+
+void omap_disable_dma_irq(int lch, u16 bits)
+{
+       dma_chan[lch].enabled_irqs &= ~bits;
+}
+
+static inline void enable_lnk(int lch)
+{
+       if (cpu_class_is_omap1())
+               OMAP_DMA_CLNK_CTRL_REG(lch) &= ~(1 << 14);
+
+       /* Set the ENABLE_LNK bits */
+       if (dma_chan[lch].next_lch != -1)
+               OMAP_DMA_CLNK_CTRL_REG(lch) =
+                       dma_chan[lch].next_lch | (1 << 15);
+}
+
+static inline void disable_lnk(int lch)
+{
+       /* Disable interrupts */
+       if (cpu_class_is_omap1()) {
+               OMAP_DMA_CICR_REG(lch) = 0;
+               /* Set the STOP_LNK bit */
+               OMAP_DMA_CLNK_CTRL_REG(lch) |= 1 << 14;
+       }
+
+       if (cpu_is_omap24xx()) {
+               omap_disable_channel_irq(lch);
+               /* Clear the ENABLE_LNK bit */
+               OMAP_DMA_CLNK_CTRL_REG(lch) &= ~(1 << 15);
+       }
+
+       dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE;
+}
+
+static inline void omap2_enable_irq_lch(int lch)
+{
+       u32 val;
+
+       if (!cpu_is_omap24xx())
+               return;
+
+       val = omap_readl(OMAP_DMA4_IRQENABLE_L0);
+       val |= 1 << lch;
+       omap_writel(val, OMAP_DMA4_IRQENABLE_L0);
+}
+
+int omap_request_dma(int dev_id, const char *dev_name,
+                    void (* callback)(int lch, u16 ch_status, void *data),
+                    void *data, int *dma_ch_out)
+{
+       int ch, free_ch = -1;
+       unsigned long flags;
+       struct omap_dma_lch *chan;
+
+       spin_lock_irqsave(&dma_chan_lock, flags);
+       for (ch = 0; ch < dma_chan_count; ch++) {
+               if (free_ch == -1 && dma_chan[ch].dev_id == -1) {
+                       free_ch = ch;
+                       if (dev_id == 0)
+                               break;
+               }
+       }
+       if (free_ch == -1) {
+               spin_unlock_irqrestore(&dma_chan_lock, flags);
+               return -EBUSY;
+       }
+       chan = dma_chan + free_ch;
+       chan->dev_id = dev_id;
+
+       if (cpu_class_is_omap1())
+               clear_lch_regs(free_ch);
+
+       if (cpu_is_omap24xx())
+               omap_clear_dma(free_ch);
+
+       spin_unlock_irqrestore(&dma_chan_lock, flags);
+
+       chan->dev_name = dev_name;
+       chan->callback = callback;
+       chan->data = data;
+       chan->enabled_irqs = OMAP_DMA_TOUT_IRQ | OMAP_DMA_DROP_IRQ |
+                               OMAP_DMA_BLOCK_IRQ;
+
+       if (cpu_is_omap24xx())
+               chan->enabled_irqs |= OMAP2_DMA_TRANS_ERR_IRQ;
+
+       if (cpu_is_omap16xx()) {
+               /* If the sync device is set, configure it dynamically. */
+               if (dev_id != 0) {
+                       set_gdma_dev(free_ch + 1, dev_id);
+                       dev_id = free_ch + 1;
+               }
+               /* Disable the 1510 compatibility mode and set the sync device
+                * id. */
+               OMAP_DMA_CCR_REG(free_ch) = dev_id | (1 << 10);
+       } else if (cpu_is_omap730() || cpu_is_omap15xx()) {
+               OMAP_DMA_CCR_REG(free_ch) = dev_id;
+       }
+
+       if (cpu_is_omap24xx()) {
+               omap2_enable_irq_lch(free_ch);
+
+               omap_enable_channel_irq(free_ch);
+               /* Clear the CSR register and IRQ status register */
+               OMAP_DMA_CSR_REG(free_ch) = 0x0;
+               omap_writel(~0x0, OMAP_DMA4_IRQSTATUS_L0);
+       }
+
+       *dma_ch_out = free_ch;
+
+       return 0;
+}
+
+void omap_free_dma(int lch)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&dma_chan_lock, flags);
+       if (dma_chan[lch].dev_id == -1) {
+               printk("omap_dma: trying to free nonallocated DMA channel %d\n",
+                      lch);
+               spin_unlock_irqrestore(&dma_chan_lock, flags);
+               return;
+       }
+       dma_chan[lch].dev_id = -1;
+       dma_chan[lch].next_lch = -1;
+       dma_chan[lch].callback = NULL;
+       spin_unlock_irqrestore(&dma_chan_lock, flags);
+
+       if (cpu_class_is_omap1()) {
+               /* Disable all DMA interrupts for the channel. */
+               OMAP_DMA_CICR_REG(lch) = 0;
+               /* Make sure the DMA transfer is stopped. */
+               OMAP_DMA_CCR_REG(lch) = 0;
+       }
+
+       if (cpu_is_omap24xx()) {
+               u32 val;
+               /* Disable interrupts */
+               val = omap_readl(OMAP_DMA4_IRQENABLE_L0);
+               val &= ~(1 << lch);
+               omap_writel(val, OMAP_DMA4_IRQENABLE_L0);
+
+               /* Clear the CSR register and IRQ status register */
+               OMAP_DMA_CSR_REG(lch) = 0x0;
+
+               val = omap_readl(OMAP_DMA4_IRQSTATUS_L0);
+               val |= 1 << lch;
+               omap_writel(val, OMAP_DMA4_IRQSTATUS_L0);
+
+               /* Disable all DMA interrupts for the channel. */
+               OMAP_DMA_CICR_REG(lch) = 0;
+
+               /* Make sure the DMA transfer is stopped. */
+               OMAP_DMA_CCR_REG(lch) = 0;
+               omap_clear_dma(lch);
+       }
+}
+
+/*
+ * Clears any DMA state so the DMA engine is ready to restart with new buffers
+ * through omap_start_dma(). Any buffers in flight are discarded.
+ */
+void omap_clear_dma(int lch)
+{
+       unsigned long flags;
+
+       local_irq_save(flags);
+
+       if (cpu_class_is_omap1()) {
+               int status;
+               OMAP_DMA_CCR_REG(lch) &= ~OMAP_DMA_CCR_EN;
+
+               /* Clear pending interrupts */
+               status = OMAP_DMA_CSR_REG(lch);
+       }
+
+       if (cpu_is_omap24xx()) {
+               int i;
+               u32 lch_base = OMAP24XX_DMA_BASE + lch * 0x60 + 0x80;
+               for (i = 0; i < 0x44; i += 4)
+                       omap_writel(0, lch_base + i);
+       }
+
+       local_irq_restore(flags);
+}
+
+void omap_start_dma(int lch)
+{
+       if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) {
+               int next_lch, cur_lch;
+               char dma_chan_link_map[OMAP_LOGICAL_DMA_CH_COUNT];
+
+               dma_chan_link_map[lch] = 1;
+               /* Set the link register of the first channel */
+               enable_lnk(lch);
+
+               memset(dma_chan_link_map, 0, sizeof(dma_chan_link_map));
+               cur_lch = dma_chan[lch].next_lch;
+               do {
+                       next_lch = dma_chan[cur_lch].next_lch;
+
+                       /* The loop case: we've been here already */
+                       if (dma_chan_link_map[cur_lch])
+                               break;
+                       /* Mark the current channel */
+                       dma_chan_link_map[cur_lch] = 1;
+
+                       enable_lnk(cur_lch);
+                       omap_enable_channel_irq(cur_lch);
+
+                       cur_lch = next_lch;
+               } while (next_lch != -1);
+       } else if (cpu_is_omap24xx()) {
+               /* Errata: Need to write lch even if not using chaining */
+               OMAP_DMA_CLNK_CTRL_REG(lch) = lch;
+       }
+
+       omap_enable_channel_irq(lch);
+
+       /* Errata: On ES2.0 BUFFERING disable must be set.
+        * This will always fail on ES1.0 */
+       if (cpu_is_omap24xx()) {
+               OMAP_DMA_CCR_REG(lch) |= OMAP_DMA_CCR_EN;
+       }
+
+       OMAP_DMA_CCR_REG(lch) |= OMAP_DMA_CCR_EN;
+
+       dma_chan[lch].flags |= OMAP_DMA_ACTIVE;
+}
+
+void omap_stop_dma(int lch)
+{
+       if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) {
+               int next_lch, cur_lch = lch;
+               char dma_chan_link_map[OMAP_LOGICAL_DMA_CH_COUNT];
+
+               memset(dma_chan_link_map, 0, sizeof(dma_chan_link_map));
+               do {
+                       /* The loop case: we've been here already */
+                       if (dma_chan_link_map[cur_lch])
+                               break;
+                       /* Mark the current channel */
+                       dma_chan_link_map[cur_lch] = 1;
+
+                       disable_lnk(cur_lch);
+
+                       next_lch = dma_chan[cur_lch].next_lch;
+                       cur_lch = next_lch;
+               } while (next_lch != -1);
+
+               return;
+       }
+
+       /* Disable all interrupts on the channel */
+       if (cpu_class_is_omap1())
+               OMAP_DMA_CICR_REG(lch) = 0;
+
+       OMAP_DMA_CCR_REG(lch) &= ~OMAP_DMA_CCR_EN;
+       dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE;
+}
+
+/*
+ * Returns current physical source address for the given DMA channel.
+ * If the channel is running the caller must disable interrupts prior calling
+ * this function and process the returned value before re-enabling interrupt to
+ * prevent races with the interrupt handler. Note that in continuous mode there
+ * is a chance for CSSA_L register overflow inbetween the two reads resulting
+ * in incorrect return value.
+ */
+dma_addr_t omap_get_dma_src_pos(int lch)
+{
+       dma_addr_t offset;
+
+       if (cpu_class_is_omap1())
+               offset = (dma_addr_t) (OMAP1_DMA_CSSA_L_REG(lch) |
+                                      (OMAP1_DMA_CSSA_U_REG(lch) << 16));
+
+       if (cpu_is_omap24xx())
+               offset = OMAP_DMA_CSAC_REG(lch);
+
+       return offset;
+}
+
+/*
+ * Returns current physical destination address for the given DMA channel.
+ * If the channel is running the caller must disable interrupts prior calling
+ * this function and process the returned value before re-enabling interrupt to
+ * prevent races with the interrupt handler. Note that in continuous mode there
+ * is a chance for CDSA_L register overflow inbetween the two reads resulting
+ * in incorrect return value.
+ */
+dma_addr_t omap_get_dma_dst_pos(int lch)
+{
+       dma_addr_t offset;
+
+       if (cpu_class_is_omap1())
+               offset = (dma_addr_t) (OMAP1_DMA_CDSA_L_REG(lch) |
+                                      (OMAP1_DMA_CDSA_U_REG(lch) << 16));
+
+       if (cpu_is_omap24xx())
+               offset = OMAP2_DMA_CDSA_REG(lch);
+
+       return offset;
+}
+
+/*
+ * Returns current source transfer counting for the given DMA channel.
+ * Can be used to monitor the progress of a transfer inside a block.
+ * It must be called with disabled interrupts.
+ */
+int omap_get_dma_src_addr_counter(int lch)
+{
+       return (dma_addr_t) OMAP_DMA_CSAC_REG(lch);
+}
+
+int omap_dma_running(void)
+{
+       int lch;
+
+       /* Check if LCD DMA is running */
+       if (cpu_is_omap16xx())
+               if (omap_readw(OMAP1610_DMA_LCD_CCR) & OMAP_DMA_CCR_EN)
+                       return 1;
+
+       for (lch = 0; lch < dma_chan_count; lch++)
+               if (OMAP_DMA_CCR_REG(lch) & OMAP_DMA_CCR_EN)
+                       return 1;
+
+       return 0;
+}
+
+/*
+ * lch_queue DMA will start right after lch_head one is finished.
+ * For this DMA link to start, you still need to start (see omap_start_dma)
+ * the first one. That will fire up the entire queue.
+ */
+void omap_dma_link_lch (int lch_head, int lch_queue)
+{
+       if (omap_dma_in_1510_mode()) {
+               printk(KERN_ERR "DMA linking is not supported in 1510 mode\n");
+               BUG();
+               return;
+       }
+
+       if ((dma_chan[lch_head].dev_id == -1) ||
+           (dma_chan[lch_queue].dev_id == -1)) {
+               printk(KERN_ERR "omap_dma: trying to link "
+                      "non requested channels\n");
+               dump_stack();
+       }
+
+       dma_chan[lch_head].next_lch = lch_queue;
+}
+
+/*
+ * Once the DMA queue is stopped, we can destroy it.
+ */
+void omap_dma_unlink_lch (int lch_head, int lch_queue)
+{
+       if (omap_dma_in_1510_mode()) {
+               printk(KERN_ERR "DMA linking is not supported in 1510 mode\n");
+               BUG();
+               return;
+       }
+
+       if (dma_chan[lch_head].next_lch != lch_queue ||
+           dma_chan[lch_head].next_lch == -1) {
+               printk(KERN_ERR "omap_dma: trying to unlink "
+                      "non linked channels\n");
+               dump_stack();
+       }
+
+
+       if ((dma_chan[lch_head].flags & OMAP_DMA_ACTIVE) ||
+           (dma_chan[lch_head].flags & OMAP_DMA_ACTIVE)) {
+               printk(KERN_ERR "omap_dma: You need to stop the DMA channels "
+                      "before unlinking\n");
+               dump_stack();
+       }
+
+       dma_chan[lch_head].next_lch = -1;
+}
+
+/*----------------------------------------------------------------------------*/
+
+#ifdef CONFIG_ARCH_OMAP1
+
+static int omap1_dma_handle_ch(int ch)
+{
+       u16 csr;
+
+       if (enable_1510_mode && ch >= 6) {
+               csr = dma_chan[ch].saved_csr;
+               dma_chan[ch].saved_csr = 0;
+       } else
+               csr = OMAP_DMA_CSR_REG(ch);
+       if (enable_1510_mode && ch <= 2 && (csr >> 7) != 0) {
+               dma_chan[ch + 6].saved_csr = csr >> 7;
+               csr &= 0x7f;
+       }
+       if ((csr & 0x3f) == 0)
+               return 0;
+       if (unlikely(dma_chan[ch].dev_id == -1)) {
+               printk(KERN_WARNING "Spurious interrupt from DMA channel "
+                      "%d (CSR %04x)\n", ch, csr);
+               return 0;
+       }
+       if (unlikely(csr & OMAP_DMA_TOUT_IRQ))
+               printk(KERN_WARNING "DMA timeout with device %d\n",
+                      dma_chan[ch].dev_id);
+       if (unlikely(csr & OMAP_DMA_DROP_IRQ))
+               printk(KERN_WARNING "DMA synchronization event drop occurred "
+                      "with device %d\n", dma_chan[ch].dev_id);
+       if (likely(csr & OMAP_DMA_BLOCK_IRQ))
+               dma_chan[ch].flags &= ~OMAP_DMA_ACTIVE;
+       if (likely(dma_chan[ch].callback != NULL))
+               dma_chan[ch].callback(ch, csr, dma_chan[ch].data);
+       return 1;
+}
+
+static irqreturn_t omap1_dma_irq_handler(int irq, void *dev_id,
+                                        struct pt_regs *regs)
+{
+       int ch = ((int) dev_id) - 1;
+       int handled = 0;
+
+       for (;;) {
+               int handled_now = 0;
+
+               handled_now += omap1_dma_handle_ch(ch);
+               if (enable_1510_mode && dma_chan[ch + 6].saved_csr)
+                       handled_now += omap1_dma_handle_ch(ch + 6);
+               if (!handled_now)
+                       break;
+               handled += handled_now;
+       }
+
+       return handled ? IRQ_HANDLED : IRQ_NONE;
+}
+
+#else
+#define omap1_dma_irq_handler  NULL
+#endif
+
+#ifdef CONFIG_ARCH_OMAP2
+
+static int omap2_dma_handle_ch(int ch)
+{
+       u32 status = OMAP_DMA_CSR_REG(ch);
+       u32 val;
+
+       if (!status)
+               return 0;
+       if (unlikely(dma_chan[ch].dev_id == -1))
+               return 0;
+       /* REVISIT: According to 24xx TRM, there's no TOUT_IE */
+       if (unlikely(status & OMAP_DMA_TOUT_IRQ))
+               printk(KERN_INFO "DMA timeout with device %d\n",
+                      dma_chan[ch].dev_id);
+       if (unlikely(status & OMAP_DMA_DROP_IRQ))
+               printk(KERN_INFO
+                      "DMA synchronization event drop occurred with device "
+                      "%d\n", dma_chan[ch].dev_id);
+
+       if (unlikely(status & OMAP2_DMA_TRANS_ERR_IRQ))
+               printk(KERN_INFO "DMA transaction error with device %d\n",
+                      dma_chan[ch].dev_id);
+
+       OMAP_DMA_CSR_REG(ch) = 0x20;
+
+       val = omap_readl(OMAP_DMA4_IRQSTATUS_L0);
+       /* ch in this function is from 0-31 while in register it is 1-32 */
+       val = 1 << (ch);
+       omap_writel(val, OMAP_DMA4_IRQSTATUS_L0);
+
+       if (likely(dma_chan[ch].callback != NULL))
+               dma_chan[ch].callback(ch, status, dma_chan[ch].data);
+
+       return 0;
+}
+
+/* STATUS register count is from 1-32 while our is 0-31 */
+static irqreturn_t omap2_dma_irq_handler(int irq, void *dev_id,
+                                        struct pt_regs *regs)
+{
+       u32 val;
+       int i;
+
+       val = omap_readl(OMAP_DMA4_IRQSTATUS_L0);
+
+       for (i = 1; i <= OMAP_LOGICAL_DMA_CH_COUNT; i++) {
+               int active = val & (1 << (i - 1));
+               if (active)
+                       omap2_dma_handle_ch(i - 1);
+       }
+
+       return IRQ_HANDLED;
+}
+
+static struct irqaction omap24xx_dma_irq = {
+       .name = "DMA",
+       .handler = omap2_dma_irq_handler,
+       .flags = SA_INTERRUPT
+};
+
+#else
+static struct irqaction omap24xx_dma_irq;
+#endif
+
+/*----------------------------------------------------------------------------*/
+
+static struct lcd_dma_info {
+       spinlock_t lock;
+       int reserved;
+       void (* callback)(u16 status, void *data);
+       void *cb_data;
+
+       int active;
+       unsigned long addr, size;
+       int rotate, data_type, xres, yres;
+       int vxres;
+       int mirror;
+       int xscale, yscale;
+       int ext_ctrl;
+       int src_port;
+       int single_transfer;
+} lcd_dma;
+
+void omap_set_lcd_dma_b1(unsigned long addr, u16 fb_xres, u16 fb_yres,
+                        int data_type)
+{
+       lcd_dma.addr = addr;
+       lcd_dma.data_type = data_type;
+       lcd_dma.xres = fb_xres;
+       lcd_dma.yres = fb_yres;
+}
+
+void omap_set_lcd_dma_src_port(int port)
+{
+       lcd_dma.src_port = port;
+}
+
+void omap_set_lcd_dma_ext_controller(int external)
+{
+       lcd_dma.ext_ctrl = external;
+}
+
+void omap_set_lcd_dma_single_transfer(int single)
+{
+       lcd_dma.single_transfer = single;
+}
+
+
+void omap_set_lcd_dma_b1_rotation(int rotate)
+{
+       if (omap_dma_in_1510_mode()) {
+               printk(KERN_ERR "DMA rotation is not supported in 1510 mode\n");
+               BUG();
+               return;
+       }
+       lcd_dma.rotate = rotate;
+}
+
+void omap_set_lcd_dma_b1_mirror(int mirror)
+{
+       if (omap_dma_in_1510_mode()) {
+               printk(KERN_ERR "DMA mirror is not supported in 1510 mode\n");
+               BUG();
+       }
+       lcd_dma.mirror = mirror;
+}
+
+void omap_set_lcd_dma_b1_vxres(unsigned long vxres)
+{
+       if (omap_dma_in_1510_mode()) {
+               printk(KERN_ERR "DMA virtual resulotion is not supported "
+                               "in 1510 mode\n");
+               BUG();
+       }
+       lcd_dma.vxres = vxres;
+}
+
+void omap_set_lcd_dma_b1_scale(unsigned int xscale, unsigned int yscale)
+{
+       if (omap_dma_in_1510_mode()) {
+               printk(KERN_ERR "DMA scale is not supported in 1510 mode\n");
+               BUG();
+       }
+       lcd_dma.xscale = xscale;
+       lcd_dma.yscale = yscale;
+}
+
+static void set_b1_regs(void)
+{
+       unsigned long top, bottom;
+       int es;
+       u16 w;
+       unsigned long en, fn;
+       long ei, fi;
+       unsigned long vxres;
+       unsigned int xscale, yscale;
+
+       switch (lcd_dma.data_type) {
+       case OMAP_DMA_DATA_TYPE_S8:
+               es = 1;
+               break;
+       case OMAP_DMA_DATA_TYPE_S16:
+               es = 2;
+               break;
+       case OMAP_DMA_DATA_TYPE_S32:
+               es = 4;
+               break;
+       default:
+               BUG();
+               return;
+       }
+
+       vxres = lcd_dma.vxres ? lcd_dma.vxres : lcd_dma.xres;
+       xscale = lcd_dma.xscale ? lcd_dma.xscale : 1;
+       yscale = lcd_dma.yscale ? lcd_dma.yscale : 1;
+       BUG_ON(vxres < lcd_dma.xres);
+#define PIXADDR(x,y) (lcd_dma.addr + ((y) * vxres * yscale + (x) * xscale) * es)
+#define PIXSTEP(sx, sy, dx, dy) (PIXADDR(dx, dy) - PIXADDR(sx, sy) - es + 1)
+       switch (lcd_dma.rotate) {
+       case 0:
+               if (!lcd_dma.mirror) {
+                       top = PIXADDR(0, 0);
+                       bottom = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
+                       /* 1510 DMA requires the bottom address to be 2 more
+                        * than the actual last memory access location. */
+                       if (omap_dma_in_1510_mode() &&
+                           lcd_dma.data_type == OMAP_DMA_DATA_TYPE_S32)
+                               bottom += 2;
+                       ei = PIXSTEP(0, 0, 1, 0);
+                       fi = PIXSTEP(lcd_dma.xres - 1, 0, 0, 1);
+               } else {
+                       top = PIXADDR(lcd_dma.xres - 1, 0);
+                       bottom = PIXADDR(0, lcd_dma.yres - 1);
+                       ei = PIXSTEP(1, 0, 0, 0);
+                       fi = PIXSTEP(0, 0, lcd_dma.xres - 1, 1);
+               }
+               en = lcd_dma.xres;
+               fn = lcd_dma.yres;
+               break;
+       case 90:
+               if (!lcd_dma.mirror) {
+                       top = PIXADDR(0, lcd_dma.yres - 1);
+                       bottom = PIXADDR(lcd_dma.xres - 1, 0);
+                       ei = PIXSTEP(0, 1, 0, 0);
+                       fi = PIXSTEP(0, 0, 1, lcd_dma.yres - 1);
+               } else {
+                       top = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
+                       bottom = PIXADDR(0, 0);
+                       ei = PIXSTEP(0, 1, 0, 0);
+                       fi = PIXSTEP(1, 0, 0, lcd_dma.yres - 1);
+               }
+               en = lcd_dma.yres;
+               fn = lcd_dma.xres;
+               break;
+       case 180:
+               if (!lcd_dma.mirror) {
+                       top = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
+                       bottom = PIXADDR(0, 0);
+                       ei = PIXSTEP(1, 0, 0, 0);
+                       fi = PIXSTEP(0, 1, lcd_dma.xres - 1, 0);
+               } else {
+                       top = PIXADDR(0, lcd_dma.yres - 1);
+                       bottom = PIXADDR(lcd_dma.xres - 1, 0);
+                       ei = PIXSTEP(0, 0, 1, 0);
+                       fi = PIXSTEP(lcd_dma.xres - 1, 1, 0, 0);
+               }
+               en = lcd_dma.xres;
+               fn = lcd_dma.yres;
+               break;
+       case 270:
+               if (!lcd_dma.mirror) {
+                       top = PIXADDR(lcd_dma.xres - 1, 0);
+                       bottom = PIXADDR(0, lcd_dma.yres - 1);
+                       ei = PIXSTEP(0, 0, 0, 1);
+                       fi = PIXSTEP(1, lcd_dma.yres - 1, 0, 0);
+               } else {
+                       top = PIXADDR(0, 0);
+                       bottom = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
+                       ei = PIXSTEP(0, 0, 0, 1);
+                       fi = PIXSTEP(0, lcd_dma.yres - 1, 1, 0);
+               }
+               en = lcd_dma.yres;
+               fn = lcd_dma.xres;
+               break;
+       default:
+               BUG();
+               return; /* Supress warning about uninitialized vars */
+       }
+
+       if (omap_dma_in_1510_mode()) {
+               omap_writew(top >> 16, OMAP1510_DMA_LCD_TOP_F1_U);
+               omap_writew(top, OMAP1510_DMA_LCD_TOP_F1_L);
+               omap_writew(bottom >> 16, OMAP1510_DMA_LCD_BOT_F1_U);
+               omap_writew(bottom, OMAP1510_DMA_LCD_BOT_F1_L);
+
+               return;
+       }
+
+       /* 1610 regs */
+       omap_writew(top >> 16, OMAP1610_DMA_LCD_TOP_B1_U);
+       omap_writew(top, OMAP1610_DMA_LCD_TOP_B1_L);
+       omap_writew(bottom >> 16, OMAP1610_DMA_LCD_BOT_B1_U);
+       omap_writew(bottom, OMAP1610_DMA_LCD_BOT_B1_L);
+
+       omap_writew(en, OMAP1610_DMA_LCD_SRC_EN_B1);
+       omap_writew(fn, OMAP1610_DMA_LCD_SRC_FN_B1);
+
+       w = omap_readw(OMAP1610_DMA_LCD_CSDP);
+       w &= ~0x03;
+       w |= lcd_dma.data_type;
+       omap_writew(w, OMAP1610_DMA_LCD_CSDP);
+
+       w = omap_readw(OMAP1610_DMA_LCD_CTRL);
+       /* Always set the source port as SDRAM for now*/
+       w &= ~(0x03 << 6);
+       if (lcd_dma.callback != NULL)
+               w |= 1 << 1;            /* Block interrupt enable */
+       else
+               w &= ~(1 << 1);
+       omap_writew(w, OMAP1610_DMA_LCD_CTRL);
+
+       if (!(lcd_dma.rotate || lcd_dma.mirror ||
+             lcd_dma.vxres || lcd_dma.xscale || lcd_dma.yscale))
+               return;
+
+       w = omap_readw(OMAP1610_DMA_LCD_CCR);
+       /* Set the double-indexed addressing mode */
+       w |= (0x03 << 12);
+       omap_writew(w, OMAP1610_DMA_LCD_CCR);
+
+       omap_writew(ei, OMAP1610_DMA_LCD_SRC_EI_B1);
+       omap_writew(fi >> 16, OMAP1610_DMA_LCD_SRC_FI_B1_U);
+       omap_writew(fi, OMAP1610_DMA_LCD_SRC_FI_B1_L);
+}
+
+static irqreturn_t lcd_dma_irq_handler(int irq, void *dev_id,
+                                      struct pt_regs *regs)
+{
+       u16 w;
+
+       w = omap_readw(OMAP1610_DMA_LCD_CTRL);
+       if (unlikely(!(w & (1 << 3)))) {
+               printk(KERN_WARNING "Spurious LCD DMA IRQ\n");
+               return IRQ_NONE;
+       }
+       /* Ack the IRQ */
+       w |= (1 << 3);
+       omap_writew(w, OMAP1610_DMA_LCD_CTRL);
+       lcd_dma.active = 0;
+       if (lcd_dma.callback != NULL)
+               lcd_dma.callback(w, lcd_dma.cb_data);
+
+       return IRQ_HANDLED;
+}
+
+int omap_request_lcd_dma(void (* callback)(u16 status, void *data),
+                        void *data)
+{
+       spin_lock_irq(&lcd_dma.lock);
+       if (lcd_dma.reserved) {
+               spin_unlock_irq(&lcd_dma.lock);
+               printk(KERN_ERR "LCD DMA channel already reserved\n");
+               BUG();
+               return -EBUSY;
+       }
+       lcd_dma.reserved = 1;
+       spin_unlock_irq(&lcd_dma.lock);
+       lcd_dma.callback = callback;
+       lcd_dma.cb_data = data;
+       lcd_dma.active = 0;
+       lcd_dma.single_transfer = 0;
+       lcd_dma.rotate = 0;
+       lcd_dma.vxres = 0;
+       lcd_dma.mirror = 0;
+       lcd_dma.xscale = 0;
+       lcd_dma.yscale = 0;
+       lcd_dma.ext_ctrl = 0;
+       lcd_dma.src_port = 0;
+
+       return 0;
+}
+
+void omap_free_lcd_dma(void)
+{
+       spin_lock(&lcd_dma.lock);
+       if (!lcd_dma.reserved) {
+               spin_unlock(&lcd_dma.lock);
+               printk(KERN_ERR "LCD DMA is not reserved\n");
+               BUG();
+               return;
+       }
+       if (!enable_1510_mode)
+               omap_writew(omap_readw(OMAP1610_DMA_LCD_CCR) & ~1,
+                           OMAP1610_DMA_LCD_CCR);
+       lcd_dma.reserved = 0;
+       spin_unlock(&lcd_dma.lock);
+}
+
+void omap_enable_lcd_dma(void)
+{
+       u16 w;
+
+       /* Set the Enable bit only if an external controller is
+        * connected. Otherwise the OMAP internal controller will
+        * start the transfer when it gets enabled.
+        */
+       if (enable_1510_mode || !lcd_dma.ext_ctrl)
+               return;
+
+       w = omap_readw(OMAP1610_DMA_LCD_CTRL);
+       w |= 1 << 8;
+       omap_writew(w, OMAP1610_DMA_LCD_CTRL);
+
+       lcd_dma.active = 1;
+
+       w = omap_readw(OMAP1610_DMA_LCD_CCR);
+       w |= 1 << 7;
+       omap_writew(w, OMAP1610_DMA_LCD_CCR);
+}
+
+void omap_setup_lcd_dma(void)
+{
+       BUG_ON(lcd_dma.active);
+       if (!enable_1510_mode) {
+               /* Set some reasonable defaults */
+               omap_writew(0x5440, OMAP1610_DMA_LCD_CCR);
+               omap_writew(0x9102, OMAP1610_DMA_LCD_CSDP);
+               omap_writew(0x0004, OMAP1610_DMA_LCD_LCH_CTRL);
+       }
+       set_b1_regs();
+       if (!enable_1510_mode) {
+               u16 w;
+
+               w = omap_readw(OMAP1610_DMA_LCD_CCR);
+               /* If DMA was already active set the end_prog bit to have
+                * the programmed register set loaded into the active
+                * register set.
+                */
+               w |= 1 << 11;           /* End_prog */
+               if (!lcd_dma.single_transfer)
+                       w |= (3 << 8);  /* Auto_init, repeat */
+               omap_writew(w, OMAP1610_DMA_LCD_CCR);
+       }
+}
+
+void omap_stop_lcd_dma(void)
+{
+       u16 w;
+
+       lcd_dma.active = 0;
+       if (enable_1510_mode || !lcd_dma.ext_ctrl)
+               return;
+
+       w = omap_readw(OMAP1610_DMA_LCD_CCR);
+       w &= ~(1 << 7);
+       omap_writew(w, OMAP1610_DMA_LCD_CCR);
+
+       w = omap_readw(OMAP1610_DMA_LCD_CTRL);
+       w &= ~(1 << 8);
+       omap_writew(w, OMAP1610_DMA_LCD_CTRL);
+}
+
+int omap_lcd_dma_ext_running(void)
+{
+       return lcd_dma.ext_ctrl && lcd_dma.active;
+}
+
+/*----------------------------------------------------------------------------*/
+
+static int __init omap_init_dma(void)
+{
+       int ch, r;
+
+       if (cpu_is_omap15xx()) {
+               printk(KERN_INFO "DMA support for OMAP15xx initialized\n");
+               dma_chan_count = 9;
+               enable_1510_mode = 1;
+       } else if (cpu_is_omap16xx() || cpu_is_omap730()) {
+               printk(KERN_INFO "OMAP DMA hardware version %d\n",
+                      omap_readw(OMAP_DMA_HW_ID));
+               printk(KERN_INFO "DMA capabilities: %08x:%08x:%04x:%04x:%04x\n",
+                      (omap_readw(OMAP_DMA_CAPS_0_U) << 16) |
+                      omap_readw(OMAP_DMA_CAPS_0_L),
+                      (omap_readw(OMAP_DMA_CAPS_1_U) << 16) |
+                      omap_readw(OMAP_DMA_CAPS_1_L),
+                      omap_readw(OMAP_DMA_CAPS_2), omap_readw(OMAP_DMA_CAPS_3),
+                      omap_readw(OMAP_DMA_CAPS_4));
+               if (!enable_1510_mode) {
+                       u16 w;
+
+                       /* Disable OMAP 3.0/3.1 compatibility mode. */
+                       w = omap_readw(OMAP_DMA_GSCR);
+                       w |= 1 << 3;
+                       omap_writew(w, OMAP_DMA_GSCR);
+                       dma_chan_count = 16;
+               } else
+                       dma_chan_count = 9;
+       } else if (cpu_is_omap24xx()) {
+               u8 revision = omap_readb(OMAP_DMA4_REVISION);
+               printk(KERN_INFO "OMAP DMA hardware revision %d.%d\n",
+                      revision >> 4, revision & 0xf);
+               dma_chan_count = OMAP_LOGICAL_DMA_CH_COUNT;
+       } else {
+               dma_chan_count = 0;
+               return 0;
+       }
+
+       memset(&lcd_dma, 0, sizeof(lcd_dma));
+       spin_lock_init(&lcd_dma.lock);
+       spin_lock_init(&dma_chan_lock);
+       memset(&dma_chan, 0, sizeof(dma_chan));
+
+       for (ch = 0; ch < dma_chan_count; ch++) {
+               omap_clear_dma(ch);
+               dma_chan[ch].dev_id = -1;
+               dma_chan[ch].next_lch = -1;
+
+               if (ch >= 6 && enable_1510_mode)
+                       continue;
+
+               if (cpu_class_is_omap1()) {
+                       /* request_irq() doesn't like dev_id (ie. ch) being
+                        * zero, so we have to kludge around this. */
+                       r = request_irq(omap1_dma_irq[ch],
+                                       omap1_dma_irq_handler, 0, "DMA",
+                                       (void *) (ch + 1));
+                       if (r != 0) {
+                               int i;
+
+                               printk(KERN_ERR "unable to request IRQ %d "
+                                      "for DMA (error %d)\n",
+                                      omap1_dma_irq[ch], r);
+                               for (i = 0; i < ch; i++)
+                                       free_irq(omap1_dma_irq[i],
+                                                (void *) (i + 1));
+                               return r;
+                       }
+               }
+       }
+
+       if (cpu_is_omap24xx())
+               setup_irq(INT_24XX_SDMA_IRQ0, &omap24xx_dma_irq);
+
+       /* FIXME: Update LCD DMA to work on 24xx */
+       if (cpu_class_is_omap1()) {
+               r = request_irq(INT_DMA_LCD, lcd_dma_irq_handler, 0,
+                               "LCD DMA", NULL);
+               if (r != 0) {
+                       int i;
+
+                       printk(KERN_ERR "unable to request IRQ for LCD DMA "
+                              "(error %d)\n", r);
+                       for (i = 0; i < dma_chan_count; i++)
+                               free_irq(omap1_dma_irq[i], (void *) (i + 1));
+                       return r;
+               }
+       }
+
+       return 0;
+}
+
+arch_initcall(omap_init_dma);
+
+EXPORT_SYMBOL(omap_get_dma_src_pos);
+EXPORT_SYMBOL(omap_get_dma_dst_pos);
+EXPORT_SYMBOL(omap_get_dma_src_addr_counter);
+EXPORT_SYMBOL(omap_clear_dma);
+EXPORT_SYMBOL(omap_set_dma_priority);
+EXPORT_SYMBOL(omap_request_dma);
+EXPORT_SYMBOL(omap_free_dma);
+EXPORT_SYMBOL(omap_start_dma);
+EXPORT_SYMBOL(omap_stop_dma);
+EXPORT_SYMBOL(omap_enable_dma_irq);
+EXPORT_SYMBOL(omap_disable_dma_irq);
+
+EXPORT_SYMBOL(omap_set_dma_transfer_params);
+EXPORT_SYMBOL(omap_set_dma_color_mode);
+
+EXPORT_SYMBOL(omap_set_dma_src_params);
+EXPORT_SYMBOL(omap_set_dma_src_index);
+EXPORT_SYMBOL(omap_set_dma_src_data_pack);
+EXPORT_SYMBOL(omap_set_dma_src_burst_mode);
+
+EXPORT_SYMBOL(omap_set_dma_dest_params);
+EXPORT_SYMBOL(omap_set_dma_dest_index);
+EXPORT_SYMBOL(omap_set_dma_dest_data_pack);
+EXPORT_SYMBOL(omap_set_dma_dest_burst_mode);
+
+EXPORT_SYMBOL(omap_set_dma_params);
+
+EXPORT_SYMBOL(omap_dma_link_lch);
+EXPORT_SYMBOL(omap_dma_unlink_lch);
+
+EXPORT_SYMBOL(omap_request_lcd_dma);
+EXPORT_SYMBOL(omap_free_lcd_dma);
+EXPORT_SYMBOL(omap_enable_lcd_dma);
+EXPORT_SYMBOL(omap_setup_lcd_dma);
+EXPORT_SYMBOL(omap_stop_lcd_dma);
+EXPORT_SYMBOL(omap_lcd_dma_ext_running);
+EXPORT_SYMBOL(omap_set_lcd_dma_b1);
+EXPORT_SYMBOL(omap_set_lcd_dma_single_transfer);
+EXPORT_SYMBOL(omap_set_lcd_dma_ext_controller);
+EXPORT_SYMBOL(omap_set_lcd_dma_b1_rotation);
+EXPORT_SYMBOL(omap_set_lcd_dma_b1_vxres);
+EXPORT_SYMBOL(omap_set_lcd_dma_b1_scale);
+EXPORT_SYMBOL(omap_set_lcd_dma_b1_mirror);
+