--- /dev/null
+/*
+ * User-space DMA and UIO based Redrapids Pocket Change CardBus driver
+ *
+ * Copyright 2008 Vijay Kumar <vijaykumar@bravegnu.org>
+ *
+ * Licensed under GPL version 2 only.
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/uio_driver.h>
+#include <linux/spinlock.h>
+#include <linux/cdev.h>
+#include <linux/delay.h>
+#include <linux/sysfs.h>
+#include <linux/poll.h>
+#include <linux/idr.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/ioctl.h>
+#include <linux/io.h>
+
+#include "poch.h"
+
+#include <asm/cacheflush.h>
+
+#ifndef PCI_VENDOR_ID_RRAPIDS
+#define PCI_VENDOR_ID_RRAPIDS 0x17D2
+#endif
+
+#ifndef PCI_DEVICE_ID_RRAPIDS_POCKET_CHANGE
+#define PCI_DEVICE_ID_RRAPIDS_POCKET_CHANGE 0x0351
+#endif
+
+#define POCH_NCHANNELS 2
+
+#define MAX_POCH_CARDS 8
+#define MAX_POCH_DEVICES (MAX_POCH_CARDS * POCH_NCHANNELS)
+
+#define DRV_NAME "poch"
+#define PFX      DRV_NAME ": "
+
+/*
+ * BAR0 Bridge Register Definitions
+ */
+
+#define BRIDGE_REV_REG                 0x0
+#define BRIDGE_INT_MASK_REG            0x4
+#define BRIDGE_INT_STAT_REG            0x8
+
+#define BRIDGE_INT_ACTIVE              (0x1 << 31)
+#define BRIDGE_INT_FPGA                        (0x1 << 2)
+#define BRIDGE_INT_TEMP_FAIL           (0x1 << 1)
+#define        BRIDGE_INT_TEMP_WARN            (0x1 << 0)
+
+#define BRIDGE_FPGA_RESET_REG          0xC
+
+#define BRIDGE_CARD_POWER_REG          0x10
+#define BRIDGE_CARD_POWER_EN            (0x1 << 0)
+#define BRIDGE_CARD_POWER_PROG_DONE     (0x1 << 31)
+
+#define BRIDGE_JTAG_REG                        0x14
+#define BRIDGE_DMA_GO_REG              0x18
+#define BRIDGE_STAT_0_REG              0x1C
+#define BRIDGE_STAT_1_REG              0x20
+#define BRIDGE_STAT_2_REG              0x24
+#define BRIDGE_STAT_3_REG              0x28
+#define BRIDGE_TEMP_STAT_REG           0x2C
+#define BRIDGE_TEMP_THRESH_REG         0x30
+#define BRIDGE_EEPROM_REVSEL_REG       0x34
+#define BRIDGE_CIS_STRUCT_REG          0x100
+#define BRIDGE_BOARDREV_REG            0x124
+
+/*
+ * BAR1 FPGA Register Definitions
+ */
+
+#define FPGA_IFACE_REV_REG             0x0
+#define FPGA_RX_BLOCK_SIZE_REG         0x8
+#define FPGA_TX_BLOCK_SIZE_REG         0xC
+#define FPGA_RX_BLOCK_COUNT_REG                0x10
+#define FPGA_TX_BLOCK_COUNT_REG                0x14
+#define FPGA_RX_CURR_DMA_BLOCK_REG     0x18
+#define FPGA_TX_CURR_DMA_BLOCK_REG     0x1C
+#define FPGA_RX_GROUP_COUNT_REG                0x20
+#define FPGA_TX_GROUP_COUNT_REG                0x24
+#define FPGA_RX_CURR_GROUP_REG         0x28
+#define FPGA_TX_CURR_GROUP_REG         0x2C
+#define FPGA_RX_CURR_PCI_REG           0x38
+#define FPGA_TX_CURR_PCI_REG           0x3C
+#define FPGA_RX_GROUP0_START_REG       0x40
+#define FPGA_TX_GROUP0_START_REG       0xC0
+#define FPGA_DMA_DESC_1_REG            0x140
+#define FPGA_DMA_DESC_2_REG            0x144
+#define FPGA_DMA_DESC_3_REG            0x148
+#define FPGA_DMA_DESC_4_REG            0x14C
+
+#define FPGA_DMA_INT_STAT_REG          0x150
+#define FPGA_DMA_INT_MASK_REG          0x154
+#define FPGA_DMA_INT_RX                (1 << 0)
+#define FPGA_DMA_INT_TX                (1 << 1)
+
+#define FPGA_RX_GROUPS_PER_INT_REG     0x158
+#define FPGA_TX_GROUPS_PER_INT_REG     0x15C
+#define FPGA_DMA_ADR_PAGE_REG          0x160
+#define FPGA_FPGA_REV_REG              0x200
+
+#define FPGA_ADC_CLOCK_CTL_REG         0x204
+#define FPGA_ADC_CLOCK_CTL_OSC_EN      (0x1 << 3)
+#define FPGA_ADC_CLOCK_LOCAL_CLK       (0x1 | FPGA_ADC_CLOCK_CTL_OSC_EN)
+#define FPGA_ADC_CLOCK_EXT_SAMP_CLK    0X0
+
+#define FPGA_ADC_DAC_EN_REG            0x208
+#define FPGA_ADC_DAC_EN_DAC_OFF         (0x1 << 1)
+#define FPGA_ADC_DAC_EN_ADC_OFF         (0x1 << 0)
+
+#define FPGA_INT_STAT_REG              0x20C
+#define FPGA_INT_MASK_REG              0x210
+#define FPGA_INT_PLL_UNLOCKED          (0x1 << 9)
+#define FPGA_INT_DMA_CORE              (0x1 << 8)
+#define FPGA_INT_TX_FF_EMPTY           (0x1 << 7)
+#define FPGA_INT_RX_FF_EMPTY           (0x1 << 6)
+#define FPGA_INT_TX_FF_OVRFLW          (0x1 << 3)
+#define FPGA_INT_RX_FF_OVRFLW          (0x1 << 2)
+#define FPGA_INT_TX_ACQ_DONE           (0x1 << 1)
+#define FPGA_INT_RX_ACQ_DONE           (0x1)
+
+#define FPGA_RX_ADC_CTL_REG            0x214
+#define FPGA_RX_ADC_CTL_CONT_CAP       (0x0)
+#define FPGA_RX_ADC_CTL_SNAP_CAP       (0x1)
+
+#define FPGA_RX_ARM_REG                        0x21C
+
+#define FPGA_DOM_REG                   0x224
+#define        FPGA_DOM_DCM_RESET              (0x1 << 5)
+#define FPGA_DOM_SOFT_RESET            (0x1 << 4)
+#define FPGA_DOM_DUAL_M_SG_DMA         (0x0)
+#define FPGA_DOM_TARGET_ACCESS         (0x1)
+
+#define FPGA_TX_CTL_REG                        0x228
+#define FPGA_TX_CTL_FIFO_FLUSH          (0x1 << 9)
+#define FPGA_TX_CTL_OUTPUT_ZERO         (0x0 << 2)
+#define FPGA_TX_CTL_OUTPUT_CARDBUS      (0x1 << 2)
+#define FPGA_TX_CTL_OUTPUT_ADC          (0x2 << 2)
+#define FPGA_TX_CTL_OUTPUT_SNAPSHOT     (0x3 << 2)
+#define FPGA_TX_CTL_LOOPBACK            (0x1 << 0)
+
+#define FPGA_ENDIAN_MODE_REG           0x22C
+#define FPGA_RX_FIFO_COUNT_REG         0x28C
+#define FPGA_TX_ENABLE_REG             0x298
+#define FPGA_TX_TRIGGER_REG            0x29C
+#define FPGA_TX_DATAMEM_COUNT_REG      0x2A8
+#define FPGA_CAP_FIFO_REG              0x300
+#define FPGA_TX_SNAPSHOT_REG           0x8000
+
+/*
+ * Channel Index Definitions
+ */
+
+enum {
+       CHNO_RX_CHANNEL,
+       CHNO_TX_CHANNEL,
+};
+
+struct poch_dev;
+
+enum channel_dir {
+       CHANNEL_DIR_RX,
+       CHANNEL_DIR_TX,
+};
+
+struct poch_group_info {
+       struct page *pg;
+       dma_addr_t dma_addr;
+       unsigned long user_offset;
+};
+
+struct channel_info {
+       unsigned int chno;
+
+       atomic_t sys_block_size;
+       atomic_t sys_group_size;
+       atomic_t sys_group_count;
+
+       enum channel_dir dir;
+
+       unsigned long block_size;
+       unsigned long group_size;
+       unsigned long group_count;
+
+       /* Contains the DMA address and VM offset of each group. */
+       struct poch_group_info *groups;
+
+       /* Contains the header and circular buffer exported to userspace. */
+       spinlock_t group_offsets_lock;
+       struct poch_cbuf_header *header;
+       struct page *header_pg;
+       unsigned long header_size;
+
+       /* Last group indicated as 'complete' to user space. */
+       unsigned int transfer;
+
+       wait_queue_head_t wq;
+
+       union {
+               unsigned int data_available;
+               unsigned int space_available;
+       };
+
+       void __iomem *bridge_iomem;
+       void __iomem *fpga_iomem;
+       spinlock_t *iomem_lock;
+
+       atomic_t free;
+       atomic_t inited;
+
+       /* Error counters */
+       struct poch_counters counters;
+       spinlock_t counters_lock;
+
+       struct device *dev;
+};
+
+struct poch_dev {
+       struct uio_info uio;
+       struct pci_dev *pci_dev;
+       unsigned int nchannels;
+       struct channel_info channels[POCH_NCHANNELS];
+       struct cdev cdev;
+
+       /* Counts the no. of channels that have been opened. On first
+        * open, the card is powered on. On last channel close, the
+        * card is powered off.
+        */
+       atomic_t usage;
+
+       void __iomem *bridge_iomem;
+       void __iomem *fpga_iomem;
+       spinlock_t iomem_lock;
+
+       struct device *dev;
+};
+
+static dev_t poch_first_dev;
+static struct class *poch_cls;
+static DEFINE_IDR(poch_ids);
+
+static ssize_t store_block_size(struct device *dev,
+                               struct device_attribute *attr,
+                               const char *buf, size_t count)
+{
+       struct channel_info *channel = dev_get_drvdata(dev);
+       unsigned long block_size;
+
+       sscanf(buf, "%lu", &block_size);
+       atomic_set(&channel->sys_block_size, block_size);
+
+       return count;
+}
+static DEVICE_ATTR(block_size, S_IWUSR|S_IWGRP, NULL, store_block_size);
+
+static ssize_t store_group_size(struct device *dev,
+                               struct device_attribute *attr,
+                               const char *buf, size_t count)
+{
+       struct channel_info *channel = dev_get_drvdata(dev);
+       unsigned long group_size;
+
+       sscanf(buf, "%lu", &group_size);
+       atomic_set(&channel->sys_group_size, group_size);
+
+       return count;
+}
+static DEVICE_ATTR(group_size, S_IWUSR|S_IWGRP, NULL, store_group_size);
+
+static ssize_t store_group_count(struct device *dev,
+                               struct device_attribute *attr,
+                                const char *buf, size_t count)
+{
+       struct channel_info *channel = dev_get_drvdata(dev);
+       unsigned long group_count;
+
+       sscanf(buf, "%lu", &group_count);
+       atomic_set(&channel->sys_group_count, group_count);
+
+       return count;
+}
+static DEVICE_ATTR(group_count, S_IWUSR|S_IWGRP, NULL, store_group_count);
+
+static ssize_t show_direction(struct device *dev,
+                             struct device_attribute *attr, char *buf)
+{
+       struct channel_info *channel = dev_get_drvdata(dev);
+       int len;
+
+       len = sprintf(buf, "%s\n", (channel->dir ? "tx" : "rx"));
+       return len;
+}
+static DEVICE_ATTR(dir, S_IRUSR|S_IRGRP, show_direction, NULL);
+
+static ssize_t show_mmap_size(struct device *dev,
+                             struct device_attribute *attr, char *buf)
+{
+       struct channel_info *channel = dev_get_drvdata(dev);
+       int len;
+       unsigned long mmap_size;
+       unsigned long group_pages;
+       unsigned long header_pages;
+       unsigned long total_group_pages;
+
+       /* FIXME: We do not have to add 1, if group_size a multiple of
+          PAGE_SIZE. */
+       group_pages = (channel->group_size / PAGE_SIZE) + 1;
+       header_pages = (channel->header_size / PAGE_SIZE) + 1;
+       total_group_pages = group_pages * channel->group_count;
+
+       mmap_size = (header_pages + total_group_pages) * PAGE_SIZE;
+       len = sprintf(buf, "%lu\n", mmap_size);
+       return len;
+}
+static DEVICE_ATTR(mmap_size, S_IRUSR|S_IRGRP, show_mmap_size, NULL);
+
+static struct device_attribute *poch_class_attrs[] = {
+       &dev_attr_block_size,
+       &dev_attr_group_size,
+       &dev_attr_group_count,
+       &dev_attr_dir,
+       &dev_attr_mmap_size,
+};
+
+static void poch_channel_free_groups(struct channel_info *channel)
+{
+       unsigned long i;
+
+       for (i = 0; i < channel->group_count; i++) {
+               struct poch_group_info *group;
+               unsigned int order;
+
+               group = &channel->groups[i];
+               order = get_order(channel->group_size);
+               if (group->pg)
+                       __free_pages(group->pg, order);
+       }
+}
+
+static int poch_channel_alloc_groups(struct channel_info *channel)
+{
+       unsigned long i;
+       unsigned long group_pages;
+       unsigned long header_pages;
+
+       group_pages = (channel->group_size / PAGE_SIZE) + 1;
+       header_pages = (channel->header_size / PAGE_SIZE) + 1;
+
+       for (i = 0; i < channel->group_count; i++) {
+               struct poch_group_info *group;
+               unsigned int order;
+               gfp_t gfp_mask;
+
+               group = &channel->groups[i];
+               order = get_order(channel->group_size);
+
+               /*
+                * __GFP_COMP is required here since we are going to
+                * perform non-linear mapping to userspace. For more
+                * information read the vm_insert_page() function
+                * comments.
+                */
+
+               gfp_mask = GFP_KERNEL | GFP_DMA32 | __GFP_ZERO;
+               group->pg = alloc_pages(gfp_mask, order);
+               if (!group->pg) {
+                       poch_channel_free_groups(channel);
+                       return -ENOMEM;
+               }
+
+               /* FIXME: This is the physical address not the bus
+                * address!  This won't work in architectures that
+                * have an IOMMU. Can we use pci_map_single() for
+                * this?
+                */
+               group->dma_addr = page_to_pfn(group->pg) * PAGE_SIZE;
+               group->user_offset =
+                       (header_pages + (i * group_pages)) * PAGE_SIZE;
+
+               printk(KERN_INFO PFX "%ld: user_offset: 0x%lx dma: 0x%x\n", i,
+                      group->user_offset, group->dma_addr);
+       }
+
+       return 0;
+}
+
+static void channel_latch_attr(struct channel_info *channel)
+{
+       channel->group_count = atomic_read(&channel->sys_group_count);
+       channel->group_size = atomic_read(&channel->sys_group_size);
+       channel->block_size = atomic_read(&channel->sys_block_size);
+}
+
+/*
+ * Configure DMA group registers
+ */
+static void channel_dma_init(struct channel_info *channel)
+{
+       void __iomem *fpga = channel->fpga_iomem;
+       u32 group_regs_base;
+       u32 group_reg;
+       unsigned int page;
+       unsigned int group_in_page;
+       unsigned long i;
+       u32 block_size_reg;
+       u32 block_count_reg;
+       u32 group_count_reg;
+       u32 groups_per_int_reg;
+       u32 curr_pci_reg;
+
+       if (channel->chno == CHNO_RX_CHANNEL) {
+               group_regs_base = FPGA_RX_GROUP0_START_REG;
+               block_size_reg = FPGA_RX_BLOCK_SIZE_REG;
+               block_count_reg = FPGA_RX_BLOCK_COUNT_REG;
+               group_count_reg = FPGA_RX_GROUP_COUNT_REG;
+               groups_per_int_reg = FPGA_RX_GROUPS_PER_INT_REG;
+               curr_pci_reg = FPGA_RX_CURR_PCI_REG;
+       } else {
+               group_regs_base = FPGA_TX_GROUP0_START_REG;
+               block_size_reg = FPGA_TX_BLOCK_SIZE_REG;
+               block_count_reg = FPGA_TX_BLOCK_COUNT_REG;
+               group_count_reg = FPGA_TX_GROUP_COUNT_REG;
+               groups_per_int_reg = FPGA_TX_GROUPS_PER_INT_REG;
+               curr_pci_reg = FPGA_TX_CURR_PCI_REG;
+       }
+
+       printk(KERN_WARNING "block_size, group_size, group_count\n");
+       iowrite32(channel->block_size, fpga + block_size_reg);
+       iowrite32(channel->group_size / channel->block_size,
+                 fpga + block_count_reg);
+       iowrite32(channel->group_count, fpga + group_count_reg);
+       /* FIXME: Hardcoded groups per int. Get it from sysfs? */
+       iowrite32(1, fpga + groups_per_int_reg);
+
+       /* Unlock PCI address? Not defined in the data sheet, but used
+        * in the reference code by Redrapids.
+        */
+       iowrite32(0x1, fpga + curr_pci_reg);
+
+       /* The DMA address page register is shared between the RX and
+        * TX channels, so acquire lock.
+        */
+       spin_lock(channel->iomem_lock);
+       for (i = 0; i < channel->group_count; i++) {
+               page = i / 32;
+               group_in_page = i % 32;
+
+               group_reg = group_regs_base + (group_in_page * 4);
+
+               iowrite32(page, fpga + FPGA_DMA_ADR_PAGE_REG);
+               iowrite32(channel->groups[i].dma_addr, fpga + group_reg);
+       }
+       for (i = 0; i < channel->group_count; i++) {
+               page = i / 32;
+               group_in_page = i % 32;
+
+               group_reg = group_regs_base + (group_in_page * 4);
+
+               iowrite32(page, fpga + FPGA_DMA_ADR_PAGE_REG);
+               printk(KERN_INFO PFX "%ld: read dma_addr: 0x%x\n", i,
+                      ioread32(fpga + group_reg));
+       }
+       spin_unlock(channel->iomem_lock);
+
+}
+
+static int poch_channel_alloc_header(struct channel_info *channel)
+{
+       struct poch_cbuf_header *header = channel->header;
+       unsigned long group_offset_size;
+       unsigned long tot_group_offsets_size;
+
+       /* Allocate memory to hold header exported userspace */
+       group_offset_size = sizeof(header->group_offsets[0]);
+       tot_group_offsets_size = group_offset_size * channel->group_count;
+       channel->header_size = sizeof(*header) + tot_group_offsets_size;
+       channel->header_pg = alloc_pages(GFP_KERNEL | __GFP_ZERO,
+                                        get_order(channel->header_size));
+       if (!channel->header_pg)
+               return -ENOMEM;
+
+       channel->header = page_address(channel->header_pg);
+
+       return 0;
+}
+
+static void poch_channel_free_header(struct channel_info *channel)
+{
+       unsigned int order;
+
+       order = get_order(channel->header_size);
+       __free_pages(channel->header_pg, order);
+}
+
+static void poch_channel_init_header(struct channel_info *channel)
+{
+       int i;
+       struct poch_group_info *groups;
+       s32 *group_offsets;
+
+       channel->header->group_size_bytes = channel->group_size;
+       channel->header->group_count = channel->group_count;
+
+       spin_lock_init(&channel->group_offsets_lock);
+
+       group_offsets = channel->header->group_offsets;
+       groups = channel->groups;
+
+       for (i = 0; i < channel->group_count; i++) {
+               if (channel->dir == CHANNEL_DIR_RX)
+                       group_offsets[i] = -1;
+               else
+                       group_offsets[i] = groups[i].user_offset;
+       }
+}
+
+static void __poch_channel_clear_counters(struct channel_info *channel)
+{
+       channel->counters.pll_unlock = 0;
+       channel->counters.fifo_empty = 0;
+       channel->counters.fifo_overflow = 0;
+}
+
+static int poch_channel_init(struct channel_info *channel,
+                            struct poch_dev *poch_dev)
+{
+       struct pci_dev *pdev = poch_dev->pci_dev;
+       struct device *dev = &pdev->dev;
+       unsigned long alloc_size;
+       int ret;
+
+       printk(KERN_WARNING "channel_latch_attr\n");
+
+       channel_latch_attr(channel);
+
+       channel->transfer = 0;
+
+       /* Allocate memory to hold group information. */
+       alloc_size = channel->group_count * sizeof(struct poch_group_info);
+       channel->groups = kzalloc(alloc_size, GFP_KERNEL);
+       if (!channel->groups) {
+               dev_err(dev, "error allocating memory for group info\n");
+               ret = -ENOMEM;
+               goto out;
+       }
+
+       printk(KERN_WARNING "poch_channel_alloc_groups\n");
+
+       ret = poch_channel_alloc_groups(channel);
+       if (ret) {
+               dev_err(dev, "error allocating groups of order %d\n",
+                       get_order(channel->group_size));
+               goto out_free_group_info;
+       }
+
+       ret = poch_channel_alloc_header(channel);
+       if (ret) {
+               dev_err(dev, "error allocating user space header\n");
+               goto out_free_groups;
+       }
+
+       channel->fpga_iomem = poch_dev->fpga_iomem;
+       channel->bridge_iomem = poch_dev->bridge_iomem;
+       channel->iomem_lock = &poch_dev->iomem_lock;
+       spin_lock_init(&channel->counters_lock);
+
+       __poch_channel_clear_counters(channel);
+
+       printk(KERN_WARNING "poch_channel_init_header\n");
+
+       poch_channel_init_header(channel);
+
+       return 0;
+
+ out_free_groups:
+       poch_channel_free_groups(channel);
+ out_free_group_info:
+       kfree(channel->groups);
+ out:
+       return ret;
+}
+
+static int poch_wait_fpga_prog(void __iomem *bridge)
+{
+       unsigned long total_wait;
+       const unsigned long wait_period = 100;
+       /* FIXME: Get the actual timeout */
+       const unsigned long prog_timeo = 10000; /* 10 Seconds */
+       u32 card_power;
+
+       printk(KERN_WARNING "poch_wait_fpg_prog\n");
+
+       printk(KERN_INFO PFX "programming fpga ...\n");
+       total_wait = 0;
+       while (1) {
+               msleep(wait_period);
+               total_wait += wait_period;
+
+               card_power = ioread32(bridge + BRIDGE_CARD_POWER_REG);
+               if (card_power & BRIDGE_CARD_POWER_PROG_DONE) {
+                       printk(KERN_INFO PFX "programming done\n");
+                       return 0;
+               }
+               if (total_wait > prog_timeo) {
+                       printk(KERN_ERR PFX
+                              "timed out while programming FPGA\n");
+                       return -EIO;
+               }
+       }
+}
+
+static void poch_card_power_off(struct poch_dev *poch_dev)
+{
+       void __iomem *bridge = poch_dev->bridge_iomem;
+       u32 card_power;
+
+       iowrite32(0, bridge + BRIDGE_INT_MASK_REG);
+       iowrite32(0, bridge + BRIDGE_DMA_GO_REG);
+
+       card_power = ioread32(bridge + BRIDGE_CARD_POWER_REG);
+       iowrite32(card_power & ~BRIDGE_CARD_POWER_EN,
+                 bridge + BRIDGE_CARD_POWER_REG);
+}
+
+enum clk_src {
+       CLK_SRC_ON_BOARD,
+       CLK_SRC_EXTERNAL
+};
+
+static void poch_card_clock_on(void __iomem *fpga)
+{
+       /* FIXME: Get this data through sysfs? */
+       enum clk_src clk_src = CLK_SRC_ON_BOARD;
+
+       if (clk_src == CLK_SRC_ON_BOARD) {
+               iowrite32(FPGA_ADC_CLOCK_LOCAL_CLK | FPGA_ADC_CLOCK_CTL_OSC_EN,
+                         fpga + FPGA_ADC_CLOCK_CTL_REG);
+       } else if (clk_src == CLK_SRC_EXTERNAL) {
+               iowrite32(FPGA_ADC_CLOCK_EXT_SAMP_CLK,
+                         fpga + FPGA_ADC_CLOCK_CTL_REG);
+       }
+}
+
+static int poch_card_power_on(struct poch_dev *poch_dev)
+{
+       void __iomem *bridge = poch_dev->bridge_iomem;
+       void __iomem *fpga = poch_dev->fpga_iomem;
+
+       iowrite32(BRIDGE_CARD_POWER_EN, bridge + BRIDGE_CARD_POWER_REG);
+
+       if (poch_wait_fpga_prog(bridge) != 0) {
+               poch_card_power_off(poch_dev);
+               return -EIO;
+       }
+
+       poch_card_clock_on(fpga);
+
+       /* Sync to new clock, reset state machines, set DMA mode. */
+       iowrite32(FPGA_DOM_DCM_RESET | FPGA_DOM_SOFT_RESET
+                 | FPGA_DOM_DUAL_M_SG_DMA, fpga + FPGA_DOM_REG);
+
+       /* FIXME: The time required for sync. needs to be tuned. */
+       msleep(1000);
+
+       return 0;
+}
+
+static void poch_channel_analog_on(struct channel_info *channel)
+{
+       void __iomem *fpga = channel->fpga_iomem;
+       u32 adc_dac_en;
+
+       spin_lock(channel->iomem_lock);
+       adc_dac_en = ioread32(fpga + FPGA_ADC_DAC_EN_REG);
+       switch (channel->chno) {
+       case CHNO_RX_CHANNEL:
+               iowrite32(adc_dac_en & ~FPGA_ADC_DAC_EN_ADC_OFF,
+                         fpga + FPGA_ADC_DAC_EN_REG);
+               break;
+       case CHNO_TX_CHANNEL:
+               iowrite32(adc_dac_en & ~FPGA_ADC_DAC_EN_DAC_OFF,
+                         fpga + FPGA_ADC_DAC_EN_REG);
+               break;
+       }
+       spin_unlock(channel->iomem_lock);
+}
+
+static int poch_open(struct inode *inode, struct file *filp)
+{
+       struct poch_dev *poch_dev;
+       struct channel_info *channel;
+       void __iomem *bridge;
+       void __iomem *fpga;
+       int chno;
+       int usage;
+       int ret;
+
+       poch_dev = container_of(inode->i_cdev, struct poch_dev, cdev);
+       bridge = poch_dev->bridge_iomem;
+       fpga = poch_dev->fpga_iomem;
+
+       chno = iminor(inode) % poch_dev->nchannels;
+       channel = &poch_dev->channels[chno];
+
+       if (!atomic_dec_and_test(&channel->free)) {
+               atomic_inc(&channel->free);
+               ret = -EBUSY;
+               goto out;
+       }
+
+       usage = atomic_inc_return(&poch_dev->usage);
+
+       printk(KERN_WARNING "poch_card_power_on\n");
+
+       if (usage == 1) {
+               ret = poch_card_power_on(poch_dev);
+               if (ret)
+                       goto out_dec_usage;
+       }
+
+       printk(KERN_INFO "CardBus Bridge Revision: %x\n",
+              ioread32(bridge + BRIDGE_REV_REG));
+       printk(KERN_INFO "CardBus Interface Revision: %x\n",
+              ioread32(fpga + FPGA_IFACE_REV_REG));
+
+       channel->chno = chno;
+       filp->private_data = channel;
+
+       printk(KERN_WARNING "poch_channel_init\n");
+
+       ret = poch_channel_init(channel, poch_dev);
+       if (ret)
+               goto out_power_off;
+
+       poch_channel_analog_on(channel);
+
+       printk(KERN_WARNING "channel_dma_init\n");
+
+       channel_dma_init(channel);
+
+       printk(KERN_WARNING "poch_channel_analog_on\n");
+
+       if (usage == 1) {
+               printk(KERN_WARNING "setting up DMA\n");
+
+               /* Initialize DMA Controller. */
+               iowrite32(FPGA_CAP_FIFO_REG, bridge + BRIDGE_STAT_2_REG);
+               iowrite32(FPGA_DMA_DESC_1_REG, bridge + BRIDGE_STAT_3_REG);
+
+               ioread32(fpga + FPGA_DMA_INT_STAT_REG);
+               ioread32(fpga + FPGA_INT_STAT_REG);
+               ioread32(bridge + BRIDGE_INT_STAT_REG);
+
+               /* Initialize Interrupts. FIXME: Enable temperature
+                * handling We are enabling both Tx and Rx channel
+                * interrupts here. Do we need to enable interrupts
+                * only for the current channel? Anyways we won't get
+                * the interrupt unless the DMA is activated.
+                */
+               iowrite32(BRIDGE_INT_FPGA, bridge + BRIDGE_INT_MASK_REG);
+               iowrite32(FPGA_INT_DMA_CORE
+                         | FPGA_INT_PLL_UNLOCKED
+                         | FPGA_INT_TX_FF_EMPTY
+                         | FPGA_INT_RX_FF_EMPTY
+                         | FPGA_INT_TX_FF_OVRFLW
+                         | FPGA_INT_RX_FF_OVRFLW,
+                         fpga + FPGA_INT_MASK_REG);
+               iowrite32(FPGA_DMA_INT_RX | FPGA_DMA_INT_TX,
+                         fpga + FPGA_DMA_INT_MASK_REG);
+       }
+
+       if (channel->dir == CHANNEL_DIR_TX) {
+               /* Flush TX FIFO and output data from cardbus. */
+               iowrite32(FPGA_TX_CTL_FIFO_FLUSH
+                         | FPGA_TX_CTL_OUTPUT_CARDBUS,
+                         fpga + FPGA_TX_CTL_REG);
+       }
+
+       atomic_inc(&channel->inited);
+
+       return 0;
+
+ out_power_off:
+       if (usage == 1)
+               poch_card_power_off(poch_dev);
+ out_dec_usage:
+       atomic_dec(&poch_dev->usage);
+       atomic_inc(&channel->free);
+ out:
+       return ret;
+}
+
+static int poch_release(struct inode *inode, struct file *filp)
+{
+       struct channel_info *channel = filp->private_data;
+       struct poch_dev *poch_dev;
+       int usage;
+
+       poch_dev = container_of(inode->i_cdev, struct poch_dev, cdev);
+
+       usage = atomic_dec_return(&poch_dev->usage);
+       if (usage == 0) {
+               printk(KERN_WARNING "poch_card_power_off\n");
+               poch_card_power_off(poch_dev);
+       }
+
+       atomic_dec(&channel->inited);
+       poch_channel_free_header(channel);
+       poch_channel_free_groups(channel);
+       kfree(channel->groups);
+       atomic_inc(&channel->free);
+
+       return 0;
+}
+
+/*
+ * Map the header and the group buffers, to user space.
+ */
+static int poch_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+       struct channel_info *channel = filp->private_data;
+
+       unsigned long start;
+       unsigned long size;
+
+       unsigned long group_pages;
+       unsigned long header_pages;
+       unsigned long total_group_pages;
+
+       int pg_num;
+       struct page *pg;
+
+       int i;
+       int ret;
+
+       printk(KERN_WARNING "poch_mmap\n");
+
+       if (vma->vm_pgoff) {
+               printk(KERN_WARNING PFX "page offset: %lu\n", vma->vm_pgoff);
+               return -EINVAL;
+       }
+
+       group_pages = (channel->group_size / PAGE_SIZE) + 1;
+       header_pages = (channel->header_size / PAGE_SIZE) + 1;
+       total_group_pages = group_pages * channel->group_count;
+
+       size = vma->vm_end - vma->vm_start;
+       if (size != (header_pages + total_group_pages) * PAGE_SIZE) {
+               printk(KERN_WARNING PFX "required %lu bytes\n", size);
+               return -EINVAL;
+       }
+
+       start = vma->vm_start;
+
+       /* FIXME: Cleanup required on failure? */
+       pg = channel->header_pg;
+       for (pg_num = 0; pg_num < header_pages; pg_num++, pg++) {
+               printk(KERN_DEBUG PFX "page_count: %d\n", page_count(pg));
+               printk(KERN_DEBUG PFX "%d: header: 0x%lx\n", pg_num, start);
+               ret = vm_insert_page(vma, start, pg);
+               if (ret) {
+                       printk(KERN_DEBUG "vm_insert 1 failed at %lx\n", start);
+                       return ret;
+               }
+               start += PAGE_SIZE;
+       }
+
+       for (i = 0; i < channel->group_count; i++) {
+               pg = channel->groups[i].pg;
+               for (pg_num = 0; pg_num < group_pages; pg_num++, pg++) {
+                       printk(KERN_DEBUG PFX "%d: group %d: 0x%lx\n",
+                              pg_num, i, start);
+                       ret = vm_insert_page(vma, start, pg);
+                       if (ret) {
+                               printk(KERN_DEBUG PFX
+                                      "vm_insert 2 failed at %d\n", pg_num);
+                               return ret;
+                       }
+                       start += PAGE_SIZE;
+               }
+       }
+
+       return 0;
+}
+
+/*
+ * Check whether there is some group that the user space has not
+ * consumed yet. When the user space consumes a group, it sets it to
+ * -1. Cosuming could be reading data in case of RX and filling a
+ * buffer in case of TX.
+ */
+static int poch_channel_available(struct channel_info *channel)
+{
+       int i;
+
+       spin_lock_irq(&channel->group_offsets_lock);
+
+       for (i = 0; i < channel->group_count; i++) {
+               if (channel->dir == CHANNEL_DIR_RX
+                   && channel->header->group_offsets[i] == -1) {
+                       spin_unlock_irq(&channel->group_offsets_lock);
+                       return 1;
+               }
+
+               if (channel->dir == CHANNEL_DIR_TX
+                   && channel->header->group_offsets[i] != -1) {
+                       spin_unlock_irq(&channel->group_offsets_lock);
+                       return 1;
+               }
+       }
+
+       spin_unlock_irq(&channel->group_offsets_lock);
+
+       return 0;
+}
+
+static unsigned int poch_poll(struct file *filp, poll_table *pt)
+{
+       struct channel_info *channel = filp->private_data;
+       unsigned int ret = 0;
+
+       poll_wait(filp, &channel->wq, pt);
+
+       if (poch_channel_available(channel)) {
+               if (channel->dir == CHANNEL_DIR_RX)
+                       ret = POLLIN | POLLRDNORM;
+               else
+                       ret = POLLOUT | POLLWRNORM;
+       }
+
+       return ret;
+}
+
+static int poch_ioctl(struct inode *inode, struct file *filp,
+                     unsigned int cmd, unsigned long arg)
+{
+       struct channel_info *channel = filp->private_data;
+       void __iomem *fpga = channel->fpga_iomem;
+       void __iomem *bridge = channel->bridge_iomem;
+       void __user *argp = (void __user *)arg;
+       struct vm_area_struct *vms;
+       struct poch_counters counters;
+       int ret;
+
+       switch (cmd) {
+       case POCH_IOC_TRANSFER_START:
+               switch (channel->chno) {
+               case CHNO_TX_CHANNEL:
+                       printk(KERN_INFO PFX "ioctl: Tx start\n");
+                       iowrite32(0x1, fpga + FPGA_TX_TRIGGER_REG);
+                       iowrite32(0x1, fpga + FPGA_TX_ENABLE_REG);
+
+                       /* FIXME: Does it make sense to do a DMA GO
+                        * twice, once in Tx and once in Rx.
+                        */
+                       iowrite32(0x1, bridge + BRIDGE_DMA_GO_REG);
+                       break;
+               case CHNO_RX_CHANNEL:
+                       printk(KERN_INFO PFX "ioctl: Rx start\n");
+                       iowrite32(0x1, fpga + FPGA_RX_ARM_REG);
+                       iowrite32(0x1, bridge + BRIDGE_DMA_GO_REG);
+                       break;
+               }
+               break;
+       case POCH_IOC_TRANSFER_STOP:
+               switch (channel->chno) {
+               case CHNO_TX_CHANNEL:
+                       printk(KERN_INFO PFX "ioctl: Tx stop\n");
+                       iowrite32(0x0, fpga + FPGA_TX_ENABLE_REG);
+                       iowrite32(0x0, fpga + FPGA_TX_TRIGGER_REG);
+                       iowrite32(0x0, bridge + BRIDGE_DMA_GO_REG);
+                       break;
+               case CHNO_RX_CHANNEL:
+                       printk(KERN_INFO PFX "ioctl: Rx stop\n");
+                       iowrite32(0x0, fpga + FPGA_RX_ARM_REG);
+                       iowrite32(0x0, bridge + BRIDGE_DMA_GO_REG);
+                       break;
+               }
+               break;
+       case POCH_IOC_GET_COUNTERS:
+               if (access_ok(VERIFY_WRITE, argp, sizeof(struct poch_counters)))
+                       return -EFAULT;
+
+               spin_lock_irq(&channel->counters_lock);
+               counters = channel->counters;
+               __poch_channel_clear_counters(channel);
+               spin_unlock_irq(&channel->counters_lock);
+
+               ret = copy_to_user(argp, &counters,
+                                  sizeof(struct poch_counters));
+               if (ret)
+                       return ret;
+
+               break;
+       case POCH_IOC_SYNC_GROUP_FOR_USER:
+       case POCH_IOC_SYNC_GROUP_FOR_DEVICE:
+               vms = find_vma(current->mm, arg);
+               if (!vms)
+                       /* Address not mapped. */
+                       return -EINVAL;
+               if (vms->vm_file != filp)
+                       /* Address mapped from different device/file. */
+                       return -EINVAL;
+
+               flush_cache_range(vms, arg, arg + channel->group_size);
+               break;
+       }
+       return 0;
+}
+
+static struct file_operations poch_fops = {
+       .owner = THIS_MODULE,
+       .open = poch_open,
+       .release = poch_release,
+       .ioctl = poch_ioctl,
+       .poll = poch_poll,
+       .mmap = poch_mmap
+};
+
+static void poch_irq_dma(struct channel_info *channel)
+{
+       u32 prev_transfer;
+       u32 curr_transfer;
+       long groups_done;
+       unsigned long i, j;
+       struct poch_group_info *groups;
+       s32 *group_offsets;
+       u32 curr_group_reg;
+
+       if (!atomic_read(&channel->inited))
+               return;
+
+       prev_transfer = channel->transfer;
+
+       if (channel->chno == CHNO_RX_CHANNEL)
+               curr_group_reg = FPGA_RX_CURR_GROUP_REG;
+       else
+               curr_group_reg = FPGA_TX_CURR_GROUP_REG;
+
+       curr_transfer = ioread32(channel->fpga_iomem + curr_group_reg);
+
+       groups_done = curr_transfer - prev_transfer;
+       /* Check wrap over, and handle it. */
+       if (groups_done <= 0)
+               groups_done += channel->group_count;
+
+       group_offsets = channel->header->group_offsets;
+       groups = channel->groups;
+
+       spin_lock(&channel->group_offsets_lock);
+
+       for (i = 0; i < groups_done; i++) {
+               j = (prev_transfer + i) % channel->group_count;
+               if (channel->dir == CHANNEL_DIR_RX)
+                       group_offsets[j] = -1;
+               else
+                       group_offsets[j] = groups[j].user_offset;
+       }
+
+       spin_unlock(&channel->group_offsets_lock);
+
+       channel->transfer = curr_transfer;
+
+       wake_up_interruptible(&channel->wq);
+}
+
+static irqreturn_t poch_irq_handler(int irq, void *p)
+{
+       struct poch_dev *poch_dev = p;
+       void __iomem *bridge = poch_dev->bridge_iomem;
+       void __iomem *fpga = poch_dev->fpga_iomem;
+       struct channel_info *channel_rx = &poch_dev->channels[CHNO_RX_CHANNEL];
+       struct channel_info *channel_tx = &poch_dev->channels[CHNO_TX_CHANNEL];
+       u32 bridge_stat;
+       u32 fpga_stat;
+       u32 dma_stat;
+
+       bridge_stat = ioread32(bridge + BRIDGE_INT_STAT_REG);
+       fpga_stat = ioread32(fpga + FPGA_INT_STAT_REG);
+       dma_stat = ioread32(fpga + FPGA_DMA_INT_STAT_REG);
+
+       ioread32(fpga + FPGA_DMA_INT_STAT_REG);
+       ioread32(fpga + FPGA_INT_STAT_REG);
+       ioread32(bridge + BRIDGE_INT_STAT_REG);
+
+       if (bridge_stat & BRIDGE_INT_FPGA) {
+               if (fpga_stat & FPGA_INT_DMA_CORE) {
+                       if (dma_stat & FPGA_DMA_INT_RX)
+                               poch_irq_dma(channel_rx);
+                       if (dma_stat & FPGA_DMA_INT_TX)
+                               poch_irq_dma(channel_tx);
+               }
+               if (fpga_stat & FPGA_INT_PLL_UNLOCKED) {
+                       channel_tx->counters.pll_unlock++;
+                       channel_rx->counters.pll_unlock++;
+                       if (printk_ratelimit())
+                               printk(KERN_WARNING PFX "PLL unlocked\n");
+               }
+               if (fpga_stat & FPGA_INT_TX_FF_EMPTY)
+                       channel_tx->counters.fifo_empty++;
+               if (fpga_stat & FPGA_INT_TX_FF_OVRFLW)
+                       channel_tx->counters.fifo_overflow++;
+               if (fpga_stat & FPGA_INT_RX_FF_EMPTY)
+                       channel_rx->counters.fifo_empty++;
+               if (fpga_stat & FPGA_INT_RX_FF_OVRFLW)
+                       channel_rx->counters.fifo_overflow++;
+
+               /*
+                * FIXME: These errors should be notified through the
+                * poll interface as POLLERR.
+                */
+
+               /* Re-enable interrupts. */
+               iowrite32(BRIDGE_INT_FPGA, bridge + BRIDGE_INT_MASK_REG);
+
+               return IRQ_HANDLED;
+       }
+
+       return IRQ_NONE;
+}
+
+static void poch_class_dev_unregister(struct poch_dev *poch_dev, int id)
+{
+       int i, j;
+       int nattrs;
+       struct channel_info *channel;
+       dev_t devno;
+
+       if (poch_dev->dev == NULL)
+               return;
+
+       for (i = 0; i < poch_dev->nchannels; i++) {
+               channel = &poch_dev->channels[i];
+               devno = poch_first_dev + (id * poch_dev->nchannels) + i;
+
+               if (!channel->dev)
+                       continue;
+
+               nattrs = sizeof(poch_class_attrs)/sizeof(poch_class_attrs[0]);
+               for (j = 0; j < nattrs; j++)
+                       device_remove_file(channel->dev, poch_class_attrs[j]);
+
+               device_unregister(channel->dev);
+       }
+
+       device_unregister(poch_dev->dev);
+}
+
+static int __devinit poch_class_dev_register(struct poch_dev *poch_dev,
+                                            int id)
+{
+       struct device *dev = &poch_dev->pci_dev->dev;
+       int i, j;
+       int nattrs;
+       int ret;
+       struct channel_info *channel;
+       dev_t devno;
+
+       poch_dev->dev = device_create(poch_cls, &poch_dev->pci_dev->dev,
+                                     MKDEV(0, 0), NULL, "poch%d", id);
+       if (IS_ERR(poch_dev->dev)) {
+               dev_err(dev, "error creating parent class device");
+               ret = PTR_ERR(poch_dev->dev);
+               poch_dev->dev = NULL;
+               return ret;
+       }
+
+       for (i = 0; i < poch_dev->nchannels; i++) {
+               channel = &poch_dev->channels[i];
+
+               devno = poch_first_dev + (id * poch_dev->nchannels) + i;
+               channel->dev = device_create(poch_cls, poch_dev->dev, devno,
+                                            NULL, "ch%d", i);
+               if (IS_ERR(channel->dev)) {
+                       dev_err(dev, "error creating channel class device");
+                       ret = PTR_ERR(channel->dev);
+                       channel->dev = NULL;
+                       poch_class_dev_unregister(poch_dev, id);
+                       return ret;
+               }
+
+               dev_set_drvdata(channel->dev, channel);
+               nattrs = sizeof(poch_class_attrs)/sizeof(poch_class_attrs[0]);
+               for (j = 0; j < nattrs; j++) {
+                       ret = device_create_file(channel->dev,
+                                                poch_class_attrs[j]);
+                       if (ret) {
+                               dev_err(dev, "error creating attribute file");
+                               poch_class_dev_unregister(poch_dev, id);
+                               return ret;
+                       }
+               }
+       }
+
+       return 0;
+}
+
+static int __devinit poch_pci_probe(struct pci_dev *pdev,
+                                   const struct pci_device_id *pci_id)
+{
+       struct device *dev = &pdev->dev;
+       struct poch_dev *poch_dev;
+       struct uio_info *uio;
+       int ret;
+       int id;
+       int i;
+
+       poch_dev = kzalloc(sizeof(struct poch_dev), GFP_KERNEL);
+       if (!poch_dev) {
+               dev_err(dev, "error allocating priv. data memory\n");
+               return -ENOMEM;
+       }
+
+       poch_dev->pci_dev = pdev;
+       uio = &poch_dev->uio;
+
+       pci_set_drvdata(pdev, poch_dev);
+
+       spin_lock_init(&poch_dev->iomem_lock);
+
+       poch_dev->nchannels = POCH_NCHANNELS;
+       poch_dev->channels[CHNO_RX_CHANNEL].dir = CHANNEL_DIR_RX;
+       poch_dev->channels[CHNO_TX_CHANNEL].dir = CHANNEL_DIR_TX;
+
+       for (i = 0; i < poch_dev->nchannels; i++) {
+               init_waitqueue_head(&poch_dev->channels[i].wq);
+               atomic_set(&poch_dev->channels[i].free, 1);
+               atomic_set(&poch_dev->channels[i].inited, 0);
+       }
+
+       ret = pci_enable_device(pdev);
+       if (ret) {
+               dev_err(dev, "error enabling device\n");
+               goto out_free;
+       }
+
+       ret = pci_request_regions(pdev, "poch");
+       if (ret) {
+               dev_err(dev, "error requesting resources\n");
+               goto out_disable;
+       }
+
+       uio->mem[0].addr = pci_resource_start(pdev, 1);
+       if (!uio->mem[0].addr) {
+               dev_err(dev, "invalid BAR1\n");
+               ret = -ENODEV;
+               goto out_release;
+       }
+
+       uio->mem[0].size = pci_resource_len(pdev, 1);
+       uio->mem[0].memtype = UIO_MEM_PHYS;
+
+       uio->name = "poch";
+       uio->version = "0.0.1";
+       uio->irq = -1;
+       ret = uio_register_device(dev, uio);
+       if (ret) {
+               dev_err(dev, "error register UIO device: %d\n", ret);
+               goto out_release;
+       }
+
+       poch_dev->bridge_iomem = ioremap(pci_resource_start(pdev, 0),
+                                        pci_resource_len(pdev, 0));
+       if (poch_dev->bridge_iomem == NULL) {
+               dev_err(dev, "error mapping bridge (bar0) registers\n");
+               ret = -ENOMEM;
+               goto out_uio_unreg;
+       }
+
+       poch_dev->fpga_iomem = ioremap(pci_resource_start(pdev, 1),
+                                      pci_resource_len(pdev, 1));
+       if (poch_dev->fpga_iomem == NULL) {
+               dev_err(dev, "error mapping fpga (bar1) registers\n");
+               ret = -ENOMEM;
+               goto out_bar0_unmap;
+       }
+
+       ret = request_irq(pdev->irq, poch_irq_handler, IRQF_SHARED,
+                         dev->bus_id, poch_dev);
+       if (ret) {
+               dev_err(dev, "error requesting IRQ %u\n", pdev->irq);
+               ret = -ENOMEM;
+               goto out_bar1_unmap;
+       }
+
+       if (!idr_pre_get(&poch_ids, GFP_KERNEL)) {
+               dev_err(dev, "error allocating memory ids\n");
+               ret = -ENOMEM;
+               goto out_free_irq;
+       }
+
+       idr_get_new(&poch_ids, poch_dev, &id);
+       if (id >= MAX_POCH_CARDS) {
+               dev_err(dev, "minors exhausted\n");
+               ret = -EBUSY;
+               goto out_free_irq;
+       }
+
+       cdev_init(&poch_dev->cdev, &poch_fops);
+       poch_dev->cdev.owner = THIS_MODULE;
+       ret = cdev_add(&poch_dev->cdev,
+                      poch_first_dev + (id * poch_dev->nchannels),
+                      poch_dev->nchannels);
+       if (ret) {
+               dev_err(dev, "error register character device\n");
+               goto out_idr_remove;
+       }
+
+       ret = poch_class_dev_register(poch_dev, id);
+       if (ret)
+               goto out_cdev_del;
+
+       return 0;
+
+ out_cdev_del:
+       cdev_del(&poch_dev->cdev);
+ out_idr_remove:
+       idr_remove(&poch_ids, id);
+ out_free_irq:
+       free_irq(pdev->irq, poch_dev);
+ out_bar1_unmap:
+       iounmap(poch_dev->fpga_iomem);
+ out_bar0_unmap:
+       iounmap(poch_dev->bridge_iomem);
+ out_uio_unreg:
+       uio_unregister_device(uio);
+ out_release:
+       pci_release_regions(pdev);
+ out_disable:
+       pci_disable_device(pdev);
+ out_free:
+       kfree(poch_dev);
+       return ret;
+}
+
+/*
+ * FIXME: We are yet to handle the hot unplug case.
+ */
+static void poch_pci_remove(struct pci_dev *pdev)
+{
+       struct poch_dev *poch_dev = pci_get_drvdata(pdev);
+       struct uio_info *uio = &poch_dev->uio;
+       unsigned int minor = MINOR(poch_dev->cdev.dev);
+       unsigned int id = minor / poch_dev->nchannels;
+
+       /* FIXME: unmap fpga_iomem and bridge_iomem */
+
+       poch_class_dev_unregister(poch_dev, id);
+       cdev_del(&poch_dev->cdev);
+       idr_remove(&poch_ids, id);
+       free_irq(pdev->irq, poch_dev);
+       uio_unregister_device(uio);
+       pci_release_regions(pdev);
+       pci_disable_device(pdev);
+       pci_set_drvdata(pdev, NULL);
+       iounmap(uio->mem[0].internal_addr);
+
+       kfree(poch_dev);
+}
+
+static const struct pci_device_id poch_pci_ids[] /* __devinitconst */ = {
+       { PCI_DEVICE(PCI_VENDOR_ID_RRAPIDS,
+                    PCI_DEVICE_ID_RRAPIDS_POCKET_CHANGE) },
+       { 0, }
+};
+
+static struct pci_driver poch_pci_driver = {
+       .name = DRV_NAME,
+       .id_table = poch_pci_ids,
+       .probe = poch_pci_probe,
+       .remove = poch_pci_remove,
+};
+
+static int __init poch_init_module(void)
+{
+       int ret = 0;
+
+       ret = alloc_chrdev_region(&poch_first_dev, 0,
+                                 MAX_POCH_DEVICES, DRV_NAME);
+       if (ret) {
+               printk(KERN_ERR PFX "error allocating device no.");
+               return ret;
+       }
+
+       poch_cls = class_create(THIS_MODULE, "pocketchange");
+       if (IS_ERR(poch_cls)) {
+               ret = PTR_ERR(poch_cls);
+               goto out_unreg_chrdev;
+       }
+
+       ret = pci_register_driver(&poch_pci_driver);
+       if (ret) {
+               printk(KERN_ERR PFX "error register PCI device");
+               goto out_class_destroy;
+       }
+
+       return 0;
+
+ out_class_destroy:
+       class_destroy(poch_cls);
+
+ out_unreg_chrdev:
+       unregister_chrdev_region(poch_first_dev, MAX_POCH_DEVICES);
+
+       return ret;
+}
+
+static void __exit poch_exit_module(void)
+{
+       pci_unregister_driver(&poch_pci_driver);
+       class_destroy(poch_cls);
+       unregister_chrdev_region(poch_first_dev, MAX_POCH_DEVICES);
+}
+
+module_init(poch_init_module);
+module_exit(poch_exit_module);
+
+MODULE_LICENSE("GPL v2");