blob: 94c5d27d24d7a58b7ea4de184234c47e7e1970dc [file] [log] [blame]
/*
* Brontes PCI frame grabber driver
*
* Copyright (C) 2008 3M Company
* Contact: Justin Bronder <jsbronder@brontes3d.com>
* Original Authors: Daniel Drake <ddrake@brontes3d.com>
* Duane Griffin <duaneg@dghda.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/ioctl.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/types.h>
#include <linux/cdev.h>
#include <linux/list.h>
#include <linux/poll.h>
#include <linux/wait.h>
#include <linux/mm.h>
#include <linux/uaccess.h>
static unsigned int b3dfg_nbuf = 2;
module_param_named(buffer_count, b3dfg_nbuf, uint, 0444);
MODULE_PARM_DESC(buffer_count, "Number of buffers (min 2, default 2)");
MODULE_AUTHOR("Daniel Drake <ddrake@brontes3d.com>");
MODULE_DESCRIPTION("Brontes frame grabber driver");
MODULE_LICENSE("GPL");
#define DRIVER_NAME "b3dfg"
#define B3DFG_MAX_DEVS 4
#define B3DFG_FRAMES_PER_BUFFER 3
#define B3DFG_BAR_REGS 0
#define B3DFG_REGS_LENGTH 0x10000
#define B3DFG_IOC_MAGIC 0xb3 /* dfg :-) */
#define B3DFG_IOCGFRMSZ _IOR(B3DFG_IOC_MAGIC, 1, int)
#define B3DFG_IOCTNUMBUFS _IO(B3DFG_IOC_MAGIC, 2)
#define B3DFG_IOCTTRANS _IO(B3DFG_IOC_MAGIC, 3)
#define B3DFG_IOCTQUEUEBUF _IO(B3DFG_IOC_MAGIC, 4)
#define B3DFG_IOCTPOLLBUF _IOWR(B3DFG_IOC_MAGIC, 5, struct b3dfg_poll)
#define B3DFG_IOCTWAITBUF _IOWR(B3DFG_IOC_MAGIC, 6, struct b3dfg_wait)
#define B3DFG_IOCGWANDSTAT _IOR(B3DFG_IOC_MAGIC, 7, int)
enum {
/* number of 4kb pages per frame */
B3D_REG_FRM_SIZE = 0x0,
/* bit 0: set to enable interrupts
* bit 1: set to enable cable status change interrupts */
B3D_REG_HW_CTRL = 0x4,
/* bit 0-1 - 1-based ID of next pending frame transfer (0 = none)
* bit 2 indicates the previous DMA transfer has completed
* bit 3 indicates wand cable status change
* bit 8:15 - counter of number of discarded triplets */
B3D_REG_DMA_STS = 0x8,
/* bit 0: wand status (1 = present, 0 = disconnected) */
B3D_REG_WAND_STS = 0xc,
/* bus address for DMA transfers. lower 2 bits must be zero because DMA
* works with 32 bit word size. */
B3D_REG_EC220_DMA_ADDR = 0x8000,
/* bit 20:0 - number of 32 bit words to be transferred
* bit 21:31 - reserved */
B3D_REG_EC220_TRF_SIZE = 0x8004,
/* bit 0 - error bit
* bit 1 - interrupt bit (set to generate interrupt at end of transfer)
* bit 2 - start bit (set to start transfer)
* bit 3 - direction (0 = DMA_TO_DEVICE, 1 = DMA_FROM_DEVICE
* bit 4:31 - reserved */
B3D_REG_EC220_DMA_STS = 0x8008,
};
enum b3dfg_buffer_state {
B3DFG_BUFFER_POLLED = 0,
B3DFG_BUFFER_PENDING,
B3DFG_BUFFER_POPULATED,
};
struct b3dfg_buffer {
unsigned char *frame[B3DFG_FRAMES_PER_BUFFER];
struct list_head list;
u8 state;
};
struct b3dfg_dev {
/* no protection needed: all finalized at initialization time */
struct pci_dev *pdev;
struct cdev chardev;
struct device *dev;
void __iomem *regs;
unsigned int frame_size;
/*
* Protects buffer state, including buffer_queue, triplet_ready,
* cur_dma_frame_idx & cur_dma_frame_addr.
*/
spinlock_t buffer_lock;
struct b3dfg_buffer *buffers;
struct list_head buffer_queue;
/* Last frame in triplet transferred (-1 if none). */
int cur_dma_frame_idx;
/* Current frame's address for DMA. */
dma_addr_t cur_dma_frame_addr;
/*
* Protects cstate_tstamp.
* Nests inside buffer_lock.
*/
spinlock_t cstate_lock;
unsigned long cstate_tstamp;
/*
* Protects triplets_dropped.
* Nests inside buffers_lock.
*/
spinlock_t triplets_dropped_lock;
unsigned int triplets_dropped;
wait_queue_head_t buffer_waitqueue;
unsigned int transmission_enabled:1;
unsigned int triplet_ready:1;
};
static u8 b3dfg_devices[B3DFG_MAX_DEVS];
static struct class *b3dfg_class;
static dev_t b3dfg_devt;
static const struct pci_device_id b3dfg_ids[] __devinitdata = {
{ PCI_DEVICE(0x0b3d, 0x0001) },
{ },
};
MODULE_DEVICE_TABLE(pci, b3dfg_ids);
/***** user-visible types *****/
struct b3dfg_poll {
int buffer_idx;
unsigned int triplets_dropped;
};
struct b3dfg_wait {
int buffer_idx;
unsigned int timeout;
unsigned int triplets_dropped;
};
/**** register I/O ****/
static u32 b3dfg_read32(struct b3dfg_dev *fgdev, u16 reg)
{
return ioread32(fgdev->regs + reg);
}
static void b3dfg_write32(struct b3dfg_dev *fgdev, u16 reg, u32 value)
{
iowrite32(value, fgdev->regs + reg);
}
/**** buffer management ****/
/*
* Program EC220 for transfer of a specific frame.
* Called with buffer_lock held.
*/
static int setup_frame_transfer(struct b3dfg_dev *fgdev,
struct b3dfg_buffer *buf, int frame)
{
unsigned char *frm_addr;
dma_addr_t frm_addr_dma;
unsigned int frm_size = fgdev->frame_size;
frm_addr = buf->frame[frame];
frm_addr_dma = pci_map_single(fgdev->pdev, frm_addr,
frm_size, PCI_DMA_FROMDEVICE);
if (pci_dma_mapping_error(fgdev->pdev, frm_addr_dma))
return -ENOMEM;
fgdev->cur_dma_frame_addr = frm_addr_dma;
fgdev->cur_dma_frame_idx = frame;
b3dfg_write32(fgdev, B3D_REG_EC220_DMA_ADDR,
cpu_to_le32(frm_addr_dma));
b3dfg_write32(fgdev, B3D_REG_EC220_TRF_SIZE,
cpu_to_le32(frm_size >> 2));
b3dfg_write32(fgdev, B3D_REG_EC220_DMA_STS, 0xf);
return 0;
}
/* Caller should hold buffer lock */
static void dequeue_all_buffers(struct b3dfg_dev *fgdev)
{
int i;
for (i = 0; i < b3dfg_nbuf; i++) {
struct b3dfg_buffer *buf = &fgdev->buffers[i];
buf->state = B3DFG_BUFFER_POLLED;
list_del_init(&buf->list);
}
}
/* queue a buffer to receive data */
static int queue_buffer(struct b3dfg_dev *fgdev, int bufidx)
{
struct device *dev = &fgdev->pdev->dev;
struct b3dfg_buffer *buf;
unsigned long flags;
int r = 0;
spin_lock_irqsave(&fgdev->buffer_lock, flags);
if (bufidx < 0 || bufidx >= b3dfg_nbuf) {
dev_dbg(dev, "Invalid buffer index, %d\n", bufidx);
r = -ENOENT;
goto out;
}
buf = &fgdev->buffers[bufidx];
if (unlikely(buf->state == B3DFG_BUFFER_PENDING)) {
dev_dbg(dev, "buffer %d is already queued\n", bufidx);
r = -EINVAL;
goto out;
}
buf->state = B3DFG_BUFFER_PENDING;
list_add_tail(&buf->list, &fgdev->buffer_queue);
if (fgdev->transmission_enabled && fgdev->triplet_ready) {
dev_dbg(dev, "triplet is ready, pushing immediately\n");
fgdev->triplet_ready = 0;
r = setup_frame_transfer(fgdev, buf, 0);
if (r)
dev_err(dev, "unable to map DMA buffer\n");
}
out:
spin_unlock_irqrestore(&fgdev->buffer_lock, flags);
return r;
}
/* non-blocking buffer poll. returns 1 if data is present in the buffer,
* 0 otherwise */
static int poll_buffer(struct b3dfg_dev *fgdev, void __user *arg)
{
struct device *dev = &fgdev->pdev->dev;
struct b3dfg_poll p;
struct b3dfg_buffer *buf;
unsigned long flags;
int r = 1;
int arg_out = 0;
if (copy_from_user(&p, arg, sizeof(p)))
return -EFAULT;
if (unlikely(!fgdev->transmission_enabled)) {
dev_dbg(dev, "cannot poll, transmission disabled\n");
return -EINVAL;
}
if (p.buffer_idx < 0 || p.buffer_idx >= b3dfg_nbuf)
return -ENOENT;
buf = &fgdev->buffers[p.buffer_idx];
spin_lock_irqsave(&fgdev->buffer_lock, flags);
if (likely(buf->state == B3DFG_BUFFER_POPULATED)) {
arg_out = 1;
buf->state = B3DFG_BUFFER_POLLED;
/* IRQs already disabled by spin_lock_irqsave above. */
spin_lock(&fgdev->triplets_dropped_lock);
p.triplets_dropped = fgdev->triplets_dropped;
fgdev->triplets_dropped = 0;
spin_unlock(&fgdev->triplets_dropped_lock);
} else {
r = 0;
}
spin_unlock_irqrestore(&fgdev->buffer_lock, flags);
if (arg_out && copy_to_user(arg, &p, sizeof(p)))
r = -EFAULT;
return r;
}
static unsigned long get_cstate_change(struct b3dfg_dev *fgdev)
{
unsigned long flags, when;
spin_lock_irqsave(&fgdev->cstate_lock, flags);
when = fgdev->cstate_tstamp;
spin_unlock_irqrestore(&fgdev->cstate_lock, flags);
return when;
}
static int is_event_ready(struct b3dfg_dev *fgdev, struct b3dfg_buffer *buf,
unsigned long when)
{
int result;
unsigned long flags;
spin_lock_irqsave(&fgdev->buffer_lock, flags);
spin_lock(&fgdev->cstate_lock);
result = (!fgdev->transmission_enabled ||
buf->state == B3DFG_BUFFER_POPULATED ||
when != fgdev->cstate_tstamp);
spin_unlock(&fgdev->cstate_lock);
spin_unlock_irqrestore(&fgdev->buffer_lock, flags);
return result;
}
/* sleep until a specific buffer becomes populated */
static int wait_buffer(struct b3dfg_dev *fgdev, void __user *arg)
{
struct device *dev = &fgdev->pdev->dev;
struct b3dfg_wait w;
struct b3dfg_buffer *buf;
unsigned long flags, when;
int r;
if (copy_from_user(&w, arg, sizeof(w)))
return -EFAULT;
if (!fgdev->transmission_enabled) {
dev_dbg(dev, "cannot wait, transmission disabled\n");
return -EINVAL;
}
if (w.buffer_idx < 0 || w.buffer_idx >= b3dfg_nbuf)
return -ENOENT;
buf = &fgdev->buffers[w.buffer_idx];
spin_lock_irqsave(&fgdev->buffer_lock, flags);
if (buf->state == B3DFG_BUFFER_POPULATED) {
r = w.timeout;
goto out_triplets_dropped;
}
spin_unlock_irqrestore(&fgdev->buffer_lock, flags);
when = get_cstate_change(fgdev);
if (w.timeout > 0) {
r = wait_event_interruptible_timeout(fgdev->buffer_waitqueue,
is_event_ready(fgdev, buf, when),
(w.timeout * HZ) / 1000);
if (unlikely(r < 0))
goto out;
w.timeout = r * 1000 / HZ;
} else {
r = wait_event_interruptible(fgdev->buffer_waitqueue,
is_event_ready(fgdev, buf, when));
if (unlikely(r)) {
r = -ERESTARTSYS;
goto out;
}
}
/* TODO: Inform the user via field(s) in w? */
if (!fgdev->transmission_enabled || when != get_cstate_change(fgdev)) {
r = -EINVAL;
goto out;
}
spin_lock_irqsave(&fgdev->buffer_lock, flags);
if (buf->state != B3DFG_BUFFER_POPULATED) {
r = -ETIMEDOUT;
goto out_unlock;
}
buf->state = B3DFG_BUFFER_POLLED;
out_triplets_dropped:
/* IRQs already disabled by spin_lock_irqsave above. */
spin_lock(&fgdev->triplets_dropped_lock);
w.triplets_dropped = fgdev->triplets_dropped;
fgdev->triplets_dropped = 0;
spin_unlock(&fgdev->triplets_dropped_lock);
out_unlock:
spin_unlock_irqrestore(&fgdev->buffer_lock, flags);
if (copy_to_user(arg, &w, sizeof(w)))
r = -EFAULT;
out:
return r;
}
/* mmap page fault handler */
static int b3dfg_vma_fault(struct vm_area_struct *vma,
struct vm_fault *vmf)
{
struct b3dfg_dev *fgdev = vma->vm_file->private_data;
unsigned long off = vmf->pgoff << PAGE_SHIFT;
unsigned int frame_size = fgdev->frame_size;
unsigned int buf_size = frame_size * B3DFG_FRAMES_PER_BUFFER;
unsigned char *addr;
/* determine which buffer the offset lies within */
unsigned int buf_idx = off / buf_size;
/* and the offset into the buffer */
unsigned int buf_off = off % buf_size;
/* determine which frame inside the buffer the offset lies in */
unsigned int frm_idx = buf_off / frame_size;
/* and the offset into the frame */
unsigned int frm_off = buf_off % frame_size;
if (unlikely(buf_idx >= b3dfg_nbuf))
return VM_FAULT_SIGBUS;
addr = fgdev->buffers[buf_idx].frame[frm_idx] + frm_off;
vm_insert_pfn(vma, (unsigned long)vmf->virtual_address,
virt_to_phys(addr) >> PAGE_SHIFT);
return VM_FAULT_NOPAGE;
}
static struct vm_operations_struct b3dfg_vm_ops = {
.fault = b3dfg_vma_fault,
};
static int get_wand_status(struct b3dfg_dev *fgdev, int __user *arg)
{
u32 wndstat = b3dfg_read32(fgdev, B3D_REG_WAND_STS);
dev_dbg(&fgdev->pdev->dev, "wand status %x\n", wndstat);
return __put_user(wndstat & 0x1, arg);
}
static int enable_transmission(struct b3dfg_dev *fgdev)
{
u16 command;
unsigned long flags;
struct device *dev = &fgdev->pdev->dev;
dev_dbg(dev, "enable transmission\n");
/* check the cable is plugged in. */
if (!b3dfg_read32(fgdev, B3D_REG_WAND_STS)) {
dev_dbg(dev, "cannot start transmission without wand\n");
return -EINVAL;
}
/*
* Check we're a bus master.
* TODO: I think we can remove this having added the pci_set_master call
*/
pci_read_config_word(fgdev->pdev, PCI_COMMAND, &command);
if (!(command & PCI_COMMAND_MASTER)) {
dev_err(dev, "not a bus master, force-enabling\n");
pci_write_config_word(fgdev->pdev, PCI_COMMAND,
command | PCI_COMMAND_MASTER);
}
spin_lock_irqsave(&fgdev->buffer_lock, flags);
/* Handle racing enable_transmission calls. */
if (fgdev->transmission_enabled) {
spin_unlock_irqrestore(&fgdev->buffer_lock, flags);
goto out;
}
spin_lock(&fgdev->triplets_dropped_lock);
fgdev->triplets_dropped = 0;
spin_unlock(&fgdev->triplets_dropped_lock);
fgdev->triplet_ready = 0;
fgdev->cur_dma_frame_idx = -1;
fgdev->transmission_enabled = 1;
spin_unlock_irqrestore(&fgdev->buffer_lock, flags);
/* Enable DMA and cable status interrupts. */
b3dfg_write32(fgdev, B3D_REG_HW_CTRL, 0x03);
out:
return 0;
}
static void disable_transmission(struct b3dfg_dev *fgdev)
{
struct device *dev = &fgdev->pdev->dev;
unsigned long flags;
u32 tmp;
dev_dbg(dev, "disable transmission\n");
/* guarantee that no more interrupts will be serviced */
spin_lock_irqsave(&fgdev->buffer_lock, flags);
fgdev->transmission_enabled = 0;
b3dfg_write32(fgdev, B3D_REG_HW_CTRL, 0);
/* FIXME: temporary debugging only. if the board stops transmitting,
* hitting ctrl+c and seeing this message is useful for determining
* the state of the board. */
tmp = b3dfg_read32(fgdev, B3D_REG_DMA_STS);
dev_dbg(dev, "DMA_STS reads %x after TX stopped\n", tmp);
dequeue_all_buffers(fgdev);
spin_unlock_irqrestore(&fgdev->buffer_lock, flags);
wake_up_interruptible(&fgdev->buffer_waitqueue);
}
static int set_transmission(struct b3dfg_dev *fgdev, int enabled)
{
int res = 0;
if (enabled && !fgdev->transmission_enabled)
res = enable_transmission(fgdev);
else if (!enabled && fgdev->transmission_enabled)
disable_transmission(fgdev);
return res;
}
/* Called in interrupt context. */
static void handle_cstate_unplug(struct b3dfg_dev *fgdev)
{
/* Disable all interrupts. */
b3dfg_write32(fgdev, B3D_REG_HW_CTRL, 0);
/* Stop transmission. */
spin_lock(&fgdev->buffer_lock);
fgdev->transmission_enabled = 0;
fgdev->cur_dma_frame_idx = -1;
fgdev->triplet_ready = 0;
if (fgdev->cur_dma_frame_addr) {
pci_unmap_single(fgdev->pdev, fgdev->cur_dma_frame_addr,
fgdev->frame_size, PCI_DMA_FROMDEVICE);
fgdev->cur_dma_frame_addr = 0;
}
dequeue_all_buffers(fgdev);
spin_unlock(&fgdev->buffer_lock);
}
/* Called in interrupt context. */
static void handle_cstate_change(struct b3dfg_dev *fgdev)
{
u32 cstate = b3dfg_read32(fgdev, B3D_REG_WAND_STS);
unsigned long when;
struct device *dev = &fgdev->pdev->dev;
dev_dbg(dev, "cable state change: %u\n", cstate);
/*
* When the wand is unplugged we reset our state. The hardware will
* have done the same internally.
*
* Note we should never see a cable *plugged* event, as interrupts
* should only be enabled when transmitting, which requires the cable
* to be plugged. If we do see one it probably means the cable has been
* unplugged and re-plugged very rapidly. Possibly because it has a
* broken wire and is momentarily losing contact.
*
* TODO: At the moment if you plug in the cable then enable transmission
* the hardware will raise a couple of spurious interrupts, so
* just ignore them for now.
*
* Once the hardware is fixed we should complain and treat it as an
* unplug. Or at least track how frequently it is happening and do
* so if too many come in.
*/
if (cstate) {
dev_warn(dev, "ignoring unexpected plug event\n");
return;
}
handle_cstate_unplug(fgdev);
/*
* Record cable state change timestamp & wake anyone waiting
* on a cable state change. Be paranoid about ensuring events
* are not missed if we somehow get two interrupts in a jiffy.
*/
spin_lock(&fgdev->cstate_lock);
when = jiffies_64;
if (when <= fgdev->cstate_tstamp)
when = fgdev->cstate_tstamp + 1;
fgdev->cstate_tstamp = when;
wake_up_interruptible(&fgdev->buffer_waitqueue);
spin_unlock(&fgdev->cstate_lock);
}
/* Called with buffer_lock held. */
static void transfer_complete(struct b3dfg_dev *fgdev)
{
struct b3dfg_buffer *buf;
struct device *dev = &fgdev->pdev->dev;
pci_unmap_single(fgdev->pdev, fgdev->cur_dma_frame_addr,
fgdev->frame_size, PCI_DMA_FROMDEVICE);
fgdev->cur_dma_frame_addr = 0;
buf = list_entry(fgdev->buffer_queue.next, struct b3dfg_buffer, list);
dev_dbg(dev, "handle frame completion\n");
if (fgdev->cur_dma_frame_idx == B3DFG_FRAMES_PER_BUFFER - 1) {
/* last frame of that triplet completed */
dev_dbg(dev, "triplet completed\n");
buf->state = B3DFG_BUFFER_POPULATED;
list_del_init(&buf->list);
wake_up_interruptible(&fgdev->buffer_waitqueue);
}
}
/*
* Called with buffer_lock held.
*
* Note that idx is the (1-based) *next* frame to be transferred, while
* cur_dma_frame_idx is the (0-based) *last* frame to have been transferred (or
* -1 if none). Thus there should be a difference of 2 between them.
*/
static bool setup_next_frame_transfer(struct b3dfg_dev *fgdev, int idx)
{
struct b3dfg_buffer *buf;
struct device *dev = &fgdev->pdev->dev;
bool need_ack = 1;
dev_dbg(dev, "program DMA transfer for next frame: %d\n", idx);
buf = list_entry(fgdev->buffer_queue.next, struct b3dfg_buffer, list);
if (idx == fgdev->cur_dma_frame_idx + 2) {
if (setup_frame_transfer(fgdev, buf, idx - 1))
dev_err(dev, "unable to map DMA buffer\n");
need_ack = 0;
} else {
dev_err(dev, "frame mismatch, got %d, expected %d\n",
idx, fgdev->cur_dma_frame_idx + 2);
/* FIXME: handle dropped triplets here */
}
return need_ack;
}
static irqreturn_t b3dfg_intr(int irq, void *dev_id)
{
struct b3dfg_dev *fgdev = dev_id;
struct device *dev = &fgdev->pdev->dev;
u32 sts;
u8 dropped;
bool need_ack = 1;
irqreturn_t res = IRQ_HANDLED;
sts = b3dfg_read32(fgdev, B3D_REG_DMA_STS);
if (unlikely(sts == 0)) {
dev_warn(dev, "ignore interrupt, DMA status is 0\n");
res = IRQ_NONE;
goto out;
}
if (unlikely(!fgdev->transmission_enabled)) {
dev_warn(dev, "ignore interrupt, TX disabled\n");
res = IRQ_HANDLED;
goto out;
}
/* Handle dropped frames, as reported by the hardware. */
dropped = (sts >> 8) & 0xff;
dev_dbg(dev, "intr: DMA_STS=%08x (drop=%d comp=%d next=%d)\n",
sts, dropped, !!(sts & 0x4), sts & 0x3);
if (unlikely(dropped > 0)) {
spin_lock(&fgdev->triplets_dropped_lock);
fgdev->triplets_dropped += dropped;
spin_unlock(&fgdev->triplets_dropped_lock);
}
/* Handle a cable state change (i.e. the wand being unplugged). */
if (sts & 0x08) {
handle_cstate_change(fgdev);
goto out;
}
spin_lock(&fgdev->buffer_lock);
if (unlikely(list_empty(&fgdev->buffer_queue))) {
/* FIXME need more sanity checking here */
dev_info(dev, "buffer not ready for next transfer\n");
fgdev->triplet_ready = 1;
goto out_unlock;
}
/* Has a frame transfer been completed? */
if (sts & 0x4) {
u32 dma_status = b3dfg_read32(fgdev, B3D_REG_EC220_DMA_STS);
/* Check for DMA errors reported by the hardware. */
if (unlikely(dma_status & 0x1)) {
dev_err(dev, "EC220 error: %08x\n", dma_status);
/* FIXME flesh out error handling */
goto out_unlock;
}
/* Sanity check, we should have a frame index at this point. */
if (unlikely(fgdev->cur_dma_frame_idx == -1)) {
dev_err(dev, "completed but no last idx?\n");
/* FIXME flesh out error handling */
goto out_unlock;
}
transfer_complete(fgdev);
}
/* Is there another frame transfer pending? */
if (sts & 0x3)
need_ack = setup_next_frame_transfer(fgdev, sts & 0x3);
else
fgdev->cur_dma_frame_idx = -1;
out_unlock:
spin_unlock(&fgdev->buffer_lock);
out:
if (need_ack) {
dev_dbg(dev, "acknowledging interrupt\n");
b3dfg_write32(fgdev, B3D_REG_EC220_DMA_STS, 0x0b);
}
return res;
}
static int b3dfg_open(struct inode *inode, struct file *filp)
{
struct b3dfg_dev *fgdev =
container_of(inode->i_cdev, struct b3dfg_dev, chardev);
dev_dbg(&fgdev->pdev->dev, "open\n");
filp->private_data = fgdev;
return 0;
}
static int b3dfg_release(struct inode *inode, struct file *filp)
{
struct b3dfg_dev *fgdev = filp->private_data;
dev_dbg(&fgdev->pdev->dev, "release\n");
disable_transmission(fgdev);
return 0;
}
static long b3dfg_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct b3dfg_dev *fgdev = filp->private_data;
switch (cmd) {
case B3DFG_IOCGFRMSZ:
return __put_user(fgdev->frame_size, (int __user *) arg);
case B3DFG_IOCGWANDSTAT:
return get_wand_status(fgdev, (int __user *) arg);
case B3DFG_IOCTTRANS:
return set_transmission(fgdev, (int) arg);
case B3DFG_IOCTQUEUEBUF:
return queue_buffer(fgdev, (int) arg);
case B3DFG_IOCTPOLLBUF:
return poll_buffer(fgdev, (void __user *) arg);
case B3DFG_IOCTWAITBUF:
return wait_buffer(fgdev, (void __user *) arg);
default:
dev_dbg(&fgdev->pdev->dev, "unrecognised ioctl %x\n", cmd);
return -EINVAL;
}
}
static unsigned int b3dfg_poll(struct file *filp, poll_table *poll_table)
{
struct b3dfg_dev *fgdev = filp->private_data;
unsigned long flags, when;
int i;
int r = 0;
when = get_cstate_change(fgdev);
poll_wait(filp, &fgdev->buffer_waitqueue, poll_table);
spin_lock_irqsave(&fgdev->buffer_lock, flags);
for (i = 0; i < b3dfg_nbuf; i++) {
if (fgdev->buffers[i].state == B3DFG_BUFFER_POPULATED) {
r = POLLIN | POLLRDNORM;
break;
}
}
spin_unlock_irqrestore(&fgdev->buffer_lock, flags);
/* TODO: Confirm this is how we want to communicate the change. */
if (!fgdev->transmission_enabled || when != get_cstate_change(fgdev))
r = POLLERR;
return r;
}
static int b3dfg_mmap(struct file *filp, struct vm_area_struct *vma)
{
struct b3dfg_dev *fgdev = filp->private_data;
unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
unsigned long vsize = vma->vm_end - vma->vm_start;
unsigned long bufdatalen = b3dfg_nbuf * fgdev->frame_size * 3;
unsigned long psize = bufdatalen - offset;
int r = 0;
if (vsize <= psize) {
vma->vm_flags |= VM_IO | VM_RESERVED | VM_CAN_NONLINEAR |
VM_PFNMAP;
vma->vm_ops = &b3dfg_vm_ops;
} else {
r = -EINVAL;
}
return r;
}
static struct file_operations b3dfg_fops = {
.owner = THIS_MODULE,
.open = b3dfg_open,
.release = b3dfg_release,
.unlocked_ioctl = b3dfg_ioctl,
.poll = b3dfg_poll,
.mmap = b3dfg_mmap,
};
static void free_all_frame_buffers(struct b3dfg_dev *fgdev)
{
int i, j;
for (i = 0; i < b3dfg_nbuf; i++)
for (j = 0; j < B3DFG_FRAMES_PER_BUFFER; j++)
kfree(fgdev->buffers[i].frame[j]);
kfree(fgdev->buffers);
}
/* initialize device and any data structures. called before any interrupts
* are enabled. */
static int b3dfg_init_dev(struct b3dfg_dev *fgdev)
{
int i, j;
u32 frm_size = b3dfg_read32(fgdev, B3D_REG_FRM_SIZE);
/* Disable interrupts. In abnormal circumstances (e.g. after a crash)
* the board may still be transmitting from the previous session. If we
* ensure that interrupts are disabled before we later enable them, we
* are sure to capture a triplet from the start, rather than starting
* from frame 2 or 3. Disabling interrupts causes the FG to throw away
* all buffered data and stop buffering more until interrupts are
* enabled again.
*/
b3dfg_write32(fgdev, B3D_REG_HW_CTRL, 0);
fgdev->frame_size = frm_size * 4096;
fgdev->buffers = kzalloc(sizeof(struct b3dfg_buffer) * b3dfg_nbuf,
GFP_KERNEL);
if (!fgdev->buffers)
goto err_no_buf;
for (i = 0; i < b3dfg_nbuf; i++) {
struct b3dfg_buffer *buf = &fgdev->buffers[i];
for (j = 0; j < B3DFG_FRAMES_PER_BUFFER; j++) {
buf->frame[j] = kmalloc(fgdev->frame_size, GFP_KERNEL);
if (!buf->frame[j])
goto err_no_mem;
}
INIT_LIST_HEAD(&buf->list);
}
INIT_LIST_HEAD(&fgdev->buffer_queue);
init_waitqueue_head(&fgdev->buffer_waitqueue);
spin_lock_init(&fgdev->buffer_lock);
spin_lock_init(&fgdev->cstate_lock);
spin_lock_init(&fgdev->triplets_dropped_lock);
return 0;
err_no_mem:
free_all_frame_buffers(fgdev);
err_no_buf:
return -ENOMEM;
}
/* find next free minor number, returns -1 if none are availabile */
static int get_free_minor(void)
{
int i;
for (i = 0; i < B3DFG_MAX_DEVS; i++) {
if (b3dfg_devices[i] == 0)
return i;
}
return -1;
}
static int __devinit b3dfg_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
struct b3dfg_dev *fgdev = kzalloc(sizeof(*fgdev), GFP_KERNEL);
int r = 0;
int minor = get_free_minor();
dev_t devno = MKDEV(MAJOR(b3dfg_devt), minor);
unsigned long res_len;
resource_size_t res_base;
if (fgdev == NULL)
return -ENOMEM;
if (minor < 0) {
dev_err(&pdev->dev, "too many devices found!\n");
r = -EIO;
goto err_free;
}
b3dfg_devices[minor] = 1;
dev_info(&pdev->dev, "probe device with IRQ %d\n", pdev->irq);
cdev_init(&fgdev->chardev, &b3dfg_fops);
fgdev->chardev.owner = THIS_MODULE;
r = cdev_add(&fgdev->chardev, devno, 1);
if (r) {
dev_err(&pdev->dev, "cannot add char device\n");
goto err_release_minor;
}
fgdev->dev = device_create(
b3dfg_class,
&pdev->dev,
devno,
dev_get_drvdata(&pdev->dev),
DRIVER_NAME "%d", minor);
if (IS_ERR(fgdev->dev)) {
dev_err(&pdev->dev, "cannot create device\n");
r = PTR_ERR(fgdev->dev);
goto err_del_cdev;
}
r = pci_enable_device(pdev);
if (r) {
dev_err(&pdev->dev, "cannot enable PCI device\n");
goto err_dev_unreg;
}
res_len = pci_resource_len(pdev, B3DFG_BAR_REGS);
if (res_len != B3DFG_REGS_LENGTH) {
dev_err(&pdev->dev, "invalid register resource size\n");
r = -EIO;
goto err_disable;
}
if (pci_resource_flags(pdev, B3DFG_BAR_REGS)
!= (IORESOURCE_MEM | IORESOURCE_SIZEALIGN)) {
dev_err(&pdev->dev, "invalid resource flags\n");
r = -EIO;
goto err_disable;
}
r = pci_request_regions(pdev, DRIVER_NAME);
if (r) {
dev_err(&pdev->dev, "cannot obtain PCI resources\n");
goto err_disable;
}
pci_set_master(pdev);
r = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
if (r) {
dev_err(&pdev->dev, "no usable DMA configuration\n");
goto err_free_res;
}
res_base = pci_resource_start(pdev, B3DFG_BAR_REGS);
fgdev->regs = ioremap_nocache(res_base, res_len);
if (!fgdev->regs) {
dev_err(&pdev->dev, "regs ioremap failed\n");
r = -EIO;
goto err_free_res;
}
fgdev->pdev = pdev;
pci_set_drvdata(pdev, fgdev);
r = b3dfg_init_dev(fgdev);
if (r < 0) {
dev_err(&pdev->dev, "failed to initalize device\n");
goto err_unmap;
}
r = request_irq(pdev->irq, b3dfg_intr, IRQF_SHARED, DRIVER_NAME, fgdev);
if (r) {
dev_err(&pdev->dev, "couldn't request irq %d\n", pdev->irq);
goto err_free_bufs;
}
return 0;
err_free_bufs:
free_all_frame_buffers(fgdev);
err_unmap:
iounmap(fgdev->regs);
err_free_res:
pci_release_regions(pdev);
err_disable:
pci_disable_device(pdev);
err_dev_unreg:
device_destroy(b3dfg_class, devno);
err_del_cdev:
cdev_del(&fgdev->chardev);
err_release_minor:
b3dfg_devices[minor] = 0;
err_free:
kfree(fgdev);
return r;
}
static void __devexit b3dfg_remove(struct pci_dev *pdev)
{
struct b3dfg_dev *fgdev = pci_get_drvdata(pdev);
unsigned int minor = MINOR(fgdev->chardev.dev);
dev_dbg(&pdev->dev, "remove\n");
free_irq(pdev->irq, fgdev);
iounmap(fgdev->regs);
pci_release_regions(pdev);
pci_disable_device(pdev);
device_destroy(b3dfg_class, MKDEV(MAJOR(b3dfg_devt), minor));
cdev_del(&fgdev->chardev);
free_all_frame_buffers(fgdev);
kfree(fgdev);
b3dfg_devices[minor] = 0;
}
static struct pci_driver b3dfg_driver = {
.name = DRIVER_NAME,
.id_table = b3dfg_ids,
.probe = b3dfg_probe,
.remove = __devexit_p(b3dfg_remove),
};
static int __init b3dfg_module_init(void)
{
int r;
if (b3dfg_nbuf < 2) {
printk(KERN_ERR DRIVER_NAME
": buffer_count is out of range (must be >= 2)");
return -EINVAL;
}
printk(KERN_INFO DRIVER_NAME ": loaded\n");
b3dfg_class = class_create(THIS_MODULE, DRIVER_NAME);
if (IS_ERR(b3dfg_class))
return PTR_ERR(b3dfg_class);
r = alloc_chrdev_region(&b3dfg_devt, 0, B3DFG_MAX_DEVS, DRIVER_NAME);
if (r)
goto err1;
r = pci_register_driver(&b3dfg_driver);
if (r)
goto err2;
return r;
err2:
unregister_chrdev_region(b3dfg_devt, B3DFG_MAX_DEVS);
err1:
class_destroy(b3dfg_class);
return r;
}
static void __exit b3dfg_module_exit(void)
{
printk(KERN_INFO DRIVER_NAME ": unloaded\n");
pci_unregister_driver(&b3dfg_driver);
unregister_chrdev_region(b3dfg_devt, B3DFG_MAX_DEVS);
class_destroy(b3dfg_class);
}
module_init(b3dfg_module_init);
module_exit(b3dfg_module_exit);