diff options
Diffstat (limited to 'drivers/staging/b3dfg/b3dfg.c')
| -rw-r--r-- | drivers/staging/b3dfg/b3dfg.c | 1119 |
1 files changed, 1119 insertions, 0 deletions
diff --git a/drivers/staging/b3dfg/b3dfg.c b/drivers/staging/b3dfg/b3dfg.c new file mode 100644 index 00000000000..0348072b3ab --- /dev/null +++ b/drivers/staging/b3dfg/b3dfg.c @@ -0,0 +1,1119 @@ + /* + * 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/version.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)\n"); + +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); + if (buf) { + 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); + } + } else { + dev_err(dev, "got frame but no buffer!\n"); + } +} + +/* + * 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 (buf) { + 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 */ + } + } else { + dev_err(dev, "cannot setup DMA, no buffer\n"); + } + + 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_32BIT_MASK); + 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); |