kernel-fxtec-pro1x/drivers/media/dvb/firewire/firedtv-fw.c
Clemens Ladisch db5d247ae8 firewire: fix use of multiple AV/C devices, allow multiple FCP listeners
Control of more than one AV/C device at once --- e.g. camcorders, tape
decks, audio devices, TV tuners --- failed or worked only unreliably,
depending on driver implementation.  This affected kernelspace and
userspace drivers alike and was caused by firewire-core's inability to
accept multiple registrations of FCP listeners.

The fix allows multiple address handlers to be registered for the FCP
command and response registers.  When a request for these registers is
received, all handlers are invoked, and the Firewire response is
generated by the core and not by any handler.

The cdev API does not change, i.e., userspace is still expected to send
a response for FCP requests; this response is silently ignored.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (changelog, rebased, whitespace)
2009-12-29 19:58:16 +01:00

368 lines
8.3 KiB
C

/*
* FireDTV driver -- firewire I/O backend
*/
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/firewire.h>
#include <linux/firewire-constants.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <asm/page.h>
#include <dvb_demux.h>
#include "firedtv.h"
static LIST_HEAD(node_list);
static DEFINE_SPINLOCK(node_list_lock);
static inline struct fw_device *device_of(struct firedtv *fdtv)
{
return fw_device(fdtv->device->parent);
}
static int node_req(struct firedtv *fdtv, u64 addr, void *data, size_t len,
int tcode)
{
struct fw_device *device = device_of(fdtv);
int rcode, generation = device->generation;
smp_rmb(); /* node_id vs. generation */
rcode = fw_run_transaction(device->card, tcode, device->node_id,
generation, device->max_speed, addr, data, len);
return rcode != RCODE_COMPLETE ? -EIO : 0;
}
static int node_lock(struct firedtv *fdtv, u64 addr, __be32 data[])
{
return node_req(fdtv, addr, data, 8, TCODE_LOCK_COMPARE_SWAP);
}
static int node_read(struct firedtv *fdtv, u64 addr, void *data)
{
return node_req(fdtv, addr, data, 4, TCODE_READ_QUADLET_REQUEST);
}
static int node_write(struct firedtv *fdtv, u64 addr, void *data, size_t len)
{
return node_req(fdtv, addr, data, len, TCODE_WRITE_BLOCK_REQUEST);
}
#define ISO_HEADER_SIZE 4
#define CIP_HEADER_SIZE 8
#define MPEG2_TS_HEADER_SIZE 4
#define MPEG2_TS_SOURCE_PACKET_SIZE (4 + 188)
#define MAX_PACKET_SIZE 1024 /* 776, rounded up to 2^n */
#define PACKETS_PER_PAGE (PAGE_SIZE / MAX_PACKET_SIZE)
#define N_PACKETS 64 /* buffer size */
#define N_PAGES DIV_ROUND_UP(N_PACKETS, PACKETS_PER_PAGE)
#define IRQ_INTERVAL 16
struct firedtv_receive_context {
struct fw_iso_context *context;
struct fw_iso_buffer buffer;
int interrupt_packet;
int current_packet;
char *pages[N_PAGES];
};
static int queue_iso(struct firedtv_receive_context *ctx, int index)
{
struct fw_iso_packet p;
p.payload_length = MAX_PACKET_SIZE;
p.interrupt = !(++ctx->interrupt_packet & (IRQ_INTERVAL - 1));
p.skip = 0;
p.header_length = ISO_HEADER_SIZE;
return fw_iso_context_queue(ctx->context, &p, &ctx->buffer,
index * MAX_PACKET_SIZE);
}
static void handle_iso(struct fw_iso_context *context, u32 cycle,
size_t header_length, void *header, void *data)
{
struct firedtv *fdtv = data;
struct firedtv_receive_context *ctx = fdtv->backend_data;
__be32 *h, *h_end;
int length, err, i = ctx->current_packet;
char *p, *p_end;
for (h = header, h_end = h + header_length / 4; h < h_end; h++) {
length = be32_to_cpup(h) >> 16;
if (unlikely(length > MAX_PACKET_SIZE)) {
dev_err(fdtv->device, "length = %d\n", length);
length = MAX_PACKET_SIZE;
}
p = ctx->pages[i / PACKETS_PER_PAGE]
+ (i % PACKETS_PER_PAGE) * MAX_PACKET_SIZE;
p_end = p + length;
for (p += CIP_HEADER_SIZE + MPEG2_TS_HEADER_SIZE; p < p_end;
p += MPEG2_TS_SOURCE_PACKET_SIZE)
dvb_dmx_swfilter_packets(&fdtv->demux, p, 1);
err = queue_iso(ctx, i);
if (unlikely(err))
dev_err(fdtv->device, "requeue failed\n");
i = (i + 1) & (N_PACKETS - 1);
}
ctx->current_packet = i;
}
static int start_iso(struct firedtv *fdtv)
{
struct firedtv_receive_context *ctx;
struct fw_device *device = device_of(fdtv);
int i, err;
ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
ctx->context = fw_iso_context_create(device->card,
FW_ISO_CONTEXT_RECEIVE, fdtv->isochannel,
device->max_speed, ISO_HEADER_SIZE, handle_iso, fdtv);
if (IS_ERR(ctx->context)) {
err = PTR_ERR(ctx->context);
goto fail_free;
}
err = fw_iso_buffer_init(&ctx->buffer, device->card,
N_PAGES, DMA_FROM_DEVICE);
if (err)
goto fail_context_destroy;
ctx->interrupt_packet = 0;
ctx->current_packet = 0;
for (i = 0; i < N_PAGES; i++)
ctx->pages[i] = page_address(ctx->buffer.pages[i]);
for (i = 0; i < N_PACKETS; i++) {
err = queue_iso(ctx, i);
if (err)
goto fail;
}
err = fw_iso_context_start(ctx->context, -1, 0,
FW_ISO_CONTEXT_MATCH_ALL_TAGS);
if (err)
goto fail;
fdtv->backend_data = ctx;
return 0;
fail:
fw_iso_buffer_destroy(&ctx->buffer, device->card);
fail_context_destroy:
fw_iso_context_destroy(ctx->context);
fail_free:
kfree(ctx);
return err;
}
static void stop_iso(struct firedtv *fdtv)
{
struct firedtv_receive_context *ctx = fdtv->backend_data;
fw_iso_context_stop(ctx->context);
fw_iso_buffer_destroy(&ctx->buffer, device_of(fdtv)->card);
fw_iso_context_destroy(ctx->context);
kfree(ctx);
}
static const struct firedtv_backend backend = {
.lock = node_lock,
.read = node_read,
.write = node_write,
.start_iso = start_iso,
.stop_iso = stop_iso,
};
static void handle_fcp(struct fw_card *card, struct fw_request *request,
int tcode, int destination, int source, int generation,
int speed, unsigned long long offset,
void *payload, size_t length, void *callback_data)
{
struct firedtv *f, *fdtv = NULL;
struct fw_device *device;
unsigned long flags;
int su;
if (length < 2 || (((u8 *)payload)[0] & 0xf0) != 0)
return;
su = ((u8 *)payload)[1] & 0x7;
spin_lock_irqsave(&node_list_lock, flags);
list_for_each_entry(f, &node_list, list) {
device = device_of(f);
if (device->generation != generation)
continue;
smp_rmb(); /* node_id vs. generation */
if (device->card == card &&
device->node_id == source &&
(f->subunit == su || (f->subunit == 0 && su == 0x7))) {
fdtv = f;
break;
}
}
spin_unlock_irqrestore(&node_list_lock, flags);
if (fdtv)
avc_recv(fdtv, payload, length);
}
static struct fw_address_handler fcp_handler = {
.length = CSR_FCP_END - CSR_FCP_RESPONSE,
.address_callback = handle_fcp,
};
static const struct fw_address_region fcp_region = {
.start = CSR_REGISTER_BASE + CSR_FCP_RESPONSE,
.end = CSR_REGISTER_BASE + CSR_FCP_END,
};
/* Adjust the template string if models with longer names appear. */
#define MAX_MODEL_NAME_LEN ((int)DIV_ROUND_UP(sizeof("FireDTV ????"), 4))
static size_t model_name(u32 *directory, __be32 *buffer)
{
struct fw_csr_iterator ci;
int i, length, key, value, last_key = 0;
u32 *block = NULL;
fw_csr_iterator_init(&ci, directory);
while (fw_csr_iterator_next(&ci, &key, &value)) {
if (last_key == CSR_MODEL &&
key == (CSR_DESCRIPTOR | CSR_LEAF))
block = ci.p - 1 + value;
last_key = key;
}
if (block == NULL)
return 0;
length = min((int)(block[0] >> 16) - 2, MAX_MODEL_NAME_LEN);
if (length <= 0)
return 0;
/* fast-forward to text string */
block += 3;
for (i = 0; i < length; i++)
buffer[i] = cpu_to_be32(block[i]);
return length * 4;
}
static int node_probe(struct device *dev)
{
struct firedtv *fdtv;
__be32 name[MAX_MODEL_NAME_LEN];
int name_len, err;
name_len = model_name(fw_unit(dev)->directory, name);
fdtv = fdtv_alloc(dev, &backend, (char *)name, name_len);
if (!fdtv)
return -ENOMEM;
err = fdtv_register_rc(fdtv, dev);
if (err)
goto fail_free;
spin_lock_irq(&node_list_lock);
list_add_tail(&fdtv->list, &node_list);
spin_unlock_irq(&node_list_lock);
err = avc_identify_subunit(fdtv);
if (err)
goto fail;
err = fdtv_dvb_register(fdtv);
if (err)
goto fail;
avc_register_remote_control(fdtv);
return 0;
fail:
spin_lock_irq(&node_list_lock);
list_del(&fdtv->list);
spin_unlock_irq(&node_list_lock);
fdtv_unregister_rc(fdtv);
fail_free:
kfree(fdtv);
return err;
}
static int node_remove(struct device *dev)
{
struct firedtv *fdtv = dev_get_drvdata(dev);
fdtv_dvb_unregister(fdtv);
spin_lock_irq(&node_list_lock);
list_del(&fdtv->list);
spin_unlock_irq(&node_list_lock);
fdtv_unregister_rc(fdtv);
kfree(fdtv);
return 0;
}
static void node_update(struct fw_unit *unit)
{
struct firedtv *fdtv = dev_get_drvdata(&unit->device);
if (fdtv->isochannel >= 0)
cmp_establish_pp_connection(fdtv, fdtv->subunit,
fdtv->isochannel);
}
static struct fw_driver fdtv_driver = {
.driver = {
.owner = THIS_MODULE,
.name = "firedtv",
.bus = &fw_bus_type,
.probe = node_probe,
.remove = node_remove,
},
.update = node_update,
.id_table = fdtv_id_table,
};
int __init fdtv_fw_init(void)
{
int ret;
ret = fw_core_add_address_handler(&fcp_handler, &fcp_region);
if (ret < 0)
return ret;
return driver_register(&fdtv_driver.driver);
}
void fdtv_fw_exit(void)
{
driver_unregister(&fdtv_driver.driver);
fw_core_remove_address_handler(&fcp_handler);
}