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Subject[PATCH] firewire: core: add forgotten dummy driver methods, remove unused ones
There is an at least theoretic race condition in which .start_iso etc.
could still be called between when the dummy driver is bound to the card
and when the children devices are being shut down. Add dummy_start_iso
and friends.

On the other hand, .enable, .set_config_rom, .read_csr, write_csr do not
need to be implemented by the dummy driver, as commented.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
---
drivers/firewire/core-card.c | 64 +++++++++++++++++++++--------------
1 file changed, 38 insertions(+), 26 deletions(-)

Index: b/drivers/firewire/core-card.c
===================================================================
--- a/drivers/firewire/core-card.c
+++ b/drivers/firewire/core-card.c
@@ -552,15 +552,13 @@ EXPORT_SYMBOL(fw_card_add);
* as all IO to the card will be handled (and failed) by the dummy driver
* instead of calling into the module. Only functions for iso context
* shutdown still need to be provided by the card driver.
+ *
+ * .read/write_csr() should never be called anymore after the dummy driver
+ * was bound since they are only used within request handler context.
+ * .set_config_rom() is never called since the card is taken out of card_list
+ * before switching to the dummy driver.
*/

-static int dummy_enable(struct fw_card *card,
- const __be32 *config_rom, size_t length)
-{
- BUG();
- return -1;
-}
-
static int dummy_read_phy_reg(struct fw_card *card, int address)
{
return -ENODEV;
@@ -572,17 +570,6 @@ static int dummy_update_phy_reg(struct f
return -ENODEV;
}

-static int dummy_set_config_rom(struct fw_card *card,
- const __be32 *config_rom, size_t length)
-{
- /*
- * We take the card out of card_list before setting the dummy
- * driver, so this should never get called.
- */
- BUG();
- return -1;
-}
-
static void dummy_send_request(struct fw_card *card, struct fw_packet *packet)
{
packet->callback(packet, card, RCODE_CANCELLED);
@@ -604,15 +591,40 @@ static int dummy_enable_phys_dma(struct
return -ENODEV;
}

+static struct fw_iso_context *dummy_allocate_iso_context(struct fw_card *card,
+ int type, int channel, size_t header_size)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static int dummy_start_iso(struct fw_iso_context *ctx,
+ s32 cycle, u32 sync, u32 tags)
+{
+ return -ENODEV;
+}
+
+static int dummy_set_iso_channels(struct fw_iso_context *ctx, u64 *channels)
+{
+ return -ENODEV;
+}
+
+static int dummy_queue_iso(struct fw_iso_context *ctx, struct fw_iso_packet *p,
+ struct fw_iso_buffer *buffer, unsigned long payload)
+{
+ return -ENODEV;
+}
+
static const struct fw_card_driver dummy_driver_template = {
- .enable = dummy_enable,
- .read_phy_reg = dummy_read_phy_reg,
- .update_phy_reg = dummy_update_phy_reg,
- .set_config_rom = dummy_set_config_rom,
- .send_request = dummy_send_request,
- .cancel_packet = dummy_cancel_packet,
- .send_response = dummy_send_response,
- .enable_phys_dma = dummy_enable_phys_dma,
+ .read_phy_reg = dummy_read_phy_reg,
+ .update_phy_reg = dummy_update_phy_reg,
+ .send_request = dummy_send_request,
+ .send_response = dummy_send_response,
+ .cancel_packet = dummy_cancel_packet,
+ .enable_phys_dma = dummy_enable_phys_dma,
+ .allocate_iso_context = dummy_allocate_iso_context,
+ .start_iso = dummy_start_iso,
+ .set_iso_channels = dummy_set_iso_channels,
+ .queue_iso = dummy_queue_iso,
};

void fw_card_release(struct kref *kref)
--
Stefan Richter
-=====-==-=- =--- ----=
http://arcgraph.de/sr/


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