firewire: add CSR CYCLE_TIME write support

The specification requires that CYCLE_TIME is writable so that it can be
initialized, so we better implement it.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/firewire/core-transaction.c b/drivers/firewire/core-transaction.c
index 9a7d3ec23f2..e3925f67ec1 100644
--- a/drivers/firewire/core-transaction.c
+++ b/drivers/firewire/core-transaction.c
@@ -1097,6 +1097,9 @@ static void handle_registers(struct fw_card *card, struct fw_request *request,
                 if (TCODE_IS_READ_REQUEST(tcode) && length == 4)
                         *data = cpu_to_be32(card->driver->
                                         read_csr_reg(card, CSR_CYCLE_TIME));
+                else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
+                        card->driver->write_csr_reg(card, CSR_CYCLE_TIME,
+                                                    be32_to_cpu(*data));
                 else
                         rcode = RCODE_TYPE_ERROR;
                 break;