firewire: add read_csr_reg driver callback

To prepare for the following additions of more OHCI-implemented CSR
registers, replace the get_cycle_time driver callback with a generic
CSR register callback.

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

4 files changed, 20 insertions, 6 deletions

diff --git a/drivers/firewire/core-cdev.c b/drivers/firewire/core-cdev.c
index 50332b84f49a..2e62516a4b15 100644
--- a/drivers/firewire/core-cdev.c
+++ b/drivers/firewire/core-cdev.c
@@ -1044,7 +1044,7 @@ static int ioctl_get_cycle_timer2(struct client *client, union ioctl_arg *arg)
 
         local_irq_disable();
 
-        cycle_time = card->driver->get_cycle_time(card);
+        cycle_time = card->driver->read_csr_reg(card, CSR_CYCLE_TIME);
 
         switch (a->clk_id) {
         case CLOCK_REALTIME:      getnstimeofday(&ts);                   break;
diff --git a/drivers/firewire/core-transaction.c b/drivers/firewire/core-transaction.c
index 6971400b6354..a4d8109edec2 100644
--- a/drivers/firewire/core-transaction.c
+++ b/drivers/firewire/core-transaction.c
@@ -1025,7 +1025,8 @@ static void handle_registers(struct fw_card *card, struct fw_request *request,
 
         case CSR_CYCLE_TIME:
                 if (TCODE_IS_READ_REQUEST(tcode) && length == 4)
-                        *data = cpu_to_be32(card->driver->get_cycle_time(card));
+                        *data = cpu_to_be32(card->driver->
+                                        read_csr_reg(card, CSR_CYCLE_TIME));
                 else
                         rcode = RCODE_TYPE_ERROR;
                 break;
diff --git a/drivers/firewire/core.h b/drivers/firewire/core.h
index 25a72e57a0cd..c19e9873e433 100644
--- a/drivers/firewire/core.h
+++ b/drivers/firewire/core.h
@@ -75,7 +75,7 @@ struct fw_card_driver {
         int (*enable_phys_dma)(struct fw_card *card,
                                int node_id, int generation);
 
-        u32 (*get_cycle_time)(struct fw_card *card);
+        u32 (*read_csr_reg)(struct fw_card *card, int csr_offset);
 
         struct fw_iso_context *
         (*allocate_iso_context)(struct fw_card *card,
diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index 65b9bdb8541a..a8093a9a3fc8 100644
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -1939,9 +1939,8 @@ static u32 cycle_timer_ticks(u32 cycle_timer)
  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
  * execute, so we have enough precision to compute the ratio of the differences.)
  */
-static u32 ohci_get_cycle_time(struct fw_card *card)
+static u32 get_cycle_time(struct fw_ohci *ohci)
 {
-        struct fw_ohci *ohci = fw_ohci(card);
         u32 c0, c1, c2;
         u32 t0, t1, t2;
         s32 diff01, diff12;
@@ -1970,6 +1969,20 @@ static u32 ohci_get_cycle_time(struct fw_card *card)
         return c2;
 }
 
+static u32 ohci_read_csr_reg(struct fw_card *card, int csr_offset)
+{
+        struct fw_ohci *ohci = fw_ohci(card);
+
+        switch (csr_offset) {
+        case CSR_CYCLE_TIME:
+                return get_cycle_time(ohci);
+
+        default:
+                WARN_ON(1);
+                return 0;
+        }
+}
+
 static void copy_iso_headers(struct iso_context *ctx, void *p)
 {
         int i = ctx->header_length;
@@ -2407,7 +2420,7 @@ static const struct fw_card_driver ohci_driver = {
         .send_response          = ohci_send_response,
         .cancel_packet          = ohci_cancel_packet,
         .enable_phys_dma        = ohci_enable_phys_dma,
-        .get_cycle_time         = ohci_get_cycle_time,
+        .read_csr_reg           = ohci_read_csr_reg,
 
         .allocate_iso_context   = ohci_allocate_iso_context,
         .free_iso_context       = ohci_free_iso_context,