ALSA: dice: get clock capabilities

In preparation for sample rate selection support, ensure that the driver
knows about the device's clock capabilities.

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

1 files changed, 21 insertions, 2 deletions

diff --git a/sound/firewire/dice.c b/sound/firewire/dice.c
index 2d3a04ef9840..06fef4752d50 100644
--- a/sound/firewire/dice.c
+++ b/sound/firewire/dice.c
@@ -36,6 +36,7 @@ struct dice {
         struct mutex mutex;
         unsigned int global_offset;
         unsigned int rx_offset;
+        unsigned int clock_caps;
         struct fw_address_handler notification_handler;
         int owner_generation;
         int dev_lock_count; /* > 0 driver, < 0 userspace */
@@ -830,9 +831,10 @@ static int dice_interface_check(struct fw_unit *unit)
         return 0;
 }
 
-static int dice_init_offsets(struct dice *dice)
+static int dice_read_params(struct dice *dice)
 {
         __be32 pointers[6];
+        __be32 value;
         int err;
 
         err = snd_fw_transaction(dice->unit, TCODE_READ_BLOCK_REQUEST,
@@ -844,6 +846,23 @@ static int dice_init_offsets(struct dice *dice)
         dice->global_offset = be32_to_cpu(pointers[0]) * 4;
         dice->rx_offset = be32_to_cpu(pointers[4]) * 4;
 
+        /* some very old firmwares don't tell about their clock support */
+        if (be32_to_cpu(pointers[1]) * 4 >= GLOBAL_CLOCK_CAPABILITIES + 4) {
+                err = snd_fw_transaction(
+                                dice->unit, TCODE_READ_QUADLET_REQUEST,
+                                global_address(dice, GLOBAL_CLOCK_CAPABILITIES),
+                                &value, 4, 0);
+                if (err < 0)
+                        return err;
+                dice->clock_caps = be32_to_cpu(value);
+        } else {
+                /* this should be supported by any device */
+                dice->clock_caps = CLOCK_CAP_RATE_44100 |
+                                   CLOCK_CAP_RATE_48000 |
+                                   CLOCK_CAP_SOURCE_ARX1 |
+                                   CLOCK_CAP_SOURCE_INTERNAL;
+        }
+
         return 0;
 }
 
@@ -905,7 +924,7 @@ static int dice_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
         dice->unit = unit;
         init_waitqueue_head(&dice->hwdep_wait);
 
-        err = dice_init_offsets(dice);
+        err = dice_read_params(dice);
         if (err < 0)
                 goto err_mutex;