ALSA: dice: get clock capabilities
authorClemens Ladisch <clemens@ladisch.de>
Sun, 4 Dec 2011 20:47:00 +0000 (21:47 +0100)
committerClemens Ladisch <clemens@ladisch.de>
Sun, 20 Oct 2013 20:07:57 +0000 (22:07 +0200)
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>
sound/firewire/dice.c

index 2d3a04ef9840ef971e38ed6f86eea73437f234cf..06fef4752d500d27e95f46a850ff3cf764287ad5 100644 (file)
@@ -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;