ALSA: dice: get rate-dependent parameters

In preparation for sample rate selection support, read the stream
parameters that might change when running at different sample rates.

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

1 files changed, 90 insertions, 2 deletions

diff --git a/sound/firewire/dice.c b/sound/firewire/dice.c
index 49b47ba09cdd..e6bba6d32bd8 100644
--- a/sound/firewire/dice.c
+++ b/sound/firewire/dice.c
@@ -6,10 +6,12 @@
  */
 
 #include <linux/compat.h>
+#include <linux/completion.h>
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/firewire.h>
 #include <linux/firewire-constants.h>
+#include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
 #include <linux/mutex.h>
@@ -37,11 +39,14 @@ struct dice {
         unsigned int global_offset;
         unsigned int rx_offset;
         unsigned int clock_caps;
+        unsigned int rx_channels[3];
+        unsigned int rx_midi_ports[3];
         struct fw_address_handler notification_handler;
         int owner_generation;
         int dev_lock_count; /* > 0 driver, < 0 userspace */
         bool dev_lock_changed;
         bool global_enabled;
+        struct completion clock_accepted;
         wait_queue_head_t hwdep_wait;
         u32 notification_bits;
         struct fw_iso_resources resources;
@@ -53,15 +58,23 @@ MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
 MODULE_LICENSE("GPL v2");
 
 static const unsigned int dice_rates[] = {
+        /* mode 0 */
         [0] =  32000,
         [1] =  44100,
         [2] =  48000,
+        /* mode 1 */
         [3] =  88200,
         [4] =  96000,
+        /* mode 2 */
         [5] = 176400,
         [6] = 192000,
 };
 
+static unsigned int rate_index_to_mode(unsigned int rate_index)
+{
+        return ((int)rate_index - 1) / 2;
+}
+
 static void dice_lock_changed(struct dice *dice)
 {
         dice->dev_lock_changed = true;
@@ -264,6 +277,7 @@ static void dice_notification(struct fw_card *card, struct fw_request *request,
                               void *data, size_t length, void *callback_data)
 {
         struct dice *dice = callback_data;
+        u32 bits;
         unsigned long flags;
 
         if (tcode != TCODE_WRITE_QUADLET_REQUEST) {
@@ -274,10 +288,17 @@ static void dice_notification(struct fw_card *card, struct fw_request *request,
                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
                 return;
         }
+
+        bits = be32_to_cpup(data);
+
         spin_lock_irqsave(&dice->lock, flags);
-        dice->notification_bits |= be32_to_cpup(data);
+        dice->notification_bits |= bits;
         spin_unlock_irqrestore(&dice->lock, flags);
+
         fw_send_response(card, request, RCODE_COMPLETE);
+
+        if (bits & NOTIFY_CLOCK_ACCEPTED)
+                complete(&dice->clock_accepted);
         wake_up(&dice->hwdep_wait);
 }
 
@@ -457,6 +478,26 @@ static void dice_stream_stop(struct dice *dice)
         fw_iso_resources_free(&dice->resources);
 }
 
+static int dice_change_rate(struct dice *dice, unsigned int clock_rate)
+{
+        __be32 value;
+        int err;
+
+        INIT_COMPLETION(dice->clock_accepted);
+
+        value = cpu_to_be32(clock_rate | CLOCK_SOURCE_ARX1);
+        err = snd_fw_transaction(dice->unit, TCODE_WRITE_QUADLET_REQUEST,
+                                 global_address(dice, GLOBAL_CLOCK_SELECT),
+                                 &value, 4, 0);
+        if (err < 0)
+                return err;
+
+        wait_for_completion_timeout(&dice->clock_accepted,
+                                    msecs_to_jiffies(100));
+
+        return 0;
+}
+
 static int dice_hw_params(struct snd_pcm_substream *substream,
                           struct snd_pcm_hw_params *hw_params)
 {
@@ -831,11 +872,51 @@ static int dice_interface_check(struct fw_unit *unit)
         return 0;
 }
 
+static int highest_supported_mode_rate(struct dice *dice, unsigned int mode)
+{
+        int i;
+
+        for (i = ARRAY_SIZE(dice_rates) - 1; i >= 0; --i)
+                if ((dice->clock_caps & (1 << i)) &&
+                    rate_index_to_mode(i) == mode)
+                        return i;
+
+        return -1;
+}
+
+static int dice_read_mode_params(struct dice *dice, unsigned int mode)
+{
+        __be32 values[2];
+        int rate_index, err;
+
+        rate_index = highest_supported_mode_rate(dice, mode);
+        if (rate_index < 0) {
+                dice->rx_channels[mode] = 0;
+                dice->rx_midi_ports[mode] = 0;
+                return 0;
+        }
+
+        err = dice_change_rate(dice, rate_index << CLOCK_RATE_SHIFT);
+        if (err < 0)
+                return err;
+
+        err = snd_fw_transaction(dice->unit, TCODE_READ_BLOCK_REQUEST,
+                                 rx_address(dice, RX_NUMBER_AUDIO),
+                                 values, 2 * 4, 0);
+        if (err < 0)
+                return err;
+
+        dice->rx_channels[mode]   = be32_to_cpu(values[0]);
+        dice->rx_midi_ports[mode] = be32_to_cpu(values[1]);
+
+        return 0;
+}
+
 static int dice_read_params(struct dice *dice)
 {
         __be32 pointers[6];
         __be32 value;
-        int err;
+        int mode, err;
 
         err = snd_fw_transaction(dice->unit, TCODE_READ_BLOCK_REQUEST,
                                  DICE_PRIVATE_SPACE,
@@ -863,6 +944,12 @@ static int dice_read_params(struct dice *dice)
                                    CLOCK_CAP_SOURCE_INTERNAL;
         }
 
+        for (mode = 2; mode >= 0; --mode) {
+                err = dice_read_mode_params(dice, mode);
+                if (err < 0)
+                        return err;
+        }
+
         return 0;
 }
 
@@ -922,6 +1009,7 @@ static int dice_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
         spin_lock_init(&dice->lock);
         mutex_init(&dice->mutex);
         dice->unit = unit;
+        init_completion(&dice->clock_accepted);
         init_waitqueue_head(&dice->hwdep_wait);
 
         dice->notification_handler.length = 4;