fw_iso_ctx_private: add inline function to compute timeStamp field in IR/IT descriptors

The layout of timeStamp field in descriptor of IT/IR context is defined in
1394 OHCI specification.

This commit adds inline functions to parse it.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>

5 files changed, 27 insertions, 12 deletions

diff --git a/src/fw_iso_ctx_private.h b/src/fw_iso_ctx_private.h
index cdbe897..45d3e2c 100644
--- a/src/fw_iso_ctx_private.h
+++ b/src/fw_iso_ctx_private.h
@@ -35,6 +35,21 @@ static inline guint ieee1394_iso_header_to_data_length(guint iso_header)
 		IEEE1394_ISO_HEADER_DATA_LENGTH_SHIFT;
 }
 
+#define OHCI1394_ISOC_DESC_timeStamp_SEC_MASK		0x0000e000
+#define OHCI1394_ISOC_DESC_timeStamp_SEC_SHIFT		13
+#define OHCI1394_ISOC_DESC_timeStmap_CYCLE_MASK		0x00001fff
+
+static inline guint ohci1394_isoc_desc_tstamp_to_sec(guint32 tstamp)
+{
+	return (tstamp & OHCI1394_ISOC_DESC_timeStamp_SEC_MASK) >>
+							OHCI1394_ISOC_DESC_timeStamp_SEC_SHIFT;
+}
+
+static inline guint ohci1394_isoc_desc_tstamp_to_cycle(guint32 tstamp)
+{
+	return (tstamp & OHCI1394_ISOC_DESC_timeStmap_CYCLE_MASK);
+}
+
 struct fw_iso_ctx_state {
 	int fd;
 	guint handle;
diff --git a/src/fw_iso_rx_single.c b/src/fw_iso_rx_single.c
index 0efbd4a..3ffb3a2 100644
--- a/src/fw_iso_rx_single.c
+++ b/src/fw_iso_rx_single.c
@@ -59,8 +59,8 @@ static void hinoko_fw_iso_rx_single_class_init(HinokoFwIsoRxSingleClass *klass)
 	/**
 	 * HinokoFwIsoRxSingle::interrupted:
 	 * @self: A [class@FwIsoRxSingle]
-	 * @sec: sec part of isochronous cycle when interrupt occurs.
-	 * @cycle: cycle part of of isochronous cycle when interrupt occurs.
+	 * @sec: sec part of isochronous cycle when interrupt occurs, up to 7.
+	 * @cycle: cycle part of of isochronous cycle when interrupt occurs, up to 7999.
 	 * @header: (array length=header_length) (element-type guint8): The headers of IR context
 	 *	    for handled packets.
 	 * @header_length: the number of bytes for @header.
@@ -183,8 +183,8 @@ gboolean fw_iso_rx_single_handle_event(HinokoFwIsoCtx *inst, const union fw_cdev
 	priv = hinoko_fw_iso_rx_single_get_instance_private(self);
 
 	ev = &event->iso_interrupt;
-	sec = (ev->cycle & 0x0000e000) >> 13;
-	cycle = ev->cycle & 0x00001fff;
+	sec = ohci1394_isoc_desc_tstamp_to_sec(ev->cycle);
+	cycle = ohci1394_isoc_desc_tstamp_to_cycle(ev->cycle);
 	count = ev->header_length / priv->header_size;
 
 	// TODO; handling error?
diff --git a/src/fw_iso_rx_single.h b/src/fw_iso_rx_single.h
index 87c2b03..a06b510 100644
--- a/src/fw_iso_rx_single.h
+++ b/src/fw_iso_rx_single.h
@@ -17,8 +17,8 @@ struct _HinokoFwIsoRxSingleClass {
 	/**
 	 * HinokoFwIsoRxSingleClass::interrupted:
 	 * @self: A [class@FwIsoRxSingle].
-	 * @sec: sec part of isochronous cycle when interrupt occurs.
-	 * @cycle: cycle part of of isochronous cycle when interrupt occurs.
+	 * @sec: The sec part of isochronous cycle when interrupt occurs, up to 7.
+	 * @cycle: The cycle part of of isochronous cycle when interrupt occurs, up to 7999.
 	 * @header: (array length=header_length) (element-type guint8): The headers of IR context
 	 *	    for handled packets.
 	 * @header_length: the number of bytes for header.
diff --git a/src/fw_iso_tx.c b/src/fw_iso_tx.c
index 698a620..aba8b31 100644
--- a/src/fw_iso_tx.c
+++ b/src/fw_iso_tx.c
@@ -53,8 +53,8 @@ static void hinoko_fw_iso_tx_class_init(HinokoFwIsoTxClass *klass)
 	/**
 	 * HinokoFwIsoTx::interrupted:
 	 * @self: A [class@FwIsoTx].
-	 * @sec: sec part of isochronous cycle when interrupt occurs.
-	 * @cycle: cycle part of of isochronous cycle when interrupt occurs.
+	 * @sec: sec part of isochronous cycle when interrupt occurs, up to 7.
+	 * @cycle: cycle part of of isochronous cycle when interrupt occurs, up to 7999.
 	 * @tstamp: (array length=tstamp_length) (element-type guint8): A series of timestamps for
 	 *	    packets already handled.
 	 * @tstamp_length: the number of bytes for @tstamp.
@@ -175,8 +175,8 @@ gboolean fw_iso_tx_handle_event(HinokoFwIsoCtx *inst, const union fw_cdev_event
 
 	ev = &event->iso_interrupt;
 
-	sec = (ev->cycle & 0x0000e000) >> 13;
-	cycle = ev->cycle & 0x00001fff;
+	sec = ohci1394_isoc_desc_tstamp_to_sec(ev->cycle);
+	cycle = ohci1394_isoc_desc_tstamp_to_cycle(ev->cycle);
 	pkt_count = ev->header_length / 4;
 
 	g_signal_emit(inst, fw_iso_tx_sigs[FW_ISO_TX_SIG_TYPE_IRQ], 0, sec, cycle, ev->header,
diff --git a/src/fw_iso_tx.h b/src/fw_iso_tx.h
index a888bed..ef3ec7f 100644
--- a/src/fw_iso_tx.h
+++ b/src/fw_iso_tx.h
@@ -16,8 +16,8 @@ struct _HinokoFwIsoTxClass {
 	/**
 	 * HinokoFwIsoTxClass::interrupted:
 	 * @self: A [class@FwIsoTx].
-	 * @sec: sec part of isochronous cycle when interrupt occurs.
-	 * @cycle: cycle part of of isochronous cycle when interrupt occurs.
+	 * @sec: The sec part of isochronous cycle when interrupt occurs, up to 7.
+	 * @cycle: The cycle part of of isochronous cycle when interrupt occurs, up to 7999.
 	 * @tstamp: (array length=tstamp_length) (element-type guint8): A series of timestamps for
 	 *	    packets already handled.
 	 * @tstamp_length: the number of bytes for @tstamp.