From 82af1df465181da783d85256afdda26942eaecbf Mon Sep 17 00:00:00 2001
From: Jaroslav Kysela <perex@perex.cz>
Date: Fri, 11 Apr 2008 14:11:04 +0200
Subject: [PATCH] added snd_pcm_hw_params_is_monotonic/can_forward/can_rewind
 functions

---
 include/pcm.h       |  3 +++
 src/pcm/pcm.c       | 63 +++++++++++++++++++++++++++++++++++++++++++++
 src/pcm/pcm_hw.c    |  7 +++++
 src/pcm/pcm_local.h |  4 +++
 4 files changed, 77 insertions(+)

diff --git a/include/pcm.h b/include/pcm.h
index 4c2d456b..9a592e3d 100644
--- a/include/pcm.h
+++ b/include/pcm.h
@@ -518,7 +518,10 @@ int snd_pcm_hw_params_can_mmap_sample_resolution(const snd_pcm_hw_params_t *para
 int snd_pcm_hw_params_is_double(const snd_pcm_hw_params_t *params);
 int snd_pcm_hw_params_is_batch(const snd_pcm_hw_params_t *params);
 int snd_pcm_hw_params_is_block_transfer(const snd_pcm_hw_params_t *params);
+int snd_pcm_hw_params_is_monotonic(const snd_pcm_hw_params_t *params);
 int snd_pcm_hw_params_can_overrange(const snd_pcm_hw_params_t *params);
+int snd_pcm_hw_params_can_forward(const snd_pcm_hw_params_t *params);
+int snd_pcm_hw_params_can_rewind(const snd_pcm_hw_params_t *params);
 int snd_pcm_hw_params_can_pause(const snd_pcm_hw_params_t *params);
 int snd_pcm_hw_params_can_resume(const snd_pcm_hw_params_t *params);
 int snd_pcm_hw_params_is_half_duplex(const snd_pcm_hw_params_t *params);
diff --git a/src/pcm/pcm.c b/src/pcm/pcm.c
index a30d319a..e0f808c3 100644
--- a/src/pcm/pcm.c
+++ b/src/pcm/pcm.c
@@ -2811,6 +2811,27 @@ int snd_pcm_hw_params_is_block_transfer(const snd_pcm_hw_params_t *params)
 	return !!(params->info & SNDRV_PCM_INFO_BLOCK_TRANSFER);
 }
 
+/**
+ * \brief Check, if timestamps are monotonic for given configuration
+ * \param params Configuration space
+ * \return Boolean value
+ * \retval 0 Device doesn't do monotomic timestamps
+ * \retval 1 Device does monotonic timestamps
+ *
+ * It is not allowed to call this function when given configuration is not exactly one.
+ * Usually, #snd_pcm_hw_params() function chooses one configuration
+ * from the configuration space.
+ */
+int snd_pcm_hw_params_is_monotonic(const snd_pcm_hw_params_t *params)
+{
+	assert(params);
+	if (CHECK_SANITY(params->info == ~0U)) {
+		SNDMSG("invalid PCM info field");
+		return 0; /* FIXME: should be a negative error? */
+	}
+	return !!(params->info & SND_PCM_INFO_MONOTONIC);
+}
+
 /**
  * \brief Check, if hardware supports overrange detection
  * \param params Configuration space
@@ -2832,6 +2853,48 @@ int snd_pcm_hw_params_can_overrange(const snd_pcm_hw_params_t *params)
 	return !!(params->info & SNDRV_PCM_INFO_OVERRANGE);
 }
 
+/**
+ * \brief Check, if device supports forward
+ * \param params Configuration space
+ * \return Boolean value
+ * \retval 0 Device doesn't support forward
+ * \retval 1 Device supports forward
+ *
+ * It is not allowed to call this function when given configuration is not exactly one.
+ * Usually, #snd_pcm_hw_params() function chooses one configuration
+ * from the configuration space.
+ */
+int snd_pcm_hw_params_can_forward(const snd_pcm_hw_params_t *params)
+{
+	assert(params);
+	if (CHECK_SANITY(params->info == ~0U)) {
+		SNDMSG("invalid PCM info field");
+		return 0; /* FIXME: should be a negative error? */
+	}
+	return !!(params->info & SND_PCM_INFO_FORWARD);
+}
+
+/**
+ * \brief Check, if device supports rewind
+ * \param params Configuration space
+ * \return Boolean value
+ * \retval 0 Device doesn't support rewind
+ * \retval 1 Device supports rewind
+ *
+ * It is not allowed to call this function when given configuration is not exactly one.
+ * Usually, #snd_pcm_hw_params() function chooses one configuration
+ * from the configuration space.
+ */
+int snd_pcm_hw_params_can_rewind(const snd_pcm_hw_params_t *params)
+{
+	assert(params);
+	if (CHECK_SANITY(params->info == ~0U)) {
+		SNDMSG("invalid PCM info field");
+		return 0; /* FIXME: should be a negative error? */
+	}
+	return !!(params->info & SND_PCM_INFO_REWIND);
+}
+
 /**
  * \brief Check, if hardware supports pause
  * \param params Configuration space
diff --git a/src/pcm/pcm_hw.c b/src/pcm/pcm_hw.c
index 88b5e048..ebead2ff 100644
--- a/src/pcm/pcm_hw.c
+++ b/src/pcm/pcm_hw.c
@@ -245,6 +245,13 @@ static int snd_pcm_hw_hw_refine(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
 		// SYSMSG("SNDRV_PCM_IOCTL_HW_REFINE failed");
 		return err;
 	}
+
+	if (params->info != ~0UL) {
+		params->info &= ~0xf0000000;
+		params->info |= (pcm->monotonic ? SND_PCM_INFO_MONOTONIC : 0) |
+				 SND_PCM_INFO_REWIND |
+				 SND_PCM_INFO_FORWARD;
+	}
 	
 	return 0;
 }
diff --git a/src/pcm/pcm_local.h b/src/pcm/pcm_local.h
index 661d40ee..f0dae7cb 100644
--- a/src/pcm/pcm_local.h
+++ b/src/pcm/pcm_local.h
@@ -95,6 +95,10 @@ typedef enum sndrv_pcm_hw_param snd_pcm_hw_param_t;
 #define SND_PCM_HW_PARAMS_NORESAMPLE SNDRV_PCM_HW_PARAMS_NORESAMPLE
 #define SND_PCM_HW_PARAMS_EXPORT_BUFFER SNDRV_PCM_HW_PARAMS_EXPORT_BUFFER
 
+#define SND_PCM_INFO_FORWARD	0x10000000
+#define SND_PCM_INFO_REWIND	0x20000000
+#define SND_PCM_INFO_MONOTONIC	0x80000000
+
 typedef struct _snd_pcm_rbptr {
 	snd_pcm_t *master;
 	volatile snd_pcm_uframes_t *ptr;
-- 
2.47.1