sr: Made the dev_config_set parameter a const pointer

[libsigrok.git] / hardware / alsa / alsa.c

diff --git a/hardware/alsa/alsa.c b/hardware/alsa/alsa.c
index d915f05830493a53ab9f7f9b56dcafd748b7b937..d86ac05fd39f619378b195ee991ad6ea956052eb 100644 (file)
--- a/hardware/alsa/alsa.c
+++ b/hardware/alsa/alsa.c
@@ -42,7 +42,7 @@ struct sr_analog_sample {
        struct sr_analog_probe probes[];
 };
 
-static int hwcaps[] = {
+static const int hwcaps[] = {
        SR_HWCAP_SAMPLERATE,
        SR_HWCAP_LIMIT_SAMPLES,
        SR_HWCAP_CONTINUOUS,
@@ -63,7 +63,7 @@ struct context {
        uint64_t limit_samples;
        snd_pcm_t *capture_handle;
        snd_pcm_hw_params_t *hw_params;
-       gpointer session_id;
+       void *session_dev_id;
 };
 
 static int hw_init(const char *devinfo)
@@ -99,31 +99,31 @@ static int hw_dev_open(int dev_index)
 {
        struct sr_dev_inst *sdi;
        struct context *ctx;
-       int err;
+       int ret;
 
        if (!(sdi = sr_dev_inst_get(dev_insts, dev_index)))
                return SR_ERR;
        ctx = sdi->priv;
 
-       err = snd_pcm_open(&ctx->capture_handle, AUDIO_DEV,
+       ret = snd_pcm_open(&ctx->capture_handle, AUDIO_DEV,
                           SND_PCM_STREAM_CAPTURE, 0);
-       if (err < 0) {
+       if (ret < 0) {
                sr_err("alsa: can't open audio device %s (%s)", AUDIO_DEV,
-                      snd_strerror(err));
+                      snd_strerror(ret));
                return SR_ERR;
        }
 
-       err = snd_pcm_hw_params_malloc(&ctx->hw_params);
-       if (err < 0) {
+       ret = snd_pcm_hw_params_malloc(&ctx->hw_params);
+       if (ret < 0) {
                sr_err("alsa: can't allocate hardware parameter structure (%s)",
-                      snd_strerror(err));
+                      snd_strerror(ret));
                return SR_ERR;
        }
 
-       err = snd_pcm_hw_params_any(ctx->capture_handle, ctx->hw_params);
-       if (err < 0) {
+       ret = snd_pcm_hw_params_any(ctx->capture_handle, ctx->hw_params);
+       if (ret < 0) {
                sr_err("alsa: can't initialize hardware parameter structure "
-                      "(%s)", snd_strerror(err));
+                      "(%s)", snd_strerror(ret));
                return SR_ERR;
        }
 
@@ -137,12 +137,12 @@ static int hw_dev_close(int dev_index)
 
        if (!(sdi = sr_dev_inst_get(dev_insts, dev_index))) {
                sr_err("alsa: %s: sdi was NULL", __func__);
-               return SR_ERR; /* TODO: SR_ERR_ARG? */
+               return SR_ERR_BUG;
        }
 
        if (!(ctx = sdi->priv)) {
                sr_err("alsa: %s: sdi->priv was NULL", __func__);
-               return SR_ERR; /* TODO: SR_ERR_ARG? */
+               return SR_ERR_BUG;
        }
 
        // TODO: Return values of snd_*?
@@ -168,7 +168,7 @@ static int hw_cleanup(void)
        return SR_OK;
 }
 
-static void *hw_dev_info_get(int dev_index, int dev_info_id)
+static const void *hw_dev_info_get(int dev_index, int dev_info_id)
 {
        struct sr_dev_inst *sdi;
        struct context *ctx;
@@ -207,12 +207,12 @@ static int hw_dev_status_get(int dev_index)
        return SR_ST_ACTIVE;
 }
 
-static int *hw_hwcap_get_all(void)
+static const int *hw_hwcap_get_all(void)
 {
        return hwcaps;
 }
 
-static int hw_dev_config_set(int dev_index, int hwcap, void *value)
+static int hw_dev_config_set(int dev_index, int hwcap, const void *value)
 {
        struct sr_dev_inst *sdi;
        struct context *ctx;
@@ -225,10 +225,10 @@ static int hw_dev_config_set(int dev_index, int hwcap, void *value)
        case SR_HWCAP_PROBECONFIG:
                return SR_OK;
        case SR_HWCAP_SAMPLERATE:
-               ctx->cur_rate = *(uint64_t *)value;
+               ctx->cur_rate = *(const uint64_t *)value;
                return SR_OK;
        case SR_HWCAP_LIMIT_SAMPLES:
-               ctx->limit_samples = *(uint64_t *)value;
+               ctx->limit_samples = *(const uint64_t *)value;
                return SR_OK;
        default:
                return SR_ERR;
@@ -293,7 +293,7 @@ static int receive_data(int fd, int revents, void *cb_data)
        return TRUE;
 }
 
-static int hw_dev_acquisition_start(int dev_index, void *session_dev_id)
+static int hw_dev_acquisition_start(int dev_index, void *cb_data)
 {
        struct sr_dev_inst *sdi;
        struct context *ctx;
@@ -301,51 +301,51 @@ static int hw_dev_acquisition_start(int dev_index, void *session_dev_id)
        struct sr_datafeed_header header;
        struct pollfd *ufds;
        int count;
-       int err;
+       int ret;
 
        if (!(sdi = sr_dev_inst_get(dev_insts, dev_index)))
                return SR_ERR;
        ctx = sdi->priv;
 
-       err = snd_pcm_hw_params_set_access(ctx->capture_handle,
+       ret = snd_pcm_hw_params_set_access(ctx->capture_handle,
                        ctx->hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
-       if (err < 0) {
-               sr_err("alsa: can't set access type (%s)", snd_strerror(err));
+       if (ret < 0) {
+               sr_err("alsa: can't set access type (%s)", snd_strerror(ret));
                return SR_ERR;
        }
 
        /* FIXME: Hardcoded for 16bits */
-       err = snd_pcm_hw_params_set_format(ctx->capture_handle,
+       ret = snd_pcm_hw_params_set_format(ctx->capture_handle,
                        ctx->hw_params, SND_PCM_FORMAT_S16_LE);
-       if (err < 0) {
-               sr_err("alsa: can't set sample format (%s)", snd_strerror(err));
+       if (ret < 0) {
+               sr_err("alsa: can't set sample format (%s)", snd_strerror(ret));
                return SR_ERR;
        }
 
-       err = snd_pcm_hw_params_set_rate_near(ctx->capture_handle,
+       ret = snd_pcm_hw_params_set_rate_near(ctx->capture_handle,
                        ctx->hw_params, (unsigned int *)&ctx->cur_rate, 0);
-       if (err < 0) {
-               sr_err("alsa: can't set sample rate (%s)", snd_strerror(err));
+       if (ret < 0) {
+               sr_err("alsa: can't set sample rate (%s)", snd_strerror(ret));
                return SR_ERR;
        }
 
-       err = snd_pcm_hw_params_set_channels(ctx->capture_handle,
+       ret = snd_pcm_hw_params_set_channels(ctx->capture_handle,
                        ctx->hw_params, NUM_PROBES);
-       if (err < 0) {
-               sr_err("alsa: can't set channel count (%s)", snd_strerror(err));
+       if (ret < 0) {
+               sr_err("alsa: can't set channel count (%s)", snd_strerror(ret));
                return SR_ERR;
        }
 
-       err = snd_pcm_hw_params(ctx->capture_handle, ctx->hw_params);
-       if (err < 0) {
-               sr_err("alsa: can't set parameters (%s)", snd_strerror(err));
+       ret = snd_pcm_hw_params(ctx->capture_handle, ctx->hw_params);
+       if (ret < 0) {
+               sr_err("alsa: can't set parameters (%s)", snd_strerror(ret));
                return SR_ERR;
        }
 
-       err = snd_pcm_prepare(ctx->capture_handle);
-       if (err < 0) {
+       ret = snd_pcm_prepare(ctx->capture_handle);
+       if (ret < 0) {
                sr_err("alsa: can't prepare audio interface for use (%s)",
-                      snd_strerror(err));
+                      snd_strerror(ret));
                return SR_ERR;
        }
 
@@ -360,15 +360,15 @@ static int hw_dev_acquisition_start(int dev_index, void *session_dev_id)
                return SR_ERR_MALLOC;
        }
 
-       err = snd_pcm_poll_descriptors(ctx->capture_handle, ufds, count);
-       if (err < 0) {
+       ret = snd_pcm_poll_descriptors(ctx->capture_handle, ufds, count);
+       if (ret < 0) {
                sr_err("alsa: Unable to obtain poll descriptors (%s)",
-                      snd_strerror(err));
+                      snd_strerror(ret));
                g_free(ufds);
                return SR_ERR;
        }
 
-       ctx->session_id = session_dev_id;
+       ctx->session_dev_id = cb_data;
        sr_source_add(ufds[0].fd, ufds[0].events, 10, receive_data, sdi);
 
        packet.type = SR_DF_HEADER;
@@ -380,17 +380,18 @@ static int hw_dev_acquisition_start(int dev_index, void *session_dev_id)
        header.num_analog_probes = NUM_PROBES;
        header.num_logic_probes = 0;
        header.protocol_id = SR_PROTO_RAW;
-       sr_session_send(session_dev_id, &packet);
+       sr_session_send(cb_data, &packet);
        g_free(ufds);
 
        return SR_OK;
 }
 
-static int hw_dev_acquisition_stop(int dev_index, void *session_dev_id)
+/* TODO: This stops acquisition on ALL devices, ignoring dev_index. */
+static int hw_dev_acquisition_stop(int dev_index, void *cb_data)
 {
        /* Avoid compiler warnings. */
-       dev_index = dev_index;
-       session_dev_id = session_dev_id;
+       (void)dev_index;
+       (void)cb_data;
 
        return SR_OK;
 }