baylibre-acme: Set update_interval when modifing samplerate.

[libsigrok.git] / src / hardware / baylibre-acme / protocol.c

diff --git a/src/hardware/baylibre-acme/protocol.c b/src/hardware/baylibre-acme/protocol.c
index ca09eba069c51a0c017f851b53b31d5779346d58..d0552553feffbebdb298cba9c1c848e0d87de1e8 100644 (file)
--- a/src/hardware/baylibre-acme/protocol.c
+++ b/src/hardware/baylibre-acme/protocol.c
@@ -295,6 +295,43 @@ static int get_shunt_path(const struct sr_channel_group *cg, GString *path)
        return ret;
 }
 
+/*
+ * Try setting the update_interval sysfs attribute for each probe according
+ * to samplerate.
+ */
+SR_PRIV void bl_acme_maybe_set_update_interval(const struct sr_dev_inst *sdi,
+                                              uint64_t samplerate)
+{
+       struct sr_channel_group *cg;
+       struct channel_group_priv *cgp;
+       GString *hwmon;
+       GSList *l;
+       FILE *fd;
+
+       for (l = sdi->channel_groups; l != NULL; l = l->next) {
+               cg = l->data;
+               cgp = cg->priv;
+
+               hwmon = g_string_sized_new(64);
+               g_string_append_printf(hwmon,
+                               "/sys/class/hwmon/hwmon%d/update_interval",
+                               cgp->hwmon_num);
+
+               if (g_file_test(hwmon->str, G_FILE_TEST_EXISTS)) {
+                       fd = g_fopen(hwmon->str, "w");
+                       if (!fd) {
+                               g_string_free(hwmon, TRUE);
+                               continue;
+                       }
+
+                       g_fprintf(fd, "%" PRIu64 "\n", 1000 / samplerate);
+                       fclose(fd);
+               }
+
+               g_string_free(hwmon, TRUE);
+       }
+}
+
 SR_PRIV int bl_acme_get_shunt(const struct sr_channel_group *cg,
                              uint64_t *shunt)
 {