Add null backendjellyfish_9.99.4jellyfish/9.99.49.99.4

Changes:
- Add null radio implementation that acts as the fallthrough default
  when the hardware implementations are not detected.
- Tweaked the probing in the tef665x implementation to not return an
  error if the I2C node is not even present. This cleans up the logs
  on start up on most platforms. These changes include some minor
  whitespace consistency clean ups.
- Added the run-by-default widget permission now that the binding
  should always work. This will ease testing, and potentially decrease
  app start up time.

Bug-AGL: SPEC-3570

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: I3c2e60ce7272d248ab87e3b79d6a334e17fe5531

5 files changed, 311 insertions, 10 deletions

diff --git a/binding/CMakeLists.txt b/binding/CMakeLists.txt
index 712e165..560dcaf 100644
--- a/binding/CMakeLists.txt
+++ b/binding/CMakeLists.txt
@@ -27,6 +27,7 @@ PROJECT_TARGET_ADD(radio-binding)
 	set(radio_SOURCES
 		radio-binding.c
 		radio_impl_kingfisher.c
+		radio_impl_null.c
 		radio_impl_rtlsdr.c
 		radio_impl_tef665x.c)
 
diff --git a/binding/radio-binding.c b/binding/radio-binding.c
index 0ab5565..34eb53e 100644
--- a/binding/radio-binding.c
+++ b/binding/radio-binding.c
@@ -27,6 +27,7 @@
 #include <afb/afb-binding.h>
 
 #include "radio_impl.h"
+#include "radio_impl_null.h"
 #include "radio_impl_rtlsdr.h"
 #include "radio_impl_kingfisher.h"
 #include "radio_impl_tef665x.h"
@@ -581,6 +582,11 @@ static int init(afb_api_t api)
 		rc = radio_impl_ops->init();
 	}
 	if (rc != 0) {
+		radio_impl_ops = &null_impl_ops;
+		rc = radio_impl_ops->init();
+	}
+	if (rc != 0) {
+		// We don't expect the null implementation to fail init, but just in case...
 		AFB_API_ERROR(afbBindingV3root, "No radio device found, exiting");
 	}
 	if(rc == 0) {
@@ -590,8 +596,6 @@ static int init(afb_api_t api)
 		{
 			radio_impl_ops->set_rds_callback(rds_callback);
 		}
-			
-
 	} else {
 		return rc;
 	}
diff --git a/binding/radio_impl_null.c b/binding/radio_impl_null.c
new file mode 100644
index 0000000..8c28bca
--- /dev/null
+++ b/binding/radio_impl_null.c
@@ -0,0 +1,267 @@
+/*
+ * Copyright (C) 2017,2018,2020 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * NOTE: Some locking around frequency and scanning state may be
+ *       required if this null implementation ever needs to be used
+ *       beyond basic functionality testing.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <string.h>
+#include <unistd.h>
+#include <pthread.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <glib.h>
+#include <afb/afb-binding.h>
+
+#include "radio_impl.h"
+
+// Structure to describe FM band plans, all values in Hz.
+typedef struct {
+	char *name;
+	uint32_t min;
+	uint32_t max;
+	uint32_t step;
+} fm_band_plan_t;
+
+static fm_band_plan_t known_fm_band_plans[5] = {
+	{ .name = "US", .min = 87900000, .max = 107900000, .step = 200000 },
+	{ .name = "JP", .min = 76000000, .max = 95000000, .step = 100000 },
+	{ .name = "EU", .min = 87500000, .max = 108000000, .step = 50000 },
+	{ .name = "ITU-1", .min = 87500000, .max = 108000000, .step = 50000 },
+	{ .name = "ITU-2", .min = 87900000, .max = 107900000, .step = 50000 }
+};
+
+static unsigned int bandplan;
+static bool present;
+static bool active;
+static bool scanning;
+static uint32_t current_frequency;
+static radio_freq_callback_t freq_callback;
+static void *freq_callback_data;
+
+static uint32_t null_get_min_frequency(radio_band_t band);
+static void null_set_frequency(uint32_t frequency);
+//static void null_scan_stop(void);
+
+static int null_init(void)
+{
+	GKeyFile *conf_file;
+	char *value_str;
+	char *rootdir;
+	char *helper_path;
+
+	if(present)
+		return 0;
+
+	// Load settings from configuration file if it exists
+	conf_file = g_key_file_new();
+	if(conf_file &&
+	   g_key_file_load_from_dirs(conf_file,
+				     "AGL.conf",
+				     (const gchar**) g_get_system_config_dirs(),
+				     NULL,
+				     G_KEY_FILE_KEEP_COMMENTS,
+				     NULL) == TRUE) {
+
+		// Set band plan if it is specified
+		value_str = g_key_file_get_string(conf_file,
+						  "radio",
+						  "fmbandplan",
+						  NULL);
+		if(value_str) {
+			unsigned int i;
+			for(i = 0;
+			    i < sizeof(known_fm_band_plans) / sizeof(fm_band_plan_t);
+			    i++) {
+				if(!strcasecmp(value_str, known_fm_band_plans[i].name)) {
+					bandplan = i;
+					break;
+				}
+			}
+		}
+	}
+
+	// Start off with minimum bandplan frequency
+	current_frequency = null_get_min_frequency(BAND_FM);
+
+	present = true;
+	null_set_frequency(current_frequency);
+
+	return 0;
+}
+
+static void null_set_output(const char *output)
+{
+}
+
+static uint32_t null_get_frequency(void)
+{
+	return current_frequency;
+}
+
+static void null_set_frequency(uint32_t frequency)
+{
+	current_frequency = frequency;
+
+	if(freq_callback)
+		freq_callback(current_frequency, freq_callback_data);
+}
+
+static void null_set_frequency_callback(radio_freq_callback_t callback,
+					void *data)
+{
+	freq_callback = callback;
+	freq_callback_data = data;
+}
+
+static radio_band_t null_get_band(void)
+{
+	// We only support FM
+	return BAND_FM;
+}
+
+static void null_set_band(radio_band_t band)
+{
+	// We only support FM, so do nothing
+}
+
+static int null_band_supported(radio_band_t band)
+{
+	if(band == BAND_FM)
+		return 1;
+	return 0;
+}
+
+static uint32_t null_get_min_frequency(radio_band_t band)
+{
+	return known_fm_band_plans[bandplan].min;
+}
+
+static uint32_t null_get_max_frequency(radio_band_t band)
+{
+	return known_fm_band_plans[bandplan].max;
+}
+
+static uint32_t null_get_frequency_step(radio_band_t band)
+{
+	uint32_t ret = 0;
+
+	switch (band) {
+	case BAND_AM:
+		ret = 1000; // 1 kHz
+		break;
+	case BAND_FM:
+		ret = known_fm_band_plans[bandplan].step;
+		break;
+	default:
+		break;
+	}
+	return ret;
+}
+
+static void null_start(void)
+{
+	if(!present)
+		return;
+
+	if(active)
+		return;
+
+	active = true;
+}
+
+static void null_stop(void)
+{
+	if(!present)
+		return;
+
+	if (!active)
+		return;
+
+	active = false;
+}
+
+static void null_scan_start(radio_scan_direction_t direction,
+			    radio_scan_callback_t callback,
+			    void *data)
+{
+	int frequency;
+
+	if(!active || scanning)
+		return;
+
+	scanning = true;
+
+	// Just go to the next frequency step up or down
+	frequency = current_frequency;
+	if(direction == SCAN_FORWARD) {
+		frequency += known_fm_band_plans[bandplan].step;
+	} else {
+		frequency -= known_fm_band_plans[bandplan].step;
+	}
+	if(frequency < known_fm_band_plans[bandplan].min)
+		frequency = known_fm_band_plans[bandplan].max;
+	else if(frequency > known_fm_band_plans[bandplan].max)
+		frequency = known_fm_band_plans[bandplan].min;
+
+	scanning = false;
+	null_set_frequency(frequency);
+	if(callback)
+		callback(frequency, data);
+}
+
+static void null_scan_stop(void)
+{
+	scanning = false;
+}
+
+static radio_stereo_mode_t null_get_stereo_mode(void)
+{
+	// We only support stereo
+	return STEREO;
+}
+
+static void null_set_stereo_mode(radio_stereo_mode_t mode)
+{
+	// We only support stereo, so do nothing
+}
+
+radio_impl_ops_t null_impl_ops = {
+	.name = "null/mock radio",
+	.init = null_init,
+	.set_output = null_set_output,
+	.get_frequency = null_get_frequency,
+	.set_frequency = null_set_frequency,
+	.set_frequency_callback = null_set_frequency_callback,
+	.get_band = null_get_band,
+	.set_band = null_set_band,
+	.band_supported = null_band_supported,
+	.get_min_frequency = null_get_min_frequency,
+	.get_max_frequency = null_get_max_frequency,
+	.get_frequency_step = null_get_frequency_step,
+	.start = null_start,
+	.stop = null_stop,
+	.scan_start = null_scan_start,
+	.scan_stop = null_scan_stop,
+	.get_stereo_mode = null_get_stereo_mode,
+	.set_stereo_mode = null_set_stereo_mode
+};
diff --git a/binding/radio_impl_null.h b/binding/radio_impl_null.h
new file mode 100644
index 0000000..16bd5e6
--- /dev/null
+++ b/binding/radio_impl_null.h
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2020 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _RADIO_IMPL_NULL_H
+#define _RADIO_IMPL_NULL_H
+
+#include "radio_impl.h"
+
+extern radio_impl_ops_t null_impl_ops;
+
+#endif /* _RADIO_IMPL_NULL_H */
+
diff --git a/binding/radio_impl_tef665x.c b/binding/radio_impl_tef665x.c
index eeac170..17454b8 100644
--- a/binding/radio_impl_tef665x.c
+++ b/binding/radio_impl_tef665x.c
@@ -2144,15 +2144,19 @@ static int tef665x_init()
 {
 	char gst_pipeline_str[GST_PIPELINE_LEN];
 	int rc;
-	int ret = i2c_init(I2C_DEV, _open, &file_desc);
 
 	current_am_frequency = known_am_band_plans[am_bandplan].min;
 	current_fm_frequency = known_fm_band_plans[fm_bandplan].min;
 
+	rc = i2c_init(I2C_DEV, _open, &file_desc);
+	if(rc < 0) {
+		AFB_NOTICE("tef665x not present");
+		return -1;
+	}
 	_debug("file_desc= ", file_desc);
 
-	ret = appl_get_identification(file_desc);
-	if(ret != 1){
+	rc = appl_get_identification(file_desc);
+	if(rc != 1){
 		AFB_ERROR("no tef665x!");
 		return -1;
 	}
@@ -2187,11 +2191,11 @@ static int tef665x_init()
 	}
 
 	// Start pipeline in paused state
-	ret = gst_element_set_state(pipeline, GST_STATE_PAUSED);
-	_debug("gst_element_set_state to pause (at the begining)", ret);
+	rc = gst_element_set_state(pipeline, GST_STATE_PAUSED);
+	_debug("gst_element_set_state to pause (at the begining)", rc);
 
-	ret = gst_bus_add_watch(gst_element_get_bus(pipeline), (GstBusFunc) handle_message, NULL);
-	_debug("gst_bus_add_watch   ret", ret);
+	rc = gst_bus_add_watch(gst_element_get_bus(pipeline), (GstBusFunc) handle_message, NULL);
+	_debug("gst_bus_add_watch   rc", rc);
 
 	present = true;
 
@@ -2200,7 +2204,7 @@ static int tef665x_init()
 	pthread_mutex_init (&RDS_Mutex, NULL);
 
 	tef665x_start();
-    return 0;
+	return 0;
 }
 
 static void tef665x_set_frequency_callback(radio_freq_callback_t callback,