ASoC: dapm: harden use of lookup tables

To detect potential errors, let's add:

a) build-time warnings when the table size isn't aligned with the enum
list
b) run-time warnings when the values are not initialized. This
requires an increase by one of all values to avoid the default 0.
Suggested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

include/sound/soc-dapm.h

@@ -523,6 +523,9 @@ enum snd_soc_dapm_type {
 	snd_soc_dapm_asrc,		/* DSP/CODEC ASRC component */
 	snd_soc_dapm_encoder,		/* FW/SW audio encoder component */
 	snd_soc_dapm_decoder,		/* FW/SW audio decoder component */
+
+	/* Don't edit below this line */
+	SND_SOC_DAPM_TYPE_COUNT
 };
 
 enum snd_soc_dapm_subclass {

sound/soc/soc-dapm.c

@@ -64,85 +64,85 @@ snd_soc_dapm_new_control_unlocked(struct snd_soc_dapm_context *dapm,
 
 /* dapm power sequences - make this per codec in the future */
 static int dapm_up_seq[] = {
-	[snd_soc_dapm_pre] = 0,
-	[snd_soc_dapm_regulator_supply] = 1,
-	[snd_soc_dapm_pinctrl] = 1,
-	[snd_soc_dapm_clock_supply] = 1,
-	[snd_soc_dapm_supply] = 2,
-	[snd_soc_dapm_micbias] = 3,
-	[snd_soc_dapm_vmid] = 3,
-	[snd_soc_dapm_dai_link] = 2,
-	[snd_soc_dapm_dai_in] = 4,
-	[snd_soc_dapm_dai_out] = 4,
-	[snd_soc_dapm_aif_in] = 4,
-	[snd_soc_dapm_aif_out] = 4,
-	[snd_soc_dapm_mic] = 5,
-	[snd_soc_dapm_siggen] = 5,
-	[snd_soc_dapm_input] = 5,
-	[snd_soc_dapm_output] = 5,
-	[snd_soc_dapm_mux] = 6,
-	[snd_soc_dapm_demux] = 6,
-	[snd_soc_dapm_dac] = 7,
-	[snd_soc_dapm_switch] = 8,
-	[snd_soc_dapm_mixer] = 8,
-	[snd_soc_dapm_mixer_named_ctl] = 8,
-	[snd_soc_dapm_pga] = 9,
-	[snd_soc_dapm_buffer] = 9,
-	[snd_soc_dapm_scheduler] = 9,
-	[snd_soc_dapm_effect] = 9,
-	[snd_soc_dapm_src] = 9,
-	[snd_soc_dapm_asrc] = 9,
-	[snd_soc_dapm_encoder] = 9,
-	[snd_soc_dapm_decoder] = 9,
-	[snd_soc_dapm_adc] = 10,
-	[snd_soc_dapm_out_drv] = 11,
-	[snd_soc_dapm_hp] = 11,
-	[snd_soc_dapm_spk] = 11,
-	[snd_soc_dapm_line] = 11,
-	[snd_soc_dapm_sink] = 11,
-	[snd_soc_dapm_kcontrol] = 12,
-	[snd_soc_dapm_post] = 13,
+	[snd_soc_dapm_pre] = 1,
+	[snd_soc_dapm_regulator_supply] = 2,
+	[snd_soc_dapm_pinctrl] = 2,
+	[snd_soc_dapm_clock_supply] = 2,
+	[snd_soc_dapm_supply] = 3,
+	[snd_soc_dapm_micbias] = 4,
+	[snd_soc_dapm_vmid] = 4,
+	[snd_soc_dapm_dai_link] = 3,
+	[snd_soc_dapm_dai_in] = 5,
+	[snd_soc_dapm_dai_out] = 5,
+	[snd_soc_dapm_aif_in] = 5,
+	[snd_soc_dapm_aif_out] = 5,
+	[snd_soc_dapm_mic] = 6,
+	[snd_soc_dapm_siggen] = 6,
+	[snd_soc_dapm_input] = 6,
+	[snd_soc_dapm_output] = 6,
+	[snd_soc_dapm_mux] = 7,
+	[snd_soc_dapm_demux] = 7,
+	[snd_soc_dapm_dac] = 8,
+	[snd_soc_dapm_switch] = 9,
+	[snd_soc_dapm_mixer] = 9,
+	[snd_soc_dapm_mixer_named_ctl] = 9,
+	[snd_soc_dapm_pga] = 10,
+	[snd_soc_dapm_buffer] = 10,
+	[snd_soc_dapm_scheduler] = 10,
+	[snd_soc_dapm_effect] = 10,
+	[snd_soc_dapm_src] = 10,
+	[snd_soc_dapm_asrc] = 10,
+	[snd_soc_dapm_encoder] = 10,
+	[snd_soc_dapm_decoder] = 10,
+	[snd_soc_dapm_adc] = 11,
+	[snd_soc_dapm_out_drv] = 12,
+	[snd_soc_dapm_hp] = 12,
+	[snd_soc_dapm_spk] = 12,
+	[snd_soc_dapm_line] = 12,
+	[snd_soc_dapm_sink] = 12,
+	[snd_soc_dapm_kcontrol] = 13,
+	[snd_soc_dapm_post] = 14,
 };
 
 static int dapm_down_seq[] = {
-	[snd_soc_dapm_pre] = 0,
-	[snd_soc_dapm_kcontrol] = 1,
-	[snd_soc_dapm_adc] = 2,
-	[snd_soc_dapm_hp] = 3,
-	[snd_soc_dapm_spk] = 3,
-	[snd_soc_dapm_line] = 3,
-	[snd_soc_dapm_out_drv] = 3,
-	[snd_soc_dapm_sink] = 3,
-	[snd_soc_dapm_pga] = 4,
-	[snd_soc_dapm_buffer] = 4,
-	[snd_soc_dapm_scheduler] = 4,
-	[snd_soc_dapm_effect] = 4,
-	[snd_soc_dapm_src] = 4,
-	[snd_soc_dapm_asrc] = 4,
-	[snd_soc_dapm_encoder] = 4,
-	[snd_soc_dapm_decoder] = 4,
-	[snd_soc_dapm_switch] = 5,
-	[snd_soc_dapm_mixer_named_ctl] = 5,
-	[snd_soc_dapm_mixer] = 5,
-	[snd_soc_dapm_dac] = 6,
-	[snd_soc_dapm_mic] = 7,
-	[snd_soc_dapm_siggen] = 7,
-	[snd_soc_dapm_input] = 7,
-	[snd_soc_dapm_output] = 7,
-	[snd_soc_dapm_micbias] = 8,
-	[snd_soc_dapm_vmid] = 8,
-	[snd_soc_dapm_mux] = 9,
-	[snd_soc_dapm_demux] = 9,
-	[snd_soc_dapm_aif_in] = 10,
-	[snd_soc_dapm_aif_out] = 10,
-	[snd_soc_dapm_dai_in] = 10,
-	[snd_soc_dapm_dai_out] = 10,
-	[snd_soc_dapm_dai_link] = 11,
-	[snd_soc_dapm_supply] = 12,
-	[snd_soc_dapm_clock_supply] = 13,
-	[snd_soc_dapm_pinctrl] = 13,
-	[snd_soc_dapm_regulator_supply] = 13,
-	[snd_soc_dapm_post] = 14,
+	[snd_soc_dapm_pre] = 1,
+	[snd_soc_dapm_kcontrol] = 2,
+	[snd_soc_dapm_adc] = 3,
+	[snd_soc_dapm_hp] = 4,
+	[snd_soc_dapm_spk] = 4,
+	[snd_soc_dapm_line] = 4,
+	[snd_soc_dapm_out_drv] = 4,
+	[snd_soc_dapm_sink] = 4,
+	[snd_soc_dapm_pga] = 5,
+	[snd_soc_dapm_buffer] = 5,
+	[snd_soc_dapm_scheduler] = 5,
+	[snd_soc_dapm_effect] = 5,
+	[snd_soc_dapm_src] = 5,
+	[snd_soc_dapm_asrc] = 5,
+	[snd_soc_dapm_encoder] = 5,
+	[snd_soc_dapm_decoder] = 5,
+	[snd_soc_dapm_switch] = 6,
+	[snd_soc_dapm_mixer_named_ctl] = 6,
+	[snd_soc_dapm_mixer] = 6,
+	[snd_soc_dapm_dac] = 7,
+	[snd_soc_dapm_mic] = 8,
+	[snd_soc_dapm_siggen] = 8,
+	[snd_soc_dapm_input] = 8,
+	[snd_soc_dapm_output] = 8,
+	[snd_soc_dapm_micbias] = 9,
+	[snd_soc_dapm_vmid] = 9,
+	[snd_soc_dapm_mux] = 10,
+	[snd_soc_dapm_demux] = 10,
+	[snd_soc_dapm_aif_in] = 11,
+	[snd_soc_dapm_aif_out] = 11,
+	[snd_soc_dapm_dai_in] = 11,
+	[snd_soc_dapm_dai_out] = 11,
+	[snd_soc_dapm_dai_link] = 12,
+	[snd_soc_dapm_supply] = 13,
+	[snd_soc_dapm_clock_supply] = 14,
+	[snd_soc_dapm_pinctrl] = 14,
+	[snd_soc_dapm_regulator_supply] = 14,
+	[snd_soc_dapm_post] = 15,
 };
 
 static void dapm_assert_locked(struct snd_soc_dapm_context *dapm)
@@ -1425,11 +1425,17 @@ static int dapm_seq_compare(struct snd_soc_dapm_widget *a,
 {
 	int *sort;
 
+	BUILD_BUG_ON(ARRAY_SIZE(dapm_up_seq) != SND_SOC_DAPM_TYPE_COUNT);
+	BUILD_BUG_ON(ARRAY_SIZE(dapm_down_seq) != SND_SOC_DAPM_TYPE_COUNT);
+
 	if (power_up)
 		sort = dapm_up_seq;
 	else
 		sort = dapm_down_seq;
 
+	WARN_ONCE(sort[a->id] == 0, "offset a->id %d not initialized\n", a->id);
+	WARN_ONCE(sort[b->id] == 0, "offset b->id %d not initialized\n", b->id);
+
 	if (sort[a->id] != sort[b->id])
 		return sort[a->id] - sort[b->id];
 	if (a->subseq != b->subseq) {