[PATCH] ASoC: cs-amp-lib: Check for no firmware controls when writing calibration

[Richard Fitzgerald <rf@opensource.cirrus.com>]

From: Simon Trimmer <simont@opensource.cirrus.com>

When a wmfw file has not been loaded the firmware control descriptions
necessary to write a stored calibration are not present. In this case
print a more descriptive error message.

The message is logged at info level because it is not fatal, and does
not necessarily imply that anything is broken.

Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
 sound/soc/codecs/cs-amp-lib.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/sound/soc/codecs/cs-amp-lib.c b/sound/soc/codecs/cs-amp-lib.c
index 01ef4db5407d..287ac01a3873 100644
--- a/sound/soc/codecs/cs-amp-lib.c
+++ b/sound/soc/codecs/cs-amp-lib.c
@@ -56,6 +56,11 @@ static int _cs_amp_write_cal_coeffs(struct cs_dsp *dsp,
 	dev_dbg(dsp->dev, "Calibration: Ambient=%#x, Status=%#x, CalR=%d\n",
 		data->calAmbient, data->calStatus, data->calR);
 
+	if (list_empty(&dsp->ctl_list)) {
+		dev_info(dsp->dev, "Calibration disabled due to missing firmware controls\n");
+		return -ENOENT;
+	}
+
 	ret = cs_amp_write_cal_coeff(dsp, controls, controls->ambient, data->calAmbient);
 	if (ret)
 		return ret;
-- 
2.39.2