diff options
author | Jerome Brunet <jbrunet@baylibre.com> | 2019-07-03 14:07:49 +0200 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2019-07-03 13:21:34 +0100 |
commit | 751bd5db52604f3f71d54dbad82707ef2475b707 (patch) | |
tree | 914c34f5ae36605e4fae0215c0c1a675e3a6c5ae | |
parent | 094380ea2bf9f0fa7d63e67bf500b8c77e8d1910 (diff) |
ASoC: meson: axg-tdm-formatter: add reset
Add the optional reset line handling which is present on the new SoC
families, such as the g12a. Triggering this reset is not critical but
it helps solve a channel shift issue on the g12a.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20190703120749.32341-3-jbrunet@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
-rw-r--r-- | sound/soc/meson/axg-tdm-formatter.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/sound/soc/meson/axg-tdm-formatter.c b/sound/soc/meson/axg-tdm-formatter.c index 0c6cce5c5773..2e498201139f 100644 --- a/sound/soc/meson/axg-tdm-formatter.c +++ b/sound/soc/meson/axg-tdm-formatter.c @@ -7,6 +7,7 @@ #include <linux/module.h> #include <linux/of_platform.h> #include <linux/regmap.h> +#include <linux/reset.h> #include <sound/soc.h> #include "axg-tdm-formatter.h" @@ -20,6 +21,7 @@ struct axg_tdm_formatter { struct clk *lrclk; struct clk *sclk_sel; struct clk *lrclk_sel; + struct reset_control *reset; bool enabled; struct regmap *map; }; @@ -76,6 +78,24 @@ static int axg_tdm_formatter_enable(struct axg_tdm_formatter *formatter) return 0; /* + * On the g12a (and possibly other SoCs), when a stream using + * multiple lanes is restarted, it will sometimes not start + * from the first lane, but randomly from another used one. + * The result is an unexpected and random channel shift. + * + * The hypothesis is that an HW counter is not properly reset + * and the formatter simply starts on the lane it stopped + * before. Unfortunately, there does not seems to be a way to + * reset this through the registers of the block. + * + * However, the g12a has indenpendent reset lines for each audio + * devices. Using this reset before each start solves the issue. + */ + ret = reset_control_reset(formatter->reset); + if (ret) + return ret; + + /* * If sclk is inverted, invert it back and provide the inversion * required by the formatter */ @@ -306,6 +326,15 @@ int axg_tdm_formatter_probe(struct platform_device *pdev) return ret; } + /* Formatter dedicated reset line */ + formatter->reset = reset_control_get_optional_exclusive(dev, NULL); + if (IS_ERR(formatter->reset)) { + ret = PTR_ERR(formatter->reset); + if (ret != -EPROBE_DEFER) + dev_err(dev, "failed to get reset: %d\n", ret); + return ret; + } + return devm_snd_soc_register_component(dev, drv->component_drv, NULL, 0); } |