The sii902x driver has existing suspend/resume handlers that save and
restore video-related register context (TPI mode and interrupts), but
these handlers were not saving/restoring audio configuration registers.
This caused HDMI audio to stop working after system suspend/resume cycles.
Therefore add audio-related register context to the existing
suspend/resume handlers when audio context needs to be saved/restored. As
well as mclk for the sake of power saving, in the case of sii902x being
the frame producer.
The audio context is only saved/restored when audio.active is true,
avoiding unnecessary register access when audio is not in use.
Tested on TI SK-AM62P-LP board with HDMI audio playback across multiple
suspend/resume cycles.
Signed-off-by: Sen Wang <[email protected]>
---
drivers/gpu/drm/bridge/sii902x.c | 91 +++++++++++++++++++++++++++++++-
1 file changed, 90 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index 134657041799..fd38a6ae86b2 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -192,6 +192,13 @@ struct sii902x {
struct platform_device *pdev;
struct clk *mclk;
u32 i2s_fifo_sequence[4];
+ bool active;
+ /* Audio register context for save/resume */
+ unsigned int ctx_i2s_input_config;
+ unsigned int ctx_audio_config_byte2;
+ unsigned int ctx_audio_config_byte3;
+ u8 ctx_i2s_stream_header[SII902X_TPI_I2S_STRM_HDR_SIZE];
+ u8 ctx_audio_infoframe[SII902X_TPI_MISC_INFOFRAME_SIZE];
} audio;
};
@@ -764,6 +771,8 @@ static int sii902x_audio_hw_params(struct device *dev, void *data,
if (ret)
goto out;
+ sii902x->audio.active = true;
+
dev_dbg(dev, "%s: hdmi audio enabled\n", __func__);
out:
mutex_unlock(&sii902x->mutex);
@@ -786,6 +795,8 @@ static void sii902x_audio_shutdown(struct device *dev, void
*data)
regmap_write(sii902x->regmap, SII902X_TPI_AUDIO_CONFIG_BYTE2_REG,
SII902X_TPI_AUDIO_INTERFACE_DISABLE);
+ sii902x->audio.active = false;
+
mutex_unlock(&sii902x->mutex);
clk_disable_unprepare(sii902x->audio.mclk);
@@ -1081,7 +1092,7 @@ static int __maybe_unused sii902x_resume(struct device
*dev)
{
struct sii902x *sii902x = dev_get_drvdata(dev);
unsigned int tpi_reg, status;
- int ret;
+ int ret, i;
ret = regmap_read(sii902x->regmap, SII902X_REG_TPI_RQB, &tpi_reg);
if (ret)
@@ -1109,7 +1120,62 @@ static int __maybe_unused sii902x_resume(struct device
*dev)
regmap_read(sii902x->regmap, SII902X_INT_STATUS, &status);
regmap_write(sii902x->regmap, SII902X_INT_STATUS, status);
+ /*
+ * Restore audio context if audio was active before suspend,
+ * in the matching order of sii902x_audio_hw_params()
+ * initialization
+ */
+ if (sii902x->audio.active) {
+ /* Re-enable mclk */
+ ret = clk_prepare_enable(sii902x->audio.mclk);
+ if (ret) {
+ dev_err(dev, "Failed to re-enable mclk: %d\n", ret);
+ return ret;
+ }
+
+ ret = regmap_write(sii902x->regmap,
SII902X_TPI_AUDIO_CONFIG_BYTE2_REG,
+ sii902x->audio.ctx_audio_config_byte2);
+ if (ret)
+ goto err_audio_resume;
+
+ ret = regmap_write(sii902x->regmap,
SII902X_TPI_I2S_INPUT_CONFIG_REG,
+ sii902x->audio.ctx_i2s_input_config);
+ if (ret)
+ goto err_audio_resume;
+
+ for (i = 0; i < ARRAY_SIZE(sii902x->audio.i2s_fifo_sequence) &&
+ sii902x->audio.i2s_fifo_sequence[i]; i++) {
+ ret = regmap_write(sii902x->regmap,
+ SII902X_TPI_I2S_ENABLE_MAPPING_REG,
+ sii902x->audio.i2s_fifo_sequence[i]);
+ if (ret)
+ goto err_audio_resume;
+ }
+
+ ret = regmap_write(sii902x->regmap,
SII902X_TPI_AUDIO_CONFIG_BYTE3_REG,
+ sii902x->audio.ctx_audio_config_byte3);
+ if (ret)
+ goto err_audio_resume;
+
+ ret = regmap_bulk_write(sii902x->regmap,
SII902X_TPI_I2S_STRM_HDR_BASE,
+ sii902x->audio.ctx_i2s_stream_header,
+ SII902X_TPI_I2S_STRM_HDR_SIZE);
+ if (ret)
+ goto err_audio_resume;
+
+ ret = regmap_bulk_write(sii902x->regmap,
SII902X_TPI_MISC_INFOFRAME_BASE,
+ sii902x->audio.ctx_audio_infoframe,
+ SII902X_TPI_MISC_INFOFRAME_SIZE);
+ if (ret)
+ goto err_audio_resume;
+ }
+
return 0;
+
+err_audio_resume:
+ clk_disable_unprepare(sii902x->audio.mclk);
+ dev_err(dev, "Failed to restore audio registers: %d\n", ret);
+ return ret;
}
static int __maybe_unused sii902x_suspend(struct device *dev)
@@ -1122,6 +1188,29 @@ static int __maybe_unused sii902x_suspend(struct device
*dev)
regmap_read(sii902x->regmap, SII902X_INT_ENABLE,
&sii902x->ctx_interrupt);
+ /*
+ * Save audio context if audio is active, and
+ * in the matching order of sii902x_audio_hw_params()
+ * initialization
+ */
+ if (sii902x->audio.active) {
+ regmap_read(sii902x->regmap, SII902X_TPI_AUDIO_CONFIG_BYTE2_REG,
+ &sii902x->audio.ctx_audio_config_byte2);
+ regmap_read(sii902x->regmap, SII902X_TPI_I2S_INPUT_CONFIG_REG,
+ &sii902x->audio.ctx_i2s_input_config);
+ regmap_read(sii902x->regmap, SII902X_TPI_AUDIO_CONFIG_BYTE3_REG,
+ &sii902x->audio.ctx_audio_config_byte3);
+ regmap_bulk_read(sii902x->regmap, SII902X_TPI_I2S_STRM_HDR_BASE,
+ sii902x->audio.ctx_i2s_stream_header,
+ SII902X_TPI_I2S_STRM_HDR_SIZE);
+ regmap_bulk_read(sii902x->regmap,
SII902X_TPI_MISC_INFOFRAME_BASE,
+ sii902x->audio.ctx_audio_infoframe,
+ SII902X_TPI_MISC_INFOFRAME_SIZE);
+
