On 30. 01. 23 23:07, Mario Limonciello wrote:
In case of regressions for any users that the new pdm_gain value is
too high and for additional debugging, introduce a module parameter
that would let them configure it.
This parameter should be removed in the future:
* If it's determined that the parameter is not needed, just hardcode
the correct value as before
* If users do end up using it to debug and report different values
we should introduce a config knob that can have policy set by ucm.
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
v1->v2:
* Add a guard for values > 3 to overflow the FIELD_PREP
* Clear ACP_WOV_GAIN_CONTROL before setting it
---
sound/soc/amd/yc/acp6x-pdm-dma.c | 10 +++++++++-
sound/soc/amd/yc/acp6x.h | 2 +-
2 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/sound/soc/amd/yc/acp6x-pdm-dma.c b/sound/soc/amd/yc/acp6x-pdm-dma.c
index acecd6a4ec4b1..2bb3ea14bae9c 100644
--- a/sound/soc/amd/yc/acp6x-pdm-dma.c
+++ b/sound/soc/amd/yc/acp6x-pdm-dma.c
@@ -7,6 +7,7 @@
#include <linux/platform_device.h>
#include <linux/module.h>
+#include <linux/bitfield.h>
#include <linux/err.h>
#include <linux/io.h>
#include <sound/pcm_params.h>
@@ -18,6 +19,10 @@
#define DRV_NAME "acp_yc_pdm_dma"
+static int pdm_gain = 3;
+module_param(pdm_gain, int, 0644);
+MODULE_PARM_DESC(pdm_gain, "Gain control (0-3)");
+
static const struct snd_pcm_hardware acp6x_pdm_hardware_capture = {
.info = SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_BLOCK_TRANSFER |
@@ -55,7 +60,10 @@ static void acp6x_enable_pdm_clock(void __iomem *acp_base)
acp6x_writel(pdm_clk_enable, acp_base + ACP_WOV_CLK_CTRL);
pdm_ctrl = acp6x_readl(acp_base + ACP_WOV_MISC_CTRL);
- pdm_ctrl |= ACP_WOV_MISC_CTRL_MASK;
+ pdm_ctrl &= FIELD_PREP(ACP_WOV_GAIN_CONTROL, 0);
It should be 'pdm_ctrl &= ~ACP_WOV_GAIN_CONTROL' see include/linux/bitfield.h
(Modify: comment).
+ if (pdm_gain > 3)
+ pdm_gain = 3;
Negative values are not handled. Use clamp(pdm_gain, 0, 3) - see
include/linux/minmax.h.
+ pdm_ctrl |= FIELD_PREP(ACP_WOV_GAIN_CONTROL, pdm_gain);
acp6x_writel(pdm_ctrl, acp_base + ACP_WOV_MISC_CTRL);
Jaroslav
--
Jaroslav Kysela <perex@xxxxxxxx>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.
