[PATCH 6/6] ASoC: amd: ps: Add a module parameter to influence pdm_gain

From: Mario Limonciello
Date: Fri Jan 27 2023 - 11:03:25 EST


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.

Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
sound/soc/amd/ps/acp63.h | 2 +-
sound/soc/amd/ps/ps-pdm-dma.c | 7 ++++++-
2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/sound/soc/amd/ps/acp63.h b/sound/soc/amd/ps/acp63.h
index bae8288d8231c..bed4d51e226a5 100644
--- a/sound/soc/amd/ps/acp63.h
+++ b/sound/soc/amd/ps/acp63.h
@@ -30,7 +30,7 @@
#define ACP_ERROR_STAT 29
#define PDM_DECIMATION_FACTOR 2
#define ACP_PDM_CLK_FREQ_MASK 7
-#define ACP_WOV_MISC_CTRL_MASK 0x18
+#define ACP_WOV_GAIN_CONTROL GENMASK(4, 3)
#define ACP_PDM_ENABLE 1
#define ACP_PDM_DISABLE 0
#define ACP_PDM_DMA_EN_STATUS 2
diff --git a/sound/soc/amd/ps/ps-pdm-dma.c b/sound/soc/amd/ps/ps-pdm-dma.c
index eea71a9d2ef1a..1e773c5496c5f 100644
--- a/sound/soc/amd/ps/ps-pdm-dma.c
+++ b/sound/soc/amd/ps/ps-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_ps_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 acp63_pdm_hardware_capture = {
.info = SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_BLOCK_TRANSFER |
@@ -55,7 +60,7 @@ static void acp63_enable_pdm_clock(void __iomem *acp_base)

acp63_writel(pdm_clk_enable, acp_base + ACP_WOV_CLK_CTRL);
pdm_ctrl = acp63_readl(acp_base + ACP_WOV_MISC_CTRL);
- pdm_ctrl |= ACP_WOV_MISC_CTRL_MASK;
+ pdm_ctrl |= FIELD_PREP(ACP_WOV_GAIN_CONTROL, pdm_gain);
acp63_writel(pdm_ctrl, acp_base + ACP_WOV_MISC_CTRL);
}

--
2.34.1