[PATCH] ASoC: amd: add logic to check dmic hardware runtime

[Vijendar Mukunda <Vijendar.Mukunda@xxxxxxx>]

Add logic to check DMIC hardware exists or not on
the platform at runtime.

Add module param for overriding DMIC hardware check
at runtime.

Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@xxxxxxx>
---
 sound/soc/amd/renoir/rn-pci-acp3x.c | 29 +++++++++++++++++++++++++++++
 sound/soc/amd/renoir/rn_acp3x.h     |  2 ++
 2 files changed, 31 insertions(+)

diff --git a/sound/soc/amd/renoir/rn-pci-acp3x.c b/sound/soc/amd/renoir/rn-pci-acp3x.c
index 859ed67..faa7566 100644
--- a/sound/soc/amd/renoir/rn-pci-acp3x.c
+++ b/sound/soc/amd/renoir/rn-pci-acp3x.c
@@ -5,6 +5,7 @@
 //Copyright 2020 Advanced Micro Devices, Inc.
 
 #include <linux/pci.h>
+#include <linux/acpi.h>
 #include <linux/module.h>
 #include <linux/io.h>
 #include <linux/delay.h>
@@ -18,6 +19,16 @@ static int acp_power_gating;
 module_param(acp_power_gating, int, 0644);
 MODULE_PARM_DESC(acp_power_gating, "Enable acp power gating");
 
+/**
+ * dmic_acpi_check = -1 - Checks ACPI method to know DMIC hardware status runtime
+ *                 = 0 - Skips the DMIC device creation and returns probe failure
+ *                 = 1 - Assumes that platform has DMIC support and skips ACPI
+ *                       method check
+ */
+static int dmic_acpi_check = ACP_DMIC_AUTO;
+module_param(dmic_acpi_check, int, 0644);
+MODULE_PARM_DESC(dmic_acpi_check, "checks Dmic hardware runtime");
+
 struct acp_dev_data {
 	void __iomem *acp_base;
 	struct resource *res;
@@ -157,6 +168,8 @@ static int snd_rn_acp_probe(struct pci_dev *pci,
 {
 	struct acp_dev_data *adata;
 	struct platform_device_info pdevinfo[ACP_DEVS];
+	acpi_handle handle;
+	acpi_integer dmic_status;
 	unsigned int irqflags;
 	int ret, index;
 	u32 addr;
@@ -201,6 +214,22 @@ static int snd_rn_acp_probe(struct pci_dev *pci,
 	if (ret)
 		goto disable_msi;
 
+	if (!dmic_acpi_check) {
+		ret = -ENODEV;
+		goto de_init;
+	} else if (dmic_acpi_check == ACP_DMIC_AUTO) {
+		handle = ACPI_HANDLE(&pci->dev);
+		ret = acpi_evaluate_integer(handle, "_WOV", NULL, &dmic_status);
+		if (ACPI_FAILURE(ret)) {
+			ret = -EINVAL;
+			goto de_init;
+		}
+		if (!dmic_status) {
+			ret = -ENODEV;
+			goto de_init;
+		}
+	}
+
 	adata->res = devm_kzalloc(&pci->dev,
 				  sizeof(struct resource) * 2,
 				  GFP_KERNEL);
diff --git a/sound/soc/amd/renoir/rn_acp3x.h b/sound/soc/amd/renoir/rn_acp3x.h
index 75228e3..1462039 100644
--- a/sound/soc/amd/renoir/rn_acp3x.h
+++ b/sound/soc/amd/renoir/rn_acp3x.h
@@ -55,6 +55,8 @@
 
 #define MAX_BUFFER (CAPTURE_MAX_PERIOD_SIZE * CAPTURE_MAX_NUM_PERIODS)
 #define MIN_BUFFER MAX_BUFFER
+#define	ACP_DMIC_AUTO   -1
+
 struct pdm_dev_data {
 	u32 pdm_irq;
 	void __iomem *acp_base;
-- 
2.7.4