ASoC: stm32: spdifrx: manage identification registers

Add support of identification registers in STM32 SPDIFRX.
Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/stm/stm32_spdifrx.c

@@ -16,6 +16,7 @@
  * details.
  */
 
+#include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/completion.h>
 #include <linux/delay.h>
@@ -36,6 +37,9 @@
 #define STM32_SPDIFRX_DR	0x10
 #define STM32_SPDIFRX_CSR	0x14
 #define STM32_SPDIFRX_DIR	0x18
+#define STM32_SPDIFRX_VERR	0x3F4
+#define STM32_SPDIFRX_IDR	0x3F8
+#define STM32_SPDIFRX_SIDR	0x3FC
 
 /* Bit definition for SPDIF_CR register */
 #define SPDIFRX_CR_SPDIFEN_SHIFT	0
@@ -169,6 +173,18 @@
 #define SPDIFRX_SPDIFEN_SYNC	0x1
 #define SPDIFRX_SPDIFEN_ENABLE	0x3
 
+/* Bit definition for SPDIFRX_VERR register */
+#define SPDIFRX_VERR_MIN_MASK	GENMASK(3, 0)
+#define SPDIFRX_VERR_MAJ_MASK	GENMASK(7, 4)
+
+/* Bit definition for SPDIFRX_IDR register */
+#define SPDIFRX_IDR_ID_MASK	GENMASK(31, 0)
+
+/* Bit definition for SPDIFRX_SIDR register */
+#define SPDIFRX_SIDR_SID_MASK	GENMASK(31, 0)
+
+#define SPDIFRX_IPIDR_NUMBER	0x00130041
+
 #define SPDIFRX_IN1		0x1
 #define SPDIFRX_IN2		0x2
 #define SPDIFRX_IN3		0x3
@@ -607,6 +623,9 @@ static bool stm32_spdifrx_readable_reg(struct device *dev, unsigned int reg)
 	case STM32_SPDIFRX_DR:
 	case STM32_SPDIFRX_CSR:
 	case STM32_SPDIFRX_DIR:
+	case STM32_SPDIFRX_VERR:
+	case STM32_SPDIFRX_IDR:
+	case STM32_SPDIFRX_SIDR:
 		return true;
 	default:
 		return false;
@@ -642,10 +661,11 @@ static const struct regmap_config stm32_h7_spdifrx_regmap_conf = {
 	.reg_bits = 32,
 	.reg_stride = 4,
 	.val_bits = 32,
-	.max_register = STM32_SPDIFRX_DIR,
+	.max_register = STM32_SPDIFRX_SIDR,
 	.readable_reg = stm32_spdifrx_readable_reg,
 	.volatile_reg = stm32_spdifrx_volatile_reg,
 	.writeable_reg = stm32_spdifrx_writeable_reg,
+	.num_reg_defaults_raw = STM32_SPDIFRX_SIDR / sizeof(u32) + 1,
 	.fast_io = true,
 	.cache_type = REGCACHE_FLAT,
 };
@@ -911,6 +931,7 @@ static int stm32_spdifrx_probe(struct platform_device *pdev)
 	struct stm32_spdifrx_data *spdifrx;
 	struct reset_control *rst;
 	const struct snd_dmaengine_pcm_config *pcm_config = NULL;
+	u32 ver, idr;
 	int ret;
 
 	spdifrx = devm_kzalloc(&pdev->dev, sizeof(*spdifrx), GFP_KERNEL);
@@ -967,7 +988,19 @@ static int stm32_spdifrx_probe(struct platform_device *pdev)
 		goto error;
 	}
 
-	return 0;
+	ret = regmap_read(spdifrx->regmap, STM32_SPDIFRX_IDR, &idr);
+	if (ret)
+		goto error;
+
+	if (idr == SPDIFRX_IPIDR_NUMBER) {
+		ret = regmap_read(spdifrx->regmap, STM32_SPDIFRX_VERR, &ver);
+
+		dev_dbg(&pdev->dev, "SPDIFRX version: %lu.%lu registered\n",
+			FIELD_GET(SPDIFRX_VERR_MAJ_MASK, ver),
+			FIELD_GET(SPDIFRX_VERR_MIN_MASK, ver));
+	}
+
+	return ret;
 
 error:
 	if (!IS_ERR(spdifrx->ctrl_chan))