[PATCH] ASoC: stm32: sai: manage identification registers

From: Olivier Moysan
Date: Mon Jun 03 2019 - 04:16:34 EST


Add support of identification registers in STM32 SAI.

Signed-off-by: Olivier Moysan <olivier.moysan@xxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
sound/soc/stm/stm32_sai.c | 44 ++++++++++++++++++++++++----
sound/soc/stm/stm32_sai.h | 54 ++++++++++++++++++++++++++---------
sound/soc/stm/stm32_sai_sub.c | 14 +++++----
3 files changed, 88 insertions(+), 24 deletions(-)

diff --git a/sound/soc/stm/stm32_sai.c b/sound/soc/stm/stm32_sai.c
index 7550d5f08be3..98b29f712831 100644
--- a/sound/soc/stm/stm32_sai.c
+++ b/sound/soc/stm/stm32_sai.c
@@ -30,13 +30,20 @@
#include "stm32_sai.h"

static const struct stm32_sai_conf stm32_sai_conf_f4 = {
- .version = SAI_STM32F4,
- .has_spdif = false,
+ .version = STM_SAI_STM32F4,
+ .fifo_size = 8,
+ .has_spdif_pdm = false,
};

+/*
+ * Default settings for stm32 H7 socs and next.
+ * These default settings will be overridden if the soc provides
+ * support of hardware configuration registers.
+ */
static const struct stm32_sai_conf stm32_sai_conf_h7 = {
- .version = SAI_STM32H7,
- .has_spdif = true,
+ .version = STM_SAI_STM32H7,
+ .fifo_size = 8,
+ .has_spdif_pdm = true,
};

static const struct of_device_id stm32_sai_ids[] = {
@@ -157,6 +164,8 @@ static int stm32_sai_probe(struct platform_device *pdev)
struct reset_control *rst;
struct resource *res;
const struct of_device_id *of_id;
+ u32 val;
+ int ret;

sai = devm_kzalloc(&pdev->dev, sizeof(*sai), GFP_KERNEL);
if (!sai)
@@ -169,7 +178,8 @@ static int stm32_sai_probe(struct platform_device *pdev)

of_id = of_match_device(stm32_sai_ids, &pdev->dev);
if (of_id)
- sai->conf = (struct stm32_sai_conf *)of_id->data;
+ memcpy(&sai->conf, (const struct stm32_sai_conf *)of_id->data,
+ sizeof(struct stm32_sai_conf));
else
return -EINVAL;

@@ -208,6 +218,30 @@ static int stm32_sai_probe(struct platform_device *pdev)
reset_control_deassert(rst);
}

+ /* Enable peripheral clock to allow register access */
+ ret = clk_prepare_enable(sai->pclk);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to enable clock: %d\n", ret);
+ return ret;
+ }
+
+ val = FIELD_GET(SAI_IDR_ID_MASK,
+ readl_relaxed(sai->base + STM_SAI_IDR));
+ if (val == SAI_IPIDR_NUMBER) {
+ val = readl_relaxed(sai->base + STM_SAI_HWCFGR);
+ sai->conf.fifo_size = FIELD_GET(SAI_HWCFGR_FIFO_SIZE, val);
+ sai->conf.has_spdif_pdm = !!FIELD_GET(SAI_HWCFGR_SPDIF_PDM,
+ val);
+
+ val = readl_relaxed(sai->base + STM_SAI_VERR);
+ sai->conf.version = val;
+
+ dev_dbg(&pdev->dev, "SAI version: %lu.%lu registered\n",
+ FIELD_GET(SAI_VERR_MAJ_MASK, val),
+ FIELD_GET(SAI_VERR_MIN_MASK, val));
+ }
+ clk_disable_unprepare(sai->pclk);
+
sai->pdev = pdev;
sai->set_sync = &stm32_sai_set_sync;
platform_set_drvdata(pdev, sai);
diff --git a/sound/soc/stm/stm32_sai.h b/sound/soc/stm/stm32_sai.h
index 9c36a393ab7b..158c73f557f7 100644
--- a/sound/soc/stm/stm32_sai.h
+++ b/sound/soc/stm/stm32_sai.h
@@ -37,6 +37,12 @@
#define STM_SAI_PDMCR_REGX 0x40
#define STM_SAI_PDMLY_REGX 0x44

+/* Hardware configuration registers */
+#define STM_SAI_HWCFGR 0x3F0
+#define STM_SAI_VERR 0x3F4
+#define STM_SAI_IDR 0x3F8
+#define STM_SAI_SIDR 0x3FC
+
/******************** Bit definition for SAI_GCR register *******************/
#define SAI_GCR_SYNCIN_SHIFT 0
#define SAI_GCR_SYNCIN_WDTH 2
@@ -82,7 +88,7 @@
#define SAI_XCR1_NODIV BIT(SAI_XCR1_NODIV_SHIFT)

#define SAI_XCR1_MCKDIV_SHIFT 20
-#define SAI_XCR1_MCKDIV_WIDTH(x) (((x) == SAI_STM32F4) ? 4 : 6)
+#define SAI_XCR1_MCKDIV_WIDTH(x) (((x) == STM_SAI_STM32F4) ? 4 : 6)
#define SAI_XCR1_MCKDIV_MASK(x) GENMASK((SAI_XCR1_MCKDIV_SHIFT + (x) - 1),\
SAI_XCR1_MCKDIV_SHIFT)
#define SAI_XCR1_MCKDIV_SET(x) ((x) << SAI_XCR1_MCKDIV_SHIFT)
@@ -234,8 +240,33 @@
#define SAI_PDMDLY_4R_MASK GENMASK(30, SAI_PDMDLY_4R_SHIFT)
#define SAI_PDMDLY_4R_WIDTH 3

-#define STM_SAI_IS_F4(ip) ((ip)->conf->version == SAI_STM32F4)
-#define STM_SAI_IS_H7(ip) ((ip)->conf->version == SAI_STM32H7)
+/* Registers below apply to SAI version 2.1 and more */
+
+/* Bit definition for SAI_HWCFGR register */
+#define SAI_HWCFGR_FIFO_SIZE GENMASK(7, 0)
+#define SAI_HWCFGR_SPDIF_PDM GENMASK(11, 8)
+#define SAI_HWCFGR_REGOUT GENMASK(19, 12)
+
+/* Bit definition for SAI_VERR register */
+#define SAI_VERR_MIN_MASK GENMASK(3, 0)
+#define SAI_VERR_MAJ_MASK GENMASK(7, 4)
+
+/* Bit definition for SAI_IDR register */
+#define SAI_IDR_ID_MASK GENMASK(31, 0)
+
+/* Bit definition for SAI_SIDR register */
+#define SAI_SIDR_ID_MASK GENMASK(31, 0)
+
+#define SAI_IPIDR_NUMBER 0x00130031
+
+/* SAI version numbers are 1.x for F4. Major version number set to 1 for F4 */
+#define STM_SAI_STM32F4 BIT(4)
+/* Dummy version number for H7 socs and next */
+#define STM_SAI_STM32H7 0x0
+
+#define STM_SAI_IS_F4(ip) ((ip)->conf.version == STM_SAI_STM32F4)
+#define STM_SAI_HAS_SPDIF_PDM(ip)\
+ ((ip)->pdata->conf.has_spdif_pdm)

enum stm32_sai_syncout {
STM_SAI_SYNC_OUT_NONE,
@@ -243,19 +274,16 @@ enum stm32_sai_syncout {
STM_SAI_SYNC_OUT_B,
};

-enum stm32_sai_version {
- SAI_STM32F4,
- SAI_STM32H7
-};
-
/**
* struct stm32_sai_conf - SAI configuration
* @version: SAI version
- * @has_spdif: SAI S/PDIF support flag
+ * @fifo_size: SAI fifo size as words number
+ * @has_spdif_pdm: SAI S/PDIF and PDM features support flag
*/
struct stm32_sai_conf {
- int version;
- bool has_spdif;
+ u32 version;
+ u32 fifo_size;
+ bool has_spdif_pdm;
};

/**
@@ -265,7 +293,7 @@ struct stm32_sai_conf {
* @pclk: SAI bus clock
* @clk_x8k: SAI parent clock for sampling frequencies multiple of 8kHz
* @clk_x11k: SAI parent clock for sampling frequencies multiple of 11kHz
- * @version: SOC version
+ * @conf: SAI hardware capabitilites
* @irq: SAI interrupt line
* @set_sync: pointer to synchro mode configuration callback
* @gcr: SAI Global Configuration Register
@@ -276,7 +304,7 @@ struct stm32_sai_data {
struct clk *pclk;
struct clk *clk_x8k;
struct clk *clk_x11k;
- struct stm32_sai_conf *conf;
+ struct stm32_sai_conf conf;
int irq;
int (*set_sync)(struct stm32_sai_data *sai,
struct device_node *np_provider, int synco, int synci);
diff --git a/sound/soc/stm/stm32_sai_sub.c b/sound/soc/stm/stm32_sai_sub.c
index 2a74ce7c9440..7d27efb19380 100644
--- a/sound/soc/stm/stm32_sai_sub.c
+++ b/sound/soc/stm/stm32_sai_sub.c
@@ -45,7 +45,6 @@
#define SAI_DATASIZE_24 0x6
#define SAI_DATASIZE_32 0x7

-#define STM_SAI_FIFO_SIZE 8
#define STM_SAI_DAI_NAME_SIZE 15

#define STM_SAI_IS_PLAYBACK(ip) ((ip)->dir == SNDRV_PCM_STREAM_PLAYBACK)
@@ -63,7 +62,8 @@
#define SAI_SYNC_EXTERNAL 0x2

#define STM_SAI_PROTOCOL_IS_SPDIF(ip) ((ip)->spdif)
-#define STM_SAI_HAS_SPDIF(x) ((x)->pdata->conf->has_spdif)
+#define STM_SAI_HAS_SPDIF(x) ((x)->pdata->conf.has_spdif_pdm)
+#define STM_SAI_HAS_PDM(x) ((x)->pdata->conf.has_spdif_pdm)
#define STM_SAI_HAS_EXT_SYNC(x) (!STM_SAI_IS_F4(sai->pdata))

#define SAI_IEC60958_BLOCK_FRAMES 192
@@ -274,7 +274,7 @@ static int stm32_sai_get_clk_div(struct stm32_sai_sub_data *sai,
unsigned long input_rate,
unsigned long output_rate)
{
- int version = sai->pdata->conf->version;
+ int version = sai->pdata->conf.version;
int div;

div = DIV_ROUND_CLOSEST(input_rate, output_rate);
@@ -295,7 +295,7 @@ static int stm32_sai_get_clk_div(struct stm32_sai_sub_data *sai,
static int stm32_sai_set_clk_div(struct stm32_sai_sub_data *sai,
unsigned int div)
{
- int version = sai->pdata->conf->version;
+ int version = sai->pdata->conf.version;
int ret, cr1, mask;

if (div > SAI_XCR1_MCKDIV_MAX(version)) {
@@ -1148,6 +1148,8 @@ static int stm32_sai_dai_probe(struct snd_soc_dai *cpu_dai)
* constraints).
*/
sai->dma_params.maxburst = 4;
+ if (sai->pdata->conf.fifo_size < 8)
+ sai->dma_params.maxburst = 1;
/* Buswidth will be set by framework at runtime */
sai->dma_params.addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;

@@ -1315,8 +1317,8 @@ static int stm32_sai_sub_parse_of(struct platform_device *pdev,
sai->phys_addr = res->start;

sai->regmap_config = &stm32_sai_sub_regmap_config_f4;
- /* Note: PDM registers not available for H7 sub-block B */
- if (STM_SAI_IS_H7(sai->pdata) && STM_SAI_IS_SUB_A(sai))
+ /* Note: PDM registers not available for sub-block B */
+ if (STM_SAI_HAS_PDM(sai) && STM_SAI_IS_SUB_A(sai))
sai->regmap_config = &stm32_sai_sub_regmap_config_h7;

sai->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "sai_ck",
--
2.20.1