ASoC: stm32: sai: Add synchronization support
Add Synchronization support for STM32 SAI.
Signed-off-by: olivier moysan <olivier.moysan@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/stm/stm32_sai.c b/sound/soc/stm/stm32_sai.c
index 5fe878ac..d6f71a3 100644
--- a/sound/soc/stm/stm32_sai.c
+++ b/sound/soc/stm/stm32_sai.c
@@ -16,6 +16,7 @@
* details.
*/
+#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/module.h>
@@ -27,6 +28,16 @@
#include "stm32_sai.h"
+static LIST_HEAD(sync_providers);
+static DEFINE_MUTEX(sync_mutex);
+
+struct sync_provider {
+ struct list_head link;
+ struct device_node *node;
+ int (*sync_conf)(void *data, int synco);
+ void *data;
+};
+
static const struct stm32_sai_conf stm32_sai_conf_f4 = {
.version = SAI_STM32F4,
};
@@ -41,23 +52,143 @@ static const struct of_device_id stm32_sai_ids[] = {
{}
};
+static int stm32_sai_sync_conf_client(struct stm32_sai_data *sai, int synci)
+{
+ int ret;
+
+ /* Enable peripheral clock to allow GCR register access */
+ ret = clk_prepare_enable(sai->pclk);
+ if (ret) {
+ dev_err(&sai->pdev->dev, "failed to enable clock: %d\n", ret);
+ return ret;
+ }
+
+ writel_relaxed(FIELD_PREP(SAI_GCR_SYNCIN_MASK, (synci - 1)), sai->base);
+
+ clk_disable_unprepare(sai->pclk);
+
+ return 0;
+}
+
+static int stm32_sai_sync_conf_provider(void *data, int synco)
+{
+ struct stm32_sai_data *sai = (struct stm32_sai_data *)data;
+ u32 prev_synco;
+ int ret;
+
+ /* Enable peripheral clock to allow GCR register access */
+ ret = clk_prepare_enable(sai->pclk);
+ if (ret) {
+ dev_err(&sai->pdev->dev, "failed to enable clock: %d\n", ret);
+ return ret;
+ }
+
+ dev_dbg(&sai->pdev->dev, "Set %s%s as synchro provider\n",
+ sai->pdev->dev.of_node->name,
+ synco == STM_SAI_SYNC_OUT_A ? "A" : "B");
+
+ prev_synco = FIELD_GET(SAI_GCR_SYNCOUT_MASK, readl_relaxed(sai->base));
+ if (prev_synco != STM_SAI_SYNC_OUT_NONE && synco != prev_synco) {
+ dev_err(&sai->pdev->dev, "%s%s already set as sync provider\n",
+ sai->pdev->dev.of_node->name,
+ prev_synco == STM_SAI_SYNC_OUT_A ? "A" : "B");
+ clk_disable_unprepare(sai->pclk);
+ return -EINVAL;
+ }
+
+ writel_relaxed(FIELD_PREP(SAI_GCR_SYNCOUT_MASK, synco), sai->base);
+
+ clk_disable_unprepare(sai->pclk);
+
+ return 0;
+}
+
+static int stm32_sai_set_sync_provider(struct device_node *np, int synco)
+{
+ struct sync_provider *provider;
+ int ret;
+
+ mutex_lock(&sync_mutex);
+ list_for_each_entry(provider, &sync_providers, link) {
+ if (provider->node == np) {
+ ret = provider->sync_conf(provider->data, synco);
+ mutex_unlock(&sync_mutex);
+ return ret;
+ }
+ }
+ mutex_unlock(&sync_mutex);
+
+ /* SAI sync provider not found */
+ return -ENODEV;
+}
+
+static int stm32_sai_set_sync(struct stm32_sai_data *sai,
+ struct device_node *np_provider,
+ int synco, int synci)
+{
+ int ret;
+
+ /* Configure sync client */
+ stm32_sai_sync_conf_client(sai, synci);
+
+ /* Configure sync provider */
+ ret = stm32_sai_set_sync_provider(np_provider, synco);
+
+ return ret;
+}
+
+static int stm32_sai_sync_add_provider(struct platform_device *pdev,
+ void *data)
+{
+ struct sync_provider *sp;
+
+ sp = devm_kzalloc(&pdev->dev, sizeof(*sp), GFP_KERNEL);
+ if (!sp)
+ return -ENOMEM;
+
+ sp->node = of_node_get(pdev->dev.of_node);
+ sp->data = data;
+ sp->sync_conf = &stm32_sai_sync_conf_provider;
+
+ mutex_lock(&sync_mutex);
+ list_add(&sp->link, &sync_providers);
+ mutex_unlock(&sync_mutex);
+
+ return 0;
+}
+
+static void stm32_sai_sync_del_provider(struct device_node *np)
+{
+ struct sync_provider *sp;
+
+ mutex_lock(&sync_mutex);
+ list_for_each_entry(sp, &sync_providers, link) {
+ if (sp->node == np) {
+ list_del(&sp->link);
+ of_node_put(sp->node);
+ break;
+ }
+ }
+ mutex_unlock(&sync_mutex);
+}
+
static int stm32_sai_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct stm32_sai_data *sai;
struct reset_control *rst;
struct resource *res;
- void __iomem *base;
const struct of_device_id *of_id;
+ int ret;
sai = devm_kzalloc(&pdev->dev, sizeof(*sai), GFP_KERNEL);
if (!sai)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- base = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(base))
- return PTR_ERR(base);
+ sai->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(sai->base))
+ return PTR_ERR(sai->base);
of_id = of_match_device(stm32_sai_ids, &pdev->dev);
if (of_id)
@@ -65,6 +196,14 @@ static int stm32_sai_probe(struct platform_device *pdev)
else
return -EINVAL;
+ if (!STM_SAI_IS_F4(sai)) {
+ sai->pclk = devm_clk_get(&pdev->dev, "pclk");
+ if (IS_ERR(sai->pclk)) {
+ dev_err(&pdev->dev, "missing bus clock pclk\n");
+ return PTR_ERR(sai->pclk);
+ }
+ }
+
sai->clk_x8k = devm_clk_get(&pdev->dev, "x8k");
if (IS_ERR(sai->clk_x8k)) {
dev_err(&pdev->dev, "missing x8k parent clock\n");
@@ -92,16 +231,27 @@ static int stm32_sai_probe(struct platform_device *pdev)
reset_control_deassert(rst);
}
+ ret = stm32_sai_sync_add_provider(pdev, sai);
+ if (ret < 0)
+ return ret;
+ sai->set_sync = &stm32_sai_set_sync;
+
sai->pdev = pdev;
platform_set_drvdata(pdev, sai);
- return of_platform_populate(np, NULL, NULL, &pdev->dev);
+ ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
+ if (ret < 0)
+ stm32_sai_sync_del_provider(np);
+
+ return ret;
}
static int stm32_sai_remove(struct platform_device *pdev)
{
of_platform_depopulate(&pdev->dev);
+ stm32_sai_sync_del_provider(pdev->dev.of_node);
+
return 0;
}