[RFC v1 PATCH 1/3] drivers: soc: add support for soc_device_match returning -EPROBE_DEFER

[Alice Guo (OSS)]

From: Alice Guo <alice....@nxp.com>

In i.MX8M boards, the registration of SoC device is later than caam
driver which needs it. Caam driver needs soc_device_match to provide
-EPROBE_DEFER when no SoC device is registered and no
early_soc_dev_attr.

Signed-off-by: Alice Guo <alice....@nxp.com>
---
 drivers/base/soc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/base/soc.c b/drivers/base/soc.c
index 0af5363a582c..12a22f9cf5c8 100644
--- a/drivers/base/soc.c
+++ b/drivers/base/soc.c
@@ -110,6 +110,7 @@ static void soc_release(struct device *dev)
 }
 
 static struct soc_device_attribute *early_soc_dev_attr;
+static bool soc_dev_attr_init_done = false;
 
 struct soc_device *soc_device_register(struct soc_device_attribute 
*soc_dev_attr)
 {
@@ -157,6 +158,7 @@ struct soc_device *soc_device_register(struct 
soc_device_attribute *soc_dev_attr
                return ERR_PTR(ret);
        }
 
+       soc_dev_attr_init_done = true;
        return soc_dev;
 
 out3:
@@ -246,6 +248,9 @@ const struct soc_device_attribute *soc_device_match(
        if (!matches)
                return NULL;
 
+       if (!soc_dev_attr_init_done && !early_soc_dev_attr)
+               return ERR_PTR(-EPROBE_DEFER);
+
        while (!ret) {
                if (!(matches->machine || matches->family ||
                      matches->revision || matches->soc_id))
-- 
2.17.1