dm: reset: Update uclass to allow querying reset status

Add a reset operations function pointer to support querying the current
status of a reset control.

Reviewed-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Andreas Dannenberg <dannenberg@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>

drivers/reset/reset-uclass.c

@@ -192,6 +192,15 @@ int reset_deassert_bulk(struct reset_ctl_bulk *bulk)
 	return 0;
 }
 
+int reset_status(struct reset_ctl *reset_ctl)
+{
+	struct reset_ops *ops = reset_dev_ops(reset_ctl->dev);
+
+	debug("%s(reset_ctl=%p)\n", __func__, reset_ctl);
+
+	return ops->rst_status(reset_ctl);
+}
+
 int reset_release_all(struct reset_ctl *reset_ctl, int count)
 {
 	int i, ret;

include/reset-uclass.h

@@ -76,6 +76,14 @@ struct reset_ops {
 	 * @return 0 if OK, or a negative error code.
 	 */
 	int (*rst_deassert)(struct reset_ctl *reset_ctl);
+	/**
+	 * rst_status - Check reset signal status.
+	 *
+	 * @reset_ctl:	The reset signal to check.
+	 * @return 0 if deasserted, positive if asserted, or a negative
+	 *           error code.
+	 */
+	int (*rst_status)(struct reset_ctl *reset_ctl);
 };
 
 #endif

include/reset.h

@@ -207,6 +207,15 @@ int reset_deassert(struct reset_ctl *reset_ctl);
 int reset_deassert_bulk(struct reset_ctl_bulk *bulk);
 
 /**
+ * rst_status - Check reset signal status.
+ *
+ * @reset_ctl:	The reset signal to check.
+ * @return 0 if deasserted, positive if asserted, or a negative
+ *           error code.
+ */
+int reset_status(struct reset_ctl *reset_ctl);
+
+/**
  * reset_release_all - Assert/Free an array of previously requested resets.
  *
  * For each reset contained in the reset array, this function will check if
@@ -279,6 +288,11 @@ static inline int reset_deassert_bulk(struct reset_ctl_bulk *bulk)
 	return 0;
 }
 
+static inline int reset_status(struct reset_ctl *reset_ctl)
+{
+	return -ENOTSUPP;
+}
+
 static inline int reset_release_all(struct reset_ctl *reset_ctl, int count)
 {
 	return 0;