Some StarFive peripherals have 5 resets that need to be triggered in
order. Add a helper to simplify this. The Linux way of doing this would
be to import the reset_control_array API, but device_reset_all as
implemented here saves us from this boilerplate.
Signed-off-by: Ahmad Fatoum <a.fat...@pengutronix.de>
---
drivers/reset/core.c | 78 +++++++++++++++++++++++++++++++++++++------
include/linux/reset.h | 7 ++++
2 files changed, 75 insertions(+), 10 deletions(-)
diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index 26a54f21dff0..940b46d4b4bd 100644
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -139,30 +139,35 @@ int reset_control_deassert(struct reset_control *rstc)
EXPORT_SYMBOL_GPL(reset_control_deassert);
/**
- * of_reset_control_get - Lookup and obtain a reference to a reset controller.
+ * of_reset_control_count - Count reset lines
+ * @node: device node
+ *
+ * Returns number of resets, 0 if none specified
+ */
+static int of_reset_control_count(struct device_node *node)
+{
+ return of_count_phandle_with_args(node, "resets", "#reset-cells");
+}
+
+/**
+ * of_reset_control_get_by_index - Lookup and obtain a reference to a reset
controller.
* @node: device to be reset by the controller
- * @id: reset line name
+ * @index: reset line index
*
* Returns a struct reset_control or IS_ERR() condition containing errno.
- *
- * Use of id names is optional.
*/
-static struct reset_control *of_reset_control_get(struct device_node *node,
- const char *id)
+static struct reset_control *of_reset_control_get_by_index(struct device_node
*node,
+ int index)
{
struct reset_control *rstc;
struct reset_controller_dev *r, *rcdev;
struct of_phandle_args args;
- int index = 0;
int rstc_id;
int ret;
if (!of_get_property(node, "resets", NULL))
return NULL;
- if (id)
- index = of_property_match_string(node,
- "reset-names", id);
ret = of_parse_phandle_with_args(node, "resets", "#reset-cells",
index, &args);
if (ret)
@@ -195,6 +200,26 @@ static struct reset_control *of_reset_control_get(struct
device_node *node,
return rstc;
}
+/**
+ * of_reset_control_get - Lookup and obtain a reference to a reset controller.
+ * @node: device to be reset by the controller
+ * @id: reset line name
+ *
+ * Returns a struct reset_control or IS_ERR() condition containing errno.
+ *
+ * Use of id names is optional.
+ */
+static struct reset_control *of_reset_control_get(struct device_node *node,
+ const char *id)
+{
+ int index = 0;
+
+ if (id)
+ index = of_property_match_string(node, "reset-names", id);
+
+ return of_reset_control_get_by_index(node, index);
+}
+
static struct reset_control *
gpio_reset_control_get(struct device_d *dev, const char *id)
{
@@ -302,6 +327,39 @@ int device_reset(struct device_d *dev)
}
EXPORT_SYMBOL_GPL(device_reset);
+int device_reset_all(struct device_d *dev)
+{
+ struct reset_control *rstc;
+ int ret, i;
+
+ for (i = 0; i < of_reset_control_count(dev->device_node); i++) {
+ int ret;
+
+ rstc = of_reset_control_get_by_index(dev->device_node, i);
+ if (IS_ERR(rstc))
+ return PTR_ERR(rstc);
+
+ ret = reset_control_reset(rstc);
+ if (ret)
+ return ret;
+
+ reset_control_put(rstc);
+ }
+
+ if (i == 0) {
+ rstc = gpio_reset_control_get(dev, NULL);
+
+ ret = reset_control_reset(rstc);
+ if (ret)
+ return ret;
+
+ reset_control_put(rstc);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(device_reset_all);
+
int device_reset_us(struct device_d *dev, int us)
{
struct reset_control *rstc;
diff --git a/include/linux/reset.h b/include/linux/reset.h
index a166fe1cfe04..0a98ea6bacdf 100644
--- a/include/linux/reset.h
+++ b/include/linux/reset.h
@@ -17,6 +17,8 @@ int __must_check device_reset(struct device_d *dev);
int __must_check device_reset_us(struct device_d *dev, int us);
+int __must_check device_reset_all(struct device_d *dev);
+
#else
static inline int reset_control_reset(struct reset_control *rstc)
@@ -54,6 +56,11 @@ static inline int device_reset(struct device_d *dev)
return 0;
}
+static inline int device_reset_all(struct device_d *dev)
+{
+ return 0;
+}
+
#endif /* CONFIG_RESET_CONTROLLER */
#endif
--
2.29.2
_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox
