[PATCH v4 5/8] reset: starfive: Introduce active_low

Changhuang Liang <[email protected]> Sat, 8 Aug 2026 18:50:51 -0700
Newsgroups org.kernel.vger.linux-clk,org.infradead.lists.linux-riscv,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
The JHB100 SoC supports inverted operations for reset
assertion/deassertion, introducing an active_low field to distinguish
between different operation logics.

Signed-off-by: Changhuang Liang <[email protected]>
---
 drivers/reset/starfive/reset-starfive-common.c | 6 +++++-
 drivers/reset/starfive/reset-starfive-common.h | 6 ++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/reset/starfive/reset-starfive-common.c b/drivers/reset/starfive/reset-starfive-common.c
index 86dbb33bb216..7723520637ca 100644
--- a/drivers/reset/starfive/reset-starfive-common.c
+++ b/drivers/reset/starfive/reset-starfive-common.c
@@ -52,12 +52,16 @@ static int starfive_reset_update(struct reset_controller_dev *rcdev,
 				 unsigned long id, bool assert)
 {
 	struct starfive_reset *data = starfive_reset_from(rcdev);
+	bool active_low = data->info && data->info->active_low;
 	unsigned long offset, flags;
 	void __iomem *reg_assert;
 	void __iomem *reg_status;
 	u32 mask, done, value;
 	int ret;
 
+	if (active_low)
+		assert = !assert;
+
 	if (data->info && data->info->discontiguous) {
 		id = starfive_reset_id_to_hw_id(data->info->map, data->info->nr_resets, id);
 		if (id == STARFIVE_RESET_ID_INVALID)
@@ -70,7 +74,7 @@ static int starfive_reset_update(struct reset_controller_dev *rcdev,
 	reg_status = data->status + offset * sizeof(u32);
 	done = data->asserted ? data->asserted[offset] & mask : 0;
 
-	if (!assert)
+	if (active_low == assert)
 		done ^= mask;
 
 	spin_lock_irqsave(&data->lock, flags);
diff --git a/drivers/reset/starfive/reset-starfive-common.h b/drivers/reset/starfive/reset-starfive-common.h
index 0d4e634de58e..c7f80e744700 100644
--- a/drivers/reset/starfive/reset-starfive-common.h
+++ b/drivers/reset/starfive/reset-starfive-common.h
@@ -15,6 +15,12 @@ struct starfive_reset_info {
 	unsigned int nr_resets;
 	unsigned int assert_offset;
 	unsigned int status_offset;
+
+	/* If active_low is false, setting the bit to 1 asserts
+	 * the signal while clearing it to 0 deasserts it, and vice
+	 * versa.
+	 */
+	bool active_low;
 	bool discontiguous;
 	const struct starfive_reset_map *map;
 };
-- 
2.25.1