[PATCHv2 4/7] phy: phy-rockchip-inno-usb2: add reset support

From: Sebastian Reichel
Date: Mon Apr 03 2023 - 16:23:24 EST


Add reset handling support, which is needed for proper
operation with RK3588.

Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
---
drivers/phy/rockchip/phy-rockchip-inno-usb2.c | 38 +++++++++++++++++++
1 file changed, 38 insertions(+)

diff --git a/drivers/phy/rockchip/phy-rockchip-inno-usb2.c b/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
index b75712bd20c9..3a78c5bf11d4 100644
--- a/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
+++ b/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
@@ -24,6 +24,7 @@
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/regmap.h>
+#include <linux/reset.h>
#include <linux/mfd/syscon.h>
#include <linux/usb/of.h>
#include <linux/usb/otg.h>
@@ -223,6 +224,7 @@ struct rockchip_usb2phy_port {
* @clk: clock struct of phy input clk.
* @clk480m: clock struct of phy output clk.
* @clk480m_hw: clock struct of phy output clk management.
+ * @phy_reset: phy reset control.
* @chg_state: states involved in USB charger detection.
* @chg_type: USB charger types.
* @dcd_retries: The retry count used to track Data contact
@@ -239,6 +241,7 @@ struct rockchip_usb2phy {
struct clk *clk;
struct clk *clk480m;
struct clk_hw clk480m_hw;
+ struct reset_control *phy_reset;
enum usb_chg_state chg_state;
enum power_supply_type chg_type;
u8 dcd_retries;
@@ -280,6 +283,25 @@ static inline bool property_enabled(struct regmap *base,
return tmp != reg->disable;
}

+static int rockchip_usb2phy_reset(struct rockchip_usb2phy *rphy)
+{
+ int ret;
+
+ ret = reset_control_assert(rphy->phy_reset);
+ if (ret)
+ return ret;
+
+ udelay(10);
+
+ ret = reset_control_deassert(rphy->phy_reset);
+ if (ret)
+ return ret;
+
+ usleep_range(100, 200);
+
+ return 0;
+}
+
static int rockchip_usb2phy_clk480m_prepare(struct clk_hw *hw)
{
struct rockchip_usb2phy *rphy =
@@ -534,6 +556,18 @@ static int rockchip_usb2phy_power_on(struct phy *phy)
return ret;
}

+ /*
+ * For rk3588, it needs to reset phy when exit from
+ * suspend mode with common_on_n 1'b1(aka REFCLK_LOGIC,
+ * Bias, and PLL blocks are powered down) for lower
+ * power consumption. If you don't want to reset phy,
+ * please keep the common_on_n 1'b0 to set these blocks
+ * remain powered.
+ */
+ ret = rockchip_usb2phy_reset(rphy);
+ if (ret)
+ return ret;
+
/* waiting for the utmi_clk to become stable */
usleep_range(1500, 2000);

@@ -1348,6 +1382,10 @@ static int rockchip_usb2phy_probe(struct platform_device *pdev)
return -EINVAL;
}

+ rphy->phy_reset = devm_reset_control_get_optional(dev, "phy");
+ if (IS_ERR(rphy->phy_reset))
+ return PTR_ERR(rphy->phy_reset);
+
rphy->clk = of_clk_get_by_name(np, "phyclk");
if (!IS_ERR(rphy->clk)) {
clk_prepare_enable(rphy->clk);
--
2.39.2