phy: rockchip-inno-usb2: Implement clock operations for usb2phy clock

This clock doesn't seem needed but appears in a phandle list used by
ehci-generic.c to bulk enable it. The phandle list comes from linux,
where it is needed for suspend/resume to work [1].

My tests give the same results with or without this patch, but Marek
Vasut found it weird to declare an empty clk_ops [2].

So I adapted the code from linux 6.1-rc8 so that it hopefully works
if it ever has some user. For now, without real use, it seems to
at least not give any errors when called.

Link: [1] https://lkml.kernel.org/lkml/1731551.Q6cHK6n5ZM@phil/T/
      [2] https://patchwork.ozlabs.org/project/uboot/patch/Y5IWpjYLB4aXMy9o@localhost/

Cc: Simon Glass <sjg@chromium.org>
Cc: Philipp Tomsich <philipp.tomsich@vrull.eu>
Cc: Kever Yang <kever.yang@rock-chips.com>
Cc: Lukasz Majewski <lukma@denx.de>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Christoph Fritz <chf.fritz@googlemail.com>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: Xavier Drudis Ferran <xdrudis@tinet.cat>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # rk3399, rk3328, rv1126

diff --git a/drivers/phy/rockchip/phy-rockchip-inno-usb2.c b/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
index 32145af..e43a5ba 100644 (file)
--- a/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
+++ b/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
@@ -56,6 +56,7 @@ struct rockchip_usb2phy_port_cfg {
 
 struct rockchip_usb2phy_cfg {
        unsigned int reg;
+       struct usb2phy_reg      clkout_ctl;
        const struct rockchip_usb2phy_port_cfg port_cfgs[USB2PHY_NUM_PORTS];
 };
 
@@ -77,6 +78,18 @@ static inline int property_enable(void *reg_base,
        return writel(val, reg_base + reg->offset);
 }
 
+static inline bool property_enabled(void *reg_base,
+                                   const struct usb2phy_reg *reg)
+{
+       unsigned int tmp, orig;
+       unsigned int mask = GENMASK(reg->bitend, reg->bitstart);
+
+       orig = readl(reg_base + reg->offset);
+
+       tmp = (orig & mask) >> reg->bitstart;
+       return tmp != reg->disable;
+}
+
 static const
 struct rockchip_usb2phy_port_cfg *us2phy_get_port(struct phy *phy)
 {
@@ -169,7 +182,63 @@ static struct phy_ops rockchip_usb2phy_ops = {
        .of_xlate = rockchip_usb2phy_of_xlate,
 };
 
+/**
+ * round_rate() - Adjust a rate to the exact rate a clock can provide.
+ * @clk:       The clock to manipulate.
+ * @rate:      Desidered clock rate in Hz.
+ *
+ * Return: rounded rate in Hz, or -ve error code.
+ */
+ulong rockchip_usb2phy_clk_round_rate(struct clk *clk, ulong rate)
+{
+       return 480000000;
+}
+
+/**
+ * enable() - Enable a clock.
+ * @clk:       The clock to manipulate.
+ *
+ * Return: zero on success, or -ve error code.
+ */
+int rockchip_usb2phy_clk_enable(struct clk *clk)
+{
+       struct udevice *parent = dev_get_parent(clk->dev);
+       struct rockchip_usb2phy *priv = dev_get_priv(parent);
+       const struct rockchip_usb2phy_cfg *phy_cfg = priv->phy_cfg;
+
+       /* turn on 480m clk output if it is off */
+       if (!property_enabled(priv->reg_base, &phy_cfg->clkout_ctl)) {
+               property_enable(priv->reg_base, &phy_cfg->clkout_ctl, true);
+
+               /* waiting for the clk become stable */
+               usleep_range(1200, 1300);
+       }
+
+       return 0;
+}
+
+/**
+ * disable() - Disable a clock.
+ * @clk:       The clock to manipulate.
+ *
+ * Return: zero on success, or -ve error code.
+ */
+int rockchip_usb2phy_clk_disable(struct clk *clk)
+{
+       struct udevice *parent = dev_get_parent(clk->dev);
+       struct rockchip_usb2phy *priv = dev_get_priv(parent);
+       const struct rockchip_usb2phy_cfg *phy_cfg = priv->phy_cfg;
+
+       /* turn off 480m clk output */
+       property_enable(priv->reg_base, &phy_cfg->clkout_ctl, false);
+
+       return 0;
+}
+
 static struct clk_ops rockchip_usb2phy_clk_ops = {
+       .enable = rockchip_usb2phy_clk_enable,
+       .disable = rockchip_usb2phy_clk_disable,
+       .round_rate = rockchip_usb2phy_clk_round_rate
 };
 
 static int rockchip_usb2phy_probe(struct udevice *dev)
@@ -255,8 +324,11 @@ static int rockchip_usb2phy_bind(struct udevice *dev)
        }
 
        node = dev_ofnode(dev);
-       name = ofnode_get_name(node);
-       dev_dbg(dev, "clk for node %s\n", name);
+       name = "clk_usbphy_480m";
+       dev_read_string_index(dev, "clock-output-names", 0, &name);
+
+       dev_dbg(dev, "clk %s for node %s\n", name, ofnode_get_name(node));
+
        ret = device_bind_driver_to_node(dev, "rockchip_usb2phy_clock",
                                         name, node, &usb2phy_dev);
        if (ret) {
@@ -276,6 +348,7 @@ bind_fail:
 static const struct rockchip_usb2phy_cfg rk3399_usb2phy_cfgs[] = {
        {
                .reg            = 0xe450,
+               .clkout_ctl     = { 0xe450, 4, 4, 1, 0 },
                .port_cfgs      = {
                        [USB2PHY_PORT_OTG] = {
                                .phy_sus        = { 0xe454, 1, 0, 2, 1 },
@@ -297,6 +370,7 @@ static const struct rockchip_usb2phy_cfg rk3399_usb2phy_cfgs[] = {
        },
        {
                .reg            = 0xe460,
+               .clkout_ctl     = { 0xe460, 4, 4, 1, 0 },
                .port_cfgs      = {
                        [USB2PHY_PORT_OTG] = {
                                .phy_sus        = { 0xe464, 1, 0, 2, 1 },
@@ -322,6 +396,7 @@ static const struct rockchip_usb2phy_cfg rk3399_usb2phy_cfgs[] = {
 static const struct rockchip_usb2phy_cfg rk3568_phy_cfgs[] = {
        {
                .reg            = 0xfe8a0000,
+               .clkout_ctl     = { 0x0008, 4, 4, 1, 0 },
                .port_cfgs      = {
                        [USB2PHY_PORT_OTG] = {
                                .phy_sus        = { 0x0000, 8, 0, 0x052, 0x1d1 },
@@ -347,6 +422,7 @@ static const struct rockchip_usb2phy_cfg rk3568_phy_cfgs[] = {
        },
        {
                .reg            = 0xfe8b0000,
+               .clkout_ctl     = { 0x0008, 4, 4, 1, 0 },
                .port_cfgs      = {
                        [USB2PHY_PORT_OTG] = {
                                .phy_sus        = { 0x0000, 8, 0, 0x1d2, 0x1d1 },