Re: [PATCH v4 2/3] reset: Add USB2PHY port reset driver for Renesas RZ/V2H(P)

From: ALOK TIWARI
Date: Mon Apr 14 2025 - 10:18:16 EST



+static int rzv2h_usbphy_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct rzv2h_usb2phy_reset_priv *priv = rzv2h_usbphy_rcdev_to_priv(rcdev);
+ struct device *dev = priv->dev;
+ int ret;
+
+ ret = pm_runtime_resume_and_get(dev);
+ if (ret) {

nit: it will good if we check similar to reset-rzg2l-usbphy-ctrl.c
pm_runtime_resume_and_get -> 0 on success, or a negative error code otherwise.
1 → if the device was resumed and incremented usage count
0 → if the device was already active or successfully resumed
if (ret < 0)

+ dev_err(dev, "pm_runtime_resume_and_get failed\n");
+ return ret;
+ }
+
+ rzv2h_usbphy_assert_helper(priv);
+
+ pm_runtime_put(dev);
+
+ return 0;
+}
+
+static int rzv2h_usbphy_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct rzv2h_usb2phy_reset_priv *priv = rzv2h_usbphy_rcdev_to_priv(rcdev);
+ const struct rzv2h_usb2phy_reset_of_data *data = priv->data;
+ struct device *dev = priv->dev;
+ int ret;
+
+ ret = pm_runtime_resume_and_get(dev);

pm_runtime_resume_and_get -> 0 on success, or a negative error code otherwise.
if (ret < 0)

+ if (ret) {
+ dev_err(dev, "pm_runtime_resume_and_get failed\n");
+ return ret;
+ }
+
+ scoped_guard(spinlock, &priv->lock) {
+ writel(data->reset_deassert_val, priv->base + data->reset_reg);
+ writel(data->reset2_release_val, priv->base + data->reset2_reg);
+ writel(data->reset_release_val, priv->base + data->reset_reg);
+ }
+
+ pm_runtime_put(dev);
+
+ return 0;
+}
+
+static int rzv2h_usbphy_reset_status(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct rzv2h_usb2phy_reset_priv *priv = rzv2h_usbphy_rcdev_to_priv(rcdev);
+ struct device *dev = priv->dev;
+ int ret;
+ u32 reg;
+
+ ret = pm_runtime_resume_and_get(dev);

pm_runtime_resume_and_get -> 0 on success, or a negative error code otherwise.
if (ret < 0)

+ if (ret) {
+ dev_err(dev, "pm_runtime_resume_and_get failed\n");
+ return ret;
+ }
+
+ reg = readl(priv->base + priv->data->reset_reg);
+
+ pm_runtime_put(dev);
+
+ return (reg & priv->data->reset_status_bits) == priv->data->reset_status_bits;
+}
+
+static const struct reset_control_ops rzv2h_usbphy_reset_ops = {
+ .assert = rzv2h_usbphy_reset_assert,
+ .deassert = rzv2h_usbphy_reset_deassert,
+ .status = rzv2h_usbphy_reset_status,
+};
+
+static int rzv2h_usb2phy_reset_of_xlate(struct reset_controller_dev *rcdev,
+ const struct of_phandle_args *reset_spec)
+{
+ /* No special handling needed, we have only one reset line per device */
+ return 0;
+}
+
+static int rzv2h_usb2phy_reset_probe(struct platform_device *pdev)
+{
+ const struct rzv2h_usb2phy_reset_of_data *data;
+ struct rzv2h_usb2phy_reset_priv *priv;
+ struct device *dev = &pdev->dev;
+ struct reset_control *rstc;
+ int error;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ data = of_device_get_match_data(dev);
+ if (!data)
+ return dev_err_probe(dev, -ENODEV,
+ "failed to match device\n");
+
+ priv->data = data;
+ priv->dev = dev;
+ priv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ rstc = devm_reset_control_get_shared_deasserted(dev, NULL);
+ if (IS_ERR(rstc))
+ return dev_err_probe(dev, PTR_ERR(rstc),
+ "failed to get deasserted reset\n");
+
+ spin_lock_init(&priv->lock);
+ dev_set_drvdata(dev, priv);
+
+ error = devm_pm_runtime_enable(dev);
+ if (error)
+ return dev_err_probe(dev, error, "Failed to enable pm_runtime\n");
+
+ error = pm_runtime_resume_and_get(dev);

nit: it will good if we check similar to reset-rzg2l-usbphy-ctrl.c
pm_runtime_resume_and_get -> 0 on success, or a negative error code otherwise.
if (error < 0)

+ if (error)
+ return dev_err_probe(dev, error, "pm_runtime_resume_and_get failed\n");
+
+ for (unsigned int i = 0; i < data->init_val_count; i++)
+ writel(data->init_vals[i].val, priv->base + data->init_vals[i].reg);
+
+ /* keep usb2phy in asserted state */
+ rzv2h_usbphy_assert_helper(priv);
+
+ pm_runtime_put(dev);
+
+ priv->rcdev.ops = &rzv2h_usbphy_reset_ops;
+ priv->rcdev.of_reset_n_cells = 0;
+ priv->rcdev.nr_resets = 1;
+ priv->rcdev.of_xlate = rzv2h_usb2phy_reset_of_xlate;
+ priv->rcdev.of_node = dev->of_node;
+ priv->rcdev.dev = dev;
+
+ return devm_reset_controller_register(dev, &priv->rcdev);
+}
+


Thanks
Alok