Re: [PATCH v5 2/5] remoteproc: imx_rproc: Populate devices under "rpmsg" subnode

Peng Fan
2025-11-06T07:55:59Z

Hi Shenwei,

It looks good to me, only a few minor comments.

On Tue, Nov 04, 2025 at 02:33:12PM -0600, Shenwei Wang wrote:
>Register the RPMsg channel driver and populate remote devices defined
>under the "rpmsg" subnode upon receiving their notification messages.
>
>The following illustrates the expected DTS layout structure:
>
> cm33: remoteproc-cm33 {
> compatible = "fsl,imx8ulp-cm33";
>
> rpmsg {
> rpmsg-io-channel {
> gpio@0 {
> compatible = "fsl,imx-rpmsg-gpio";
> reg = <0>;
> };
>
> gpio@1 {
> compatible = "fsl,imx-rpmsg-gpio";
> reg = <1>;
> };

I think better drop "imx"

>
> ...
> };
>
> rpmsg-i2c-channel {
> i2c@0 {
> compatible = "fsl,imx-rpmsg-i2c";
> reg = <0>;

i2c channel could be removed, it is not included in this patchset.

> };
> };
>
> ...
>+

....

>+static char *channel_device_map[][2] = {
>+ {"rpmsg-io-channel", "fsl,imx-rpmsg-gpio"},
>+ {"rpmsg-i2c-channel", "fsl,imx-rpmsg-i2c"},

only keep gpio and drop imx.

>+};
>+
>+static int imx_rpmsg_endpoint_cb(struct rpmsg_device *rpdev, void *data,
>+ int len, void *priv, u32 src)
>+{
>+ struct imx_rpmsg_driver_data *drvdata;
>+
>+ drvdata = dev_get_drvdata(&rpdev->dev);
>+ if (drvdata && drvdata->rx_callback)
>+ return drvdata->rx_callback(rpdev, data, len, priv, src);
>+
>+ return 0;
>+}
>+
>+static void imx_rpmsg_endpoint_remove(struct rpmsg_device *rpdev)
>+{
>+ of_platform_depopulate(&rpdev->dev);
>+}
>+
>+static int imx_rpmsg_endpoint_probe(struct rpmsg_device *rpdev)
>+{
>+ struct imx_rpmsg_driver_data *drvdata;
>+ struct imx_rpmsg_driver *imx_rpdrv;
>+ struct device *dev = &rpdev->dev;
>+ struct of_dev_auxdata *auxdata;
>+ struct rpmsg_driver *rpdrv;
>+ int i;
>+
>+ rpdrv = container_of(dev->driver, struct rpmsg_driver, drv);
>+ imx_rpdrv = container_of(rpdrv, struct imx_rpmsg_driver, rpdrv);
>+
>+ if (!imx_rpdrv->driver_data)
>+ return -EINVAL;
>+
>+ drvdata = devm_kmemdup(dev, imx_rpdrv->driver_data, sizeof(*drvdata), GFP_KERNEL);
>+ if (!drvdata)
>+ return -ENOMEM;
>+
>+ i = drvdata->map_idx;
>+ if (i >= ARRAY_SIZE(channel_device_map))
>+ return -ENODEV;
>+
>+ auxdata = devm_kzalloc(dev, sizeof(*auxdata) * 2, GFP_KERNEL);
>+ if (!auxdata)
>+ return -ENOMEM;
>+
>+ drvdata->rpdev = rpdev;
>+ auxdata[0].compatible = channel_device_map[i][1];
>+ auxdata[0].platform_data = drvdata;
>+ dev_set_drvdata(dev, drvdata);
>+
>+ of_platform_populate(drvdata->channel_node, NULL, auxdata, dev);
>+ of_node_put(drvdata->channel_node);
>+
>+ return 0;
>+}
>+
>+static int imx_of_rpmsg_is_in_map(const char *name)
>+{
>+ int i;
>+
>+ for (i = 0; i < ARRAY_SIZE(channel_device_map); i++) {
>+ if (strcmp(name, channel_device_map[i][0]) == 0)
>+ return i;
>+ }
>+
>+ return -1;
>+}
>+
>+static int imx_of_rpmsg_register_rpdriver(struct device_node *channel,
>+ struct device *dev, int idx)
>+{
>+ struct imx_rpmsg_driver_data *driver_data;
>+ struct imx_rpmsg_driver *rp_driver;
>+ struct rpmsg_device_id *rpdev_id;
>+
>+ rpdev_id = devm_kzalloc(dev, sizeof(*rpdev_id) * 2, GFP_KERNEL);
>+ if (!rpdev_id)
>+ return -ENOMEM;
>+
>+ strscpy(rpdev_id[0].name, channel_device_map[idx][0], RPMSG_NAME_SIZE);
>+
>+ rp_driver = devm_kzalloc(dev, sizeof(*rp_driver), GFP_KERNEL);
>+ if (!rp_driver)
>+ return -ENOMEM;
>+
>+ driver_data = devm_kzalloc(dev, sizeof(*driver_data), GFP_KERNEL);
>+ if (!driver_data)
>+ return -ENOMEM;
>+
>+ driver_data->rproc_name = dev->of_node->name;
>+ driver_data->channel_node = channel;
>+ driver_data->map_idx = idx;
>+
>+ rp_driver->rpdrv.drv.name = channel_device_map[idx][0];
>+ rp_driver->rpdrv.id_table = rpdev_id;
>+ rp_driver->rpdrv.probe = imx_rpmsg_endpoint_probe;
>+ rp_driver->rpdrv.remove = imx_rpmsg_endpoint_remove;
>+ rp_driver->rpdrv.callback = imx_rpmsg_endpoint_cb;
>+ rp_driver->driver_data = driver_data;
>+
>+ register_rpmsg_driver(&rp_driver->rpdrv);
>+
>+ return 0;
>+}
>+
>+static int imx_of_rpmsg_node_init(struct platform_device *pdev)
>+{
>+ struct device_node *np __free(device_node);
>+ struct device *dev = &pdev->dev;
>+ int idx, ret;
>+
>+ np = of_get_child_by_name(dev->of_node, "rpmsg");
>+ if (!np)
>+ return 0;
>+
>+ for_each_child_of_node_scoped(np, child) {
>+ idx = imx_of_rpmsg_is_in_map(child->name);
>+ if (idx < 0)
>+ ret = of_platform_default_populate(child, NULL, dev);
>+ else
>+ ret = imx_of_rpmsg_register_rpdriver(child, dev, idx);
>+
>+ if (ret < 0)
>+ return ret;
>+ }
>+
>+ return 0;
>+}
>+
> static int imx_rproc_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
>@@ -1177,6 +1319,10 @@ static int imx_rproc_probe(struct platform_device *pdev)
> goto err_put_clk;
> }
>
>+ ret = imx_of_rpmsg_node_init(pdev);
>+ if (ret < 0)
>+ dev_info(dev, "populating 'rpmsg' node failed\n");

In best case to make this generic enough, an generic function
could be provided saying rproc_of_rpmsg_node_init() in remoteproc core
or rpmsg core. But for now, it should be ok to keep it in imx_rproc.c.

Regards
Peng