Re: [PATCH v4 6/9] drm-bridge: sii902x: Use fwnode API to acquire device properties

Dmitry Baryshkov
2024-04-22T20:02:34Z

On Tue, Apr 23, 2024 at 03:19:00AM +0800, Sui Jingfeng wrote:
> Make this driver less DT-dependent by calling the freshly created helper
> functions, which reduce boilerplate. Should be no functional changes for
> DT based systems.
>
> Signed-off-by: Sui Jingfeng <sui.jingfeng@linux.dev>
> ---
> drivers/gpu/drm/bridge/sii902x.c | 43 +++++++++++---------------------
> 1 file changed, 14 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
> index 8f84e98249c7..04436f318c7f 100644
> --- a/drivers/gpu/drm/bridge/sii902x.c
> +++ b/drivers/gpu/drm/bridge/sii902x.c
> @@ -827,20 +827,19 @@ static int sii902x_audio_codec_init(struct sii902x *sii902x,
> .spdif = 0,
> .max_i2s_channels = 0,
> };
> + struct fwnode_handle *fwnode = dev_fwnode(dev);
> u8 lanes[4];
> int num_lanes, i;
>
> - if (!of_property_read_bool(dev->of_node, "#sound-dai-cells")) {
> + if (!fwnode_property_present(fwnode, "#sound-dai-cells")) {
> dev_dbg(dev, "%s: No \"#sound-dai-cells\", no audio\n",
> __func__);
> return 0;
> }
>
> - num_lanes = of_property_read_variable_u8_array(dev->of_node,
> - "sil,i2s-data-lanes",
> - lanes, 1,
> - ARRAY_SIZE(lanes));
> -
> + num_lanes = fwnode_property_read_u8_array(fwnode,
> + "sil,i2s-data-lanes",
> + lanes, ARRAY_SIZE(lanes));

You have lost support for having less than 4 lanes. Please see the
documentation for this function.

> if (num_lanes == -EINVAL) {
> dev_dbg(dev,
> "%s: No \"sil,i2s-data-lanes\", use default <0>\n",
> @@ -1097,13 +1096,13 @@ static int sii902x_init(struct sii902x *sii902x)
> goto err_unreg_audio;
>
> sii902x->bridge.funcs = &sii902x_bridge_funcs;
> - sii902x->bridge.of_node = dev->of_node;
> sii902x->bridge.timings = &default_sii902x_timings;
> sii902x->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID;
>
> if (sii902x->i2c->irq > 0)
> sii902x->bridge.ops |= DRM_BRIDGE_OP_HPD;
>
> + drm_bridge_set_node(&sii902x->bridge, dev_fwnode(dev));

Move back to the place of the of_node setter.

> drm_bridge_add(&sii902x->bridge);
>
> return 0;
> @@ -1118,7 +1117,6 @@ static int sii902x_init(struct sii902x *sii902x)
> static int sii902x_probe(struct i2c_client *client)
> {
> struct device *dev = &client->dev;
> - struct device_node *endpoint;
> struct sii902x *sii902x;
> static const char * const supplies[] = {"iovcc", "cvcc12"};
> int ret;
> @@ -1147,27 +1145,14 @@ static int sii902x_probe(struct i2c_client *client)
> return PTR_ERR(sii902x->reset_gpio);
> }
>
> - endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 1, -1);
> - if (endpoint) {
> - struct device_node *remote = of_graph_get_remote_port_parent(endpoint);
> -
> - of_node_put(endpoint);
> - if (!remote) {
> - dev_err(dev, "Endpoint in port@1 unconnected\n");
> - return -ENODEV;
> - }
> -
> - if (!of_device_is_available(remote)) {
> - dev_err(dev, "port@1 remote device is disabled\n");
> - of_node_put(remote);
> - return -ENODEV;
> - }
> -
> - sii902x->next_bridge = of_drm_find_bridge(remote);
> - of_node_put(remote);
> - if (!sii902x->next_bridge)
> - return dev_err_probe(dev, -EPROBE_DEFER,
> - "Failed to find remote bridge\n");
> + sii902x->next_bridge = drm_bridge_find_next_bridge_by_fwnode(dev_fwnode(dev), 1);
> + if (!sii902x->next_bridge) {
> + return dev_err_probe(dev, -EPROBE_DEFER,
> + "Failed to find the next bridge\n");
> + } else if (IS_ERR(sii902x->next_bridge)) {
> + ret = PTR_ERR(sii902x->next_bridge);
> + dev_err(dev, "Error on find the next bridge: %d\n", ret);
> + return ret;
> }
>
> mutex_init(&sii902x->mutex);
> --
> 2.34.1
>

--
With best wishes
Dmitry