Re: [PATCH 3/8] drm/bridge: it66121: Add a helper function to read bus width

Dmitry Baryshkov
2023-11-14T16:04:04Z

On Tue, 14 Nov 2023 at 17:09, Sui Jingfeng <sui.jingfeng@linux.dev> wrote:
>
> From: Sui Jingfeng <suijingfeng@loongson.cn>
>
> Group those relavent code lines (which with common purpose) into one helper
> function, suppress the dependency on DT to function level. Just trivial
> cleanup, no functional change.
>
> Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
> ---
> drivers/gpu/drm/bridge/ite-it66121.c | 32 ++++++++++++++++++++--------
> 1 file changed, 23 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/ite-it66121.c b/drivers/gpu/drm/bridge/ite-it66121.c
> index 83dbdbfc9ed8..0f78737adc83 100644
> --- a/drivers/gpu/drm/bridge/ite-it66121.c
> +++ b/drivers/gpu/drm/bridge/ite-it66121.c
> @@ -320,6 +320,26 @@ static inline struct it66121_ctx *bridge_to_it66121(struct drm_bridge *bridge)
> return container_of(bridge, struct it66121_ctx, bridge);
> }
>
> +static int it66121_of_read_bus_width(struct device *dev, u32 *bus_width)

Using a pointer to return int value doesn't look right. Just return a
signed int here and if it is not an error, assign it to ctx->bus_width

> +{
> + struct device_node *np;
> + u32 bw;
> +
> + np = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
> + if (!np)
> + return -EINVAL;
> +
> + of_property_read_u32(np, "bus-width", &bw);
> + of_node_put(np);
> +
> + if (bw != 12 && bw != 24)
> + return -EINVAL;
> +
> + *bus_width = bw;
> +
> + return 0;
> +}
> +
> static const struct regmap_range_cfg it66121_regmap_banks[] = {
> {
> .name = "it66121",
> @@ -1525,19 +1545,13 @@ static int it66121_probe(struct i2c_client *client)
> if (!ctx)
> return -ENOMEM;
>
> - ep = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
> - if (!ep)
> - return -EINVAL;
> -
> ctx->dev = dev;
> ctx->client = client;
> ctx->info = i2c_get_match_data(client);
>
> - of_property_read_u32(ep, "bus-width", &ctx->bus_width);
> - of_node_put(ep);
> -
> - if (ctx->bus_width != 12 && ctx->bus_width != 24)
> - return -EINVAL;
> + ret = it66121_of_read_bus_width(dev, &ctx->bus_width);
> + if (ret)
> + return ret;
>
> ep = of_graph_get_remote_node(dev->of_node, 1, -1);
> if (!ep) {
> --
> 2.34.1
>

--
With best wishes
Dmitry