Re: [PATCH 4/8] drm/bridge: it66121: Add a helper function to get the next bridge

Sui Jingfeng
2023-11-23T05:25:21Z

Hi,

On 2023/11/15 00:05, Dmitry Baryshkov wrote:
> On Tue, 14 Nov 2023 at 17:09, Sui Jingfeng <sui.jingfeng@linux.dev> wrote:
>> From: Sui Jingfeng <suijingfeng@loongson.cn>
>>
>> Group the code lines(which with the same functional) into one dedicated
>> function, which reduce the weight of it66121_probe() function. Just trivial
>> cleanuo, no functional change.
>>
>> Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
>> ---
>> drivers/gpu/drm/bridge/ite-it66121.c | 53 ++++++++++++++++++----------
>> 1 file changed, 34 insertions(+), 19 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/ite-it66121.c b/drivers/gpu/drm/bridge/ite-it66121.c
>> index 0f78737adc83..7e473beefc79 100644
>> --- a/drivers/gpu/drm/bridge/ite-it66121.c
>> +++ b/drivers/gpu/drm/bridge/ite-it66121.c
>> @@ -340,6 +340,37 @@ static int it66121_of_read_bus_width(struct device *dev, u32 *bus_width)
>> return 0;
>> }
>>
>> +static int it66121_of_get_next_bridge(struct device *dev,
>> + struct drm_bridge **next_bridge)
> it already exists and it is called drm_of_find_panel_or_bridge(),
> could you please use it instead?

That function is too fat and tangled, and should be untangled.
it66121 can not connect with a panel, this is a prior knowledge
and is known at compile time. So this prior knowledge shouldn't
be dropped.

>> +{
>> + struct device_node *np;
>> + struct drm_bridge *bridge;
>> +
>> + np = of_graph_get_remote_node(dev->of_node, 1, -1);
>> + if (!np) {
>> + dev_err(dev, "The endpoint is unconnected\n");
>> + return -EINVAL;
>> + }
>> +
>> + if (!of_device_is_available(np)) {
>> + of_node_put(np);
>> + dev_err(dev, "The remote device is disabled\n");
>> + return -ENODEV;
>> + }
>> +
>> + bridge = of_drm_find_bridge(np);
>> + of_node_put(np);
>> +
>> + if (!bridge) {
>> + dev_dbg(dev, "Next bridge not found, deferring probe\n");
>> + return -EPROBE_DEFER;
>> + }
>> +
>> + *next_bridge = bridge;
>> +
>> + return 0;
>> +}
>> +
>> static const struct regmap_range_cfg it66121_regmap_banks[] = {
>> {
>> .name = "it66121",
>> @@ -1531,7 +1562,6 @@ static const char * const it66121_supplies[] = {
>> static int it66121_probe(struct i2c_client *client)
>> {
>> u32 revision_id, vendor_ids[2] = { 0 }, device_ids[2] = { 0 };
>> - struct device_node *ep;
>> int ret;
>> struct it66121_ctx *ctx;
>> struct device *dev = &client->dev;
>> @@ -1553,24 +1583,9 @@ static int it66121_probe(struct i2c_client *client)
>> if (ret)
>> return ret;
>>
>> - ep = of_graph_get_remote_node(dev->of_node, 1, -1);
>> - if (!ep) {
>> - dev_err(dev, "The endpoint is unconnected\n");
>> - return -EINVAL;
>> - }
>> -
>> - if (!of_device_is_available(ep)) {
>> - of_node_put(ep);
>> - dev_err(dev, "The remote device is disabled\n");
>> - return -ENODEV;
>> - }
>> -
>> - ctx->next_bridge = of_drm_find_bridge(ep);
>> - of_node_put(ep);
>> - if (!ctx->next_bridge) {
>> - dev_dbg(dev, "Next bridge not found, deferring probe\n");
>> - return -EPROBE_DEFER;
>> - }
>> + ret = it66121_of_get_next_bridge(dev, &ctx->next_bridge);
>> + if (ret)
>> + return ret;
>>
>> i2c_set_clientdata(client, ctx);
>> mutex_init(&ctx->lock);
>> --
>> 2.34.1
>>
>