Re: [PATCH v10 3/4] drm/lsdc: add drm driver for loongson display controller

From: Sui Jingfeng
Date: Tue Feb 22 2022 - 09:46:47 EST



On 2022/2/22 16:27, Maxime Ripard wrote:
+ if (!of_device_is_available(output)) {
+ of_node_put(output);
+ drm_info(ddev, "connector%d is not available\n", index);
+ return NULL;
+ }
+
+ disp_tims_np = of_get_child_by_name(output, "display-timings");
+ if (disp_tims_np) {
+ lsdc_get_display_timings_from_dtb(output, &lconn->disp_tim);
+ lconn->has_disp_tim = true;
+ of_node_put(disp_tims_np);
+ drm_info(ddev, "Found display timings provided by connector%d\n", index);
+ }
+
+ connector_type = lsdc_get_connector_type(ddev, output, index);
+
+ if (output) {
+ of_node_put(output);
+ output = NULL;
+ }
+
+DT_SKIPED:
+
+ /* Only create the i2c channel if display timing is not provided */
+ if (!lconn->has_disp_tim) {
+ const struct lsdc_chip_desc * const desc = ldev->desc;
+
+ if (desc->have_builtin_i2c)
+ lconn->ddc = lsdc_create_i2c_chan(ddev, index);
+ else
+ lconn->ddc = lsdc_get_i2c_adapter(ddev, index);
This looks weird: the connector bindings have a property to store the
i2c controller connected to the DDC lines, so you should use that
instead.

This is not  weird,  ast, mgag200, hibmc do the same thing.