Hi
Am 27.06.25 um 09:56 schrieb Javier Martinez Canillas:
Luca Weiss <[email protected]> writes:
Some devices might require keeping an interconnect path alive so that
the framebuffer continues working. Add support for that by setting the
bandwidth requirements appropriately for all provided interconnect
paths.
Reviewed-by: Thomas Zimmermann <[email protected]>
Signed-off-by: Luca Weiss <[email protected]>
---
drivers/video/fbdev/simplefb.c | 83 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 83 insertions(+)
[...]
+static void simplefb_detach_icc(void *res)
+{
+ struct simplefb_par *par = res;
+ int i;
+
+ for (i = par->icc_count - 1; i >= 0; i--) {
+ if (!IS_ERR_OR_NULL(par->icc_paths[i]))
+ icc_put(par->icc_paths[i]);
+ }
+}
+
+static int simplefb_attach_icc(struct simplefb_par *par,
+ struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ int ret, count, i;
+
+ count = of_count_phandle_with_args(dev->of_node, "interconnects",
+ "#interconnect-cells");
+ if (count < 0)
+ return 0;
+
+ /* An interconnect path consists of two elements */
+ if (count % 2) {
+ dev_err(dev, "invalid interconnects value\n");
+ return -EINVAL;
+ }
+ par->icc_count = count / 2;
+
+ par->icc_paths = devm_kcalloc(dev, par->icc_count,
+ sizeof(*par->icc_paths),
+ GFP_KERNEL);
+ if (!par->icc_paths)
+ return -ENOMEM;
+
+ for (i = 0; i < par->icc_count; i++) {
+ par->icc_paths[i] = of_icc_get_by_index(dev, i);
+ if (IS_ERR_OR_NULL(par->icc_paths[i])) {
+ ret = PTR_ERR(par->icc_paths[i]);
+ if (ret == -EPROBE_DEFER)
+ goto err;
+ dev_err(dev, "failed to get interconnect path %u:
%d\n", i, ret);
+ continue;
+ }
+
+ ret = icc_set_bw(par->icc_paths[i], 0, UINT_MAX);
+ if (ret) {
+ dev_err(dev, "failed to set interconnect bandwidth %u:
%d\n", i, ret);
+ continue;
+ }
+ }
+
+ return devm_add_action_or_reset(dev, simplefb_detach_icc, par);
+
+err:
+ while (i) {
+ --i;
+ if (!IS_ERR_OR_NULL(par->icc_paths[i]))
+ icc_put(par->icc_paths[i]);
+ }
+ return ret;
+}
+#else
These two functions contain the same logic that you are using in the
simpledrm driver. I wonder if could be made helpers so that the code
isn't duplicated in both drivers.
No please not!. Any work should rather be directed towards deleting
simplefb entirely.
Best regards
Thomas
But in any case it could be a follow-up of your series I think.
Reviewed-by: Javier Martinez Canillas <[email protected]>
--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)
