On 9/22/22 15:59, Quentin Schulz wrote:
Hi Marek,
Hi,
[...]
diff --git a/doc/README.gpio b/doc/README.gpio index 548ff37b8cc..d253f654fad 100644 --- a/doc/README.gpio +++ b/doc/README.gpio @@ -2,10 +2,8 @@ GPIO hog (CONFIG_GPIO_HOG) -------- -All the GPIO hog are initialized in gpio_hog_probe_all() function called in -board_r.c just before board_late_init() but you can also acces directly to -the gpio with gpio_hog_lookup_name().
+All the GPIO hog are initialized using DM_FLAG_PROBE_AFTER_BIND DM flag +after bind(). Example, for the device tree: diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index 0ed32b72170..32df0448a7b 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -315,34 +315,11 @@ static int gpio_hog_probe(struct udevice *dev) return 0; } -int gpio_hog_probe_all(void) -{ - struct udevice *dev; - int ret; - int retval = 0;
- for (uclass_first_device(UCLASS_NOP, &dev); - dev; - uclass_find_next_device(&dev)) { - if (dev->driver == DM_DRIVER_GET(gpio_hog)) { - ret = device_probe(dev); - if (ret) { - printf("Failed to probe device %s err: %d\n", - dev->name, ret); - retval = ret; - } - } - }
- return retval; -}
int gpio_hog_lookup_name(const char *name, struct gpio_desc **desc) { struct udevice *dev; *desc = NULL; - gpio_hog_probe_all(); if (!uclass_get_device_by_name(UCLASS_NOP, name, &dev)) { struct gpio_hog_priv *priv = dev_get_priv(dev); @@ -1503,6 +1480,8 @@ static int gpio_post_bind(struct udevice *dev) &child); if (ret) return ret;
+ dev_or_flags(child, DM_FLAG_PROBE_AFTER_BIND);
I replaced this line with:
+ /* + * Make sure gpio-hogs are probed after bind + * since hogs can be essential to the hardware + * system. + */ + dev_or_flags(child, DM_FLAG_PROBE_AFTER_BIND);
+ /* + * Since gpio-hog is a U_BOOT_DRIVER and not + * a U_BOOT_CLASS, the DM core does not bind + * it and therefore it's up to this driver to + * set the DM_FLAG_PRE_RELOC appropriately. + */ + if (ofnode_pre_reloc(node)) + dev_or_flags(child, DM_FLAG_PRE_RELOC);
This second part should be handled by the DM, or you need dm-pre-reloc in your GPIO controller in DT. This would fail e.g. in case your GPIO controller has higher depth of hog subnodes, like:
gpio-controller { something { gpio-hog { u-boot,dm-pre-reloc; }; }; };
Should really be:
gpio-controller { u-boot,dm-pre-reloc; something { u-boot,dm-pre-reloc; gpio-hog { u-boot,dm-pre-reloc; }; }; };
At some point, I had the idea to instead of littering the DT with u-boot,dm-pre-reloc , we could use phandles instead and do something like:
/ { config { u-boot,dm-pre-reloc = <&node1 &node2 ... &gpio_hog ...>; }; } ... gpio-controller { something { gpio_hog: gpio-hog { }; }; };