On 27. 05. 19 11:36, Heiko Schocher wrote:
Hello Michal,
Am 27.05.2019 um 09:13 schrieb Michal Simek:
On 27. 05. 19 8:30, Heiko Schocher wrote:
add gpio-hog support. GPIO hogging is a mechanism providing automatic GPIO request and configuration as part of the gpio-controller's driver probe function.
for more infos see: doc/device-tree-bindings/gpio/gpio.txt
Signed-off-by: Heiko Schocher hs@denx.de
I have tested it on zcu102 where I use gpio hogs for gt muxes.
Thanks!
gpio hogs are handled and setup only when gpio controller is probed.
Yes, with my current approach ... If you need a gpio-hog in a gpio device, wich is not used, you can add in board code:
gpio_hog_lookup_name("name_of_the_gpio_hog");
and gpio driver (and gpio hogs) get probed ... but not really nice...
Do we have a way how to say that controllers with gpio hogs should be probed automatically?
No yet, but I am open for suggestions ;-)
Right now you are calling it in post_probe which make sense but on the other hand if you find gpio hog in bind you should probe the whole driver without asking for request.
Yes, I also thought about this approach, but the problem is in
static int gpio_hog(struct udevice *dev) { ofnode node; struct gpio_dev_priv *uc_priv = NULL;
uc_priv = dev_get_uclass_priv(dev); if (!uc_priv) { printf("%s: missing private data.\n", __func__); return -EINVAL; }
uc_priv is not valid @bind stage ...
But I can think of a function which scans all gpio nodes for gpio hog subnodes, and call device_probe() ?
But from where should this function be called?
The question is if this patch is reading that gpio-hogs at right stage. Right now you are decoding them in post_probe. Normally getting information from DT is done in ofdata_to_platdata. It is question if this approach is also working for non DT case.
Anyway let's say you setup a flag in ofdata_to_platdata that there are gpio hogs and then you know if you should probe that device or not.
btw: didn't send this before you v2 but should be still valid. Let me test v2 now.
M