[PATCH] pinctrl: core: Handling pinmux and pinconf separately

[PATCH] pinctrl: core: Handling pinmux and pinconf separately

[Michal Simek]

Right now the handling order depends on how entries are coming which is
corresponding with order in DT. We have reached the case with DT overlays
where conf and mux descriptions are exchanged which ends up in sequence
that firmware has been asked to perform configuration before requesting the
pin.
The patch is enforcing the order that pin is requested all the time first
followed by pin configuration. This change will ensure that firmware gets
requests in the right order.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
---

 drivers/pinctrl/core.c | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index 7d3370289938..f5c32d2a3c91 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -1258,13 +1258,34 @@ static int pinctrl_commit_state(struct pinctrl *p, struct pinctrl_state *state)
 
 	p->state = NULL;
 
-	/* Apply all the settings for the new state */
+	/* Apply all the settings for the new state - pinmux first */
 	list_for_each_entry(setting, &state->settings, node) {
 		switch (setting->type) {
 		case PIN_MAP_TYPE_MUX_GROUP:
 			ret = pinmux_enable_setting(setting);
 			break;
 		case PIN_MAP_TYPE_CONFIGS_PIN:
+		case PIN_MAP_TYPE_CONFIGS_GROUP:
+			break;
+		default:
+			ret = -EINVAL;
+			break;
+		}
+
+		if (ret < 0)
+			goto unapply_new_state;
+
+		/* Do not link hogs (circular dependency) */
+		if (p != setting->pctldev->p)
+			pinctrl_link_add(setting->pctldev, p->dev);
+	}
+
+	/* Apply all the settings for the new state - pinconf after */
+	list_for_each_entry(setting, &state->settings, node) {
+		switch (setting->type) {
+		case PIN_MAP_TYPE_MUX_GROUP:
+			break;
+		case PIN_MAP_TYPE_CONFIGS_PIN:
 		case PIN_MAP_TYPE_CONFIGS_GROUP:
 			ret = pinconf_apply_setting(setting);
 			break;
-- 
2.30.1

Re: [PATCH] pinctrl: core: Handling pinmux and pinconf separately

[Linus Walleij]

On Wed, Mar 10, 2021 at 9:16 AM Michal Simek <michal.simek@xilinx.com> wrote:

> Right now the handling order depends on how entries are coming which is
> corresponding with order in DT. We have reached the case with DT overlays
> where conf and mux descriptions are exchanged which ends up in sequence
> that firmware has been asked to perform configuration before requesting the
> pin.
> The patch is enforcing the order that pin is requested all the time first
> followed by pin configuration. This change will ensure that firmware gets
> requests in the right order.
>
> Signed-off-by: Michal Simek <michal.simek@xilinx.com>

This looks right to me so I simply applied the patch so it  gets some
testing in linux-next.

If there are problems on some platform(s) we will get to know.

Yours,
Linus Walleij