Re: [PATCH 1/2] pinctrl: Allow a device to indicate when to force a state
From: Charles Keepax <ckeepax@opensource.cirrus.com>
Date: 2017-09-22 12:47:18
Also in:
linux-gpio, lkml
On Wed, Sep 20, 2017 at 06:04:20PM -0700, Florian Fainelli wrote:
quoted hunk ↗ jump to hunk
It may happen that a device needs to force applying a state, e.g: because it only defines one state of pin states (default) but loses power/register contents when entering low power modes. Add a pinctrl_dev::flags bitmask to help describe future quirks and define PINCTRL_FLG_FORCE_STATE as such a settable flag. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> --- drivers/pinctrl/core.c | 15 +++++++++++++++ drivers/pinctrl/core.h | 4 ++++ 2 files changed, 19 insertions(+)diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index 56fbe4c3e800..c450a97de88f 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c@@ -1197,11 +1197,26 @@ int pinctrl_select_state(struct pinctrl *p, struct pinctrl_state *state) { struct pinctrl_setting *setting, *setting2; struct pinctrl_state *old_state = p->state; + bool force = false; int ret; if (p->state == state) return 0;
I am guessing you probably intended to remove these two lines.
+ if (p->state) {
+ list_for_each_entry(setting, &p->state->settings, node) {
+ if (setting->pctldev->flags & PINCTRL_FLG_FORCE_STATE)
+ force = true;
+ }
+ }
+
+ /* Some controllers may want to force this operation when they define
+ * only one set of functions and lose power state, e.g: pinctrl-single
+ * with its pinctrl-single,low-power-state-loss property.
+ */
+ if (p->state == state && !force)
+ return 0;
+Thanks, Charles