From 89216494ae23dc0071a2b7f8d8264cee55cc211d Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Tue, 11 Dec 2012 14:14:32 +0100 Subject: [PATCH] pinctrl: skip deferral of hogs Up until now, as hogs were always taken at the end of the pin control device registration, it didn't cause any problem. But when starting to hog pins from the device core it will cause deferral of the pin controller device itself since the default pin fetch is done *before* the device probes, so let's fix this annoyance (which is also aesthetically ugly). Also take some care to make sure that if any one map entry results in a deferral rather than a failure, then that deferral will take precedence. Reviewed-by: Stephen Warren Signed-off-by: Linus Walleij --- drivers/pinctrl/core.c | 27 ++++++++++++++++++++++++--- 1 file changed, 24 insertions(+), 3 deletions(-) diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index 59f5a965bdc4..5b4885c27d12 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -609,13 +609,16 @@ static int add_setting(struct pinctrl *p, struct pinctrl_map const *map) setting->pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name); if (setting->pctldev == NULL) { - dev_info(p->dev, "unknown pinctrl device %s in map entry, deferring probe", - map->ctrl_dev_name); kfree(setting); + /* Do not defer probing of hogs (circular loop) */ + if (!strcmp(map->ctrl_dev_name, map->dev_name)) + return -ENODEV; /* * OK let us guess that the driver is not there yet, and * let's defer obtaining this pinctrl handle to later... */ + dev_info(p->dev, "unknown pinctrl device %s in map entry, deferring probe", + map->ctrl_dev_name); return -EPROBE_DEFER; } @@ -694,11 +697,29 @@ static struct pinctrl *create_pinctrl(struct device *dev) continue; ret = add_setting(p, map); - if (ret < 0) { + /* + * At this point the adding of a setting may: + * + * - Defer, if the pinctrl device is not yet available + * - Fail, if the pinctrl device is not yet available, + * AND the setting is a hog. We cannot defer that, since + * the hog will kick in immediately after the device + * is registered. + * + * If the error returned was not -EPROBE_DEFER then we + * accumulate the errors to see if we end up with + * an -EPROBE_DEFER later, as that is the worst case. + */ + if (ret == -EPROBE_DEFER) { pinctrl_put_locked(p, false); return ERR_PTR(ret); } } + if (ret < 0) { + /* If some other error than deferral occured, return here */ + pinctrl_put_locked(p, false); + return ERR_PTR(ret); + } /* Add the pinctrl handle to the global list */ list_add_tail(&p->node, &pinctrl_list);