From 42fed7ba44e4e8c1fb27b28ad14490cb1daff3c7 Mon Sep 17 00:00:00 2001 From: Patrice Chotard Date: Thu, 11 Apr 2013 11:01:27 +0200 Subject: [PATCH] pinctrl: move subsystem mutex to pinctrl_dev struct This mutex avoids deadlock in case of use of multiple pin controllers. Before this modification, by using a global mutex, deadlock appeared when, for example, a call to pinctrl_pins_show() locked the pinctrl_mutex, called the ops->pin_dbg_show of a particular pin controller. If this pin controller needs I2C access to retrieve configuration information and I2C driver is using pinctrl to drive its pins, a call to pinctrl_select_state() try to lock again pinctrl_mutex which leads to a deadlock. Notice that the mutex grab from the two direction functions was moved into pinctrl_gpio_direction(). For several cases, we can't replace pinctrl_mutex by pctldev->mutex, because at this stage, pctldev is not accessible : - pinctrl_get()/pinctrl_put() - pinctrl_register_maps() So add respectively pinctrl_list_mutex and pinctrl_maps_mutex in order to protect pinctrl_list and pinctrl_maps list instead. Reintroduce pinctrldev_list_mutex in find_pinctrl_by_of_node(), pinctrl_find_and_add_gpio_range() pinctrl_request_gpio(), pinctrl_free_gpio(), pinctrl_gpio_direction(), pinctrl_devices_show(), pinctrl_register() and pinctrl_unregister() to protect pinctrldev_list. Changes v2->v3: - Fix a missing EXPORT_SYMBOL_GPL() for pinctrl_select_state(). Changes v1->v2: - pinctrl_select_state_locked() is removed, all lock mechanism is located inside pinctrl_select_state(). When parsing the state->setting list, take the per-pin-controller driver lock. (Patrice). - Introduce pinctrldev_list_mutex to protect pinctrldev_list in all functions which parse or modify pictrldev_list. (Patrice). - move find_pinctrl_by_of_node() from pinctrl/devicetree.c to pinctrl/core.c in order to protect pinctrldev_list. (Patrice). - Sink mutex:es into some functions and remove some _locked variants down to where the lists are actually accessed to make things simpler. (Linus) - Drop *all* mutexes completely from pinctrl_lookup_state() and pinctrl_select_state() - no relevant mutex was taken and it was unclear what this was protecting against. (Linus) Reported by : Seraphin Bonnaffe Signed-off-by: Patrice Chotard Signed-off-by: Linus Walleij --- drivers/pinctrl/core.c | 265 +++++++++++++++++++++++-------------------- drivers/pinctrl/core.h | 6 +- drivers/pinctrl/devicetree.c | 15 +-- drivers/pinctrl/pinconf.c | 46 ++++---- drivers/pinctrl/pinmux.c | 8 +- 5 files changed, 176 insertions(+), 164 deletions(-) diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index 8b832ce..c3d222e 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -40,11 +40,17 @@ static bool pinctrl_dummy_state; -/* Mutex taken by all entry points */ -DEFINE_MUTEX(pinctrl_mutex); +/* Mutex taken to protect pinctrl_list */ +DEFINE_MUTEX(pinctrl_list_mutex); + +/* Mutex taken to protect pinctrl_maps */ +DEFINE_MUTEX(pinctrl_maps_mutex); + +/* Mutex taken to protect pinctrldev_list */ +DEFINE_MUTEX(pinctrldev_list_mutex); /* Global list of pin control devices (struct pinctrl_dev) */ -LIST_HEAD(pinctrldev_list); +static LIST_HEAD(pinctrldev_list); /* List of pin controller handles (struct pinctrl) */ static LIST_HEAD(pinctrl_list); @@ -111,6 +117,23 @@ struct pinctrl_dev *get_pinctrl_dev_from_devname(const char *devname) return found ? pctldev : NULL; } +struct pinctrl_dev *get_pinctrl_dev_from_of_node(struct device_node *np) +{ + struct pinctrl_dev *pctldev; + + mutex_lock(&pinctrldev_list_mutex); + + list_for_each_entry(pctldev, &pinctrldev_list, node) + if (pctldev->dev->of_node == np) { + mutex_unlock(&pinctrldev_list_mutex); + return pctldev; + } + + mutex_lock(&pinctrldev_list_mutex); + + return NULL; +} + /** * pin_get_from_name() - look up a pin number from a name * @pctldev: the pin control device to lookup the pin on @@ -170,9 +193,9 @@ bool pin_is_valid(struct pinctrl_dev *pctldev, int pin) if (pin < 0) return false; - mutex_lock(&pinctrl_mutex); + mutex_lock(&pctldev->mutex); pindesc = pin_desc_get(pctldev, pin); - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return pindesc != NULL; } @@ -269,15 +292,17 @@ pinctrl_match_gpio_range(struct pinctrl_dev *pctldev, unsigned gpio) { struct pinctrl_gpio_range *range = NULL; + mutex_lock(&pctldev->mutex); /* Loop over the ranges */ list_for_each_entry(range, &pctldev->gpio_ranges, node) { /* Check if we're in the valid range */ if (gpio >= range->base && gpio < range->base + range->npins) { + mutex_unlock(&pctldev->mutex); return range; } } - + mutex_unlock(&pctldev->mutex); return NULL; } @@ -361,9 +386,9 @@ static int pinctrl_get_device_gpio_range(unsigned gpio, void pinctrl_add_gpio_range(struct pinctrl_dev *pctldev, struct pinctrl_gpio_range *range) { - mutex_lock(&pinctrl_mutex); + mutex_lock(&pctldev->mutex); list_add_tail(&range->node, &pctldev->gpio_ranges); - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); } EXPORT_SYMBOL_GPL(pinctrl_add_gpio_range); @@ -381,17 +406,25 @@ EXPORT_SYMBOL_GPL(pinctrl_add_gpio_ranges); struct pinctrl_dev *pinctrl_find_and_add_gpio_range(const char *devname, struct pinctrl_gpio_range *range) { - struct pinctrl_dev *pctldev = get_pinctrl_dev_from_devname(devname); + struct pinctrl_dev *pctldev; + + mutex_lock(&pinctrldev_list_mutex); + + pctldev = get_pinctrl_dev_from_devname(devname); /* * If we can't find this device, let's assume that is because * it has not probed yet, so the driver trying to register this * range need to defer probing. */ - if (!pctldev) + if (!pctldev) { + mutex_unlock(&pinctrldev_list_mutex); return ERR_PTR(-EPROBE_DEFER); - + } pinctrl_add_gpio_range(pctldev, range); + + mutex_unlock(&pinctrldev_list_mutex); + return pctldev; } EXPORT_SYMBOL_GPL(pinctrl_find_and_add_gpio_range); @@ -407,14 +440,17 @@ pinctrl_find_gpio_range_from_pin(struct pinctrl_dev *pctldev, { struct pinctrl_gpio_range *range = NULL; + mutex_lock(&pctldev->mutex); /* Loop over the ranges */ list_for_each_entry(range, &pctldev->gpio_ranges, node) { /* Check if we're in the valid range */ if (pin >= range->pin_base && pin < range->pin_base + range->npins) { + mutex_unlock(&pctldev->mutex); return range; } } + mutex_unlock(&pctldev->mutex); return NULL; } @@ -428,9 +464,9 @@ EXPORT_SYMBOL_GPL(pinctrl_find_gpio_range_from_pin); void pinctrl_remove_gpio_range(struct pinctrl_dev *pctldev, struct pinctrl_gpio_range *range) { - mutex_lock(&pinctrl_mutex); + mutex_lock(&pctldev->mutex); list_del(&range->node); - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); } EXPORT_SYMBOL_GPL(pinctrl_remove_gpio_range); @@ -481,13 +517,13 @@ int pinctrl_request_gpio(unsigned gpio) int ret; int pin; - mutex_lock(&pinctrl_mutex); + mutex_lock(&pinctrldev_list_mutex); ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range); if (ret) { if (pinctrl_ready_for_gpio_range(gpio)) ret = 0; - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pinctrldev_list_mutex); return ret; } @@ -496,7 +532,7 @@ int pinctrl_request_gpio(unsigned gpio) ret = pinmux_request_gpio(pctldev, range, pin, gpio); - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pinctrldev_list_mutex); return ret; } EXPORT_SYMBOL_GPL(pinctrl_request_gpio); @@ -516,20 +552,22 @@ void pinctrl_free_gpio(unsigned gpio) int ret; int pin; - mutex_lock(&pinctrl_mutex); + mutex_lock(&pinctrldev_list_mutex); ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range); if (ret) { - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pinctrldev_list_mutex); return; } + mutex_lock(&pctldev->mutex); /* Convert to the pin controllers number space */ pin = gpio - range->base + range->pin_base; pinmux_free_gpio(pctldev, pin, range); - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); + mutex_unlock(&pinctrldev_list_mutex); } EXPORT_SYMBOL_GPL(pinctrl_free_gpio); @@ -540,14 +578,24 @@ static int pinctrl_gpio_direction(unsigned gpio, bool input) int ret; int pin; + mutex_lock(&pinctrldev_list_mutex); + ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range); - if (ret) + if (ret) { + mutex_unlock(&pinctrldev_list_mutex); return ret; + } + + mutex_lock(&pctldev->mutex); /* Convert to the pin controllers number space */ pin = gpio - range->base + range->pin_base; + ret = pinmux_gpio_direction(pctldev, range, pin, input); + + mutex_unlock(&pctldev->mutex); + mutex_unlock(&pinctrldev_list_mutex); - return pinmux_gpio_direction(pctldev, range, pin, input); + return ret; } /** @@ -560,11 +608,7 @@ static int pinctrl_gpio_direction(unsigned gpio, bool input) */ int pinctrl_gpio_direction_input(unsigned gpio) { - int ret; - mutex_lock(&pinctrl_mutex); - ret = pinctrl_gpio_direction(gpio, true); - mutex_unlock(&pinctrl_mutex); - return ret; + return pinctrl_gpio_direction(gpio, true); } EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_input); @@ -578,11 +622,7 @@ EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_input); */ int pinctrl_gpio_direction_output(unsigned gpio) { - int ret; - mutex_lock(&pinctrl_mutex); - ret = pinctrl_gpio_direction(gpio, false); - mutex_unlock(&pinctrl_mutex); - return ret; + return pinctrl_gpio_direction(gpio, false); } EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_output); @@ -685,14 +725,18 @@ static struct pinctrl *find_pinctrl(struct device *dev) { struct pinctrl *p; + mutex_lock(&pinctrl_list_mutex); list_for_each_entry(p, &pinctrl_list, node) - if (p->dev == dev) + if (p->dev == dev) { + mutex_unlock(&pinctrl_list_mutex); return p; + } + mutex_unlock(&pinctrl_list_mutex); return NULL; } -static void pinctrl_put_locked(struct pinctrl *p, bool inlist); +static void pinctrl_free(struct pinctrl *p, bool inlist); static struct pinctrl *create_pinctrl(struct device *dev) { @@ -725,6 +769,7 @@ static struct pinctrl *create_pinctrl(struct device *dev) devname = dev_name(dev); + mutex_lock(&pinctrl_maps_mutex); /* Iterate over the pin control maps to locate the right ones */ for_each_maps(maps_node, i, map) { /* Map must be for this device */ @@ -746,13 +791,16 @@ static struct pinctrl *create_pinctrl(struct device *dev) * an -EPROBE_DEFER later, as that is the worst case. */ if (ret == -EPROBE_DEFER) { - pinctrl_put_locked(p, false); + pinctrl_free(p, false); + mutex_unlock(&pinctrl_maps_mutex); return ERR_PTR(ret); } } + mutex_unlock(&pinctrl_maps_mutex); + if (ret < 0) { /* If some other error than deferral occured, return here */ - pinctrl_put_locked(p, false); + pinctrl_free(p, false); return ERR_PTR(ret); } @@ -764,7 +812,11 @@ static struct pinctrl *create_pinctrl(struct device *dev) return p; } -static struct pinctrl *pinctrl_get_locked(struct device *dev) +/** + * pinctrl_get() - retrieves the pinctrl handle for a device + * @dev: the device to obtain the handle for + */ +struct pinctrl *pinctrl_get(struct device *dev) { struct pinctrl *p; @@ -785,21 +837,6 @@ static struct pinctrl *pinctrl_get_locked(struct device *dev) return create_pinctrl(dev); } - -/** - * pinctrl_get() - retrieves the pinctrl handle for a device - * @dev: the device to obtain the handle for - */ -struct pinctrl *pinctrl_get(struct device *dev) -{ - struct pinctrl *p; - - mutex_lock(&pinctrl_mutex); - p = pinctrl_get_locked(dev); - mutex_unlock(&pinctrl_mutex); - - return p; -} EXPORT_SYMBOL_GPL(pinctrl_get); static void pinctrl_free_setting(bool disable_setting, @@ -820,11 +857,12 @@ static void pinctrl_free_setting(bool disable_setting, } } -static void pinctrl_put_locked(struct pinctrl *p, bool inlist) +static void pinctrl_free(struct pinctrl *p, bool inlist) { struct pinctrl_state *state, *n1; struct pinctrl_setting *setting, *n2; + mutex_lock(&pinctrl_list_mutex); list_for_each_entry_safe(state, n1, &p->states, node) { list_for_each_entry_safe(setting, n2, &state->settings, node) { pinctrl_free_setting(state == p->state, setting); @@ -840,6 +878,7 @@ static void pinctrl_put_locked(struct pinctrl *p, bool inlist) if (inlist) list_del(&p->node); kfree(p); + mutex_unlock(&pinctrl_list_mutex); } /** @@ -850,7 +889,7 @@ static void pinctrl_release(struct kref *kref) { struct pinctrl *p = container_of(kref, struct pinctrl, users); - pinctrl_put_locked(p, true); + pinctrl_free(p, true); } /** @@ -859,14 +898,17 @@ static void pinctrl_release(struct kref *kref) */ void pinctrl_put(struct pinctrl *p) { - mutex_lock(&pinctrl_mutex); kref_put(&p->users, pinctrl_release); - mutex_unlock(&pinctrl_mutex); } EXPORT_SYMBOL_GPL(pinctrl_put); -static struct pinctrl_state *pinctrl_lookup_state_locked(struct pinctrl *p, - const char *name) +/** + * pinctrl_lookup_state() - retrieves a state handle from a pinctrl handle + * @p: the pinctrl handle to retrieve the state from + * @name: the state name to retrieve + */ +struct pinctrl_state *pinctrl_lookup_state(struct pinctrl *p, + const char *name) { struct pinctrl_state *state; @@ -883,26 +925,14 @@ static struct pinctrl_state *pinctrl_lookup_state_locked(struct pinctrl *p, return state; } +EXPORT_SYMBOL_GPL(pinctrl_lookup_state); /** - * pinctrl_lookup_state() - retrieves a state handle from a pinctrl handle - * @p: the pinctrl handle to retrieve the state from - * @name: the state name to retrieve + * pinctrl_select_state() - select/activate/program a pinctrl state to HW + * @p: the pinctrl handle for the device that requests configuration + * @state: the state handle to select/activate/program */ -struct pinctrl_state *pinctrl_lookup_state(struct pinctrl *p, const char *name) -{ - struct pinctrl_state *s; - - mutex_lock(&pinctrl_mutex); - s = pinctrl_lookup_state_locked(p, name); - mutex_unlock(&pinctrl_mutex); - - return s; -} -EXPORT_SYMBOL_GPL(pinctrl_lookup_state); - -static int pinctrl_select_state_locked(struct pinctrl *p, - struct pinctrl_state *state) +int pinctrl_select_state(struct pinctrl *p, struct pinctrl_state *state) { struct pinctrl_setting *setting, *setting2; struct pinctrl_state *old_state = p->state; @@ -956,8 +986,9 @@ static int pinctrl_select_state_locked(struct pinctrl *p, break; } - if (ret < 0) + if (ret < 0) { goto unapply_new_state; + } } p->state = state; @@ -983,23 +1014,7 @@ unapply_new_state: /* There's no infinite recursive loop here because p->state is NULL */ if (old_state) - pinctrl_select_state_locked(p, old_state); - - return ret; -} - -/** - * pinctrl_select() - select/activate/program a pinctrl state to HW - * @p: the pinctrl handle for the device that requests configuratio - * @state: the state handle to select/activate/program - */ -int pinctrl_select_state(struct pinctrl *p, struct pinctrl_state *state) -{ - int ret; - - mutex_lock(&pinctrl_mutex); - ret = pinctrl_select_state_locked(p, state); - mutex_unlock(&pinctrl_mutex); + pinctrl_select_state(p, old_state); return ret; } @@ -1129,10 +1144,10 @@ int pinctrl_register_map(struct pinctrl_map const *maps, unsigned num_maps, } if (!locked) - mutex_lock(&pinctrl_mutex); + mutex_lock(&pinctrl_maps_mutex); list_add_tail(&maps_node->node, &pinctrl_maps); if (!locked) - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pinctrl_maps_mutex); return 0; } @@ -1154,12 +1169,15 @@ void pinctrl_unregister_map(struct pinctrl_map const *map) { struct pinctrl_maps *maps_node; + mutex_lock(&pinctrl_maps_mutex); list_for_each_entry(maps_node, &pinctrl_maps, node) { if (maps_node->maps == map) { list_del(&maps_node->node); + mutex_unlock(&pinctrl_maps_mutex); return; } } + mutex_unlock(&pinctrl_maps_mutex); } /** @@ -1196,7 +1214,7 @@ static int pinctrl_pins_show(struct seq_file *s, void *what) seq_printf(s, "registered pins: %d\n", pctldev->desc->npins); - mutex_lock(&pinctrl_mutex); + mutex_lock(&pctldev->mutex); /* The pin number can be retrived from the pin controller descriptor */ for (i = 0; i < pctldev->desc->npins; i++) { @@ -1218,7 +1236,7 @@ static int pinctrl_pins_show(struct seq_file *s, void *what) seq_puts(s, "\n"); } - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return 0; } @@ -1229,8 +1247,9 @@ static int pinctrl_groups_show(struct seq_file *s, void *what) const struct pinctrl_ops *ops = pctldev->desc->pctlops; unsigned ngroups, selector = 0; + mutex_lock(&pctldev->mutex); + ngroups = ops->get_groups_count(pctldev); - mutex_lock(&pinctrl_mutex); seq_puts(s, "registered pin groups:\n"); while (selector < ngroups) { @@ -1251,7 +1270,7 @@ static int pinctrl_groups_show(struct seq_file *s, void *what) for (i = 0; i < num_pins; i++) { pname = pin_get_name(pctldev, pins[i]); if (WARN_ON(!pname)) { - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return -EINVAL; } seq_printf(s, "pin %d (%s)\n", pins[i], pname); @@ -1261,7 +1280,7 @@ static int pinctrl_groups_show(struct seq_file *s, void *what) selector++; } - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return 0; } @@ -1273,7 +1292,7 @@ static int pinctrl_gpioranges_show(struct seq_file *s, void *what) seq_puts(s, "GPIO ranges handled:\n"); - mutex_lock(&pinctrl_mutex); + mutex_lock(&pctldev->mutex); /* Loop over the ranges */ list_for_each_entry(range, &pctldev->gpio_ranges, node) { @@ -1284,7 +1303,7 @@ static int pinctrl_gpioranges_show(struct seq_file *s, void *what) (range->pin_base + range->npins - 1)); } - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return 0; } @@ -1295,7 +1314,7 @@ static int pinctrl_devices_show(struct seq_file *s, void *what) seq_puts(s, "name [pinmux] [pinconf]\n"); - mutex_lock(&pinctrl_mutex); + mutex_lock(&pinctrldev_list_mutex); list_for_each_entry(pctldev, &pinctrldev_list, node) { seq_printf(s, "%s ", pctldev->desc->name); @@ -1310,7 +1329,7 @@ static int pinctrl_devices_show(struct seq_file *s, void *what) seq_puts(s, "\n"); } - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pinctrldev_list_mutex); return 0; } @@ -1339,8 +1358,7 @@ static int pinctrl_maps_show(struct seq_file *s, void *what) seq_puts(s, "Pinctrl maps:\n"); - mutex_lock(&pinctrl_mutex); - + mutex_lock(&pinctrl_maps_mutex); for_each_maps(maps_node, i, map) { seq_printf(s, "device %s\nstate %s\ntype %s (%d)\n", map->dev_name, map->name, map_type(map->type), @@ -1364,8 +1382,7 @@ static int pinctrl_maps_show(struct seq_file *s, void *what) seq_printf(s, "\n"); } - - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pinctrl_maps_mutex); return 0; } @@ -1378,7 +1395,7 @@ static int pinctrl_show(struct seq_file *s, void *what) seq_puts(s, "Requested pin control handlers their pinmux maps:\n"); - mutex_lock(&pinctrl_mutex); + mutex_lock(&pinctrl_list_mutex); list_for_each_entry(p, &pinctrl_list, node) { seq_printf(s, "device: %s current state: %s\n", @@ -1410,7 +1427,7 @@ static int pinctrl_show(struct seq_file *s, void *what) } } - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pinctrl_list_mutex); return 0; } @@ -1596,6 +1613,7 @@ struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc, INIT_RADIX_TREE(&pctldev->pin_desc_tree, GFP_KERNEL); INIT_LIST_HEAD(&pctldev->gpio_ranges); pctldev->dev = dev; + mutex_init(&pctldev->mutex); /* check core ops for sanity */ if (pinctrl_check_ops(pctldev)) { @@ -1625,38 +1643,37 @@ struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc, goto out_err; } - mutex_lock(&pinctrl_mutex); - + mutex_lock(&pinctrldev_list_mutex); list_add_tail(&pctldev->node, &pinctrldev_list); + mutex_unlock(&pinctrldev_list_mutex); + + pctldev->p = pinctrl_get(pctldev->dev); - pctldev->p = pinctrl_get_locked(pctldev->dev); if (!IS_ERR(pctldev->p)) { pctldev->hog_default = - pinctrl_lookup_state_locked(pctldev->p, - PINCTRL_STATE_DEFAULT); + pinctrl_lookup_state(pctldev->p, PINCTRL_STATE_DEFAULT); if (IS_ERR(pctldev->hog_default)) { dev_dbg(dev, "failed to lookup the default state\n"); } else { - if (pinctrl_select_state_locked(pctldev->p, + if (pinctrl_select_state(pctldev->p, pctldev->hog_default)) dev_err(dev, "failed to select default state\n"); } pctldev->hog_sleep = - pinctrl_lookup_state_locked(pctldev->p, + pinctrl_lookup_state(pctldev->p, PINCTRL_STATE_SLEEP); if (IS_ERR(pctldev->hog_sleep)) dev_dbg(dev, "failed to lookup the sleep state\n"); } - mutex_unlock(&pinctrl_mutex); - pinctrl_init_device_debugfs(pctldev); return pctldev; out_err: + mutex_destroy(&pctldev->mutex); kfree(pctldev); return NULL; } @@ -1674,12 +1691,13 @@ void pinctrl_unregister(struct pinctrl_dev *pctldev) if (pctldev == NULL) return; - pinctrl_remove_device_debugfs(pctldev); + mutex_lock(&pinctrldev_list_mutex); + mutex_lock(&pctldev->mutex); - mutex_lock(&pinctrl_mutex); + pinctrl_remove_device_debugfs(pctldev); if (!IS_ERR(pctldev->p)) - pinctrl_put_locked(pctldev->p, true); + pinctrl_put(pctldev->p); /* TODO: check that no pinmuxes are still active? */ list_del(&pctldev->node); @@ -1690,9 +1708,10 @@ void pinctrl_unregister(struct pinctrl_dev *pctldev) list_for_each_entry_safe(range, n, &pctldev->gpio_ranges, node) list_del(&range->node); + mutex_unlock(&pctldev->mutex); + mutex_destroy(&pctldev->mutex); kfree(pctldev); - - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pinctrldev_list_mutex); } EXPORT_SYMBOL_GPL(pinctrl_unregister); diff --git a/drivers/pinctrl/core.h b/drivers/pinctrl/core.h index 6d3d400..75476b3 100644 --- a/drivers/pinctrl/core.h +++ b/drivers/pinctrl/core.h @@ -33,6 +33,7 @@ struct pinctrl_gpio_range; * @p: result of pinctrl_get() for this device * @hog_default: default state for pins hogged by this device * @hog_sleep: sleep state for pins hogged by this device + * @mutex: mutex taken on each pin controller specific action * @device_root: debugfs root for this device */ struct pinctrl_dev { @@ -46,6 +47,7 @@ struct pinctrl_dev { struct pinctrl *p; struct pinctrl_state *hog_default; struct pinctrl_state *hog_sleep; + struct mutex mutex; #ifdef CONFIG_DEBUG_FS struct dentry *device_root; #endif @@ -168,6 +170,7 @@ struct pinctrl_maps { }; struct pinctrl_dev *get_pinctrl_dev_from_devname(const char *dev_name); +struct pinctrl_dev *get_pinctrl_dev_from_of_node(struct device_node *np); int pin_get_from_name(struct pinctrl_dev *pctldev, const char *name); const char *pin_get_name(struct pinctrl_dev *pctldev, const unsigned pin); int pinctrl_get_group_selector(struct pinctrl_dev *pctldev, @@ -186,8 +189,7 @@ void pinctrl_unregister_map(struct pinctrl_map const *map); extern int pinctrl_force_sleep(struct pinctrl_dev *pctldev); extern int pinctrl_force_default(struct pinctrl_dev *pctldev); -extern struct mutex pinctrl_mutex; -extern struct list_head pinctrldev_list; +extern struct mutex pinctrl_maps_mutex; extern struct list_head pinctrl_maps; #define for_each_maps(_maps_node_, _i_, _map_) \ diff --git a/drivers/pinctrl/devicetree.c b/drivers/pinctrl/devicetree.c index c7b7cb4..340fb4e 100644 --- a/drivers/pinctrl/devicetree.c +++ b/drivers/pinctrl/devicetree.c @@ -95,22 +95,11 @@ static int dt_remember_or_free_map(struct pinctrl *p, const char *statename, return pinctrl_register_map(map, num_maps, false, true); } -static struct pinctrl_dev *find_pinctrl_by_of_node(struct device_node *np) -{ - struct pinctrl_dev *pctldev; - - list_for_each_entry(pctldev, &pinctrldev_list, node) - if (pctldev->dev->of_node == np) - return pctldev; - - return NULL; -} - struct pinctrl_dev *of_pinctrl_get(struct device_node *np) { struct pinctrl_dev *pctldev; - pctldev = find_pinctrl_by_of_node(np); + pctldev = get_pinctrl_dev_from_of_node(np); if (!pctldev) return NULL; @@ -138,7 +127,7 @@ static int dt_to_map_one_config(struct pinctrl *p, const char *statename, /* OK let's just assume this will appear later then */ return -EPROBE_DEFER; } - pctldev = find_pinctrl_by_of_node(np_pctldev); + pctldev = get_pinctrl_dev_from_of_node(np_pctldev); if (pctldev) break; /* Do not defer probing of hogs (circular loop) */ diff --git a/drivers/pinctrl/pinconf.c b/drivers/pinctrl/pinconf.c index 32f9680..c67c37e 100644 --- a/drivers/pinctrl/pinconf.c +++ b/drivers/pinctrl/pinconf.c @@ -89,14 +89,14 @@ int pin_config_get(const char *dev_name, const char *name, struct pinctrl_dev *pctldev; int pin; - mutex_lock(&pinctrl_mutex); - pctldev = get_pinctrl_dev_from_devname(dev_name); if (!pctldev) { pin = -EINVAL; - goto unlock; + return pin; } + mutex_lock(&pctldev->mutex); + pin = pin_get_from_name(pctldev, name); if (pin < 0) goto unlock; @@ -104,7 +104,7 @@ int pin_config_get(const char *dev_name, const char *name, pin = pin_config_get_for_pin(pctldev, pin, config); unlock: - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return pin; } EXPORT_SYMBOL(pin_config_get); @@ -145,14 +145,14 @@ int pin_config_set(const char *dev_name, const char *name, struct pinctrl_dev *pctldev; int pin, ret; - mutex_lock(&pinctrl_mutex); - pctldev = get_pinctrl_dev_from_devname(dev_name); if (!pctldev) { ret = -EINVAL; - goto unlock; + return ret; } + mutex_lock(&pctldev->mutex); + pin = pin_get_from_name(pctldev, name); if (pin < 0) { ret = pin; @@ -162,7 +162,7 @@ int pin_config_set(const char *dev_name, const char *name, ret = pin_config_set_for_pin(pctldev, pin, config); unlock: - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return ret; } EXPORT_SYMBOL(pin_config_set); @@ -174,13 +174,14 @@ int pin_config_group_get(const char *dev_name, const char *pin_group, const struct pinconf_ops *ops; int selector, ret; - mutex_lock(&pinctrl_mutex); - pctldev = get_pinctrl_dev_from_devname(dev_name); if (!pctldev) { ret = -EINVAL; - goto unlock; + return ret; } + + mutex_lock(&pctldev->mutex); + ops = pctldev->desc->confops; if (!ops || !ops->pin_config_group_get) { @@ -200,7 +201,7 @@ int pin_config_group_get(const char *dev_name, const char *pin_group, ret = ops->pin_config_group_get(pctldev, selector, config); unlock: - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return ret; } EXPORT_SYMBOL(pin_config_group_get); @@ -217,13 +218,14 @@ int pin_config_group_set(const char *dev_name, const char *pin_group, int ret; int i; - mutex_lock(&pinctrl_mutex); - pctldev = get_pinctrl_dev_from_devname(dev_name); if (!pctldev) { ret = -EINVAL; - goto unlock; + return ret; } + + mutex_lock(&pctldev->mutex); + ops = pctldev->desc->confops; pctlops = pctldev->desc->pctlops; @@ -279,7 +281,7 @@ int pin_config_group_set(const char *dev_name, const char *pin_group, ret = 0; unlock: - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return ret; } @@ -487,7 +489,7 @@ static int pinconf_pins_show(struct seq_file *s, void *what) seq_puts(s, "Pin config settings per pin\n"); seq_puts(s, "Format: pin (name): configs\n"); - mutex_lock(&pinctrl_mutex); + mutex_lock(&pctldev->mutex); /* The pin number can be retrived from the pin controller descriptor */ for (i = 0; i < pctldev->desc->npins; i++) { @@ -507,7 +509,7 @@ static int pinconf_pins_show(struct seq_file *s, void *what) seq_printf(s, "\n"); } - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return 0; } @@ -608,7 +610,7 @@ static int pinconf_dbg_config_print(struct seq_file *s, void *d) bool found = false; unsigned long config; - mutex_lock(&pinctrl_mutex); + mutex_lock(&pctldev->mutex); /* Parse the pinctrl map and look for the elected pin/state */ for_each_maps(maps_node, i, map) { @@ -657,7 +659,7 @@ static int pinconf_dbg_config_print(struct seq_file *s, void *d) confops->pin_config_config_dbg_show(pctldev, s, config); exit: - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return 0; } @@ -747,7 +749,7 @@ static int pinconf_dbg_config_write(struct file *file, return -EINVAL; strncpy(config, token, MAX_NAME_LEN); - mutex_lock(&pinctrl_mutex); + mutex_lock(&pinctrl_maps_mutex); /* Parse the pinctrl map and look for the selected dev/state/pin */ for_each_maps(maps_node, i, map) { @@ -785,7 +787,7 @@ static int pinconf_dbg_config_write(struct file *file, } exit: - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pinctrl_maps_mutex); return count; } diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c index bd83c8b..88cc5095 100644 --- a/drivers/pinctrl/pinmux.c +++ b/drivers/pinctrl/pinmux.c @@ -506,7 +506,7 @@ static int pinmux_functions_show(struct seq_file *s, void *what) if (!pmxops) return 0; - mutex_lock(&pinctrl_mutex); + mutex_lock(&pctldev->mutex); nfuncs = pmxops->get_functions_count(pctldev); while (func_selector < nfuncs) { const char *func = pmxops->get_function_name(pctldev, @@ -530,7 +530,7 @@ static int pinmux_functions_show(struct seq_file *s, void *what) func_selector++; } - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return 0; } @@ -548,7 +548,7 @@ static int pinmux_pins_show(struct seq_file *s, void *what) seq_puts(s, "Pinmux settings per pin\n"); seq_puts(s, "Format: pin (name): mux_owner gpio_owner hog?\n"); - mutex_lock(&pinctrl_mutex); + mutex_lock(&pctldev->mutex); /* The pin number can be retrived from the pin controller descriptor */ for (i = 0; i < pctldev->desc->npins; i++) { @@ -583,7 +583,7 @@ static int pinmux_pins_show(struct seq_file *s, void *what) seq_printf(s, "\n"); } - mutex_unlock(&pinctrl_mutex); + mutex_unlock(&pctldev->mutex); return 0; } -- 2.7.4