pinctrl: API changes to support multiple states per device
The API model is changed from:
p = pinctrl_get(dev, "state1");
pinctrl_enable(p);
...
pinctrl_disable(p);
pinctrl_put(p);
p = pinctrl_get(dev, "state2");
pinctrl_enable(p);
...
pinctrl_disable(p);
pinctrl_put(p);
to this:
p = pinctrl_get(dev);
s1 = pinctrl_lookup_state(p, "state1");
s2 = pinctrl_lookup_state(p, "state2");
pinctrl_select_state(p, s1);
...
pinctrl_select_state(p, s2);
...
pinctrl_put(p);
This allows devices to directly transition between states without
disabling the pin controller programming and put()/get()ing the
configuration data each time. This model will also better suit pinconf
programming, which doesn't have a concept of "disable".
The special-case hogging feature of pin controllers is re-written to use
the regular APIs instead of special-case code. Hence, the pinmux-hogs
debugfs file is removed; see the top-level pinctrl-handles files for
equivalent data.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index 535f8d5..c6f3ca3 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -458,25 +458,98 @@
}
EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_output);
-static struct pinctrl *pinctrl_get_locked(struct device *dev, const char *name)
+static struct pinctrl_state *find_state(struct pinctrl *p,
+ const char *name)
{
- struct pinctrl_dev *pctldev;
- const char *devname;
- struct pinctrl *p;
- unsigned num_maps = 0;
+ struct pinctrl_state *state;
+
+ list_for_each_entry(state, &p->states, node)
+ if (!strcmp(state->name, name))
+ return state;
+
+ return NULL;
+}
+
+static struct pinctrl_state *create_state(struct pinctrl *p,
+ const char *name)
+{
+ struct pinctrl_state *state;
+
+ state = kzalloc(sizeof(*state), GFP_KERNEL);
+ if (state == NULL) {
+ dev_err(p->dev,
+ "failed to alloc struct pinctrl_state\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ state->name = name;
+ INIT_LIST_HEAD(&state->settings);
+
+ list_add_tail(&state->node, &p->states);
+
+ return state;
+}
+
+static int add_setting(struct pinctrl *p, struct pinctrl_map const *map)
+{
+ struct pinctrl_state *state;
+ struct pinctrl_setting *setting;
int ret;
+
+ state = find_state(p, map->name);
+ if (!state)
+ state = create_state(p, map->name);
+ if (IS_ERR(state))
+ return PTR_ERR(state);
+
+ setting = kzalloc(sizeof(*setting), GFP_KERNEL);
+ if (setting == NULL) {
+ dev_err(p->dev,
+ "failed to alloc struct pinctrl_setting\n");
+ return -ENOMEM;
+ }
+
+ setting->pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
+ if (setting->pctldev == NULL) {
+ dev_err(p->dev, "unknown pinctrl device %s in map entry",
+ map->ctrl_dev_name);
+ kfree(setting);
+ /* Eventually, this should trigger deferred probe */
+ return -ENODEV;
+ }
+
+ ret = pinmux_map_to_setting(map, setting);
+ if (ret < 0) {
+ kfree(setting);
+ return ret;
+ }
+
+ list_add_tail(&setting->node, &state->settings);
+
+ return 0;
+}
+
+static struct pinctrl *find_pinctrl(struct device *dev)
+{
+ struct pinctrl *p;
+
+ list_for_each_entry(p, &pinctrldev_list, node)
+ if (p->dev == dev)
+ return p;
+
+ return NULL;
+}
+
+static void pinctrl_put_locked(struct pinctrl *p, bool inlist);
+
+static struct pinctrl *create_pinctrl(struct device *dev)
+{
+ struct pinctrl *p;
+ const char *devname;
struct pinctrl_maps *maps_node;
int i;
struct pinctrl_map const *map;
- struct pinctrl_setting *setting;
-
- /* We must have both a dev and state name */
- if (WARN_ON(!dev || !name))
- return ERR_PTR(-EINVAL);
-
- devname = dev_name(dev);
-
- dev_dbg(dev, "pinctrl_get() for device %s state %s\n", devname, name);
+ int ret;
/*
* create the state cookie holder struct pinctrl for each
@@ -489,8 +562,9 @@
return ERR_PTR(-ENOMEM);
}
p->dev = dev;
- p->state = name;
- INIT_LIST_HEAD(&p->settings);
+ INIT_LIST_HEAD(&p->states);
+
+ devname = dev_name(dev);
/* Iterate over the pin control maps to locate the right ones */
for_each_maps(maps_node, i, map) {
@@ -498,139 +572,157 @@
if (strcmp(map->dev_name, devname))
continue;
- /* State name must be the one we're looking for */
- if (strcmp(map->name, name))
- continue;
-
- /*
- * Try to find the pctldev given in the map
- */
- pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
- if (!pctldev) {
- dev_err(dev, "unknown pinctrl device %s in map entry",
- map->ctrl_dev_name);
- /* Eventually, this should trigger deferred probe */
- ret = -ENODEV;
- goto error;
+ ret = add_setting(p, map);
+ if (ret < 0) {
+ pinctrl_put_locked(p, false);
+ return ERR_PTR(ret);
}
-
- dev_dbg(dev, "in map, found pctldev %s to handle function %s",
- dev_name(pctldev->dev), map->function);
-
- setting = kzalloc(sizeof(*setting), GFP_KERNEL);
- if (setting == NULL) {
- dev_err(dev,
- "failed to alloc struct pinctrl_setting\n");
- ret = -ENOMEM;
- goto error;
- }
-
- setting->pctldev = pctldev;
- ret = pinmux_map_to_setting(map, setting);
- if (ret < 0)
- goto error;
-
- list_add_tail(&setting->node, &p->settings);
-
- num_maps++;
}
- /*
- * This may be perfectly legitimate. An IP block may get re-used
- * across SoCs. Not all of those SoCs may need pinmux settings for the
- * IP block, e.g. if one SoC dedicates pins to that function but
- * another doesn't. The driver won't know this, and will always
- * attempt to set up the pinmux. The mapping table defines whether any
- * HW programming is actually needed.
- */
- if (!num_maps)
- dev_info(dev, "zero maps found for mapping %s\n", name);
-
- dev_dbg(dev, "found %u maps for device %s state %s\n",
- num_maps, devname, name ? name : "(undefined)");
-
/* Add the pinmux to the global list */
list_add_tail(&p->node, &pinctrl_list);
return p;
+}
-error:
- list_for_each_entry(setting, &p->settings, node)
- pinmux_free_setting(setting);
+static struct pinctrl *pinctrl_get_locked(struct device *dev)
+{
+ struct pinctrl *p;
- kfree(p);
+ if (WARN_ON(!dev))
+ return ERR_PTR(-EINVAL);
- return ERR_PTR(ret);
+ p = find_pinctrl(dev);
+ if (p != NULL)
+ return ERR_PTR(-EBUSY);
+
+ p = create_pinctrl(dev);
+ if (IS_ERR(p))
+ return p;
+
+ return p;
}
/**
- * pinctrl_get() - retrieves the pin controller handle for a certain device
- * @dev: the device to get the pin controller handle for
- * @name: an optional specific control mapping name or NULL, the name is only
- * needed if you want to have more than one mapping per device, or if you
- * need an anonymous pin control (not tied to any specific device)
+ * pinctrl_get() - retrieves the pinctrl handle for a device
+ * @dev: the device to obtain the handle for
*/
-struct pinctrl *pinctrl_get(struct device *dev, const char *name)
+struct pinctrl *pinctrl_get(struct device *dev)
{
struct pinctrl *p;
mutex_lock(&pinctrl_mutex);
- p = pinctrl_get_locked(dev, name);
+ p = pinctrl_get_locked(dev);
mutex_unlock(&pinctrl_mutex);
return p;
}
EXPORT_SYMBOL_GPL(pinctrl_get);
-static void pinctrl_put_locked(struct pinctrl *p)
+static void pinctrl_put_locked(struct pinctrl *p, bool inlist)
{
- struct pinctrl_setting *setting, *n;
+ struct pinctrl_state *state, *n1;
+ struct pinctrl_setting *setting, *n2;
- if (p == NULL)
- return;
-
- if (p->usecount)
- pr_warn("releasing pin control handle with active users!\n");
- list_for_each_entry_safe(setting, n, &p->settings, node) {
- pinmux_free_setting(setting);
- list_del(&setting->node);
- kfree(setting);
+ list_for_each_entry_safe(state, n1, &p->states, node) {
+ list_for_each_entry_safe(setting, n2, &state->settings, node) {
+ if (state == p->state)
+ pinmux_disable_setting(setting);
+ pinmux_free_setting(setting);
+ list_del(&setting->node);
+ kfree(setting);
+ }
+ list_del(&state->node);
+ kfree(state);
}
- /* Remove from list */
- list_del(&p->node);
-
+ if (inlist)
+ list_del(&p->node);
kfree(p);
}
/**
- * pinctrl_put() - release a previously claimed pin control handle
- * @p: a pin control handle previously claimed by pinctrl_get()
+ * pinctrl_put() - release a previously claimed pinctrl handle
+ * @p: the pinctrl handle to release
*/
void pinctrl_put(struct pinctrl *p)
{
mutex_lock(&pinctrl_mutex);
- pinctrl_put(p);
+ pinctrl_put_locked(p, true);
mutex_unlock(&pinctrl_mutex);
}
EXPORT_SYMBOL_GPL(pinctrl_put);
-static int pinctrl_enable_locked(struct pinctrl *p)
+static struct pinctrl_state *pinctrl_lookup_state_locked(struct pinctrl *p,
+ const char *name)
{
- struct pinctrl_setting *setting;
+ struct pinctrl_state *state;
+
+ state = find_state(p, name);
+ if (!state)
+ return ERR_PTR(-ENODEV);
+
+ return 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
+ */
+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)
+{
+ struct pinctrl_setting *setting, *setting2;
int ret;
- if (p == NULL)
- return -EINVAL;
+ if (p->state == state)
+ return 0;
- if (p->usecount++ == 0) {
- list_for_each_entry(setting, &p->settings, node) {
- ret = pinmux_enable_setting(setting);
- if (ret < 0) {
- /* FIXME: Difficult to return to prev state */
- p->usecount--;
- return ret;
+ if (p->state) {
+ /*
+ * The set of groups with a mux configuration in the old state
+ * may not be identical to the set of groups with a mux setting
+ * in the new state. While this might be unusual, it's entirely
+ * possible for the "user"-supplied mapping table to be written
+ * that way. For each group that was configured in the old state
+ * but not in the new state, this code puts that group into a
+ * safe/disabled state.
+ */
+ list_for_each_entry(setting, &p->state->settings, node) {
+ bool found = false;
+ list_for_each_entry(setting2, &state->settings, node) {
+ if (setting2->group_selector ==
+ setting->group_selector) {
+ found = true;
+ break;
+ }
}
+ if (!found)
+ pinmux_disable_setting(setting);
+ }
+ }
+
+ p->state = state;
+
+ /* Apply all the settings for the new state */
+ list_for_each_entry(setting, &state->settings, node) {
+ ret = pinmux_enable_setting(setting);
+ if (ret < 0) {
+ /* FIXME: Difficult to return to prev state */
+ return ret;
}
}
@@ -638,43 +730,21 @@
}
/**
- * pinctrl_enable() - enable a certain pin controller setting
- * @p: the pin control handle to enable, previously claimed by pinctrl_get()
+ * 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_enable(struct pinctrl *p)
+int pinctrl_select_state(struct pinctrl *p, struct pinctrl_state *state)
{
int ret;
+
mutex_lock(&pinctrl_mutex);
- ret = pinctrl_enable_locked(p);
+ ret = pinctrl_select_state_locked(p, state);
mutex_unlock(&pinctrl_mutex);
+
return ret;
}
-EXPORT_SYMBOL_GPL(pinctrl_enable);
-
-static void pinctrl_disable_locked(struct pinctrl *p)
-{
- struct pinctrl_setting *setting;
-
- if (p == NULL)
- return;
-
- if (--p->usecount == 0) {
- list_for_each_entry(setting, &p->settings, node)
- pinmux_disable_setting(setting);
- }
-}
-
-/**
- * pinctrl_disable() - disable a certain pin control setting
- * @p: the pin control handle to disable, previously claimed by pinctrl_get()
- */
-void pinctrl_disable(struct pinctrl *p)
-{
- mutex_lock(&pinctrl_mutex);
- pinctrl_disable_locked(p);
- mutex_unlock(&pinctrl_mutex);
-}
-EXPORT_SYMBOL_GPL(pinctrl_disable);
+EXPORT_SYMBOL_GPL(pinctrl_select_state);
/**
* pinctrl_register_mappings() - register a set of pin controller mappings
@@ -891,6 +961,7 @@
static int pinctrl_show(struct seq_file *s, void *what)
{
struct pinctrl *p;
+ struct pinctrl_state *state;
struct pinctrl_setting *setting;
seq_puts(s, "Requested pin control handlers their pinmux maps:\n");
@@ -898,12 +969,17 @@
mutex_lock(&pinctrl_mutex);
list_for_each_entry(p, &pinctrl_list, node) {
- seq_printf(s, "device: %s state: %s users: %u\n",
- dev_name(p->dev), p->state, p->usecount);
+ seq_printf(s, "device: %s current state: %s\n",
+ dev_name(p->dev),
+ p->state ? p->state->name : "none");
- list_for_each_entry(setting, &p->settings, node) {
- seq_printf(s, " ");
- pinmux_dbg_show(s, setting);
+ list_for_each_entry(state, &p->states, node) {
+ seq_printf(s, " state: %s\n", state->name);
+
+ list_for_each_entry(setting, &state->settings, node) {
+ seq_printf(s, " ");
+ pinmux_dbg_show(s, setting);
+ }
}
}
@@ -1113,9 +1189,14 @@
list_add_tail(&pctldev->node, &pinctrldev_list);
- pctldev->p = pinctrl_get_locked(pctldev->dev, PINCTRL_STATE_DEFAULT);
- if (!IS_ERR(pctldev->p))
- pinctrl_enable_locked(pctldev->p);
+ pctldev->p = pinctrl_get_locked(pctldev->dev);
+ if (!IS_ERR(pctldev->p)) {
+ struct pinctrl_state *s =
+ pinctrl_lookup_state_locked(pctldev->p,
+ PINCTRL_STATE_DEFAULT);
+ if (!IS_ERR(s))
+ pinctrl_select_state_locked(pctldev->p, s);
+ }
mutex_unlock(&pinctrl_mutex);
@@ -1144,10 +1225,8 @@
mutex_lock(&pinctrl_mutex);
- if (!IS_ERR(pctldev->p)) {
- pinctrl_disable_locked(pctldev->p);
- pinctrl_put_locked(pctldev->p);
- }
+ if (!IS_ERR(pctldev->p))
+ pinctrl_put_locked(pctldev->p, true);
/* TODO: check that no pinmuxes are still active? */
list_del(&pctldev->node);