Hi, On 02-09-17 21:13, sathya wrote:
Hi, On 09/01/2017 02:48 PM, Hans de Goede wrote:On non DT platforms we cannot get the mux_chip by pnode. Other subsystems (regulator, clock, pwm) have the same problem and solve this by allowing platform / board-setup code to add entries to a lookup table and then use this table to look things up. This commit adds support for getting a mux controller on a non DT platform following this pattern. It is based on a simplified version of the pwm subsys lookup code, the dev_id and mux_name parts of a lookup table entry are mandatory in the mux-core implementation. Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- drivers/mux/core.c | 96 +++++++++++++++++++++++++++++++++++++++++++- include/linux/mux/consumer.h | 11 +++++ 2 files changed, 106 insertions(+), 1 deletion(-) diff --git a/drivers/mux/core.c b/drivers/mux/core.c index 6142493c327b..8864cc745506 100644 --- a/drivers/mux/core.c +++ b/drivers/mux/core.c @@ -24,6 +24,9 @@ #include <linux/of_platform.h> #include <linux/slab.h> +static DEFINE_MUTEX(mux_lookup_lock); +static LIST_HEAD(mux_lookup_list); + /* * The idle-as-is "state" is not an actual state that may be selected, it * only implies that the state should not be changed. So, use that state @@ -408,6 +411,23 @@ int mux_control_deselect(struct mux_control *mux) } EXPORT_SYMBOL_GPL(mux_control_deselect); +static int parent_name_match(struct device *dev, const void *data) +{ + const char *parent_name = dev_name(dev->parent);Device name usually contains id section (devname.id). Did you take this into consideration ?+ const char *name = data; + + return strcmp(parent_name, name) == 0; +} + +static struct mux_chip *mux_chip_get_by_name(const char *name) +{ + struct device *dev; + + dev = class_find_device(&mux_class, NULL, name, parent_name_match); + + return dev ? to_mux_chip(dev) : NULL; +} + static int of_dev_node_match(struct device *dev, const void *data) { return dev->of_node == data; @@ -479,6 +499,42 @@ static struct mux_control *of_mux_control_get(struct device *dev, } /** + * mux_add_table() - register PWM device consumersPWM -> MUX
Thank you, good catch, fixed for v2. Regards, Hans
+ * @table: array of consumers to register + * @num: number of consumers in table + */ +void mux_add_table(struct mux_lookup *table, size_t num) +{ + mutex_lock(&mux_lookup_lock); + + while (num--) { + list_add_tail(&table->list, &mux_lookup_list); + table++; + } + + mutex_unlock(&mux_lookup_lock); +} +EXPORT_SYMBOL_GPL(mux_add_table); + +/** + * mux_remove_table() - unregister PWM device consumers + * @table: array of consumers to unregister + * @num: number of consumers in table + */ +void mux_remove_table(struct mux_lookup *table, size_t num) +{ + mutex_lock(&mux_lookup_lock); + + while (num--) { + list_del(&table->list); + table++; + } + + mutex_unlock(&mux_lookup_lock); +} +EXPORT_SYMBOL_GPL(mux_remove_table); + +/** * mux_control_get() - Get the mux-control for a device. * @dev: The device that needs a mux-control. * @mux_name: The name identifying the mux-control. @@ -487,11 +543,49 @@ static struct mux_control *of_mux_control_get(struct device *dev, */ struct mux_control *mux_control_get(struct device *dev, const char *mux_name) { + struct mux_lookup *m, *chosen = NULL; + const char *dev_id = dev_name(dev); + struct mux_chip *mux_chip; + /* look up via DT first */ if (IS_ENABLED(CONFIG_OF) && dev->of_node) return of_mux_control_get(dev, mux_name); - return ERR_PTR(-ENODEV); + /* + * For non DT we look up the provider in the static table typically + * provided by board setup code. + * + * If a match is found, the provider mux chip is looked up by name + * and a mux-control is requested using the table provided index. + */ + mutex_lock(&mux_lookup_lock); + list_for_each_entry(m, &mux_lookup_list, list) { + if (WARN_ON(!m->dev_id || !m->mux_name || !m->provider)) + continue; + + if (strcmp(m->dev_id, dev_id) == 0 && + strcmp(m->mux_name, mux_name) == 0) { + chosen = m; + break; + } + } + mutex_unlock(&mux_lookup_lock); + + if (!chosen) + return ERR_PTR(-ENODEV); + + mux_chip = mux_chip_get_by_name(chosen->provider); + if (!mux_chip) + return ERR_PTR(-EPROBE_DEFER); + + if (chosen->index >= mux_chip->controllers) { + dev_err(dev, "Mux lookup table index out of bounds %u >= %u\n", + chosen->index, mux_chip->controllers); + put_device(&mux_chip->dev); + return ERR_PTR(-EINVAL); + } + + return &mux_chip->mux[chosen->index]; } EXPORT_SYMBOL_GPL(mux_control_get); diff --git a/include/linux/mux/consumer.h b/include/linux/mux/consumer.h index ea96d4c82be7..912dd48a3a5d 100644 --- a/include/linux/mux/consumer.h +++ b/include/linux/mux/consumer.h @@ -18,6 +18,17 @@ struct device; struct mux_control; +struct mux_lookup { + struct list_head list; + const char *provider; + unsigned int index; + const char *dev_id; + const char *mux_name; +}; + +void mux_add_table(struct mux_lookup *table, size_t num); +void mux_remove_table(struct mux_lookup *table, size_t num); + unsigned int mux_control_states(struct mux_control *mux); int __must_check mux_control_select(struct mux_control *mux, unsigned int state);
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