diff options
Diffstat (limited to 'drivers/counter/counter.c')
| -rw-r--r-- | drivers/counter/counter.c | 1567 |
1 files changed, 1567 insertions, 0 deletions
diff --git a/drivers/counter/counter.c b/drivers/counter/counter.c new file mode 100644 index 000000000000..106bc7180cd8 --- /dev/null +++ b/drivers/counter/counter.c @@ -0,0 +1,1567 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Generic Counter interface + * Copyright (C) 2018 William Breathitt Gray + */ +#include <linux/counter.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/export.h> +#include <linux/fs.h> +#include <linux/gfp.h> +#include <linux/idr.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/printk.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/sysfs.h> +#include <linux/types.h> + +const char *const counter_count_direction_str[2] = { + [COUNTER_COUNT_DIRECTION_FORWARD] = "forward", + [COUNTER_COUNT_DIRECTION_BACKWARD] = "backward" +}; +EXPORT_SYMBOL_GPL(counter_count_direction_str); + +const char *const counter_count_mode_str[4] = { + [COUNTER_COUNT_MODE_NORMAL] = "normal", + [COUNTER_COUNT_MODE_RANGE_LIMIT] = "range limit", + [COUNTER_COUNT_MODE_NON_RECYCLE] = "non-recycle", + [COUNTER_COUNT_MODE_MODULO_N] = "modulo-n" +}; +EXPORT_SYMBOL_GPL(counter_count_mode_str); + +ssize_t counter_signal_enum_read(struct counter_device *counter, + struct counter_signal *signal, void *priv, + char *buf) +{ + const struct counter_signal_enum_ext *const e = priv; + int err; + size_t index; + + if (!e->get) + return -EINVAL; + + err = e->get(counter, signal, &index); + if (err) + return err; + + if (index >= e->num_items) + return -EINVAL; + + return sprintf(buf, "%s\n", e->items[index]); +} +EXPORT_SYMBOL_GPL(counter_signal_enum_read); + +ssize_t counter_signal_enum_write(struct counter_device *counter, + struct counter_signal *signal, void *priv, + const char *buf, size_t len) +{ + const struct counter_signal_enum_ext *const e = priv; + ssize_t index; + int err; + + if (!e->set) + return -EINVAL; + + index = __sysfs_match_string(e->items, e->num_items, buf); + if (index < 0) + return index; + + err = e->set(counter, signal, index); + if (err) + return err; + + return len; +} +EXPORT_SYMBOL_GPL(counter_signal_enum_write); + +ssize_t counter_signal_enum_available_read(struct counter_device *counter, + struct counter_signal *signal, + void *priv, char *buf) +{ + const struct counter_signal_enum_ext *const e = priv; + size_t i; + size_t len = 0; + + if (!e->num_items) + return 0; + + for (i = 0; i < e->num_items; i++) + len += sprintf(buf + len, "%s\n", e->items[i]); + + return len; +} +EXPORT_SYMBOL_GPL(counter_signal_enum_available_read); + +ssize_t counter_count_enum_read(struct counter_device *counter, + struct counter_count *count, void *priv, + char *buf) +{ + const struct counter_count_enum_ext *const e = priv; + int err; + size_t index; + + if (!e->get) + return -EINVAL; + + err = e->get(counter, count, &index); + if (err) + return err; + + if (index >= e->num_items) + return -EINVAL; + + return sprintf(buf, "%s\n", e->items[index]); +} +EXPORT_SYMBOL_GPL(counter_count_enum_read); + +ssize_t counter_count_enum_write(struct counter_device *counter, + struct counter_count *count, void *priv, + const char *buf, size_t len) +{ + const struct counter_count_enum_ext *const e = priv; + ssize_t index; + int err; + + if (!e->set) + return -EINVAL; + + index = __sysfs_match_string(e->items, e->num_items, buf); + if (index < 0) + return index; + + err = e->set(counter, count, index); + if (err) + return err; + + return len; +} +EXPORT_SYMBOL_GPL(counter_count_enum_write); + +ssize_t counter_count_enum_available_read(struct counter_device *counter, + struct counter_count *count, + void *priv, char *buf) +{ + const struct counter_count_enum_ext *const e = priv; + size_t i; + size_t len = 0; + + if (!e->num_items) + return 0; + + for (i = 0; i < e->num_items; i++) + len += sprintf(buf + len, "%s\n", e->items[i]); + + return len; +} +EXPORT_SYMBOL_GPL(counter_count_enum_available_read); + +ssize_t counter_device_enum_read(struct counter_device *counter, void *priv, + char *buf) +{ + const struct counter_device_enum_ext *const e = priv; + int err; + size_t index; + + if (!e->get) + return -EINVAL; + + err = e->get(counter, &index); + if (err) + return err; + + if (index >= e->num_items) + return -EINVAL; + + return sprintf(buf, "%s\n", e->items[index]); +} +EXPORT_SYMBOL_GPL(counter_device_enum_read); + +ssize_t counter_device_enum_write(struct counter_device *counter, void *priv, + const char *buf, size_t len) +{ + const struct counter_device_enum_ext *const e = priv; + ssize_t index; + int err; + + if (!e->set) + return -EINVAL; + + index = __sysfs_match_string(e->items, e->num_items, buf); + if (index < 0) + return index; + + err = e->set(counter, index); + if (err) + return err; + + return len; +} +EXPORT_SYMBOL_GPL(counter_device_enum_write); + +ssize_t counter_device_enum_available_read(struct counter_device *counter, + void *priv, char *buf) +{ + const struct counter_device_enum_ext *const e = priv; + size_t i; + size_t len = 0; + + if (!e->num_items) + return 0; + + for (i = 0; i < e->num_items; i++) + len += sprintf(buf + len, "%s\n", e->items[i]); + + return len; +} +EXPORT_SYMBOL_GPL(counter_device_enum_available_read); + +static const char *const counter_signal_level_str[] = { + [COUNTER_SIGNAL_LEVEL_LOW] = "low", + [COUNTER_SIGNAL_LEVEL_HIGH] = "high" +}; + +/** + * counter_signal_read_value_set - set counter_signal_read_value data + * @val: counter_signal_read_value structure to set + * @type: property Signal data represents + * @data: Signal data + * + * This function sets an opaque counter_signal_read_value structure with the + * provided Signal data. + */ +void counter_signal_read_value_set(struct counter_signal_read_value *const val, + const enum counter_signal_value_type type, + void *const data) +{ + if (type == COUNTER_SIGNAL_LEVEL) + val->len = sprintf(val->buf, "%s\n", + counter_signal_level_str[*(enum counter_signal_level *)data]); + else + val->len = 0; +} +EXPORT_SYMBOL_GPL(counter_signal_read_value_set); + +/** + * counter_count_read_value_set - set counter_count_read_value data + * @val: counter_count_read_value structure to set + * @type: property Count data represents + * @data: Count data + * + * This function sets an opaque counter_count_read_value structure with the + * provided Count data. + */ +void counter_count_read_value_set(struct counter_count_read_value *const val, + const enum counter_count_value_type type, + void *const data) +{ + switch (type) { + case COUNTER_COUNT_POSITION: + val->len = sprintf(val->buf, "%lu\n", *(unsigned long *)data); + break; + default: + val->len = 0; + } +} +EXPORT_SYMBOL_GPL(counter_count_read_value_set); + +/** + * counter_count_write_value_get - get counter_count_write_value data + * @data: Count data + * @type: property Count data represents + * @val: counter_count_write_value structure containing data + * + * This function extracts Count data from the provided opaque + * counter_count_write_value structure and stores it at the address provided by + * @data. + * + * RETURNS: + * 0 on success, negative error number on failure. + */ +int counter_count_write_value_get(void *const data, + const enum counter_count_value_type type, + const struct counter_count_write_value *const val) +{ + int err; + + switch (type) { + case COUNTER_COUNT_POSITION: + err = kstrtoul(val->buf, 0, data); + if (err) + return err; + break; + } + + return 0; +} +EXPORT_SYMBOL_GPL(counter_count_write_value_get); + +struct counter_attr_parm { + struct counter_device_attr_group *group; + const char *prefix; + const char *name; + ssize_t (*show)(struct device *dev, struct device_attribute *attr, + char *buf); + ssize_t (*store)(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len); + void *component; +}; + +struct counter_device_attr { + struct device_attribute dev_attr; + struct list_head l; + void *component; +}; + +static int counter_attribute_create(const struct counter_attr_parm *const parm) +{ + struct counter_device_attr *counter_attr; + struct device_attribute *dev_attr; + int err; + struct list_head *const attr_list = &parm->group->attr_list; + + /* Allocate a Counter device attribute */ + counter_attr = kzalloc(sizeof(*counter_attr), GFP_KERNEL); + if (!counter_attr) + return -ENOMEM; + dev_attr = &counter_attr->dev_attr; + + sysfs_attr_init(&dev_attr->attr); + + /* Configure device attribute */ + dev_attr->attr.name = kasprintf(GFP_KERNEL, "%s%s", parm->prefix, + parm->name); + if (!dev_attr->attr.name) { + err = -ENOMEM; + goto err_free_counter_attr; + } + if (parm->show) { + dev_attr->attr.mode |= 0444; + dev_attr->show = parm->show; + } + if (parm->store) { + dev_attr->attr.mode |= 0200; + dev_attr->store = parm->store; + } + + /* Store associated Counter component with attribute */ + counter_attr->component = parm->component; + + /* Keep track of the attribute for later cleanup */ + list_add(&counter_attr->l, attr_list); + parm->group->num_attr++; + + return 0; + +err_free_counter_attr: + kfree(counter_attr); + return err; +} + +#define to_counter_attr(_dev_attr) \ + container_of(_dev_attr, struct counter_device_attr, dev_attr) + +struct counter_signal_unit { + struct counter_signal *signal; +}; + +static ssize_t counter_signal_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct counter_device *const counter = dev_get_drvdata(dev); + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_signal_unit *const component = devattr->component; + struct counter_signal *const signal = component->signal; + int err; + struct counter_signal_read_value val = { .buf = buf }; + + err = counter->ops->signal_read(counter, signal, &val); + if (err) + return err; + + return val.len; +} + +struct counter_name_unit { + const char *name; +}; + +static ssize_t counter_device_attr_name_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + const struct counter_name_unit *const comp = to_counter_attr(attr)->component; + + return sprintf(buf, "%s\n", comp->name); +} + +static int counter_name_attribute_create( + struct counter_device_attr_group *const group, + const char *const name) +{ + struct counter_name_unit *name_comp; + struct counter_attr_parm parm; + int err; + + /* Skip if no name */ + if (!name) + return 0; + + /* Allocate name attribute component */ + name_comp = kmalloc(sizeof(*name_comp), GFP_KERNEL); + if (!name_comp) + return -ENOMEM; + name_comp->name = name; + + /* Allocate Signal name attribute */ + parm.group = group; + parm.prefix = ""; + parm.name = "name"; + parm.show = counter_device_attr_name_show; + parm.store = NULL; + parm.component = name_comp; + err = counter_attribute_create(&parm); + if (err) + goto err_free_name_comp; + + return 0; + +err_free_name_comp: + kfree(name_comp); + return err; +} + +struct counter_signal_ext_unit { + struct counter_signal *signal; + const struct counter_signal_ext *ext; +}; + +static ssize_t counter_signal_ext_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_signal_ext_unit *const comp = devattr->component; + const struct counter_signal_ext *const ext = comp->ext; + + return ext->read(dev_get_drvdata(dev), comp->signal, ext->priv, buf); +} + +static ssize_t counter_signal_ext_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_signal_ext_unit *const comp = devattr->component; + const struct counter_signal_ext *const ext = comp->ext; + + return ext->write(dev_get_drvdata(dev), comp->signal, ext->priv, buf, + len); +} + +static void counter_device_attr_list_free(struct list_head *attr_list) +{ + struct counter_device_attr *p, *n; + + list_for_each_entry_safe(p, n, attr_list, l) { + /* free attribute name and associated component memory */ + kfree(p->dev_attr.attr.name); + kfree(p->component); + list_del(&p->l); + kfree(p); + } +} + +static int counter_signal_ext_register( + struct counter_device_attr_group *const group, + struct counter_signal *const signal) +{ + const size_t num_ext = signal->num_ext; + size_t i; + const struct counter_signal_ext *ext; + struct counter_signal_ext_unit *signal_ext_comp; + struct counter_attr_parm parm; + int err; + + /* Create an attribute for each extension */ + for (i = 0 ; i < num_ext; i++) { + ext = signal->ext + i; + + /* Allocate signal_ext attribute component */ + signal_ext_comp = kmalloc(sizeof(*signal_ext_comp), GFP_KERNEL); + if (!signal_ext_comp) { + err = -ENOMEM; + goto err_free_attr_list; + } + signal_ext_comp->signal = signal; + signal_ext_comp->ext = ext; + + /* Allocate a Counter device attribute */ + parm.group = group; + parm.prefix = ""; + parm.name = ext->name; + parm.show = (ext->read) ? counter_signal_ext_show : NULL; + parm.store = (ext->write) ? counter_signal_ext_store : NULL; + parm.component = signal_ext_comp; + err = counter_attribute_create(&parm); + if (err) { + kfree(signal_ext_comp); + goto err_free_attr_list; + } + } + + return 0; + +err_free_attr_list: + counter_device_attr_list_free(&group->attr_list); + return err; +} + +static int counter_signal_attributes_create( + struct counter_device_attr_group *const group, + const struct counter_device *const counter, + struct counter_signal *const signal) +{ + struct counter_signal_unit *signal_comp; + struct counter_attr_parm parm; + int err; + + /* Allocate Signal attribute component */ + signal_comp = kmalloc(sizeof(*signal_comp), GFP_KERNEL); + if (!signal_comp) + return -ENOMEM; + signal_comp->signal = signal; + + /* Create main Signal attribute */ + parm.group = group; + parm.prefix = ""; + parm.name = "signal"; + parm.show = (counter->ops->signal_read) ? counter_signal_show : NULL; + parm.store = NULL; + parm.component = signal_comp; + err = counter_attribute_create(&parm); + if (err) { + kfree(signal_comp); + return err; + } + + /* Create Signal name attribute */ + err = counter_name_attribute_create(group, signal->name); + if (err) + goto err_free_attr_list; + + /* Register Signal extension attributes */ + err = counter_signal_ext_register(group, signal); + if (err) + goto err_free_attr_list; + + return 0; + +err_free_attr_list: + counter_device_attr_list_free(&group->attr_list); + return err; +} + +static int counter_signals_register( + struct counter_device_attr_group *const groups_list, + const struct counter_device *const counter) +{ + const size_t num_signals = counter->num_signals; + size_t i; + struct counter_signal *signal; + const char *name; + int err; + + /* Register each Signal */ + for (i = 0; i < num_signals; i++) { + signal = counter->signals + i; + + /* Generate Signal attribute directory name */ + name = kasprintf(GFP_KERNEL, "signal%d", signal->id); + if (!name) { + err = -ENOMEM; + goto err_free_attr_groups; + } + groups_list[i].attr_group.name = name; + + /* Create all attributes associated with Signal */ + err = counter_signal_attributes_create(groups_list + i, counter, + signal); + if (err) + goto err_free_attr_groups; + } + + return 0; + +err_free_attr_groups: + do { + kfree(groups_list[i].attr_group.name); + counter_device_attr_list_free(&groups_list[i].attr_list); + } while (i--); + return err; +} + +static const char *const counter_synapse_action_str[] = { + [COUNTER_SYNAPSE_ACTION_NONE] = "none", + [COUNTER_SYNAPSE_ACTION_RISING_EDGE] = "rising edge", + [COUNTER_SYNAPSE_ACTION_FALLING_EDGE] = "falling edge", + [COUNTER_SYNAPSE_ACTION_BOTH_EDGES] = "both edges" +}; + +struct counter_action_unit { + struct counter_synapse *synapse; + struct counter_count *count; +}; + +static ssize_t counter_action_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + int err; + struct counter_device *const counter = dev_get_drvdata(dev); + const struct counter_action_unit *const component = devattr->component; + struct counter_count *const count = component->count; + struct counter_synapse *const synapse = component->synapse; + size_t action_index; + enum counter_synapse_action action; + + err = counter->ops->action_get(counter, count, synapse, &action_index); + if (err) + return err; + + synapse->action = action_index; + + action = synapse->actions_list[action_index]; + return sprintf(buf, "%s\n", counter_synapse_action_str[action]); +} + +static ssize_t counter_action_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_action_unit *const component = devattr->component; + struct counter_synapse *const synapse = component->synapse; + size_t action_index; + const size_t num_actions = synapse->num_actions; + enum counter_synapse_action action; + int err; + struct counter_device *const counter = dev_get_drvdata(dev); + struct counter_count *const count = component->count; + + /* Find requested action mode */ + for (action_index = 0; action_index < num_actions; action_index++) { + action = synapse->actions_list[action_index]; + if (sysfs_streq(buf, counter_synapse_action_str[action])) + break; + } + /* If requested action mode not found */ + if (action_index >= num_actions) + return -EINVAL; + + err = counter->ops->action_set(counter, count, synapse, action_index); + if (err) + return err; + + synapse->action = action_index; + + return len; +} + +struct counter_action_avail_unit { + const enum counter_synapse_action *actions_list; + size_t num_actions; +}; + +static ssize_t counter_synapse_action_available_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_action_avail_unit *const component = devattr->component; + size_t i; + enum counter_synapse_action action; + ssize_t len = 0; + + for (i = 0; i < component->num_actions; i++) { + action = component->actions_list[i]; + len += sprintf(buf + len, "%s\n", + counter_synapse_action_str[action]); + } + + return len; +} + +static int counter_synapses_register( + struct counter_device_attr_group *const group, + const struct counter_device *const counter, + struct counter_count *const count, const char *const count_attr_name) +{ + size_t i; + struct counter_synapse *synapse; + const char *prefix; + struct counter_action_unit *action_comp; + struct counter_attr_parm parm; + int err; + struct counter_action_avail_unit *avail_comp; + + /* Register each Synapse */ + for (i = 0; i < count->num_synapses; i++) { + synapse = count->synapses + i; + + /* Generate attribute prefix */ + prefix = kasprintf(GFP_KERNEL, "signal%d_", + synapse->signal->id); + if (!prefix) { + err = -ENOMEM; + goto err_free_attr_list; + } + + /* Allocate action attribute component */ + action_comp = kmalloc(sizeof(*action_comp), GFP_KERNEL); + if (!action_comp) { + err = -ENOMEM; + goto err_free_prefix; + } + action_comp->synapse = synapse; + action_comp->count = count; + + /* Create action attribute */ + parm.group = group; + parm.prefix = prefix; + parm.name = "action"; + parm.show = (counter->ops->action_get) ? counter_action_show : NULL; + parm.store = (counter->ops->action_set) ? counter_action_store : NULL; + parm.component = action_comp; + err = counter_attribute_create(&parm); + if (err) { + kfree(action_comp); + goto err_free_prefix; + } + + /* Allocate action available attribute component */ + avail_comp = kmalloc(sizeof(*avail_comp), GFP_KERNEL); + if (!avail_comp) { + err = -ENOMEM; + goto err_free_prefix; + } + avail_comp->actions_list = synapse->actions_list; + avail_comp->num_actions = synapse->num_actions; + + /* Create action_available attribute */ + parm.group = group; + parm.prefix = prefix; + parm.name = "action_available"; + parm.show = counter_synapse_action_available_show; + parm.store = NULL; + parm.component = avail_comp; + err = counter_attribute_create(&parm); + if (err) { + kfree(avail_comp); + goto err_free_prefix; + } + + kfree(prefix); + } + + return 0; + +err_free_prefix: + kfree(prefix); +err_free_attr_list: + counter_device_attr_list_free(&group->attr_list); + return err; +} + +struct counter_count_unit { + struct counter_count *count; +}; + +static ssize_t counter_count_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct counter_device *const counter = dev_get_drvdata(dev); + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_count_unit *const component = devattr->component; + struct counter_count *const count = component->count; + int err; + struct counter_count_read_value val = { .buf = buf }; + + err = counter->ops->count_read(counter, count, &val); + if (err) + return err; + + return val.len; +} + +static ssize_t counter_count_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct counter_device *const counter = dev_get_drvdata(dev); + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_count_unit *const component = devattr->component; + struct counter_count *const count = component->count; + int err; + struct counter_count_write_value val = { .buf = buf }; + + err = counter->ops->count_write(counter, count, &val); + if (err) + return err; + + return len; +} + +static const char *const counter_count_function_str[] = { + [COUNTER_COUNT_FUNCTION_INCREASE] = "increase", + [COUNTER_COUNT_FUNCTION_DECREASE] = "decrease", + [COUNTER_COUNT_FUNCTION_PULSE_DIRECTION] = "pulse-direction", + [COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A] = "quadrature x1 a", + [COUNTER_COUNT_FUNCTION_QUADRATURE_X1_B] = "quadrature x1 b", + [COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A] = "quadrature x2 a", + [COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B] = "quadrature x2 b", + [COUNTER_COUNT_FUNCTION_QUADRATURE_X4] = "quadrature x4" +}; + +static ssize_t counter_function_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int err; + struct counter_device *const counter = dev_get_drvdata(dev); + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_count_unit *const component = devattr->component; + struct counter_count *const count = component->count; + size_t func_index; + enum counter_count_function function; + + err = counter->ops->function_get(counter, count, &func_index); + if (err) + return err; + + count->function = func_index; + + function = count->functions_list[func_index]; + return sprintf(buf, "%s\n", counter_count_function_str[function]); +} + +static ssize_t counter_function_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_count_unit *const component = devattr->component; + struct counter_count *const count = component->count; + const size_t num_functions = count->num_functions; + size_t func_index; + enum counter_count_function function; + int err; + struct counter_device *const counter = dev_get_drvdata(dev); + + /* Find requested Count function mode */ + for (func_index = 0; func_index < num_functions; func_index++) { + function = count->functions_list[func_index]; + if (sysfs_streq(buf, counter_count_function_str[function])) + break; + } + /* Return error if requested Count function mode not found */ + if (func_index >= num_functions) + return -EINVAL; + + err = counter->ops->function_set(counter, count, func_index); + if (err) + return err; + + count->function = func_index; + + return len; +} + +struct counter_count_ext_unit { + struct counter_count *count; + const struct counter_count_ext *ext; +}; + +static ssize_t counter_count_ext_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_count_ext_unit *const comp = devattr->component; + const struct counter_count_ext *const ext = comp->ext; + + return ext->read(dev_get_drvdata(dev), comp->count, ext->priv, buf); +} + +static ssize_t counter_count_ext_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_count_ext_unit *const comp = devattr->component; + const struct counter_count_ext *const ext = comp->ext; + + return ext->write(dev_get_drvdata(dev), comp->count, ext->priv, buf, + len); +} + +static int counter_count_ext_register( + struct counter_device_attr_group *const group, + struct counter_count *const count) +{ + size_t i; + const struct counter_count_ext *ext; + struct counter_count_ext_unit *count_ext_comp; + struct counter_attr_parm parm; + int err; + + /* Create an attribute for each extension */ + for (i = 0 ; i < count->num_ext; i++) { + ext = count->ext + i; + + /* Allocate count_ext attribute component */ + count_ext_comp = kmalloc(sizeof(*count_ext_comp), GFP_KERNEL); + if (!count_ext_comp) { + err = -ENOMEM; + goto err_free_attr_list; + } + count_ext_comp->count = count; + count_ext_comp->ext = ext; + + /* Allocate count_ext attribute */ + parm.group = group; + parm.prefix = ""; + parm.name = ext->name; + parm.show = (ext->read) ? counter_count_ext_show : NULL; + parm.store = (ext->write) ? counter_count_ext_store : NULL; + parm.component = count_ext_comp; + err = counter_attribute_create(&parm); + if (err) { + kfree(count_ext_comp); + goto err_free_attr_list; + } + } + + return 0; + +err_free_attr_list: + counter_device_attr_list_free(&group->attr_list); + return err; +} + +struct counter_func_avail_unit { + const enum counter_count_function *functions_list; + size_t num_functions; +}; + +static ssize_t counter_count_function_available_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_func_avail_unit *const component = devattr->component; + const enum counter_count_function *const func_list = component->functions_list; + const size_t num_functions = component->num_functions; + size_t i; + enum counter_count_function function; + ssize_t len = 0; + + for (i = 0; i < num_functions; i++) { + function = func_list[i]; + len += sprintf(buf + len, "%s\n", + counter_count_function_str[function]); + } + + return len; +} + +static int counter_count_attributes_create( + struct counter_device_attr_group *const group, + const struct counter_device *const counter, + struct counter_count *const count) +{ + struct counter_count_unit *count_comp; + struct counter_attr_parm parm; + int err; + struct counter_count_unit *func_comp; + struct counter_func_avail_unit *avail_comp; + + /* Allocate count attribute component */ + count_comp = kmalloc(sizeof(*count_comp), GFP_KERNEL); + if (!count_comp) + return -ENOMEM; + count_comp->count = count; + + /* Create main Count attribute */ + parm.group = group; + parm.prefix = ""; + parm.name = "count"; + parm.show = (counter->ops->count_read) ? counter_count_show : NULL; + parm.store = (counter->ops->count_write) ? counter_count_store : NULL; + parm.component = count_comp; + err = counter_attribute_create(&parm); + if (err) { + kfree(count_comp); + return err; + } + + /* Allocate function attribute component */ + func_comp = kmalloc(sizeof(*func_comp), GFP_KERNEL); + if (!func_comp) { + err = -ENOMEM; + goto err_free_attr_list; + } + func_comp->count = count; + + /* Create Count function attribute */ + parm.group = group; + parm.prefix = ""; + parm.name = "function"; + parm.show = (counter->ops->function_get) ? counter_function_show : NULL; + parm.store = (counter->ops->function_set) ? counter_function_store : NULL; + parm.component = func_comp; + err = counter_attribute_create(&parm); + if (err) { + kfree(func_comp); + goto err_free_attr_list; + } + + /* Allocate function available attribute component */ + avail_comp = kmalloc(sizeof(*avail_comp), GFP_KERNEL); + if (!avail_comp) { + err = -ENOMEM; + goto err_free_attr_list; + } + avail_comp->functions_list = count->functions_list; + avail_comp->num_functions = count->num_functions; + + /* Create Count function_available attribute */ + parm.group = group; + parm.prefix = ""; + parm.name = "function_available"; + parm.show = counter_count_function_available_show; + parm.store = NULL; + parm.component = avail_comp; + err = counter_attribute_create(&parm); + if (err) { + kfree(avail_comp); + goto err_free_attr_list; + } + + /* Create Count name attribute */ + err = counter_name_attribute_create(group, count->name); + if (err) + goto err_free_attr_list; + + /* Register Count extension attributes */ + err = counter_count_ext_register(group, count); + if (err) + goto err_free_attr_list; + + return 0; + +err_free_attr_list: + counter_device_attr_list_free(&group->attr_list); + return err; +} + +static int counter_counts_register( + struct counter_device_attr_group *const groups_list, + const struct counter_device *const counter) +{ + size_t i; + struct counter_count *count; + const char *name; + int err; + + /* Register each Count */ + for (i = 0; i < counter->num_counts; i++) { + count = counter->counts + i; + + /* Generate Count attribute directory name */ + name = kasprintf(GFP_KERNEL, "count%d", count->id); + if (!name) { + err = -ENOMEM; + goto err_free_attr_groups; + } + groups_list[i].attr_group.name = name; + + /* Register the Synapses associated with each Count */ + err = counter_synapses_register(groups_list + i, counter, count, + name); + if (err) + goto err_free_attr_groups; + + /* Create all attributes associated with Count */ + err = counter_count_attributes_create(groups_list + i, counter, + count); + if (err) + goto err_free_attr_groups; + } + + return 0; + +err_free_attr_groups: + do { + kfree(groups_list[i].attr_group.name); + counter_device_attr_list_free(&groups_list[i].attr_list); + } while (i--); + return err; +} + +struct counter_size_unit { + size_t size; +}; + +static ssize_t counter_device_attr_size_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + const struct counter_size_unit *const comp = to_counter_attr(attr)->component; + + return sprintf(buf, "%zu\n", comp->size); +} + +static int counter_size_attribute_create( + struct counter_device_attr_group *const group, + const size_t size, const char *const name) +{ + struct counter_size_unit *size_comp; + struct counter_attr_parm parm; + int err; + + /* Allocate size attribute component */ + size_comp = kmalloc(sizeof(*size_comp), GFP_KERNEL); + if (!size_comp) + return -ENOMEM; + size_comp->size = size; + + parm.group = group; + parm.prefix = ""; + parm.name = name; + parm.show = counter_device_attr_size_show; + parm.store = NULL; + parm.component = size_comp; + err = counter_attribute_create(&parm); + if (err) + goto err_free_size_comp; + + return 0; + +err_free_size_comp: + kfree(size_comp); + return err; +} + +struct counter_ext_unit { + const struct counter_device_ext *ext; +}; + +static ssize_t counter_device_ext_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_ext_unit *const component = devattr->component; + const struct counter_device_ext *const ext = component->ext; + + return ext->read(dev_get_drvdata(dev), ext->priv, buf); +} + +static ssize_t counter_device_ext_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + const struct counter_device_attr *const devattr = to_counter_attr(attr); + const struct counter_ext_unit *const component = devattr->component; + const struct counter_device_ext *const ext = component->ext; + + return ext->write(dev_get_drvdata(dev), ext->priv, buf, len); +} + +static int counter_device_ext_register( + struct counter_device_attr_group *const group, + struct counter_device *const counter) +{ + size_t i; + struct counter_ext_unit *ext_comp; + struct counter_attr_parm parm; + int err; + + /* Create an attribute for each extension */ + for (i = 0 ; i < counter->num_ext; i++) { + /* Allocate extension attribute component */ + ext_comp = kmalloc(sizeof(*ext_comp), GFP_KERNEL); + if (!ext_comp) { + err = -ENOMEM; + goto err_free_attr_list; + } + + ext_comp->ext = counter->ext + i; + + /* Allocate extension attribute */ + parm.group = group; + parm.prefix = ""; + parm.name = counter->ext[i].name; + parm.show = (counter->ext[i].read) ? counter_device_ext_show : NULL; + parm.store = (counter->ext[i].write) ? counter_device_ext_store : NULL; + parm.component = ext_comp; + err = counter_attribute_create(&parm); + if (err) { + kfree(ext_comp); + goto err_free_attr_list; + } + } + + return 0; + +err_free_attr_list: + counter_device_attr_list_free(&group->attr_list); + return err; +} + +static int counter_global_attr_register( + struct counter_device_attr_group *const group, + struct counter_device *const counter) +{ + int err; + + /* Create name attribute */ + err = counter_name_attribute_create(group, counter->name); + if (err) + return err; + + /* Create num_counts attribute */ + err = counter_size_attribute_create(group, counter->num_counts, + "num_counts"); + if (err) + goto err_free_attr_list; + + /* Create num_signals attribute */ + err = counter_size_attribute_create(group, counter->num_signals, + "num_signals"); + if (err) + goto err_free_attr_list; + + /* Register Counter device extension attributes */ + err = counter_device_ext_register(group, counter); + if (err) + goto err_free_attr_list; + + return 0; + +err_free_attr_list: + counter_device_attr_list_free(&group->attr_list); + return err; +} + +static void counter_device_groups_list_free( + struct counter_device_attr_group *const groups_list, + const size_t num_groups) +{ + struct counter_device_attr_group *group; + size_t i; + + /* loop through all attribute groups (signals, counts, global, etc.) */ + for (i = 0; i < num_groups; i++) { + group = groups_list + i; + + /* free all attribute group and associated attributes memory */ + kfree(group->attr_group.name); + kfree(group->attr_group.attrs); + counter_device_attr_list_free(&group->attr_list); + } + + kfree(groups_list); +} + +static int counter_device_groups_list_prepare( + struct counter_device *const counter) +{ + const size_t total_num_groups = + counter->num_signals + counter->num_counts + 1; + struct counter_device_attr_group *groups_list; + size_t i; + int err; + size_t num_groups = 0; + + /* Allocate space for attribute groups (signals, counts, and ext) */ + groups_list = kcalloc(total_num_groups, sizeof(*groups_list), + GFP_KERNEL); + if (!groups_list) + return -ENOMEM; + + /* Initialize attribute lists */ + for (i = 0; i < total_num_groups; i++) + INIT_LIST_HEAD(&groups_list[i].attr_list); + + /* Register Signals */ + err = counter_signals_register(groups_list, counter); + if (err) + goto err_free_groups_list; + num_groups += counter->num_signals; + + /* Register Counts and respective Synapses */ + err = counter_counts_register(groups_list + num_groups, counter); + if (err) + goto err_free_groups_list; + num_groups += counter->num_counts; + + /* Register Counter global attributes */ + err = counter_global_attr_register(groups_list + num_groups, counter); + if (err) + goto err_free_groups_list; + num_groups++; + + /* Store groups_list in device_state */ + counter->device_state->groups_list = groups_list; + counter->device_state->num_groups = num_groups; + + return 0; + +err_free_groups_list: + counter_device_groups_list_free(groups_list, num_groups); + return err; +} + +static int counter_device_groups_prepare( + struct counter_device_state *const device_state) +{ + size_t i, j; + struct counter_device_attr_group *group; + int err; + struct counter_device_attr *p; + + /* Allocate attribute groups for association with device */ + device_state->groups = kcalloc(device_state->num_groups + 1, + sizeof(*device_state->groups), + GFP_KERNEL); + if (!device_state->groups) + return -ENOMEM; + + /* Prepare each group of attributes for association */ + for (i = 0; i < device_state->num_groups; i++) { + group = device_state->groups_list + i; + + /* Allocate space for attribute pointers in attribute group */ + group->attr_group.attrs = kcalloc(group->num_attr + 1, + sizeof(*group->attr_group.attrs), GFP_KERNEL); + if (!group->attr_group.attrs) { + err = -ENOMEM; + goto err_free_groups; + } + + /* Add attribute pointers to attribute group */ + j = 0; + list_for_each_entry(p, &group->attr_list, l) + group->attr_group.attrs[j++] = &p->dev_attr.attr; + + /* Group attributes in attribute group */ + device_state->groups[i] = &group->attr_group; + } + /* Associate attributes with device */ + device_state->dev.groups = device_state->groups; + + return 0; + +err_free_groups: + do { + group = device_state->groups_list + i; + kfree(group->attr_group.attrs); + group->attr_group.attrs = NULL; + } while (i--); + kfree(device_state->groups); + return err; +} + +/* Provides a unique ID for each counter device */ +static DEFINE_IDA(counter_ida); + +static void counter_device_release(struct device *dev) +{ + struct counter_device *const counter = dev_get_drvdata(dev); + struct counter_device_state *const device_state = counter->device_state; + + kfree(device_state->groups); + counter_device_groups_list_free(device_state->groups_list, + device_state->num_groups); + ida_simple_remove(&counter_ida, device_state->id); + kfree(device_state); +} + +static struct device_type counter_device_type = { + .name = "counter_device", + .release = counter_device_release +}; + +static struct bus_type counter_bus_type = { + .name = "counter" +}; + +/** + * counter_register - register Counter to the system + * @counter: pointer to Counter to register + * + * This function registers a Counter to the system. A sysfs "counter" directory + * will be created and populated with sysfs attributes correlating with the + * Counter Signals, Synapses, and Counts respectively. + */ +int counter_register(struct counter_device *const counter) +{ + struct counter_device_state *device_state; + int err; + + /* Allocate internal state container for Counter device */ + device_state = kzalloc(sizeof(*device_state), GFP_KERNEL); + if (!device_state) + return -ENOMEM; + counter->device_state = device_state; + + /* Acquire unique ID */ + device_state->id = ida_simple_get(&counter_ida, 0, 0, GFP_KERNEL); + if (device_state->id < 0) { + err = device_state->id; + goto err_free_device_state; + } + + /* Configure device structure for Counter */ + device_state->dev.type = &counter_device_type; + device_state->dev.bus = &counter_bus_type; + if (counter->parent) { + device_state->dev.parent = counter->parent; + device_state->dev.of_node = counter->parent->of_node; + } + dev_set_name(&device_state->dev, "counter%d", device_state->id); + device_initialize(&device_state->dev); + dev_set_drvdata(&device_state->dev, counter); + + /* Prepare device attributes */ + err = counter_device_groups_list_prepare(counter); + if (err) + goto err_free_id; + + /* Organize device attributes to groups and match to device */ + err = counter_device_groups_prepare(device_state); + if (err) + goto err_free_groups_list; + + /* Add device to system */ + err = device_add(&device_state->dev); + if (err) + goto err_free_groups; + + return 0; + +err_free_groups: + kfree(device_state->groups); +err_free_groups_list: + counter_device_groups_list_free(device_state->groups_list, + device_state->num_groups); +err_free_id: + ida_simple_remove(&counter_ida, device_state->id); +err_free_device_state: + kfree(device_state); + return err; +} +EXPORT_SYMBOL_GPL(counter_register); + +/** + * counter_unregister - unregister Counter from the system + * @counter: pointer to Counter to unregister + * + * The Counter is unregistered from the system; all allocated memory is freed. + */ +void counter_unregister(struct counter_device *const counter) +{ + if (counter) + device_del(&counter->device_state->dev); +} +EXPORT_SYMBOL_GPL(counter_unregister); + +static void devm_counter_unreg(struct device *dev, void *res) +{ + counter_unregister(*(struct counter_device **)res); +} + +/** + * devm_counter_register - Resource-managed counter_register + * @dev: device to allocate counter_device for + * @counter: pointer to Counter to register + * + * Managed counter_register. The Counter registered with this function is + * automatically unregistered on driver detach. This function calls + * counter_register internally. Refer to that function for more information. + * + * If an Counter registered with this function needs to be unregistered + * separately, devm_counter_unregister must be used. + * + * RETURNS: + * 0 on success, negative error number on failure. + */ +int devm_counter_register(struct device *dev, + struct counter_device *const counter) +{ + struct counter_device **ptr; + int ret; + + ptr = devres_alloc(devm_counter_unreg, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return -ENOMEM; + + ret = counter_register(counter); + if (!ret) { + *ptr = counter; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return ret; +} +EXPORT_SYMBOL_GPL(devm_counter_register); + +static int devm_counter_match(struct device *dev, void *res, void *data) +{ + struct counter_device **r = res; + + if (!r || !*r) { + WARN_ON(!r || !*r); + return 0; + } + + return *r == data; +} + +/** + * devm_counter_unregister - Resource-managed counter_unregister + * @dev: device this counter_device belongs to + * @counter: pointer to Counter associated with the device + * + * Unregister Counter registered with devm_counter_register. + */ +void devm_counter_unregister(struct device *dev, + struct counter_device *const counter) +{ + int rc; + + rc = devres_release(dev, devm_counter_unreg, devm_counter_match, + counter); + WARN_ON(rc); +} +EXPORT_SYMBOL_GPL(devm_counter_unregister); + +static int __init counter_init(void) +{ + return bus_register(&counter_bus_type); +} + +static void __exit counter_exit(void) +{ + bus_unregister(&counter_bus_type); +} + +subsys_initcall(counter_init); +module_exit(counter_exit); + +MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>"); +MODULE_DESCRIPTION("Generic Counter interface"); +MODULE_LICENSE("GPL v2"); |