diff options
Diffstat (limited to 'target/linux/generic/files/drivers/pwm/pwm.c')
| -rw-r--r-- | target/linux/generic/files/drivers/pwm/pwm.c | 643 |
1 files changed, 0 insertions, 643 deletions
diff --git a/target/linux/generic/files/drivers/pwm/pwm.c b/target/linux/generic/files/drivers/pwm/pwm.c deleted file mode 100644 index c1596e9e7e..0000000000 --- a/target/linux/generic/files/drivers/pwm/pwm.c +++ /dev/null @@ -1,643 +0,0 @@ -/* - * drivers/pwm/pwm.c - * - * Copyright (C) 2010 Bill Gatliff <bgat@billgatliff.com> - * - * This program is free software; you may redistribute and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 - * USA - */ - -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/init.h> -#include <linux/device.h> -#include <linux/spinlock.h> -#include <linux/fs.h> -#include <linux/completion.h> -#include <linux/workqueue.h> -#include <linux/list.h> -#include <linux/sched.h> -#include <linux/slab.h> /*kcalloc, kfree since 2.6.34 */ -#include <linux/pwm/pwm.h> - -static int __pwm_create_sysfs(struct pwm_device *pwm); - -static const char *REQUEST_SYSFS = "sysfs"; -static LIST_HEAD(pwm_device_list); -static DEFINE_MUTEX(device_list_mutex); -static struct class pwm_class; -static struct workqueue_struct *pwm_handler_workqueue; - -int pwm_register(struct pwm_device *pwm) -{ - struct pwm_channel *p; - int wchan; - int ret; - - spin_lock_init(&pwm->list_lock); - - p = kcalloc(pwm->nchan, sizeof(*p), GFP_KERNEL); - if (!p) - return -ENOMEM; - - for (wchan = 0; wchan < pwm->nchan; wchan++) { - spin_lock_init(&p[wchan].lock); - init_completion(&p[wchan].complete); - p[wchan].chan = wchan; - p[wchan].pwm = pwm; - } - - pwm->channels = p; - - mutex_lock(&device_list_mutex); - - list_add_tail(&pwm->list, &pwm_device_list); - ret = __pwm_create_sysfs(pwm); - if (ret) { - mutex_unlock(&device_list_mutex); - goto err_create_sysfs; - } - - mutex_unlock(&device_list_mutex); - - dev_info(pwm->dev, "%d channel%s\n", pwm->nchan, - pwm->nchan > 1 ? "s" : ""); - return 0; - -err_create_sysfs: - kfree(p); - - return ret; -} -EXPORT_SYMBOL(pwm_register); - -static int __match_device(struct device *dev, void *data) -{ - return dev_get_drvdata(dev) == data; -} - -int pwm_unregister(struct pwm_device *pwm) -{ - int wchan; - struct device *dev; - - mutex_lock(&device_list_mutex); - - for (wchan = 0; wchan < pwm->nchan; wchan++) { - if (pwm->channels[wchan].flags & BIT(FLAG_REQUESTED)) { - mutex_unlock(&device_list_mutex); - return -EBUSY; - } - } - - for (wchan = 0; wchan < pwm->nchan; wchan++) { - dev = class_find_device(&pwm_class, NULL, - &pwm->channels[wchan], - __match_device); - if (dev) { - put_device(dev); - device_unregister(dev); - } - } - - kfree(pwm->channels); - list_del(&pwm->list); - mutex_unlock(&device_list_mutex); - - return 0; -} -EXPORT_SYMBOL(pwm_unregister); - -static struct pwm_device * -__pwm_find_device(const char *bus_id) -{ - struct pwm_device *p; - - list_for_each_entry(p, &pwm_device_list, list) { - if (!strcmp(bus_id, p->bus_id)) - return p; - } - return NULL; -} - -static int -__pwm_request_channel(struct pwm_channel *p, - const char *requester) -{ - int ret; - - if (test_and_set_bit(FLAG_REQUESTED, &p->flags)) - return -EBUSY; - - if (p->pwm->request) { - ret = p->pwm->request(p); - if (ret) { - clear_bit(FLAG_REQUESTED, &p->flags); - return ret; - } - } - - p->requester = requester; - if (!strcmp(requester, REQUEST_SYSFS)) - p->pid = current->pid; - - return 0; -} - -struct pwm_channel * -pwm_request(const char *bus_id, - int chan, - const char *requester) -{ - struct pwm_device *p; - int ret; - - mutex_lock(&device_list_mutex); - - p = __pwm_find_device(bus_id); - if (!p || chan >= p->nchan) - goto err_no_device; - - if (!try_module_get(p->owner)) - goto err_module_get_failed; - - ret = __pwm_request_channel(&p->channels[chan], requester); - if (ret) - goto err_request_failed; - - mutex_unlock(&device_list_mutex); - return &p->channels[chan]; - -err_request_failed: - module_put(p->owner); -err_module_get_failed: -err_no_device: - mutex_unlock(&device_list_mutex); - return NULL; -} -EXPORT_SYMBOL(pwm_request); - -void pwm_free(struct pwm_channel *p) -{ - mutex_lock(&device_list_mutex); - - if (!test_and_clear_bit(FLAG_REQUESTED, &p->flags)) - goto done; - - pwm_stop(p); - pwm_unsynchronize(p, NULL); - pwm_set_handler(p, NULL, NULL); - - if (p->pwm->free) - p->pwm->free(p); - module_put(p->pwm->owner); -done: - mutex_unlock(&device_list_mutex); -} -EXPORT_SYMBOL(pwm_free); - -unsigned long pwm_ns_to_ticks(struct pwm_channel *p, - unsigned long nsecs) -{ - unsigned long long ticks; - - ticks = nsecs; - ticks *= p->tick_hz; - do_div(ticks, 1000000000); - return ticks; -} -EXPORT_SYMBOL(pwm_ns_to_ticks); - -unsigned long pwm_ticks_to_ns(struct pwm_channel *p, - unsigned long ticks) -{ - unsigned long long ns; - - if (!p->tick_hz) - return 0; - - ns = ticks; - ns *= 1000000000UL; - do_div(ns, p->tick_hz); - return ns; -} -EXPORT_SYMBOL(pwm_ticks_to_ns); - -static void -pwm_config_ns_to_ticks(struct pwm_channel *p, - struct pwm_channel_config *c) -{ - if (c->config_mask & PWM_CONFIG_PERIOD_NS) { - c->period_ticks = pwm_ns_to_ticks(p, c->period_ns); - c->config_mask &= ~PWM_CONFIG_PERIOD_NS; - c->config_mask |= PWM_CONFIG_PERIOD_TICKS; - } - - if (c->config_mask & PWM_CONFIG_DUTY_NS) { - c->duty_ticks = pwm_ns_to_ticks(p, c->duty_ns); - c->config_mask &= ~PWM_CONFIG_DUTY_NS; - c->config_mask |= PWM_CONFIG_DUTY_TICKS; - } -} - -static void -pwm_config_percent_to_ticks(struct pwm_channel *p, - struct pwm_channel_config *c) -{ - if (c->config_mask & PWM_CONFIG_DUTY_PERCENT) { - if (c->config_mask & PWM_CONFIG_PERIOD_TICKS) - c->duty_ticks = c->period_ticks; - else - c->duty_ticks = p->period_ticks; - - c->duty_ticks *= c->duty_percent; - c->duty_ticks /= 100; - c->config_mask &= ~PWM_CONFIG_DUTY_PERCENT; - c->config_mask |= PWM_CONFIG_DUTY_TICKS; - } -} - -int pwm_config_nosleep(struct pwm_channel *p, - struct pwm_channel_config *c) -{ - if (!p->pwm->config_nosleep) - return -EINVAL; - - pwm_config_ns_to_ticks(p, c); - pwm_config_percent_to_ticks(p, c); - - return p->pwm->config_nosleep(p, c); -} -EXPORT_SYMBOL(pwm_config_nosleep); - -int pwm_config(struct pwm_channel *p, - struct pwm_channel_config *c) -{ - int ret = 0; - - if (unlikely(!p->pwm->config)) - return -EINVAL; - - pwm_config_ns_to_ticks(p, c); - pwm_config_percent_to_ticks(p, c); - - switch (c->config_mask & (PWM_CONFIG_PERIOD_TICKS - | PWM_CONFIG_DUTY_TICKS)) { - case PWM_CONFIG_PERIOD_TICKS: - if (p->duty_ticks > c->period_ticks) { - ret = -EINVAL; - goto err; - } - break; - case PWM_CONFIG_DUTY_TICKS: - if (p->period_ticks < c->duty_ticks) { - ret = -EINVAL; - goto err; - } - break; - case PWM_CONFIG_DUTY_TICKS | PWM_CONFIG_PERIOD_TICKS: - if (c->duty_ticks > c->period_ticks) { - ret = -EINVAL; - goto err; - } - break; - default: - break; - } - -err: - dev_dbg(p->pwm->dev, "%s: config_mask %d period_ticks %lu duty_ticks %lu" - " polarity %d duty_ns %lu period_ns %lu duty_percent %d\n", - __func__, c->config_mask, c->period_ticks, c->duty_ticks, - c->polarity, c->duty_ns, c->period_ns, c->duty_percent); - - if (ret) - return ret; - return p->pwm->config(p, c); -} -EXPORT_SYMBOL(pwm_config); - -int pwm_set_period_ns(struct pwm_channel *p, - unsigned long period_ns) -{ - struct pwm_channel_config c = { - .config_mask = PWM_CONFIG_PERIOD_TICKS, - .period_ticks = pwm_ns_to_ticks(p, period_ns), - }; - - return pwm_config(p, &c); -} -EXPORT_SYMBOL(pwm_set_period_ns); - -unsigned long pwm_get_period_ns(struct pwm_channel *p) -{ - return pwm_ticks_to_ns(p, p->period_ticks); -} -EXPORT_SYMBOL(pwm_get_period_ns); - -int pwm_set_duty_ns(struct pwm_channel *p, - unsigned long duty_ns) -{ - struct pwm_channel_config c = { - .config_mask = PWM_CONFIG_DUTY_TICKS, - .duty_ticks = pwm_ns_to_ticks(p, duty_ns), - }; - return pwm_config(p, &c); -} -EXPORT_SYMBOL(pwm_set_duty_ns); - -unsigned long pwm_get_duty_ns(struct pwm_channel *p) -{ - return pwm_ticks_to_ns(p, p->duty_ticks); -} -EXPORT_SYMBOL(pwm_get_duty_ns); - -int pwm_set_duty_percent(struct pwm_channel *p, - int percent) -{ - struct pwm_channel_config c = { - .config_mask = PWM_CONFIG_DUTY_PERCENT, - .duty_percent = percent, - }; - return pwm_config(p, &c); -} -EXPORT_SYMBOL(pwm_set_duty_percent); - -int pwm_set_polarity(struct pwm_channel *p, - int active_high) -{ - struct pwm_channel_config c = { - .config_mask = PWM_CONFIG_POLARITY, - .polarity = active_high, - }; - return pwm_config(p, &c); -} -EXPORT_SYMBOL(pwm_set_polarity); - -int pwm_start(struct pwm_channel *p) -{ - struct pwm_channel_config c = { - .config_mask = PWM_CONFIG_START, - }; - return pwm_config(p, &c); -} -EXPORT_SYMBOL(pwm_start); - -int pwm_stop(struct pwm_channel *p) -{ - struct pwm_channel_config c = { - .config_mask = PWM_CONFIG_STOP, - }; - return pwm_config(p, &c); -} -EXPORT_SYMBOL(pwm_stop); - -int pwm_synchronize(struct pwm_channel *p, - struct pwm_channel *to_p) -{ - if (p->pwm != to_p->pwm) { - /* TODO: support cross-device synchronization */ - return -EINVAL; - } - - if (!p->pwm->synchronize) - return -EINVAL; - - return p->pwm->synchronize(p, to_p); -} -EXPORT_SYMBOL(pwm_synchronize); - -int pwm_unsynchronize(struct pwm_channel *p, - struct pwm_channel *from_p) -{ - if (from_p && (p->pwm != from_p->pwm)) { - /* TODO: support cross-device synchronization */ - return -EINVAL; - } - - if (!p->pwm->unsynchronize) - return -EINVAL; - - return p->pwm->unsynchronize(p, from_p); -} -EXPORT_SYMBOL(pwm_unsynchronize); - -static void pwm_handler(struct work_struct *w) -{ - struct pwm_channel *p = container_of(w, struct pwm_channel, - handler_work); - if (p->handler && p->handler(p, p->handler_data)) - pwm_stop(p); -} - -static void __pwm_callback(struct pwm_channel *p) -{ - queue_work(pwm_handler_workqueue, &p->handler_work); - dev_dbg(p->pwm->dev, "handler %p scheduled with data %p\n", - p->handler, p->handler_data); -} - -int pwm_set_handler(struct pwm_channel *p, - pwm_handler_t handler, - void *data) -{ - if (p->pwm->set_callback) { - p->handler_data = data; - p->handler = handler; - INIT_WORK(&p->handler_work, pwm_handler); - return p->pwm->set_callback(p, handler ? __pwm_callback : NULL); - } - return -EINVAL; -} -EXPORT_SYMBOL(pwm_set_handler); - -static ssize_t pwm_run_store(struct device *dev, - struct device_attribute *attr, - const char *buf, - size_t len) -{ - struct pwm_channel *p = dev_get_drvdata(dev); - if (sysfs_streq(buf, "1")) - pwm_start(p); - else if (sysfs_streq(buf, "0")) - pwm_stop(p); - return len; -} -static DEVICE_ATTR(run, 0200, NULL, pwm_run_store); - -static ssize_t pwm_duty_ns_show(struct device *dev, - struct device_attribute *attr, - char *buf) -{ - struct pwm_channel *p = dev_get_drvdata(dev); - return sprintf(buf, "%lu\n", pwm_get_duty_ns(p)); -} - -static ssize_t pwm_duty_ns_store(struct device *dev, - struct device_attribute *attr, - const char *buf, - size_t len) -{ - unsigned long duty_ns; - struct pwm_channel *p = dev_get_drvdata(dev); - - if (1 == sscanf(buf, "%lu", &duty_ns)) - pwm_set_duty_ns(p, duty_ns); - return len; -} -static DEVICE_ATTR(duty_ns, 0644, pwm_duty_ns_show, pwm_duty_ns_store); - -static ssize_t pwm_period_ns_show(struct device *dev, - struct device_attribute *attr, - char *buf) -{ - struct pwm_channel *p = dev_get_drvdata(dev); - return sprintf(buf, "%lu\n", pwm_get_period_ns(p)); -} - -static ssize_t pwm_period_ns_store(struct device *dev, - struct device_attribute *attr, - const char *buf, - size_t len) -{ - unsigned long period_ns; - struct pwm_channel *p = dev_get_drvdata(dev); - - if (1 == sscanf(buf, "%lu", &period_ns)) - pwm_set_period_ns(p, period_ns); - return len; -} -static DEVICE_ATTR(period_ns, 0644, pwm_period_ns_show, pwm_period_ns_store); - -static ssize_t pwm_polarity_show(struct device *dev, - struct device_attribute *attr, - char *buf) -{ - struct pwm_channel *p = dev_get_drvdata(dev); - return sprintf(buf, "%d\n", p->active_high ? 1 : 0); -} - -static ssize_t pwm_polarity_store(struct device *dev, - struct device_attribute *attr, - const char *buf, - size_t len) -{ - int polarity; - struct pwm_channel *p = dev_get_drvdata(dev); - - if (1 == sscanf(buf, "%d", &polarity)) - pwm_set_polarity(p, polarity); - return len; -} -static DEVICE_ATTR(polarity, 0644, pwm_polarity_show, pwm_polarity_store); - -static ssize_t pwm_request_show(struct device *dev, - struct device_attribute *attr, - char *buf) -{ - struct pwm_channel *p = dev_get_drvdata(dev); - mutex_lock(&device_list_mutex); - __pwm_request_channel(p, REQUEST_SYSFS); - mutex_unlock(&device_list_mutex); - - if (p->pid) - return sprintf(buf, "%s %d\n", p->requester, p->pid); - else - return sprintf(buf, "%s\n", p->requester); -} - -static ssize_t pwm_request_store(struct device *dev, - struct device_attribute *attr, - const char *buf, - size_t len) -{ - struct pwm_channel *p = dev_get_drvdata(dev); - pwm_free(p); - return len; -} -static DEVICE_ATTR(request, 0644, pwm_request_show, pwm_request_store); - -static const struct attribute *pwm_attrs[] = -{ - &dev_attr_run.attr, - &dev_attr_polarity.attr, - &dev_attr_duty_ns.attr, - &dev_attr_period_ns.attr, - &dev_attr_request.attr, - NULL, -}; - -static const struct attribute_group pwm_device_attr_group = { - .attrs = (struct attribute **)pwm_attrs, -}; - -static int __pwm_create_sysfs(struct pwm_device *pwm) -{ - int ret = 0; - struct device *dev; - int wchan; - - for (wchan = 0; wchan < pwm->nchan; wchan++) { - dev = device_create(&pwm_class, pwm->dev, MKDEV(0, 0), - pwm->channels + wchan, - "%s:%d", pwm->bus_id, wchan); - if (!dev) - goto err_dev_create; - ret = sysfs_create_group(&dev->kobj, &pwm_device_attr_group); - if (ret) - goto err_dev_create; - } - - return ret; - -err_dev_create: - for (wchan = 0; wchan < pwm->nchan; wchan++) { - dev = class_find_device(&pwm_class, NULL, - &pwm->channels[wchan], - __match_device); - if (dev) { - put_device(dev); - device_unregister(dev); - } - } - - return ret; -} - -static struct class_attribute pwm_class_attrs[] = { - __ATTR_NULL, -}; - -static struct class pwm_class = { - .name = "pwm", - .owner = THIS_MODULE, - - .class_attrs = pwm_class_attrs, -}; - -static int __init pwm_init(void) -{ - int ret; - - /* TODO: how to deal with devices that register very early? */ - pr_err("%s\n", __func__); - ret = class_register(&pwm_class); - if (ret < 0) - return ret; - - pwm_handler_workqueue = create_workqueue("pwmd"); - - return 0; -} -postcore_initcall(pwm_init); |