diff options
author | nbd <nbd@3c298f89-4303-0410-b956-a3cf2f4a3e73> | 2010-06-26 20:42:58 +0000 |
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committer | nbd <nbd@3c298f89-4303-0410-b956-a3cf2f4a3e73> | 2010-06-26 20:42:58 +0000 |
commit | c5552ad03973839d83d32d7108f20c00f192633b (patch) | |
tree | de32e4def600e56134cd085a7447cb6620542078 /target/linux/generic-2.6/files/drivers/pwm/gpio.c | |
parent | 7ec88f88f4c65a22b3b7e32ef87cb42dcb32a6fb (diff) |
rename target/linux/generic-2.6 to generic
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@21952 3c298f89-4303-0410-b956-a3cf2f4a3e73
Diffstat (limited to 'target/linux/generic-2.6/files/drivers/pwm/gpio.c')
-rw-r--r-- | target/linux/generic-2.6/files/drivers/pwm/gpio.c | 298 |
1 files changed, 0 insertions, 298 deletions
diff --git a/target/linux/generic-2.6/files/drivers/pwm/gpio.c b/target/linux/generic-2.6/files/drivers/pwm/gpio.c deleted file mode 100644 index dff5d1d62..000000000 --- a/target/linux/generic-2.6/files/drivers/pwm/gpio.c +++ /dev/null @@ -1,298 +0,0 @@ -/* - * drivers/pwm/gpio.c - * - * Models a single-channel PWM device using a timer and a GPIO pin. - * - * 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/module.h> -#include <linux/init.h> -#include <linux/hrtimer.h> -#include <linux/err.h> -#include <linux/platform_device.h> -#include <linux/workqueue.h> -#include <linux/gpio.h> -#include <linux/slab.h> -#include <linux/pwm/pwm.h> - -struct gpio_pwm { - struct pwm_device pwm; - struct hrtimer timer; - struct work_struct work; - pwm_callback_t callback; - int gpio; - unsigned long polarity : 1; - unsigned long active : 1; -}; - -static inline struct gpio_pwm *to_gpio_pwm(const struct pwm_channel *p) -{ - return container_of(p->pwm, struct gpio_pwm, pwm); -} - -static void -gpio_pwm_work (struct work_struct *work) -{ - struct gpio_pwm *gp = container_of(work, struct gpio_pwm, work); - - if (gp->active) - gpio_direction_output(gp->gpio, gp->polarity ? 1 : 0); - else - gpio_direction_output(gp->gpio, gp->polarity ? 0 : 1); -} - -static enum hrtimer_restart -gpio_pwm_timeout(struct hrtimer *t) -{ - struct gpio_pwm *gp = container_of(t, struct gpio_pwm, timer); - ktime_t tnew; - - if (unlikely(gp->pwm.channels[0].duty_ticks == 0)) - gp->active = 0; - else if (unlikely(gp->pwm.channels[0].duty_ticks - == gp->pwm.channels[0].period_ticks)) - gp->active = 1; - else - gp->active ^= 1; - - if (gpio_cansleep(gp->gpio)) - schedule_work(&gp->work); - else - gpio_pwm_work(&gp->work); - - if (!gp->active && gp->pwm.channels[0].callback) - gp->pwm.channels[0].callback(&gp->pwm.channels[0]); - - if (unlikely(!gp->active && - (gp->pwm.channels[0].flags & BIT(FLAG_STOP)))) { - clear_bit(FLAG_STOP, &gp->pwm.channels[0].flags); - complete_all(&gp->pwm.channels[0].complete); - return HRTIMER_NORESTART; - } - - if (gp->active) - tnew = ktime_set(0, gp->pwm.channels[0].duty_ticks); - else - tnew = ktime_set(0, gp->pwm.channels[0].period_ticks - - gp->pwm.channels[0].duty_ticks); - hrtimer_start(&gp->timer, tnew, HRTIMER_MODE_REL); - - return HRTIMER_NORESTART; -} - -static void gpio_pwm_start(struct pwm_channel *p) -{ - struct gpio_pwm *gp = to_gpio_pwm(p); - - gp->active = 0; - gpio_pwm_timeout(&gp->timer); -} - -static int -gpio_pwm_config_nosleep(struct pwm_channel *p, - struct pwm_channel_config *c) -{ - struct gpio_pwm *gp = to_gpio_pwm(p); - int ret = 0; - unsigned long flags; - - spin_lock_irqsave(&p->lock, flags); - - switch (c->config_mask) { - - case PWM_CONFIG_DUTY_TICKS: - p->duty_ticks = c->duty_ticks; - break; - - case PWM_CONFIG_START: - if (!hrtimer_active(&gp->timer)) { - gpio_pwm_start(p); - } - break; - default: - ret = -EINVAL; - break; - } - - spin_unlock_irqrestore(&p->lock, flags); - return ret; -} - -static int -gpio_pwm_stop_sync(struct pwm_channel *p) -{ - struct gpio_pwm *gp = to_gpio_pwm(p); - int ret; - int was_on = hrtimer_active(&gp->timer); - - if (was_on) { - do { - init_completion(&p->complete); - set_bit(FLAG_STOP, &p->flags); - ret = wait_for_completion_interruptible(&p->complete); - if (ret) - return ret; - } while (p->flags & BIT(FLAG_STOP)); - } - - return was_on; -} - -static int -gpio_pwm_config(struct pwm_channel *p, - struct pwm_channel_config *c) -{ - struct gpio_pwm *gp = to_gpio_pwm(p); - int was_on = 0; - - if (p->pwm->config_nosleep) { - if (!p->pwm->config_nosleep(p, c)) - return 0; - } - - might_sleep(); - - was_on = gpio_pwm_stop_sync(p); - if (was_on < 0) - return was_on; - - if (c->config_mask & PWM_CONFIG_PERIOD_TICKS) - p->period_ticks = c->period_ticks; - - if (c->config_mask & PWM_CONFIG_DUTY_TICKS) - p->duty_ticks = c->duty_ticks; - - if (c->config_mask & PWM_CONFIG_POLARITY) { - gp->polarity = c->polarity ? 1 : 0; - p->active_high = gp->polarity; - } - - if ((c->config_mask & PWM_CONFIG_START) - || (was_on && !(c->config_mask & PWM_CONFIG_STOP))) - gpio_pwm_start(p); - - return 0; -} - -static int -gpio_pwm_set_callback(struct pwm_channel *p, - pwm_callback_t callback) -{ - struct gpio_pwm *gp = to_gpio_pwm(p); - gp->callback = callback; - return 0; -} - -static int -gpio_pwm_request(struct pwm_channel *p) -{ - p->tick_hz = 1000000000UL; - return 0; -} - -static int __devinit -gpio_pwm_probe(struct platform_device *pdev) -{ - struct gpio_pwm *gp; - struct gpio_pwm_platform_data *gpd = pdev->dev.platform_data; - int ret = 0; - - /* TODO: create configfs entries, so users can assign GPIOs to - * PWMs at runtime instead of creating a platform_device - * specification and rebuilding their kernel */ - - if (!gpd || gpio_request(gpd->gpio, dev_name(&pdev->dev))) - return -EINVAL; - - gp = kzalloc(sizeof(*gp), GFP_KERNEL); - if (!gp) { - ret = -ENOMEM; - goto err_alloc; - } - - platform_set_drvdata(pdev, gp); - - gp->pwm.dev = &pdev->dev; - gp->pwm.bus_id = dev_name(&pdev->dev); - gp->pwm.nchan = 1; - gp->gpio = gpd->gpio; - - INIT_WORK(&gp->work, gpio_pwm_work); - - hrtimer_init(&gp->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - gp->timer.function = gpio_pwm_timeout; - - gp->pwm.owner = THIS_MODULE; - gp->pwm.config_nosleep = gpio_pwm_config_nosleep; - gp->pwm.config = gpio_pwm_config; - gp->pwm.request = gpio_pwm_request; - gp->pwm.set_callback = gpio_pwm_set_callback; - - ret = pwm_register(&gp->pwm); - if (ret) - goto err_pwm_register; - - return 0; - -err_pwm_register: - platform_set_drvdata(pdev, 0); - kfree(gp); -err_alloc: - return ret; -} - -static int __devexit -gpio_pwm_remove(struct platform_device *pdev) -{ - struct gpio_pwm *gp = platform_get_drvdata(pdev); - int ret; - - ret = pwm_unregister(&gp->pwm); - hrtimer_cancel(&gp->timer); - cancel_work_sync(&gp->work); - platform_set_drvdata(pdev, 0); - kfree(gp); - - return 0; -} - -static struct platform_driver gpio_pwm_driver = { - .driver = { - .name = "gpio_pwm", - .owner = THIS_MODULE, - }, - .probe = gpio_pwm_probe, - .remove = __devexit_p(gpio_pwm_remove), -}; - -static int __init gpio_pwm_init(void) -{ - return platform_driver_register(&gpio_pwm_driver); -} -module_init(gpio_pwm_init); - -static void __exit gpio_pwm_exit(void) -{ - platform_driver_unregister(&gpio_pwm_driver); -} -module_exit(gpio_pwm_exit); - -MODULE_AUTHOR("Bill Gatliff <bgat@billgatliff.com>"); -MODULE_DESCRIPTION("PWM output using GPIO and a high-resolution timer"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS("platform:gpio_pwm"); |