diff options
Diffstat (limited to 'drivers/staging/iio/trigger/iio-trig-bfin-timer.c')
| -rw-r--r-- | drivers/staging/iio/trigger/iio-trig-bfin-timer.c | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/drivers/staging/iio/trigger/iio-trig-bfin-timer.c b/drivers/staging/iio/trigger/iio-trig-bfin-timer.c new file mode 100644 index 000000000000..583bef0936e8 --- /dev/null +++ b/drivers/staging/iio/trigger/iio-trig-bfin-timer.c @@ -0,0 +1,252 @@ +/* + * Copyright 2011 Analog Devices Inc. + * + * Licensed under the GPL-2. + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/delay.h> + +#include <asm/gptimers.h> + +#include "../iio.h" +#include "../trigger.h" + +struct bfin_timer { + unsigned short id, bit; + unsigned long irqbit; + int irq; +}; + +/* + * this covers all hardware timer configurations on + * all Blackfin derivatives out there today + */ + +static struct bfin_timer iio_bfin_timer_code[MAX_BLACKFIN_GPTIMERS] = { + {TIMER0_id, TIMER0bit, TIMER_STATUS_TIMIL0, IRQ_TIMER0}, + {TIMER1_id, TIMER1bit, TIMER_STATUS_TIMIL1, IRQ_TIMER1}, + {TIMER2_id, TIMER2bit, TIMER_STATUS_TIMIL2, IRQ_TIMER2}, +#if (MAX_BLACKFIN_GPTIMERS > 3) + {TIMER3_id, TIMER3bit, TIMER_STATUS_TIMIL3, IRQ_TIMER3}, + {TIMER4_id, TIMER4bit, TIMER_STATUS_TIMIL4, IRQ_TIMER4}, + {TIMER5_id, TIMER5bit, TIMER_STATUS_TIMIL5, IRQ_TIMER5}, + {TIMER6_id, TIMER6bit, TIMER_STATUS_TIMIL6, IRQ_TIMER6}, + {TIMER7_id, TIMER7bit, TIMER_STATUS_TIMIL7, IRQ_TIMER7}, +#endif +#if (MAX_BLACKFIN_GPTIMERS > 8) + {TIMER8_id, TIMER8bit, TIMER_STATUS_TIMIL8, IRQ_TIMER8}, + {TIMER9_id, TIMER9bit, TIMER_STATUS_TIMIL9, IRQ_TIMER9}, + {TIMER10_id, TIMER10bit, TIMER_STATUS_TIMIL10, IRQ_TIMER10}, +#if (MAX_BLACKFIN_GPTIMERS > 11) + {TIMER11_id, TIMER11bit, TIMER_STATUS_TIMIL11, IRQ_TIMER11}, +#endif +#endif +}; + +struct bfin_tmr_state { + struct iio_trigger *trig; + struct bfin_timer *t; + unsigned timer_num; + int irq; +}; + +static ssize_t iio_bfin_tmr_frequency_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + struct iio_trigger *trig = dev_get_drvdata(dev); + struct bfin_tmr_state *st = trig->private_data; + long val; + int ret; + + ret = strict_strtoul(buf, 10, &val); + if (ret) + goto error_ret; + + if (val > 100000) { + ret = -EINVAL; + goto error_ret; + } + + disable_gptimers(st->t->bit); + + if (!val) + goto error_ret; + + val = get_sclk() / val; + if (val <= 4) { + ret = -EINVAL; + goto error_ret; + } + + set_gptimer_period(st->t->id, val); + set_gptimer_pwidth(st->t->id, 1); + enable_gptimers(st->t->bit); + +error_ret: + return ret ? ret : count; +} + +static ssize_t iio_bfin_tmr_frequency_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_trigger *trig = dev_get_drvdata(dev); + struct bfin_tmr_state *st = trig->private_data; + + return sprintf(buf, "%lu\n", + get_sclk() / get_gptimer_period(st->t->id)); +} + +static DEVICE_ATTR(frequency, S_IRUGO | S_IWUSR, iio_bfin_tmr_frequency_show, + iio_bfin_tmr_frequency_store); +static IIO_TRIGGER_NAME_ATTR; + +static struct attribute *iio_bfin_tmr_trigger_attrs[] = { + &dev_attr_frequency.attr, + &dev_attr_name.attr, + NULL, +}; + +static const struct attribute_group iio_bfin_tmr_trigger_attr_group = { + .attrs = iio_bfin_tmr_trigger_attrs, +}; + + +static irqreturn_t iio_bfin_tmr_trigger_isr(int irq, void *devid) +{ + struct bfin_tmr_state *st = devid; + + clear_gptimer_intr(st->t->id); + iio_trigger_poll(st->trig, 0); + + return IRQ_HANDLED; +} + +static int iio_bfin_tmr_get_number(int irq) +{ + int i; + + for (i = 0; i < MAX_BLACKFIN_GPTIMERS; i++) + if (iio_bfin_timer_code[i].irq == irq) + return i; + + return -ENODEV; +} + +static int __devinit iio_bfin_tmr_trigger_probe(struct platform_device *pdev) +{ + struct bfin_tmr_state *st; + int ret; + + st = kzalloc(sizeof(*st), GFP_KERNEL); + if (st == NULL) { + ret = -ENOMEM; + goto out; + } + + st->irq = platform_get_irq(pdev, 0); + if (!st->irq) { + dev_err(&pdev->dev, "No IRQs specified"); + ret = -ENODEV; + goto out1; + } + + ret = iio_bfin_tmr_get_number(st->irq); + if (ret < 0) + goto out1; + + st->timer_num = ret; + st->t = &iio_bfin_timer_code[st->timer_num]; + + st->trig = iio_allocate_trigger(); + if (!st->trig) { + ret = -ENOMEM; + goto out1; + } + + st->trig->private_data = st; + st->trig->control_attrs = &iio_bfin_tmr_trigger_attr_group; + st->trig->owner = THIS_MODULE; + st->trig->name = kasprintf(GFP_KERNEL, "bfintmr%d", st->timer_num); + if (st->trig->name == NULL) { + ret = -ENOMEM; + goto out2; + } + + ret = iio_trigger_register(st->trig); + if (ret) + goto out3; + + ret = request_irq(st->irq, iio_bfin_tmr_trigger_isr, + 0, st->trig->name, st); + if (ret) { + dev_err(&pdev->dev, + "request IRQ-%d failed", st->irq); + goto out4; + } + + set_gptimer_config(st->t->id, OUT_DIS | PWM_OUT | PERIOD_CNT | IRQ_ENA); + + dev_info(&pdev->dev, "iio trigger Blackfin TMR%d, IRQ-%d", + st->timer_num, st->irq); + platform_set_drvdata(pdev, st); + + return 0; +out4: + iio_trigger_unregister(st->trig); +out3: + kfree(st->trig->name); +out2: + iio_put_trigger(st->trig); +out1: + kfree(st); +out: + return ret; +} + +static int __devexit iio_bfin_tmr_trigger_remove(struct platform_device *pdev) +{ + struct bfin_tmr_state *st = platform_get_drvdata(pdev); + + disable_gptimers(st->t->bit); + free_irq(st->irq, st); + iio_trigger_unregister(st->trig); + kfree(st->trig->name); + iio_put_trigger(st->trig); + kfree(st); + + return 0; +} + +static struct platform_driver iio_bfin_tmr_trigger_driver = { + .driver = { + .name = "iio_bfin_tmr_trigger", + .owner = THIS_MODULE, + }, + .probe = iio_bfin_tmr_trigger_probe, + .remove = __devexit_p(iio_bfin_tmr_trigger_remove), +}; + +static int __init iio_bfin_tmr_trig_init(void) +{ + return platform_driver_register(&iio_bfin_tmr_trigger_driver); +} +module_init(iio_bfin_tmr_trig_init); + +static void __exit iio_bfin_tmr_trig_exit(void) +{ + platform_driver_unregister(&iio_bfin_tmr_trigger_driver); +} +module_exit(iio_bfin_tmr_trig_exit); + +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); +MODULE_DESCRIPTION("Blackfin system timer based trigger for the iio subsystem"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:iio-trig-bfin-timer"); |