| Message ID | 1344593797-15819-2-git-send-email-timo.t.kokkonen@iki.fi (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
I should have probably tried this before, but when I enabled lock debugging with this driver, I got this: > [ 663.848083] BUG: sleeping function called from invalid context at kernel/mutex.c:269 > [ 663.856262] in_atomic(): 1, irqs_disabled(): 128, pid: 889, name: lircd > [ 663.863220] 1 lock held by lircd/889: > [ 663.867065] #0: (dm_timer_lock){......}, at: [<c00343e4>] omap_dm_timer_request_specific+0x18/0xc4 > [ 663.876739] irq event stamp: 1770 > [ 663.880218] hardirqs last enabled at (1769): [<c050e4fc>] __mutex_unlock_slowpath+0xe0/0x15c > [ 663.889221] hardirqs last disabled at (1770): [<c05102e8>] _raw_spin_lock_irqsave+0x1c/0x60 > [ 663.898010] softirqs last enabled at (1674): [<c04bcc14>] unix_create1+0x148/0x174 > [ 663.906066] softirqs last disabled at (1672): [<c04bcbfc>] unix_create1+0x130/0x174 > [ 663.914154] [<c0019a90>] (unwind_backtrace+0x0/0xf8) from [<c050e11c>] (mutex_lock_nested+0x28/0x328) > [ 663.923858] [<c050e11c>] (mutex_lock_nested+0x28/0x328) from [<c04196bc>] (clk_get_sys+0x1c/0xfc) > [ 663.933197] [<c04196bc>] (clk_get_sys+0x1c/0xfc) from [<c0034344>] (omap_dm_timer_prepare+0xe4/0x16c) > [ 663.942901] [<c0034344>] (omap_dm_timer_prepare+0xe4/0x16c) from [<c0034440>] (omap_dm_timer_request_specific+0x74/0xc4) > [ 663.954345] [<c0034440>] (omap_dm_timer_request_specific+0x74/0xc4) from [<c03e7554>] (lirc_rx51_open+0x50/0x154) > [ 663.965148] [<c03e7554>] (lirc_rx51_open+0x50/0x154) from [<c0103cf0>] (chrdev_open+0x98/0x16c) > [ 663.974304] [<c0103cf0>] (chrdev_open+0x98/0x16c) from [<c00fd608>] (do_dentry_open+0x1dc/0x264) > [ 663.983551] [<c00fd608>] (do_dentry_open+0x1dc/0x264) from [<c00fd9ec>] (finish_open+0x44/0x5c) > [ 663.992706] [<c00fd9ec>] (finish_open+0x44/0x5c) from [<c010e230>] (do_last.isra.21+0x598/0xba8) > [ 664.001953] [<c010e230>] (do_last.isra.21+0x598/0xba8) from [<c010e8e8>] (path_openat+0xa8/0x47c) > [ 664.011291] [<c010e8e8>] (path_openat+0xa8/0x47c) from [<c010efb4>] (do_filp_open+0x2c/0x80) > [ 664.020172] [<c010efb4>] (do_filp_open+0x2c/0x80) from [<c00fe674>] (do_sys_open+0xe0/0x174) > [ 664.029052] [<c00fe674>] (do_sys_open+0xe0/0x174) from [<c0013a60>] (ret_fast_syscall+0x0/0x3c) It appears that in omap_dm_timer_request() there is a call to spin_lock_irqsave() and then, as visible on the back trace, clk_get_sys() takes a mutex lock while the spinlock is still held. To me it appears commit 3392cdd33a0 might have introduced this problem, but I'm not sure. Any thoughts? -Timo -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Aug 10, 2012 at 01:16:36PM +0300, Timo Kokkonen wrote: > This is the driver for the IR transmitter diode found on the Nokia > N900 (also known as RX51) device. The driver is mostly the same as > found in the original 2.6.28 based kernel that comes with the device. > > The following modifications have been made compared to the original > driver version: > > - Adopt to the changes that has happen in the kernel during the past > five years, such as the change in the include paths > > - The OMAP DM-timers require much more care nowadays. The timers need > to be enabled and disabled or otherwise many actions fail. Timers > must not be freed without first stopping them or otherwise the timer > cannot be requested again. > > The code has been tested with sending IR codes with N900 device > running Debian userland. The device receiving the codes was Anysee > DVB-C USB receiver. > > Signed-off-by: Timo Kokkonen <timo.t.kokkonen@iki.fi> > --- > drivers/media/rc/Kconfig | 10 + > drivers/media/rc/Makefile | 1 + > drivers/media/rc/ir-rx51.c | 496 ++++++++++++++++++++++++++++++++++++++++++++ > include/media/ir-rx51.h | 10 + > 4 files changed, 517 insertions(+), 0 deletions(-) > create mode 100644 drivers/media/rc/ir-rx51.c > create mode 100644 include/media/ir-rx51.h > > diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig > index 5180390..ab35d2e 100644 > --- a/drivers/media/rc/Kconfig > +++ b/drivers/media/rc/Kconfig > @@ -270,6 +270,16 @@ config IR_IGUANA > To compile this driver as a module, choose M here: the module will > be called iguanair. > > +config IR_RX51 > + tristate "Nokia N900 IR transmitter diode > + depends on MACH_NOKIA_RX51 && OMAP_DM_TIMER > + ---help--- > + Say Y or M here if you want to enable support for the IR > + transmitter diode built in the Nokia N900 (RX51) device. > + > + The driver uses omap DM timers for gereating the carrier > + wave and pulses. > + > config RC_LOOPBACK > tristate "Remote Control Loopback Driver" > depends on RC_CORE > diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile > index f871d19..d384f30 100644 > --- a/drivers/media/rc/Makefile > +++ b/drivers/media/rc/Makefile > @@ -23,6 +23,7 @@ obj-$(CONFIG_IR_FINTEK) += fintek-cir.o > obj-$(CONFIG_IR_NUVOTON) += nuvoton-cir.o > obj-$(CONFIG_IR_ENE) += ene_ir.o > obj-$(CONFIG_IR_REDRAT3) += redrat3.o > +obj-$(CONFIG_IR_RX51) += ir-rx51.o > obj-$(CONFIG_IR_STREAMZAP) += streamzap.o > obj-$(CONFIG_IR_WINBOND_CIR) += winbond-cir.o > obj-$(CONFIG_RC_LOOPBACK) += rc-loopback.o > diff --git a/drivers/media/rc/ir-rx51.c b/drivers/media/rc/ir-rx51.c > new file mode 100644 > index 0000000..9487dd3 > --- /dev/null > +++ b/drivers/media/rc/ir-rx51.c > @@ -0,0 +1,496 @@ > +/* > + * Copyright (C) 2008 Nokia Corporation > + * > + * Based on lirc_serial.c > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * 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/interrupt.h> > +#include <linux/uaccess.h> > +#include <linux/platform_device.h> > +#include <linux/sched.h> > +#include <linux/wait.h> > + > +#include <plat/dmtimer.h> > +#include <plat/clock.h> > +#include <plat/omap-pm.h> > + > +#include <media/lirc.h> > +#include <media/lirc_dev.h> > +#include <media/ir-rx51.h> > + > +#define LIRC_RX51_DRIVER_FEATURES (LIRC_CAN_SET_SEND_DUTY_CYCLE | \ > + LIRC_CAN_SET_SEND_CARRIER | \ > + LIRC_CAN_SEND_PULSE) > + > +#define DRIVER_NAME "lirc_rx51" > + > +#define WBUF_LEN 256 > + > +#define TIMER_MAX_VALUE 0xffffffff > + > +struct lirc_rx51 { > + struct omap_dm_timer *pwm_timer; > + struct omap_dm_timer *pulse_timer; > + struct device *dev; > + struct lirc_rx51_platform_data *pdata; > + wait_queue_head_t wqueue; > + > + unsigned long fclk_khz; > + unsigned int freq; /* carrier frequency */ > + unsigned int duty_cycle; /* carrier duty cycle */ > + unsigned int irq_num; > + unsigned int match; > + int wbuf[WBUF_LEN]; > + int wbuf_index; > + unsigned long device_is_open; > + unsigned int pwm_timer_num; > +}; > + > +static void lirc_rx51_on(struct lirc_rx51 *lirc_rx51) > +{ > + omap_dm_timer_set_pwm(lirc_rx51->pwm_timer, 0, 1, > + OMAP_TIMER_TRIGGER_OVERFLOW_AND_COMPARE); > +} > + > +static void lirc_rx51_off(struct lirc_rx51 *lirc_rx51) > +{ > + omap_dm_timer_set_pwm(lirc_rx51->pwm_timer, 0, 1, > + OMAP_TIMER_TRIGGER_NONE); > +} > + > +static int init_timing_params(struct lirc_rx51 *lirc_rx51) > +{ > + u32 load, match; > + > + load = -(lirc_rx51->fclk_khz * 1000 / lirc_rx51->freq); > + match = -(lirc_rx51->duty_cycle * -load / 100); > + omap_dm_timer_set_load(lirc_rx51->pwm_timer, 1, load); > + omap_dm_timer_set_match(lirc_rx51->pwm_timer, 1, match); > + omap_dm_timer_write_counter(lirc_rx51->pwm_timer, TIMER_MAX_VALUE - 2); > + omap_dm_timer_start(lirc_rx51->pwm_timer); > + omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, 0); > + omap_dm_timer_start(lirc_rx51->pulse_timer); > + > + lirc_rx51->match = 0; > + > + return 0; > +} > + > +#define tics_after(a, b) ((long)(b) - (long)(a) < 0) > + > +static int pulse_timer_set_timeout(struct lirc_rx51 *lirc_rx51, int usec) > +{ > + int counter; > + > + BUG_ON(usec < 0); > + > + if (lirc_rx51->match == 0) > + counter = omap_dm_timer_read_counter(lirc_rx51->pulse_timer); > + else > + counter = lirc_rx51->match; > + > + counter += (u32)(lirc_rx51->fclk_khz * usec / (1000)); > + omap_dm_timer_set_match(lirc_rx51->pulse_timer, 1, counter); > + omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, > + OMAP_TIMER_INT_MATCH); > + if (tics_after(omap_dm_timer_read_counter(lirc_rx51->pulse_timer), > + counter)) { > + return 1; > + } > + return 0; > +} > + > +static irqreturn_t lirc_rx51_interrupt_handler(int irq, void *ptr) > +{ > + unsigned int retval; > + struct lirc_rx51 *lirc_rx51 = ptr; > + > + retval = omap_dm_timer_read_status(lirc_rx51->pulse_timer); > + if (!retval) > + return IRQ_NONE; > + > + if ((retval & ~OMAP_TIMER_INT_MATCH)) > + dev_err_ratelimited(lirc_rx51->dev, > + ": Unexpected interrupt source: %x\n", retval); > + > + omap_dm_timer_write_status(lirc_rx51->pulse_timer, 7); > + if (lirc_rx51->wbuf_index < 0) { > + dev_err_ratelimited(lirc_rx51->dev, > + ": BUG wbuf_index has value of %i\n", > + lirc_rx51->wbuf_index); > + goto end; > + } > + > + /* > + * If we happen to hit an odd latency spike, loop through the > + * pulses until we catch up. > + */ > + do { > + if (lirc_rx51->wbuf_index >= WBUF_LEN) > + goto end; > + if (lirc_rx51->wbuf[lirc_rx51->wbuf_index] == -1) > + goto end; > + > + if (lirc_rx51->wbuf_index % 2) > + lirc_rx51_off(lirc_rx51); > + else > + lirc_rx51_on(lirc_rx51); > + > + retval = pulse_timer_set_timeout(lirc_rx51, > + lirc_rx51->wbuf[lirc_rx51->wbuf_index]); > + lirc_rx51->wbuf_index++; > + > + } while (retval); > + > + return IRQ_HANDLED; > +end: > + /* Stop TX here */ > + lirc_rx51_off(lirc_rx51); > + lirc_rx51->wbuf_index = -1; > + omap_dm_timer_stop(lirc_rx51->pwm_timer); > + omap_dm_timer_stop(lirc_rx51->pulse_timer); > + omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, 0); > + wake_up_interruptible(&lirc_rx51->wqueue); > + > + return IRQ_HANDLED; > +} > + > +static int lirc_rx51_init_port(struct lirc_rx51 *lirc_rx51) > +{ > + struct clk *clk_fclk; > + int retval, pwm_timer = lirc_rx51->pwm_timer_num; > + > + lirc_rx51->pwm_timer = omap_dm_timer_request_specific(pwm_timer); > + if (lirc_rx51->pwm_timer == NULL) { > + dev_err(lirc_rx51->dev, ": Error requesting GPT%d timer\n", > + pwm_timer); > + return -EBUSY; > + } > + > + lirc_rx51->pulse_timer = omap_dm_timer_request(); > + if (lirc_rx51->pulse_timer == NULL) { > + dev_err(lirc_rx51->dev, ": Error requesting pulse timer\n"); > + retval = -EBUSY; > + goto err1; > + } > + > + omap_dm_timer_set_source(lirc_rx51->pwm_timer, OMAP_TIMER_SRC_SYS_CLK); > + omap_dm_timer_set_source(lirc_rx51->pulse_timer, > + OMAP_TIMER_SRC_SYS_CLK); > + > + omap_dm_timer_enable(lirc_rx51->pwm_timer); > + omap_dm_timer_enable(lirc_rx51->pulse_timer); > + > + lirc_rx51->irq_num = omap_dm_timer_get_irq(lirc_rx51->pulse_timer); > + retval = request_irq(lirc_rx51->irq_num, lirc_rx51_interrupt_handler, > + IRQF_DISABLED | IRQF_SHARED, > + "lirc_pulse_timer", lirc_rx51); > + if (retval) { > + dev_err(lirc_rx51->dev, ": Failed to request interrupt line\n"); > + goto err2; > + } > + > + clk_fclk = omap_dm_timer_get_fclk(lirc_rx51->pwm_timer); > + lirc_rx51->fclk_khz = clk_fclk->rate / 1000; > + > + return 0; > + > +err2: > + omap_dm_timer_free(lirc_rx51->pulse_timer); > +err1: > + omap_dm_timer_free(lirc_rx51->pwm_timer); > + > + return retval; > +} > + > +static int lirc_rx51_free_port(struct lirc_rx51 *lirc_rx51) > +{ > + omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, 0); > + free_irq(lirc_rx51->irq_num, lirc_rx51); > + lirc_rx51_off(lirc_rx51); > + omap_dm_timer_disable(lirc_rx51->pwm_timer); > + omap_dm_timer_disable(lirc_rx51->pulse_timer); > + omap_dm_timer_free(lirc_rx51->pwm_timer); > + omap_dm_timer_free(lirc_rx51->pulse_timer); > + lirc_rx51->wbuf_index = -1; > + > + return 0; > +} > + > +static ssize_t lirc_rx51_write(struct file *file, const char *buf, > + size_t n, loff_t *ppos) > +{ > + int count, i; > + struct lirc_rx51 *lirc_rx51 = file->private_data; > + > + if (n % sizeof(int)) > + return -EINVAL; > + > + count = n / sizeof(int); > + if ((count > WBUF_LEN) || (count % 2 == 0)) > + return -EINVAL; > + > + /* Wait any pending transfers to finish */ > + wait_event_interruptible(lirc_rx51->wqueue, lirc_rx51->wbuf_index < 0); If a signal arrives then this could return ERESTARTSYS and the condition might not have evaluated to true. > + > + if (copy_from_user(lirc_rx51->wbuf, buf, n)) > + return -EFAULT; > + > + /* Sanity check the input pulses */ > + for (i = 0; i < count; i++) > + if (lirc_rx51->wbuf[i] < 0) > + return -EINVAL; > + > + init_timing_params(lirc_rx51); > + if (count < WBUF_LEN) > + lirc_rx51->wbuf[count] = -1; /* Insert termination mark */ > + > + /* > + * Adjust latency requirements so the device doesn't go in too > + * deep sleep states > + */ > + lirc_rx51->pdata->set_max_mpu_wakeup_lat(lirc_rx51->dev, 50); > + > + lirc_rx51_on(lirc_rx51); > + lirc_rx51->wbuf_index = 1; > + pulse_timer_set_timeout(lirc_rx51, lirc_rx51->wbuf[0]); > + > + /* > + * Don't return back to the userspace until the transfer has > + * finished > + */ > + wait_event_interruptible(lirc_rx51->wqueue, lirc_rx51->wbuf_index < 0); same here. BTW so the semantics for lirc write() are that they complete when the data has been transmitted. This doesn't play well with signals, polling or non-blocking I/O. Is this deliberate or historical? I guess a lirc write() handler should ignore signals completely. > + > + /* We can sleep again */ > + lirc_rx51->pdata->set_max_mpu_wakeup_lat(lirc_rx51->dev, -1); > + > + return n; > +} > + > +static long lirc_rx51_ioctl(struct file *filep, > + unsigned int cmd, unsigned long arg) > +{ > + int result; > + unsigned long value; > + unsigned int ivalue; > + struct lirc_rx51 *lirc_rx51 = filep->private_data; > + > + switch (cmd) { > + case LIRC_GET_SEND_MODE: > + result = put_user(LIRC_MODE_PULSE, (unsigned long *)arg); > + if (result) > + return result; > + break; > + > + case LIRC_SET_SEND_MODE: > + result = get_user(value, (unsigned long *)arg); > + if (result) > + return result; > + > + /* only LIRC_MODE_PULSE supported */ > + if (value != LIRC_MODE_PULSE) > + return -ENOSYS; > + break; > + > + case LIRC_GET_REC_MODE: > + result = put_user(0, (unsigned long *) arg); > + if (result) > + return result; > + break; > + > + case LIRC_GET_LENGTH: > + return -ENOSYS; > + break; > + > + case LIRC_SET_SEND_DUTY_CYCLE: > + result = get_user(ivalue, (unsigned int *) arg); > + if (result) > + return result; > + > + if (ivalue <= 0 || ivalue > 100) { > + dev_err(lirc_rx51->dev, ": invalid duty cycle %d\n", > + ivalue); > + return -EINVAL; > + } > + > + lirc_rx51->duty_cycle = ivalue; > + break; > + > + case LIRC_SET_SEND_CARRIER: > + result = get_user(ivalue, (unsigned int *) arg); > + if (result) > + return result; > + > + if (ivalue > 500000 || ivalue < 20000) { > + dev_err(lirc_rx51->dev, ": invalid carrier freq %d\n", > + ivalue); > + return -EINVAL; > + } > + > + lirc_rx51->freq = ivalue; > + break; > + > + case LIRC_GET_FEATURES: > + result = put_user(LIRC_RX51_DRIVER_FEATURES, > + (unsigned long *) arg); > + if (result) > + return result; > + break; > + > + default: > + return -ENOIOCTLCMD; > + } > + > + return 0; > +} > + > +static int lirc_rx51_open(struct inode *inode, struct file *file) > +{ > + struct lirc_rx51 *lirc_rx51 = lirc_get_pdata(file); > + BUG_ON(!lirc_rx51); > + > + file->private_data = lirc_rx51; > + > + if (test_and_set_bit(1, &lirc_rx51->device_is_open)) > + return -EBUSY; > + > + return lirc_rx51_init_port(lirc_rx51); > +} > + > +static int lirc_rx51_release(struct inode *inode, struct file *file) > +{ > + struct lirc_rx51 *lirc_rx51 = file->private_data; > + > + lirc_rx51_free_port(lirc_rx51); > + > + clear_bit(1, &lirc_rx51->device_is_open); > + > + return 0; > +} > + > +static struct lirc_rx51 lirc_rx51 = { > + .freq = 38000, > + .duty_cycle = 50, > + .wbuf_index = -1, > +}; > + > +static const struct file_operations lirc_fops = { > + .owner = THIS_MODULE, > + .write = lirc_rx51_write, > + .unlocked_ioctl = lirc_rx51_ioctl, > + .read = lirc_dev_fop_read, > + .poll = lirc_dev_fop_poll, > + .open = lirc_rx51_open, > + .release = lirc_rx51_release, > +}; > + > +static struct lirc_driver lirc_rx51_driver = { > + .name = DRIVER_NAME, > + .minor = -1, > + .code_length = 1, > + .data = &lirc_rx51, > + .fops = &lirc_fops, > + .owner = THIS_MODULE, > +}; > + > +#ifdef CONFIG_PM > + > +static int lirc_rx51_suspend(struct platform_device *dev, pm_message_t state) > +{ > + /* > + * In case the device is still open, do not suspend. Normally > + * this should not be a problem as lircd only keeps the device > + * open only for short periods of time. We also don't want to > + * get involved with race conditions that might happen if we > + * were in a middle of a transmit. Thus, we defer any suspend > + * actions until transmit has completed. > + */ > + if (test_and_set_bit(1, &lirc_rx51.device_is_open)) > + return -EAGAIN; > + > + clear_bit(1, &lirc_rx51.device_is_open); > + > + return 0; > +} > + > +static int lirc_rx51_resume(struct platform_device *dev) > +{ > + return 0; > +} > + > +#else > + > +#define lirc_rx51_suspend NULL > +#define lirc_rx51_resume NULL > + > +#endif /* CONFIG_PM */ > + > +static int __devinit lirc_rx51_probe(struct platform_device *dev) > +{ > + lirc_rx51_driver.features = LIRC_RX51_DRIVER_FEATURES; > + lirc_rx51.pdata = dev->dev.platform_data; > + lirc_rx51.pwm_timer_num = lirc_rx51.pdata->pwm_timer; > + lirc_rx51.dev = &dev->dev; > + lirc_rx51_driver.dev = &dev->dev; > + lirc_rx51_driver.minor = lirc_register_driver(&lirc_rx51_driver); > + init_waitqueue_head(&lirc_rx51.wqueue); > + > + if (lirc_rx51_driver.minor < 0) { > + dev_err(lirc_rx51.dev, ": lirc_register_driver failed: %d\n", > + lirc_rx51_driver.minor); > + return lirc_rx51_driver.minor; > + } > + dev_info(lirc_rx51.dev, "registration ok, minor: %d, pwm: %d\n", > + lirc_rx51_driver.minor, lirc_rx51.pwm_timer_num); > + > + return 0; > +} > + > +static int __exit lirc_rx51_remove(struct platform_device *dev) > +{ > + return lirc_unregister_driver(lirc_rx51_driver.minor); > +} > + > +struct platform_driver lirc_rx51_platform_driver = { > + .probe = lirc_rx51_probe, > + .remove = __exit_p(lirc_rx51_remove), > + .suspend = lirc_rx51_suspend, > + .resume = lirc_rx51_resume, > + .remove = __exit_p(lirc_rx51_remove), .remove is here twice. > + .driver = { > + .name = DRIVER_NAME, > + .owner = THIS_MODULE, > + }, > +}; > + > +static int __init lirc_rx51_init(void) > +{ > + return platform_driver_register(&lirc_rx51_platform_driver); > +} > +module_init(lirc_rx51_init); > + > +static void __exit lirc_rx51_exit(void) > +{ > + platform_driver_unregister(&lirc_rx51_platform_driver); > +} > +module_exit(lirc_rx51_exit); > + > +MODULE_DESCRIPTION("LIRC TX driver for Nokia RX51"); > +MODULE_AUTHOR("Nokia Corporation"); > +MODULE_LICENSE("GPL"); > diff --git a/include/media/ir-rx51.h b/include/media/ir-rx51.h > new file mode 100644 > index 0000000..104aa89 > --- /dev/null > +++ b/include/media/ir-rx51.h > @@ -0,0 +1,10 @@ > +#ifndef _LIRC_RX51_H > +#define _LIRC_RX51_H > + > +struct lirc_rx51_platform_data { > + int pwm_timer; > + > + int(*set_max_mpu_wakeup_lat)(struct device *dev, long t); > +}; > + > +#endif > -- > 1.7.8.6 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-media" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 08/13/12 21:36, Sean Young wrote: > On Fri, Aug 10, 2012 at 01:16:36PM +0300, Timo Kokkonen wrote: >> +static ssize_t lirc_rx51_write(struct file *file, const char *buf, >> + size_t n, loff_t *ppos) >> +{ >> + int count, i; >> + struct lirc_rx51 *lirc_rx51 = file->private_data; >> + >> + if (n % sizeof(int)) >> + return -EINVAL; >> + >> + count = n / sizeof(int); >> + if ((count > WBUF_LEN) || (count % 2 == 0)) >> + return -EINVAL; >> + >> + /* Wait any pending transfers to finish */ >> + wait_event_interruptible(lirc_rx51->wqueue, lirc_rx51->wbuf_index < 0); > > If a signal arrives then this could return ERESTARTSYS and the condition > might not have evaluated to true. hmm.. The whole point of it is to wait if for any possibly pending transfers to finish. However, we don't allow the device to be opened more than once and parallel access doesn't make much sense here anyway. Only way we can end up waiting here is that the process is having multiple threads writing to the same file descriptor (or has inherited it from its parent), which doesn't make any sense. I think we could simply return -EBUSY in case previous transfer is still going on. I don't see any reason why we should wait here. > >> + >> + if (copy_from_user(lirc_rx51->wbuf, buf, n)) >> + return -EFAULT; >> + >> + /* Sanity check the input pulses */ >> + for (i = 0; i < count; i++) >> + if (lirc_rx51->wbuf[i] < 0) >> + return -EINVAL; >> + >> + init_timing_params(lirc_rx51); >> + if (count < WBUF_LEN) >> + lirc_rx51->wbuf[count] = -1; /* Insert termination mark */ >> + >> + /* >> + * Adjust latency requirements so the device doesn't go in too >> + * deep sleep states >> + */ >> + lirc_rx51->pdata->set_max_mpu_wakeup_lat(lirc_rx51->dev, 50); >> + >> + lirc_rx51_on(lirc_rx51); >> + lirc_rx51->wbuf_index = 1; >> + pulse_timer_set_timeout(lirc_rx51, lirc_rx51->wbuf[0]); >> + >> + /* >> + * Don't return back to the userspace until the transfer has >> + * finished >> + */ >> + wait_event_interruptible(lirc_rx51->wqueue, lirc_rx51->wbuf_index < 0); > > same here. > > BTW so the semantics for lirc write() are that they complete when the > data has been transmitted. This doesn't play well with signals, polling > or non-blocking I/O. Is this deliberate or historical? > > I guess a lirc write() handler should ignore signals completely. > I'll change it to wait_event_timeout instead. >> + >> +struct platform_driver lirc_rx51_platform_driver = { >> + .probe = lirc_rx51_probe, >> + .remove = __exit_p(lirc_rx51_remove), >> + .suspend = lirc_rx51_suspend, >> + .resume = lirc_rx51_resume, >> + .remove = __exit_p(lirc_rx51_remove), > > .remove is here twice. hehe.. I remember I was supposed to write a patch for that five years ago but I was busy :) Thanks for your review. Will send round three. -Timo -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig index 5180390..ab35d2e 100644 --- a/drivers/media/rc/Kconfig +++ b/drivers/media/rc/Kconfig @@ -270,6 +270,16 @@ config IR_IGUANA To compile this driver as a module, choose M here: the module will be called iguanair. +config IR_RX51 + tristate "Nokia N900 IR transmitter diode + depends on MACH_NOKIA_RX51 && OMAP_DM_TIMER + ---help--- + Say Y or M here if you want to enable support for the IR + transmitter diode built in the Nokia N900 (RX51) device. + + The driver uses omap DM timers for gereating the carrier + wave and pulses. + config RC_LOOPBACK tristate "Remote Control Loopback Driver" depends on RC_CORE diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile index f871d19..d384f30 100644 --- a/drivers/media/rc/Makefile +++ b/drivers/media/rc/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_IR_FINTEK) += fintek-cir.o obj-$(CONFIG_IR_NUVOTON) += nuvoton-cir.o obj-$(CONFIG_IR_ENE) += ene_ir.o obj-$(CONFIG_IR_REDRAT3) += redrat3.o +obj-$(CONFIG_IR_RX51) += ir-rx51.o obj-$(CONFIG_IR_STREAMZAP) += streamzap.o obj-$(CONFIG_IR_WINBOND_CIR) += winbond-cir.o obj-$(CONFIG_RC_LOOPBACK) += rc-loopback.o diff --git a/drivers/media/rc/ir-rx51.c b/drivers/media/rc/ir-rx51.c new file mode 100644 index 0000000..9487dd3 --- /dev/null +++ b/drivers/media/rc/ir-rx51.c @@ -0,0 +1,496 @@ +/* + * Copyright (C) 2008 Nokia Corporation + * + * Based on lirc_serial.c + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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/interrupt.h> +#include <linux/uaccess.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/wait.h> + +#include <plat/dmtimer.h> +#include <plat/clock.h> +#include <plat/omap-pm.h> + +#include <media/lirc.h> +#include <media/lirc_dev.h> +#include <media/ir-rx51.h> + +#define LIRC_RX51_DRIVER_FEATURES (LIRC_CAN_SET_SEND_DUTY_CYCLE | \ + LIRC_CAN_SET_SEND_CARRIER | \ + LIRC_CAN_SEND_PULSE) + +#define DRIVER_NAME "lirc_rx51" + +#define WBUF_LEN 256 + +#define TIMER_MAX_VALUE 0xffffffff + +struct lirc_rx51 { + struct omap_dm_timer *pwm_timer; + struct omap_dm_timer *pulse_timer; + struct device *dev; + struct lirc_rx51_platform_data *pdata; + wait_queue_head_t wqueue; + + unsigned long fclk_khz; + unsigned int freq; /* carrier frequency */ + unsigned int duty_cycle; /* carrier duty cycle */ + unsigned int irq_num; + unsigned int match; + int wbuf[WBUF_LEN]; + int wbuf_index; + unsigned long device_is_open; + unsigned int pwm_timer_num; +}; + +static void lirc_rx51_on(struct lirc_rx51 *lirc_rx51) +{ + omap_dm_timer_set_pwm(lirc_rx51->pwm_timer, 0, 1, + OMAP_TIMER_TRIGGER_OVERFLOW_AND_COMPARE); +} + +static void lirc_rx51_off(struct lirc_rx51 *lirc_rx51) +{ + omap_dm_timer_set_pwm(lirc_rx51->pwm_timer, 0, 1, + OMAP_TIMER_TRIGGER_NONE); +} + +static int init_timing_params(struct lirc_rx51 *lirc_rx51) +{ + u32 load, match; + + load = -(lirc_rx51->fclk_khz * 1000 / lirc_rx51->freq); + match = -(lirc_rx51->duty_cycle * -load / 100); + omap_dm_timer_set_load(lirc_rx51->pwm_timer, 1, load); + omap_dm_timer_set_match(lirc_rx51->pwm_timer, 1, match); + omap_dm_timer_write_counter(lirc_rx51->pwm_timer, TIMER_MAX_VALUE - 2); + omap_dm_timer_start(lirc_rx51->pwm_timer); + omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, 0); + omap_dm_timer_start(lirc_rx51->pulse_timer); + + lirc_rx51->match = 0; + + return 0; +} + +#define tics_after(a, b) ((long)(b) - (long)(a) < 0) + +static int pulse_timer_set_timeout(struct lirc_rx51 *lirc_rx51, int usec) +{ + int counter; + + BUG_ON(usec < 0); + + if (lirc_rx51->match == 0) + counter = omap_dm_timer_read_counter(lirc_rx51->pulse_timer); + else + counter = lirc_rx51->match; + + counter += (u32)(lirc_rx51->fclk_khz * usec / (1000)); + omap_dm_timer_set_match(lirc_rx51->pulse_timer, 1, counter); + omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, + OMAP_TIMER_INT_MATCH); + if (tics_after(omap_dm_timer_read_counter(lirc_rx51->pulse_timer), + counter)) { + return 1; + } + return 0; +} + +static irqreturn_t lirc_rx51_interrupt_handler(int irq, void *ptr) +{ + unsigned int retval; + struct lirc_rx51 *lirc_rx51 = ptr; + + retval = omap_dm_timer_read_status(lirc_rx51->pulse_timer); + if (!retval) + return IRQ_NONE; + + if ((retval & ~OMAP_TIMER_INT_MATCH)) + dev_err_ratelimited(lirc_rx51->dev, + ": Unexpected interrupt source: %x\n", retval); + + omap_dm_timer_write_status(lirc_rx51->pulse_timer, 7); + if (lirc_rx51->wbuf_index < 0) { + dev_err_ratelimited(lirc_rx51->dev, + ": BUG wbuf_index has value of %i\n", + lirc_rx51->wbuf_index); + goto end; + } + + /* + * If we happen to hit an odd latency spike, loop through the + * pulses until we catch up. + */ + do { + if (lirc_rx51->wbuf_index >= WBUF_LEN) + goto end; + if (lirc_rx51->wbuf[lirc_rx51->wbuf_index] == -1) + goto end; + + if (lirc_rx51->wbuf_index % 2) + lirc_rx51_off(lirc_rx51); + else + lirc_rx51_on(lirc_rx51); + + retval = pulse_timer_set_timeout(lirc_rx51, + lirc_rx51->wbuf[lirc_rx51->wbuf_index]); + lirc_rx51->wbuf_index++; + + } while (retval); + + return IRQ_HANDLED; +end: + /* Stop TX here */ + lirc_rx51_off(lirc_rx51); + lirc_rx51->wbuf_index = -1; + omap_dm_timer_stop(lirc_rx51->pwm_timer); + omap_dm_timer_stop(lirc_rx51->pulse_timer); + omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, 0); + wake_up_interruptible(&lirc_rx51->wqueue); + + return IRQ_HANDLED; +} + +static int lirc_rx51_init_port(struct lirc_rx51 *lirc_rx51) +{ + struct clk *clk_fclk; + int retval, pwm_timer = lirc_rx51->pwm_timer_num; + + lirc_rx51->pwm_timer = omap_dm_timer_request_specific(pwm_timer); + if (lirc_rx51->pwm_timer == NULL) { + dev_err(lirc_rx51->dev, ": Error requesting GPT%d timer\n", + pwm_timer); + return -EBUSY; + } + + lirc_rx51->pulse_timer = omap_dm_timer_request(); + if (lirc_rx51->pulse_timer == NULL) { + dev_err(lirc_rx51->dev, ": Error requesting pulse timer\n"); + retval = -EBUSY; + goto err1; + } + + omap_dm_timer_set_source(lirc_rx51->pwm_timer, OMAP_TIMER_SRC_SYS_CLK); + omap_dm_timer_set_source(lirc_rx51->pulse_timer, + OMAP_TIMER_SRC_SYS_CLK); + + omap_dm_timer_enable(lirc_rx51->pwm_timer); + omap_dm_timer_enable(lirc_rx51->pulse_timer); + + lirc_rx51->irq_num = omap_dm_timer_get_irq(lirc_rx51->pulse_timer); + retval = request_irq(lirc_rx51->irq_num, lirc_rx51_interrupt_handler, + IRQF_DISABLED | IRQF_SHARED, + "lirc_pulse_timer", lirc_rx51); + if (retval) { + dev_err(lirc_rx51->dev, ": Failed to request interrupt line\n"); + goto err2; + } + + clk_fclk = omap_dm_timer_get_fclk(lirc_rx51->pwm_timer); + lirc_rx51->fclk_khz = clk_fclk->rate / 1000; + + return 0; + +err2: + omap_dm_timer_free(lirc_rx51->pulse_timer); +err1: + omap_dm_timer_free(lirc_rx51->pwm_timer); + + return retval; +} + +static int lirc_rx51_free_port(struct lirc_rx51 *lirc_rx51) +{ + omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, 0); + free_irq(lirc_rx51->irq_num, lirc_rx51); + lirc_rx51_off(lirc_rx51); + omap_dm_timer_disable(lirc_rx51->pwm_timer); + omap_dm_timer_disable(lirc_rx51->pulse_timer); + omap_dm_timer_free(lirc_rx51->pwm_timer); + omap_dm_timer_free(lirc_rx51->pulse_timer); + lirc_rx51->wbuf_index = -1; + + return 0; +} + +static ssize_t lirc_rx51_write(struct file *file, const char *buf, + size_t n, loff_t *ppos) +{ + int count, i; + struct lirc_rx51 *lirc_rx51 = file->private_data; + + if (n % sizeof(int)) + return -EINVAL; + + count = n / sizeof(int); + if ((count > WBUF_LEN) || (count % 2 == 0)) + return -EINVAL; + + /* Wait any pending transfers to finish */ + wait_event_interruptible(lirc_rx51->wqueue, lirc_rx51->wbuf_index < 0); + + if (copy_from_user(lirc_rx51->wbuf, buf, n)) + return -EFAULT; + + /* Sanity check the input pulses */ + for (i = 0; i < count; i++) + if (lirc_rx51->wbuf[i] < 0) + return -EINVAL; + + init_timing_params(lirc_rx51); + if (count < WBUF_LEN) + lirc_rx51->wbuf[count] = -1; /* Insert termination mark */ + + /* + * Adjust latency requirements so the device doesn't go in too + * deep sleep states + */ + lirc_rx51->pdata->set_max_mpu_wakeup_lat(lirc_rx51->dev, 50); + + lirc_rx51_on(lirc_rx51); + lirc_rx51->wbuf_index = 1; + pulse_timer_set_timeout(lirc_rx51, lirc_rx51->wbuf[0]); + + /* + * Don't return back to the userspace until the transfer has + * finished + */ + wait_event_interruptible(lirc_rx51->wqueue, lirc_rx51->wbuf_index < 0); + + /* We can sleep again */ + lirc_rx51->pdata->set_max_mpu_wakeup_lat(lirc_rx51->dev, -1); + + return n; +} + +static long lirc_rx51_ioctl(struct file *filep, + unsigned int cmd, unsigned long arg) +{ + int result; + unsigned long value; + unsigned int ivalue; + struct lirc_rx51 *lirc_rx51 = filep->private_data; + + switch (cmd) { + case LIRC_GET_SEND_MODE: + result = put_user(LIRC_MODE_PULSE, (unsigned long *)arg); + if (result) + return result; + break; + + case LIRC_SET_SEND_MODE: + result = get_user(value, (unsigned long *)arg); + if (result) + return result; + + /* only LIRC_MODE_PULSE supported */ + if (value != LIRC_MODE_PULSE) + return -ENOSYS; + break; + + case LIRC_GET_REC_MODE: + result = put_user(0, (unsigned long *) arg); + if (result) + return result; + break; + + case LIRC_GET_LENGTH: + return -ENOSYS; + break; + + case LIRC_SET_SEND_DUTY_CYCLE: + result = get_user(ivalue, (unsigned int *) arg); + if (result) + return result; + + if (ivalue <= 0 || ivalue > 100) { + dev_err(lirc_rx51->dev, ": invalid duty cycle %d\n", + ivalue); + return -EINVAL; + } + + lirc_rx51->duty_cycle = ivalue; + break; + + case LIRC_SET_SEND_CARRIER: + result = get_user(ivalue, (unsigned int *) arg); + if (result) + return result; + + if (ivalue > 500000 || ivalue < 20000) { + dev_err(lirc_rx51->dev, ": invalid carrier freq %d\n", + ivalue); + return -EINVAL; + } + + lirc_rx51->freq = ivalue; + break; + + case LIRC_GET_FEATURES: + result = put_user(LIRC_RX51_DRIVER_FEATURES, + (unsigned long *) arg); + if (result) + return result; + break; + + default: + return -ENOIOCTLCMD; + } + + return 0; +} + +static int lirc_rx51_open(struct inode *inode, struct file *file) +{ + struct lirc_rx51 *lirc_rx51 = lirc_get_pdata(file); + BUG_ON(!lirc_rx51); + + file->private_data = lirc_rx51; + + if (test_and_set_bit(1, &lirc_rx51->device_is_open)) + return -EBUSY; + + return lirc_rx51_init_port(lirc_rx51); +} + +static int lirc_rx51_release(struct inode *inode, struct file *file) +{ + struct lirc_rx51 *lirc_rx51 = file->private_data; + + lirc_rx51_free_port(lirc_rx51); + + clear_bit(1, &lirc_rx51->device_is_open); + + return 0; +} + +static struct lirc_rx51 lirc_rx51 = { + .freq = 38000, + .duty_cycle = 50, + .wbuf_index = -1, +}; + +static const struct file_operations lirc_fops = { + .owner = THIS_MODULE, + .write = lirc_rx51_write, + .unlocked_ioctl = lirc_rx51_ioctl, + .read = lirc_dev_fop_read, + .poll = lirc_dev_fop_poll, + .open = lirc_rx51_open, + .release = lirc_rx51_release, +}; + +static struct lirc_driver lirc_rx51_driver = { + .name = DRIVER_NAME, + .minor = -1, + .code_length = 1, + .data = &lirc_rx51, + .fops = &lirc_fops, + .owner = THIS_MODULE, +}; + +#ifdef CONFIG_PM + +static int lirc_rx51_suspend(struct platform_device *dev, pm_message_t state) +{ + /* + * In case the device is still open, do not suspend. Normally + * this should not be a problem as lircd only keeps the device + * open only for short periods of time. We also don't want to + * get involved with race conditions that might happen if we + * were in a middle of a transmit. Thus, we defer any suspend + * actions until transmit has completed. + */ + if (test_and_set_bit(1, &lirc_rx51.device_is_open)) + return -EAGAIN; + + clear_bit(1, &lirc_rx51.device_is_open); + + return 0; +} + +static int lirc_rx51_resume(struct platform_device *dev) +{ + return 0; +} + +#else + +#define lirc_rx51_suspend NULL +#define lirc_rx51_resume NULL + +#endif /* CONFIG_PM */ + +static int __devinit lirc_rx51_probe(struct platform_device *dev) +{ + lirc_rx51_driver.features = LIRC_RX51_DRIVER_FEATURES; + lirc_rx51.pdata = dev->dev.platform_data; + lirc_rx51.pwm_timer_num = lirc_rx51.pdata->pwm_timer; + lirc_rx51.dev = &dev->dev; + lirc_rx51_driver.dev = &dev->dev; + lirc_rx51_driver.minor = lirc_register_driver(&lirc_rx51_driver); + init_waitqueue_head(&lirc_rx51.wqueue); + + if (lirc_rx51_driver.minor < 0) { + dev_err(lirc_rx51.dev, ": lirc_register_driver failed: %d\n", + lirc_rx51_driver.minor); + return lirc_rx51_driver.minor; + } + dev_info(lirc_rx51.dev, "registration ok, minor: %d, pwm: %d\n", + lirc_rx51_driver.minor, lirc_rx51.pwm_timer_num); + + return 0; +} + +static int __exit lirc_rx51_remove(struct platform_device *dev) +{ + return lirc_unregister_driver(lirc_rx51_driver.minor); +} + +struct platform_driver lirc_rx51_platform_driver = { + .probe = lirc_rx51_probe, + .remove = __exit_p(lirc_rx51_remove), + .suspend = lirc_rx51_suspend, + .resume = lirc_rx51_resume, + .remove = __exit_p(lirc_rx51_remove), + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init lirc_rx51_init(void) +{ + return platform_driver_register(&lirc_rx51_platform_driver); +} +module_init(lirc_rx51_init); + +static void __exit lirc_rx51_exit(void) +{ + platform_driver_unregister(&lirc_rx51_platform_driver); +} +module_exit(lirc_rx51_exit); + +MODULE_DESCRIPTION("LIRC TX driver for Nokia RX51"); +MODULE_AUTHOR("Nokia Corporation"); +MODULE_LICENSE("GPL"); diff --git a/include/media/ir-rx51.h b/include/media/ir-rx51.h new file mode 100644 index 0000000..104aa89 --- /dev/null +++ b/include/media/ir-rx51.h @@ -0,0 +1,10 @@ +#ifndef _LIRC_RX51_H +#define _LIRC_RX51_H + +struct lirc_rx51_platform_data { + int pwm_timer; + + int(*set_max_mpu_wakeup_lat)(struct device *dev, long t); +}; + +#endif
This is the driver for the IR transmitter diode found on the Nokia N900 (also known as RX51) device. The driver is mostly the same as found in the original 2.6.28 based kernel that comes with the device. The following modifications have been made compared to the original driver version: - Adopt to the changes that has happen in the kernel during the past five years, such as the change in the include paths - The OMAP DM-timers require much more care nowadays. The timers need to be enabled and disabled or otherwise many actions fail. Timers must not be freed without first stopping them or otherwise the timer cannot be requested again. The code has been tested with sending IR codes with N900 device running Debian userland. The device receiving the codes was Anysee DVB-C USB receiver. Signed-off-by: Timo Kokkonen <timo.t.kokkonen@iki.fi> --- drivers/media/rc/Kconfig | 10 + drivers/media/rc/Makefile | 1 + drivers/media/rc/ir-rx51.c | 496 ++++++++++++++++++++++++++++++++++++++++++++ include/media/ir-rx51.h | 10 + 4 files changed, 517 insertions(+), 0 deletions(-) create mode 100644 drivers/media/rc/ir-rx51.c create mode 100644 include/media/ir-rx51.h