From b4269ab1d08d22959ec26ce1d31a45a1c5e85191 Mon Sep 17 00:00:00 2001 From: Aron Szabo Date: Sat, 16 Jun 2012 12:15:55 +0200 Subject: [PATCH] lirc: added support for RaspberryPi GPIO lirc_rpi: Use read_current_timer to determine transmitter delay. Thanks to jjmz and others See: https://github.com/raspberrypi/linux/issues/525 lirc: Remove restriction on gpio pins that can be used with lirc Compute Module, for example could use different pins lirc_rpi: Add parameter to specify input pin pull Depending on the connected IR circuitry it might be desirable to change the gpios internal pull from it pull-down default behaviour. Add a module parameter to allow the user to set it explicitly. Signed-off-by: Julian Scheel lirc-rpi: Use the higher-level irq control functions This module used to access the irq_chip methods of the gpio controller directly, rather than going through the standard enable_irq/irq_set_irq_type functions. This caused problems on pinctrl-bcm2835 which only implements the irq_enable/disable methods and not irq_unmask/mask. lirc-rpi: Correct the interrupt usage 1) Correct the use of enable_irq (i.e. don't call it so often) 2) Correct the shutdown sequence. 3) Avoid a bcm2708_gpio driver quirk by setting the irq flags earlier lirc-rpi: use getnstimeofday instead of read_current_timer read_current_timer isn't guaranteed to return values in microseconds, and indeed it doesn't on a Pi2. Issue: linux#827 lirc-rpi: Add device tree support, and a suitable overlay The overlay supports DT parameters that match the old module parameters, except that gpio_in_pull should be set using the strings "up", "down" or "off". lirc-rpi: Also support pinctrl-bcm2835 in non-DT mode --- drivers/staging/media/lirc/Kconfig | 6 + drivers/staging/media/lirc/Makefile | 1 + drivers/staging/media/lirc/lirc_rpi.c | 730 ++++++++++++++++++++++++++++++++++ include/linux/platform_data/bcm2708.h | 23 ++ 4 files changed, 760 insertions(+) create mode 100644 drivers/staging/media/lirc/lirc_rpi.c create mode 100644 include/linux/platform_data/bcm2708.h --- a/drivers/staging/media/lirc/Kconfig +++ b/drivers/staging/media/lirc/Kconfig @@ -32,6 +32,12 @@ config LIRC_PARALLEL help Driver for Homebrew Parallel Port Receivers +config LIRC_RPI + tristate "Homebrew GPIO Port Receiver/Transmitter for the RaspberryPi" + depends on LIRC + help + Driver for Homebrew GPIO Port Receiver/Transmitter for the RaspberryPi + config LIRC_SASEM tristate "Sasem USB IR Remote" depends on LIRC && USB --- a/drivers/staging/media/lirc/Makefile +++ b/drivers/staging/media/lirc/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_LIRC_BT829) += lirc_bt829.o obj-$(CONFIG_LIRC_IMON) += lirc_imon.o obj-$(CONFIG_LIRC_PARALLEL) += lirc_parallel.o +obj-$(CONFIG_LIRC_RPI) += lirc_rpi.o obj-$(CONFIG_LIRC_SASEM) += lirc_sasem.o obj-$(CONFIG_LIRC_SERIAL) += lirc_serial.o obj-$(CONFIG_LIRC_SIR) += lirc_sir.o --- /dev/null +++ b/drivers/staging/media/lirc/lirc_rpi.c @@ -0,0 +1,730 @@ +/* + * lirc_rpi.c + * + * lirc_rpi - Device driver that records pulse- and pause-lengths + * (space-lengths) (just like the lirc_serial driver does) + * between GPIO interrupt events on the Raspberry Pi. + * Lots of code has been taken from the lirc_serial module, + * so I would like say thanks to the authors. + * + * Copyright (C) 2012 Aron Robert Szabo , + * Michael Bishop + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define LIRC_DRIVER_NAME "lirc_rpi" +#define RBUF_LEN 256 +#define LIRC_TRANSMITTER_LATENCY 50 + +#ifndef MAX_UDELAY_MS +#define MAX_UDELAY_US 5000 +#else +#define MAX_UDELAY_US (MAX_UDELAY_MS*1000) +#endif + +#define dprintk(fmt, args...) \ + do { \ + if (debug) \ + printk(KERN_DEBUG LIRC_DRIVER_NAME ": " \ + fmt, ## args); \ + } while (0) + +/* module parameters */ + +/* set the default GPIO input pin */ +static int gpio_in_pin = 18; +/* set the default pull behaviour for input pin */ +static int gpio_in_pull = BCM2708_PULL_DOWN; +/* set the default GPIO output pin */ +static int gpio_out_pin = 17; +/* enable debugging messages */ +static bool debug; +/* -1 = auto, 0 = active high, 1 = active low */ +static int sense = -1; +/* use softcarrier by default */ +static bool softcarrier = 1; +/* 0 = do not invert output, 1 = invert output */ +static bool invert = 0; + +struct gpio_chip *gpiochip; +static int irq_num; + +/* forward declarations */ +static long send_pulse(unsigned long length); +static void send_space(long length); +static void lirc_rpi_exit(void); + +static struct platform_device *lirc_rpi_dev; +static struct timeval lasttv = { 0, 0 }; +static struct lirc_buffer rbuf; +static spinlock_t lock; + +/* initialized/set in init_timing_params() */ +static unsigned int freq = 38000; +static unsigned int duty_cycle = 50; +static unsigned long period; +static unsigned long pulse_width; +static unsigned long space_width; + +static void safe_udelay(unsigned long usecs) +{ + while (usecs > MAX_UDELAY_US) { + udelay(MAX_UDELAY_US); + usecs -= MAX_UDELAY_US; + } + udelay(usecs); +} + +static unsigned long read_current_us(void) +{ + struct timespec now; + getnstimeofday(&now); + return (now.tv_sec * 1000000) + (now.tv_nsec/1000); +} + +static int init_timing_params(unsigned int new_duty_cycle, + unsigned int new_freq) +{ + if (1000 * 1000000L / new_freq * new_duty_cycle / 100 <= + LIRC_TRANSMITTER_LATENCY) + return -EINVAL; + if (1000 * 1000000L / new_freq * (100 - new_duty_cycle) / 100 <= + LIRC_TRANSMITTER_LATENCY) + return -EINVAL; + duty_cycle = new_duty_cycle; + freq = new_freq; + period = 1000 * 1000000L / freq; + pulse_width = period * duty_cycle / 100; + space_width = period - pulse_width; + dprintk("in init_timing_params, freq=%d pulse=%ld, " + "space=%ld\n", freq, pulse_width, space_width); + return 0; +} + +static long send_pulse_softcarrier(unsigned long length) +{ + int flag; + unsigned long actual, target; + unsigned long actual_us, initial_us, target_us; + + length *= 1000; + + actual = 0; target = 0; flag = 0; + actual_us = read_current_us(); + + while (actual < length) { + if (flag) { + gpiochip->set(gpiochip, gpio_out_pin, invert); + target += space_width; + } else { + gpiochip->set(gpiochip, gpio_out_pin, !invert); + target += pulse_width; + } + initial_us = actual_us; + target_us = actual_us + (target - actual) / 1000; + /* + * Note - we've checked in ioctl that the pulse/space + * widths are big enough so that d is > 0 + */ + if ((int)(target_us - actual_us) > 0) + udelay(target_us - actual_us); + actual_us = read_current_us(); + actual += (actual_us - initial_us) * 1000; + flag = !flag; + } + return (actual-length) / 1000; +} + +static long send_pulse(unsigned long length) +{ + if (length <= 0) + return 0; + + if (softcarrier) { + return send_pulse_softcarrier(length); + } else { + gpiochip->set(gpiochip, gpio_out_pin, !invert); + safe_udelay(length); + return 0; + } +} + +static void send_space(long length) +{ + gpiochip->set(gpiochip, gpio_out_pin, invert); + if (length <= 0) + return; + safe_udelay(length); +} + +static void rbwrite(int l) +{ + if (lirc_buffer_full(&rbuf)) { + /* no new signals will be accepted */ + dprintk("Buffer overrun\n"); + return; + } + lirc_buffer_write(&rbuf, (void *)&l); +} + +static void frbwrite(int l) +{ + /* simple noise filter */ + static int pulse, space; + static unsigned int ptr; + + if (ptr > 0 && (l & PULSE_BIT)) { + pulse += l & PULSE_MASK; + if (pulse > 250) { + rbwrite(space); + rbwrite(pulse | PULSE_BIT); + ptr = 0; + pulse = 0; + } + return; + } + if (!(l & PULSE_BIT)) { + if (ptr == 0) { + if (l > 20000) { + space = l; + ptr++; + return; + } + } else { + if (l > 20000) { + space += pulse; + if (space > PULSE_MASK) + space = PULSE_MASK; + space += l; + if (space > PULSE_MASK) + space = PULSE_MASK; + pulse = 0; + return; + } + rbwrite(space); + rbwrite(pulse | PULSE_BIT); + ptr = 0; + pulse = 0; + } + } + rbwrite(l); +} + +static irqreturn_t irq_handler(int i, void *blah, struct pt_regs *regs) +{ + struct timeval tv; + long deltv; + int data; + int signal; + + /* use the GPIO signal level */ + signal = gpiochip->get(gpiochip, gpio_in_pin); + + if (sense != -1) { + /* get current time */ + do_gettimeofday(&tv); + + /* calc time since last interrupt in microseconds */ + deltv = tv.tv_sec-lasttv.tv_sec; + if (tv.tv_sec < lasttv.tv_sec || + (tv.tv_sec == lasttv.tv_sec && + tv.tv_usec < lasttv.tv_usec)) { + printk(KERN_WARNING LIRC_DRIVER_NAME + ": AIEEEE: your clock just jumped backwards\n"); + printk(KERN_WARNING LIRC_DRIVER_NAME + ": %d %d %lx %lx %lx %lx\n", signal, sense, + tv.tv_sec, lasttv.tv_sec, + tv.tv_usec, lasttv.tv_usec); + data = PULSE_MASK; + } else if (deltv > 15) { + data = PULSE_MASK; /* really long time */ + if (!(signal^sense)) { + /* sanity check */ + printk(KERN_WARNING LIRC_DRIVER_NAME + ": AIEEEE: %d %d %lx %lx %lx %lx\n", + signal, sense, tv.tv_sec, lasttv.tv_sec, + tv.tv_usec, lasttv.tv_usec); + /* + * detecting pulse while this + * MUST be a space! + */ + sense = sense ? 0 : 1; + } + } else { + data = (int) (deltv*1000000 + + (tv.tv_usec - lasttv.tv_usec)); + } + frbwrite(signal^sense ? data : (data|PULSE_BIT)); + lasttv = tv; + wake_up_interruptible(&rbuf.wait_poll); + } + + return IRQ_HANDLED; +} + +static int is_right_chip(struct gpio_chip *chip, void *data) +{ + dprintk("is_right_chip %s %d\n", chip->label, strcmp(data, chip->label)); + + if (strcmp(data, chip->label) == 0) + return 1; + return 0; +} + +static inline int read_bool_property(const struct device_node *np, + const char *propname, + bool *out_value) +{ + u32 value = 0; + int err = of_property_read_u32(np, propname, &value); + if (err == 0) + *out_value = (value != 0); + return err; +} + +static void read_pin_settings(struct device_node *node) +{ + u32 pin; + int index; + + for (index = 0; + of_property_read_u32_index( + node, + "brcm,pins", + index, + &pin) == 0; + index++) { + u32 function; + int err; + err = of_property_read_u32_index( + node, + "brcm,function", + index, + &function); + if (err == 0) { + if (function == 1) /* Output */ + gpio_out_pin = pin; + else if (function == 0) /* Input */ + gpio_in_pin = pin; + } + } +} + +static int init_port(void) +{ + int i, nlow, nhigh; + struct device_node *node; + + node = lirc_rpi_dev->dev.of_node; + + gpiochip = gpiochip_find("bcm2708_gpio", is_right_chip); + + /* + * Because of the lack of a setpull function, only support + * pinctrl-bcm2835 if using device tree. + */ + if (!gpiochip && node) + gpiochip = gpiochip_find("pinctrl-bcm2835", is_right_chip); + + if (!gpiochip) { + pr_err(LIRC_DRIVER_NAME ": gpio chip not found!\n"); + return -ENODEV; + } + + if (node) { + struct device_node *pins_node; + + pins_node = of_parse_phandle(node, "pinctrl-0", 0); + if (!pins_node) { + printk(KERN_ERR LIRC_DRIVER_NAME + ": pinctrl settings not found!\n"); + return -EINVAL; + } + + read_pin_settings(pins_node); + + of_property_read_u32(node, "rpi,sense", &sense); + + read_bool_property(node, "rpi,softcarrier", &softcarrier); + + read_bool_property(node, "rpi,invert", &invert); + + read_bool_property(node, "rpi,debug", &debug); + + } else { + return -EINVAL; + } + + gpiochip->set(gpiochip, gpio_out_pin, invert); + + irq_num = gpiochip->to_irq(gpiochip, gpio_in_pin); + dprintk("to_irq %d\n", irq_num); + + /* if pin is high, then this must be an active low receiver. */ + if (sense == -1) { + /* wait 1/2 sec for the power supply */ + msleep(500); + + /* + * probe 9 times every 0.04s, collect "votes" for + * active high/low + */ + nlow = 0; + nhigh = 0; + for (i = 0; i < 9; i++) { + if (gpiochip->get(gpiochip, gpio_in_pin)) + nlow++; + else + nhigh++; + msleep(40); + } + sense = (nlow >= nhigh ? 1 : 0); + printk(KERN_INFO LIRC_DRIVER_NAME + ": auto-detected active %s receiver on GPIO pin %d\n", + sense ? "low" : "high", gpio_in_pin); + } else { + printk(KERN_INFO LIRC_DRIVER_NAME + ": manually using active %s receiver on GPIO pin %d\n", + sense ? "low" : "high", gpio_in_pin); + } + + return 0; +} + +// called when the character device is opened +static int set_use_inc(void *data) +{ + int result; + + /* initialize timestamp */ + do_gettimeofday(&lasttv); + + result = request_irq(irq_num, + (irq_handler_t) irq_handler, + IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING, + LIRC_DRIVER_NAME, (void*) 0); + + switch (result) { + case -EBUSY: + printk(KERN_ERR LIRC_DRIVER_NAME + ": IRQ %d is busy\n", + irq_num); + return -EBUSY; + case -EINVAL: + printk(KERN_ERR LIRC_DRIVER_NAME + ": Bad irq number or handler\n"); + return -EINVAL; + default: + dprintk("Interrupt %d obtained\n", + irq_num); + break; + }; + + /* initialize pulse/space widths */ + init_timing_params(duty_cycle, freq); + + return 0; +} + +static void set_use_dec(void *data) +{ + /* GPIO Pin Falling/Rising Edge Detect Disable */ + irq_set_irq_type(irq_num, 0); + disable_irq(irq_num); + + free_irq(irq_num, (void *) 0); + + dprintk(KERN_INFO LIRC_DRIVER_NAME + ": freed IRQ %d\n", irq_num); +} + +static ssize_t lirc_write(struct file *file, const char *buf, + size_t n, loff_t *ppos) +{ + int i, count; + unsigned long flags; + long delta = 0; + int *wbuf; + + count = n / sizeof(int); + if (n % sizeof(int) || count % 2 == 0) + return -EINVAL; + wbuf = memdup_user(buf, n); + if (IS_ERR(wbuf)) + return PTR_ERR(wbuf); + spin_lock_irqsave(&lock, flags); + + for (i = 0; i < count; i++) { + if (i%2) + send_space(wbuf[i] - delta); + else + delta = send_pulse(wbuf[i]); + } + gpiochip->set(gpiochip, gpio_out_pin, invert); + + spin_unlock_irqrestore(&lock, flags); + kfree(wbuf); + return n; +} + +static long lirc_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) +{ + int result; + __u32 value; + + switch (cmd) { + case LIRC_GET_SEND_MODE: + return -ENOIOCTLCMD; + break; + + case LIRC_SET_SEND_MODE: + result = get_user(value, (__u32 *) arg); + if (result) + return result; + /* only LIRC_MODE_PULSE supported */ + if (value != LIRC_MODE_PULSE) + return -ENOSYS; + break; + + case LIRC_GET_LENGTH: + return -ENOSYS; + break; + + case LIRC_SET_SEND_DUTY_CYCLE: + dprintk("SET_SEND_DUTY_CYCLE\n"); + result = get_user(value, (__u32 *) arg); + if (result) + return result; + if (value <= 0 || value > 100) + return -EINVAL; + return init_timing_params(value, freq); + break; + + case LIRC_SET_SEND_CARRIER: + dprintk("SET_SEND_CARRIER\n"); + result = get_user(value, (__u32 *) arg); + if (result) + return result; + if (value > 500000 || value < 20000) + return -EINVAL; + return init_timing_params(duty_cycle, value); + break; + + default: + return lirc_dev_fop_ioctl(filep, cmd, arg); + } + return 0; +} + +static const struct file_operations lirc_fops = { + .owner = THIS_MODULE, + .write = lirc_write, + .unlocked_ioctl = lirc_ioctl, + .read = lirc_dev_fop_read, + .poll = lirc_dev_fop_poll, + .open = lirc_dev_fop_open, + .release = lirc_dev_fop_close, + .llseek = no_llseek, +}; + +static struct lirc_driver driver = { + .name = LIRC_DRIVER_NAME, + .minor = -1, + .code_length = 1, + .sample_rate = 0, + .data = NULL, + .add_to_buf = NULL, + .rbuf = &rbuf, + .set_use_inc = set_use_inc, + .set_use_dec = set_use_dec, + .fops = &lirc_fops, + .dev = NULL, + .owner = THIS_MODULE, +}; + +static const struct of_device_id lirc_rpi_of_match[] = { + { .compatible = "rpi,lirc-rpi", }, + {}, +}; +MODULE_DEVICE_TABLE(of, lirc_rpi_of_match); + +static struct platform_driver lirc_rpi_driver = { + .driver = { + .name = LIRC_DRIVER_NAME, + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(lirc_rpi_of_match), + }, +}; + +static int __init lirc_rpi_init(void) +{ + struct device_node *node; + int result; + + /* Init read buffer. */ + result = lirc_buffer_init(&rbuf, sizeof(int), RBUF_LEN); + if (result < 0) + return -ENOMEM; + + result = platform_driver_register(&lirc_rpi_driver); + if (result) { + printk(KERN_ERR LIRC_DRIVER_NAME + ": lirc register returned %d\n", result); + goto exit_buffer_free; + } + + node = of_find_compatible_node(NULL, NULL, + lirc_rpi_of_match[0].compatible); + + if (node) { + /* DT-enabled */ + lirc_rpi_dev = of_find_device_by_node(node); + WARN_ON(lirc_rpi_dev->dev.of_node != node); + of_node_put(node); + } + else { + lirc_rpi_dev = platform_device_alloc(LIRC_DRIVER_NAME, 0); + if (!lirc_rpi_dev) { + result = -ENOMEM; + goto exit_driver_unregister; + } + + result = platform_device_add(lirc_rpi_dev); + if (result) + goto exit_device_put; + } + + return 0; + + exit_device_put: + platform_device_put(lirc_rpi_dev); + + exit_driver_unregister: + platform_driver_unregister(&lirc_rpi_driver); + + exit_buffer_free: + lirc_buffer_free(&rbuf); + + return result; +} + +static void lirc_rpi_exit(void) +{ + if (!lirc_rpi_dev->dev.of_node) + platform_device_unregister(lirc_rpi_dev); + platform_driver_unregister(&lirc_rpi_driver); + lirc_buffer_free(&rbuf); +} + +static int __init lirc_rpi_init_module(void) +{ + int result; + + result = lirc_rpi_init(); + if (result) + return result; + + result = init_port(); + if (result < 0) + goto exit_rpi; + + driver.features = LIRC_CAN_SET_SEND_DUTY_CYCLE | + LIRC_CAN_SET_SEND_CARRIER | + LIRC_CAN_SEND_PULSE | + LIRC_CAN_REC_MODE2; + + driver.dev = &lirc_rpi_dev->dev; + driver.minor = lirc_register_driver(&driver); + + if (driver.minor < 0) { + printk(KERN_ERR LIRC_DRIVER_NAME + ": device registration failed with %d\n", result); + result = -EIO; + goto exit_rpi; + } + + printk(KERN_INFO LIRC_DRIVER_NAME ": driver registered!\n"); + + return 0; + + exit_rpi: + lirc_rpi_exit(); + + return result; +} + +static void __exit lirc_rpi_exit_module(void) +{ + lirc_unregister_driver(driver.minor); + + gpio_free(gpio_out_pin); + gpio_free(gpio_in_pin); + + lirc_rpi_exit(); + + printk(KERN_INFO LIRC_DRIVER_NAME ": cleaned up module\n"); +} + +module_init(lirc_rpi_init_module); +module_exit(lirc_rpi_exit_module); + +MODULE_DESCRIPTION("Infra-red receiver and blaster driver for Raspberry Pi GPIO."); +MODULE_AUTHOR("Aron Robert Szabo "); +MODULE_AUTHOR("Michael Bishop "); +MODULE_LICENSE("GPL"); + +module_param(gpio_out_pin, int, S_IRUGO); +MODULE_PARM_DESC(gpio_out_pin, "GPIO output/transmitter pin number of the BCM" + " processor. (default 17"); + +module_param(gpio_in_pin, int, S_IRUGO); +MODULE_PARM_DESC(gpio_in_pin, "GPIO input pin number of the BCM processor." + " (default 18"); + +module_param(gpio_in_pull, int, S_IRUGO); +MODULE_PARM_DESC(gpio_in_pull, "GPIO input pin pull configuration." + " (0 = off, 1 = up, 2 = down, default down)"); + +module_param(sense, int, S_IRUGO); +MODULE_PARM_DESC(sense, "Override autodetection of IR receiver circuit" + " (0 = active high, 1 = active low )"); + +module_param(softcarrier, bool, S_IRUGO); +MODULE_PARM_DESC(softcarrier, "Software carrier (0 = off, 1 = on, default on)"); + +module_param(invert, bool, S_IRUGO); +MODULE_PARM_DESC(invert, "Invert output (0 = off, 1 = on, default off"); + +module_param(debug, bool, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(debug, "Enable debugging messages"); --- /dev/null +++ b/include/linux/platform_data/bcm2708.h @@ -0,0 +1,23 @@ +/* + * include/linux/platform_data/bcm2708.h + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * (C) 2014 Julian Scheel + * + */ +#ifndef __BCM2708_H_ +#define __BCM2708_H_ + +typedef enum { + BCM2708_PULL_OFF, + BCM2708_PULL_UP, + BCM2708_PULL_DOWN +} bcm2708_gpio_pull_t; + +extern int bcm2708_gpio_setpull(struct gpio_chip *gc, unsigned offset, + bcm2708_gpio_pull_t value); + +#endif