^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Copyright (C) 2017 Sean Young <sean@mess.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/gpio/consumer.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/delay.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/of.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <media/rc-core.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #define DRIVER_NAME "gpio-ir-tx"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #define DEVICE_NAME "GPIO IR Bit Banging Transmitter"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) struct gpio_ir {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) struct gpio_desc *gpio;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) unsigned int carrier;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) unsigned int duty_cycle;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) static const struct of_device_id gpio_ir_tx_of_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) { .compatible = "gpio-ir-tx", },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) { },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) MODULE_DEVICE_TABLE(of, gpio_ir_tx_of_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) static int gpio_ir_tx_set_duty_cycle(struct rc_dev *dev, u32 duty_cycle)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) struct gpio_ir *gpio_ir = dev->priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) gpio_ir->duty_cycle = duty_cycle;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) static int gpio_ir_tx_set_carrier(struct rc_dev *dev, u32 carrier)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) struct gpio_ir *gpio_ir = dev->priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) if (carrier > 500000)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) gpio_ir->carrier = carrier;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) static void delay_until(ktime_t until)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) * delta should never exceed 0.5 seconds (IR_MAX_DURATION) and on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) * m68k ndelay(s64) does not compile; so use s32 rather than s64.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) s32 delta;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) while (true) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) delta = ktime_us_delta(until, ktime_get());
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) if (delta <= 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) /* udelay more than 1ms may not work */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) delta = min(delta, 1000);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) udelay(delta);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) static void gpio_ir_tx_unmodulated(struct gpio_ir *gpio_ir, uint *txbuf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) uint count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) ktime_t edge;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) local_irq_disable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) edge = ktime_get();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) for (i = 0; i < count; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) gpiod_set_value(gpio_ir->gpio, !(i % 2));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) edge = ktime_add_us(edge, txbuf[i]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) delay_until(edge);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) gpiod_set_value(gpio_ir->gpio, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) static void gpio_ir_tx_modulated(struct gpio_ir *gpio_ir, uint *txbuf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) uint count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) ktime_t edge;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) * delta should never exceed 0.5 seconds (IR_MAX_DURATION) and on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) * m68k ndelay(s64) does not compile; so use s32 rather than s64.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) s32 delta;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) unsigned int pulse, space;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) /* Ensure the dividend fits into 32 bit */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) pulse = DIV_ROUND_CLOSEST(gpio_ir->duty_cycle * (NSEC_PER_SEC / 100),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) gpio_ir->carrier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) space = DIV_ROUND_CLOSEST((100 - gpio_ir->duty_cycle) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) (NSEC_PER_SEC / 100), gpio_ir->carrier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) local_irq_disable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) edge = ktime_get();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) for (i = 0; i < count; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) if (i % 2) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) // space
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) edge = ktime_add_us(edge, txbuf[i]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) delay_until(edge);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) // pulse
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) ktime_t last = ktime_add_us(edge, txbuf[i]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) while (ktime_before(ktime_get(), last)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) gpiod_set_value(gpio_ir->gpio, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) edge = ktime_add_ns(edge, pulse);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) delta = ktime_to_ns(ktime_sub(edge,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) ktime_get()));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) if (delta > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) ndelay(delta);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) gpiod_set_value(gpio_ir->gpio, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) edge = ktime_add_ns(edge, space);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) delta = ktime_to_ns(ktime_sub(edge,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) ktime_get()));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) if (delta > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) ndelay(delta);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) edge = last;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) static int gpio_ir_tx(struct rc_dev *dev, unsigned int *txbuf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) unsigned int count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) struct gpio_ir *gpio_ir = dev->priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) local_irq_save(flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) if (gpio_ir->carrier)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) gpio_ir_tx_modulated(gpio_ir, txbuf, count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) gpio_ir_tx_unmodulated(gpio_ir, txbuf, count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) local_irq_restore(flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) static int gpio_ir_tx_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) struct gpio_ir *gpio_ir;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) struct rc_dev *rcdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) int rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) gpio_ir = devm_kmalloc(&pdev->dev, sizeof(*gpio_ir), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) if (!gpio_ir)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) rcdev = devm_rc_allocate_device(&pdev->dev, RC_DRIVER_IR_RAW_TX);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) if (!rcdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) gpio_ir->gpio = devm_gpiod_get(&pdev->dev, NULL, GPIOD_OUT_LOW);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) if (IS_ERR(gpio_ir->gpio)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) if (PTR_ERR(gpio_ir->gpio) != -EPROBE_DEFER)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) dev_err(&pdev->dev, "Failed to get gpio (%ld)\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) PTR_ERR(gpio_ir->gpio));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) return PTR_ERR(gpio_ir->gpio);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) rcdev->priv = gpio_ir;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) rcdev->driver_name = DRIVER_NAME;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) rcdev->device_name = DEVICE_NAME;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) rcdev->tx_ir = gpio_ir_tx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) rcdev->s_tx_duty_cycle = gpio_ir_tx_set_duty_cycle;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) rcdev->s_tx_carrier = gpio_ir_tx_set_carrier;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) gpio_ir->carrier = 38000;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) gpio_ir->duty_cycle = 50;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) rc = devm_rc_register_device(&pdev->dev, rcdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) if (rc < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) dev_err(&pdev->dev, "failed to register rc device\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) static struct platform_driver gpio_ir_tx_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) .probe = gpio_ir_tx_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) .name = DRIVER_NAME,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) .of_match_table = of_match_ptr(gpio_ir_tx_of_match),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) module_platform_driver(gpio_ir_tx_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) MODULE_DESCRIPTION("GPIO IR Bit Banging Transmitter");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) MODULE_AUTHOR("Sean Young <sean@mess.org>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) MODULE_LICENSE("GPL");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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