/* * IR SIR driver, (C) 2000 Milan Pikula * * sir_ir - Device driver for use with SIR (serial infra red) * mode of IrDA on many notebooks. * * 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. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include /* SECTION: Definitions */ #define PULSE '[' /* 9bit * 1s/115200bit in milli seconds = 78.125ms*/ #define TIME_CONST (9000000ul / 115200ul) /* timeout for sequences in jiffies (=5/100s), must be longer than TIME_CONST */ #define SIR_TIMEOUT (HZ * 5 / 100) /* onboard sir ports are typically com3 */ static int io = 0x3e8; static int irq = 4; static int threshold = 3; static DEFINE_SPINLOCK(timer_lock); static struct timer_list timerlist; /* time of last signal change detected */ static ktime_t last; /* time of last UART data ready interrupt */ static ktime_t last_intr_time; static int last_value; static struct rc_dev *rcdev; static struct platform_device *sir_ir_dev; static DEFINE_SPINLOCK(hardware_lock); /* SECTION: Prototypes */ /* Communication with user-space */ static void add_read_queue(int flag, unsigned long val); /* Hardware */ static irqreturn_t sir_interrupt(int irq, void *dev_id); static void send_space(unsigned long len); static void send_pulse(unsigned long len); static int init_hardware(void); static void drop_hardware(void); /* Initialisation */ static inline unsigned int sinp(int offset) { return inb(io + offset); } static inline void soutp(int offset, int value) { outb(value, io + offset); } /* SECTION: Communication with user-space */ static int sir_tx_ir(struct rc_dev *dev, unsigned int *tx_buf, unsigned int count) { unsigned long flags; int i; local_irq_save(flags); for (i = 0; i < count;) { if (tx_buf[i]) send_pulse(tx_buf[i]); i++; if (i >= count) break; if (tx_buf[i]) send_space(tx_buf[i]); i++; } local_irq_restore(flags); return count; } static void add_read_queue(int flag, unsigned long val) { struct ir_raw_event ev = {}; pr_debug("add flag %d with val %lu\n", flag, val); /* * statistically, pulses are ~TIME_CONST/2 too long. we could * maybe make this more exact, but this is good enough */ if (flag) { /* pulse */ if (val > TIME_CONST / 2) val -= TIME_CONST / 2; else /* should not ever happen */ val = 1; ev.pulse = true; } else { val += TIME_CONST / 2; } ev.duration = US_TO_NS(val); ir_raw_event_store_with_filter(rcdev, &ev); } /* SECTION: Hardware */ static void sir_timeout(struct timer_list *unused) { /* * if last received signal was a pulse, but receiving stopped * within the 9 bit frame, we need to finish this pulse and * simulate a signal change to from pulse to space. Otherwise * upper layers will receive two sequences next time. */ unsigned long flags; unsigned long pulse_end; /* avoid interference with interrupt */ spin_lock_irqsave(&timer_lock, flags); if (last_value) { /* clear unread bits in UART and restart */ outb(UART_FCR_CLEAR_RCVR, io + UART_FCR); /* determine 'virtual' pulse end: */ pulse_end = min_t(unsigned long, ktime_us_delta(last, last_intr_time), IR_MAX_DURATION); dev_dbg(&sir_ir_dev->dev, "timeout add %d for %lu usec\n", last_value, pulse_end); add_read_queue(last_value, pulse_end); last_value = 0; last = last_intr_time; } spin_unlock_irqrestore(&timer_lock, flags); ir_raw_event_handle(rcdev); } static irqreturn_t sir_interrupt(int irq, void *dev_id) { unsigned char data; ktime_t curr_time; unsigned long delt; unsigned long deltintr; unsigned long flags; int counter = 0; int iir, lsr; while ((iir = inb(io + UART_IIR) & UART_IIR_ID)) { if (++counter > 256) { dev_err(&sir_ir_dev->dev, "Trapped in interrupt"); break; } switch (iir & UART_IIR_ID) { /* FIXME toto treba preriedit */ case UART_IIR_MSI: (void)inb(io + UART_MSR); break; case UART_IIR_RLSI: case UART_IIR_THRI: (void)inb(io + UART_LSR); break; case UART_IIR_RDI: /* avoid interference with timer */ spin_lock_irqsave(&timer_lock, flags); do { del_timer(&timerlist); data = inb(io + UART_RX); curr_time = ktime_get(); delt = min_t(unsigned long, ktime_us_delta(last, curr_time), IR_MAX_DURATION); deltintr = min_t(unsigned long, ktime_us_delta(last_intr_time, curr_time), IR_MAX_DURATION); dev_dbg(&sir_ir_dev->dev, "t %lu, d %d\n", deltintr, (int)data); /* * if nothing came in last X cycles, * it was gap */ if (deltintr > TIME_CONST * threshold) { if (last_value) { dev_dbg(&sir_ir_dev->dev, "GAP\n"); /* simulate signal change */ add_read_queue(last_value, delt - deltintr); last_value = 0; last = last_intr_time; delt = deltintr; } } data = 1; if (data ^ last_value) { /* * deltintr > 2*TIME_CONST, remember? * the other case is timeout */ add_read_queue(last_value, delt - TIME_CONST); last_value = data; last = curr_time; last = ktime_sub_us(last, TIME_CONST); } last_intr_time = curr_time; if (data) { /* * start timer for end of * sequence detection */ timerlist.expires = jiffies + SIR_TIMEOUT; add_timer(&timerlist); } lsr = inb(io + UART_LSR); } while (lsr & UART_LSR_DR); /* data ready */ spin_unlock_irqrestore(&timer_lock, flags); break; default: break; } } ir_raw_event_handle(rcdev); return IRQ_RETVAL(IRQ_HANDLED); } static void send_space(unsigned long len) { usleep_range(len, len + 25); } static void send_pulse(unsigned long len) { long bytes_out = len / TIME_CONST; if (bytes_out == 0) bytes_out++; while (bytes_out--) { outb(PULSE, io + UART_TX); /* FIXME treba seriozne cakanie z char/serial.c */ while (!(inb(io + UART_LSR) & UART_LSR_THRE)) ; } } static int init_hardware(void) { u8 scratch, scratch2, scratch3; unsigned long flags; spin_lock_irqsave(&hardware_lock, flags); /* * This is a simple port existence test, borrowed from the autoconfig * function in drivers/tty/serial/8250/8250_port.c */ scratch = sinp(UART_IER); soutp(UART_IER, 0); #ifdef __i386__ outb(0xff, 0x080); #endif scratch2 = sinp(UART_IER) & 0x0f; soutp(UART_IER, 0x0f); #ifdef __i386__ outb(0x00, 0x080); #endif scratch3 = sinp(UART_IER) & 0x0f; soutp(UART_IER, scratch); if (scratch2 != 0 || scratch3 != 0x0f) { /* we fail, there's nothing here */ spin_unlock_irqrestore(&hardware_lock, flags); pr_err("port existence test failed, cannot continue\n"); return -ENODEV; } /* reset UART */ outb(0, io + UART_MCR); outb(0, io + UART_IER); /* init UART */ /* set DLAB, speed = 115200 */ outb(UART_LCR_DLAB | UART_LCR_WLEN7, io + UART_LCR); outb(1, io + UART_DLL); outb(0, io + UART_DLM); /* 7N1+start = 9 bits at 115200 ~ 3 bits at 44000 */ outb(UART_LCR_WLEN7, io + UART_LCR); /* FIFO operation */ outb(UART_FCR_ENABLE_FIFO, io + UART_FCR); /* interrupts */ /* outb(UART_IER_RLSI|UART_IER_RDI|UART_IER_THRI, io + UART_IER); */ outb(UART_IER_RDI, io + UART_IER); /* turn on UART */ outb(UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2, io + UART_MCR); spin_unlock_irqrestore(&hardware_lock, flags); return 0; } static void drop_hardware(void) { unsigned long flags; spin_lock_irqsave(&hardware_lock, flags); /* turn off interrupts */ outb(0, io + UART_IER); spin_unlock_irqrestore(&hardware_lock, flags); } /* SECTION: Initialisation */ static int sir_ir_probe(struct platform_device *dev) { int retval; rcdev = devm_rc_allocate_device(&sir_ir_dev->dev, RC_DRIVER_IR_RAW); if (!rcdev) return -ENOMEM; rcdev->device_name = "SIR IrDA port"; rcdev->input_phys = KBUILD_MODNAME "/input0"; rcdev->input_id.bustype = BUS_HOST; rcdev->input_id.vendor = 0x0001; rcdev->input_id.product = 0x0001; rcdev->input_id.version = 0x0100; rcdev->tx_ir = sir_tx_ir; rcdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER; rcdev->driver_name = KBUILD_MODNAME; rcdev->map_name = RC_MAP_RC6_MCE; rcdev->timeout = IR_DEFAULT_TIMEOUT; rcdev->dev.parent = &sir_ir_dev->dev; timer_setup(&timerlist, sir_timeout, 0); /* get I/O port access and IRQ line */ if (!devm_request_region(&sir_ir_dev->dev, io, 8, KBUILD_MODNAME)) { pr_err("i/o port 0x%.4x already in use.\n", io); return -EBUSY; } retval = devm_request_irq(&sir_ir_dev->dev, irq, sir_interrupt, 0, KBUILD_MODNAME, NULL); if (retval < 0) { pr_err("IRQ %d already in use.\n", irq); return retval; } retval = init_hardware(); if (retval) { del_timer_sync(&timerlist); return retval; } pr_info("I/O port 0x%.4x, IRQ %d.\n", io, irq); retval = devm_rc_register_device(&sir_ir_dev->dev, rcdev); if (retval < 0) return retval; return 0; } static int sir_ir_remove(struct platform_device *dev) { drop_hardware(); del_timer_sync(&timerlist); return 0; } static struct platform_driver sir_ir_driver = { .probe = sir_ir_probe, .remove = sir_ir_remove, .driver = { .name = "sir_ir", }, }; static int __init sir_ir_init(void) { int retval; retval = platform_driver_register(&sir_ir_driver); if (retval) return retval; sir_ir_dev = platform_device_alloc("sir_ir", 0); if (!sir_ir_dev) { retval = -ENOMEM; goto pdev_alloc_fail; } retval = platform_device_add(sir_ir_dev); if (retval) goto pdev_add_fail; return 0; pdev_add_fail: platform_device_put(sir_ir_dev); pdev_alloc_fail: platform_driver_unregister(&sir_ir_driver); return retval; } static void __exit sir_ir_exit(void) { platform_device_unregister(sir_ir_dev); platform_driver_unregister(&sir_ir_driver); } module_init(sir_ir_init); module_exit(sir_ir_exit); MODULE_DESCRIPTION("Infrared receiver driver for SIR type serial ports"); MODULE_AUTHOR("Milan Pikula"); MODULE_LICENSE("GPL"); module_param_hw(io, int, ioport, 0444); MODULE_PARM_DESC(io, "I/O address base (0x3f8 or 0x2f8)"); module_param_hw(irq, int, irq, 0444); MODULE_PARM_DESC(irq, "Interrupt (4 or 3)"); module_param(threshold, int, 0444); MODULE_PARM_DESC(threshold, "space detection threshold (3)");