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Diffstat (limited to 'drivers/media/rc/sir_ir.c')
-rw-r--r--drivers/media/rc/sir_ir.c442
1 files changed, 442 insertions, 0 deletions
diff --git a/drivers/media/rc/sir_ir.c b/drivers/media/rc/sir_ir.c
new file mode 100644
index 000000000..9ee2c9196
--- /dev/null
+++ b/drivers/media/rc/sir_ir.c
@@ -0,0 +1,442 @@
+/*
+ * IR SIR driver, (C) 2000 Milan Pikula <www@fornax.sk>
+ *
+ * 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 <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/serial_reg.h>
+#include <linux/ktime.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+
+#include <media/rc-core.h>
+
+/* 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)
+{
+ DEFINE_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)");
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-01 03:29:45 +0000