2 * linux/drivers/net/irda/sa1100_ir.c
4 * Copyright (C) 2000-2001 Russell King
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 * Infra-red driver for the StrongARM SA1100 embedded microprocessor
12 * Note that we don't have to worry about the SA1111's DMA bugs in here,
13 * so we use the straight forward dma_map_* functions with a null pointer.
15 * This driver takes one kernel command line parameter, sa1100ir=, with
16 * the following options:
17 * max_rate:baudrate - set the maximum baud rate
18 * power_leve:level - set the transmitter power level
19 * tx_lpm:0|1 - set transmit low power mode
21 #include <linux/module.h>
22 #include <linux/moduleparam.h>
23 #include <linux/types.h>
24 #include <linux/init.h>
25 #include <linux/errno.h>
26 #include <linux/netdevice.h>
27 #include <linux/slab.h>
28 #include <linux/rtnetlink.h>
29 #include <linux/interrupt.h>
30 #include <linux/delay.h>
31 #include <linux/platform_device.h>
32 #include <linux/dma-mapping.h>
34 #include <net/irda/irda.h>
35 #include <net/irda/wrapper.h>
36 #include <net/irda/irda_device.h>
40 #include <mach/hardware.h>
41 #include <asm/mach/irda.h>
43 static int power_level = 3;
45 static int max_rate = 4000000;
56 struct sk_buff *txskb;
57 struct sk_buff *rxskb;
63 struct net_device_stats stats;
65 struct irda_platform_data *pdata;
66 struct irlap_cb *irlap;
73 #define IS_FIR(si) ((si)->speed >= 4000000)
75 #define HPSIR_MAX_RXLEN 2047
78 * Allocate and map the receive buffer, unless it is already allocated.
80 static int sa1100_irda_rx_alloc(struct sa1100_irda *si)
85 si->rxskb = alloc_skb(HPSIR_MAX_RXLEN + 1, GFP_ATOMIC);
88 printk(KERN_ERR "sa1100_ir: out of memory for RX SKB\n");
93 * Align any IP headers that may be contained
96 skb_reserve(si->rxskb, 1);
98 si->rxbuf_dma = dma_map_single(si->dev, si->rxskb->data,
105 * We want to get here as soon as possible, and get the receiver setup.
106 * We use the existing buffer.
108 static void sa1100_irda_rx_dma_start(struct sa1100_irda *si)
111 printk(KERN_ERR "sa1100_ir: rx buffer went missing\n");
116 * First empty receive FIFO
118 Ser2HSCR0 = si->hscr0 | HSCR0_HSSP;
121 * Enable the DMA, receiver and receive interrupt.
123 sa1100_clear_dma(si->rxdma);
124 sa1100_start_dma(si->rxdma, si->rxbuf_dma, HPSIR_MAX_RXLEN);
125 Ser2HSCR0 = si->hscr0 | HSCR0_HSSP | HSCR0_RXE;
129 * Set the IrDA communications speed.
131 static int sa1100_irda_set_speed(struct sa1100_irda *si, int speed)
134 int brd, ret = -EINVAL;
137 case 9600: case 19200: case 38400:
138 case 57600: case 115200:
139 brd = 3686400 / (16 * speed) - 1;
142 * Stop the receive DMA.
145 sa1100_stop_dma(si->rxdma);
147 local_irq_save(flags);
150 Ser2HSCR0 = HSCR0_UART;
152 Ser2UTCR1 = brd >> 8;
156 * Clear status register
158 Ser2UTSR0 = UTSR0_REB | UTSR0_RBB | UTSR0_RID;
159 Ser2UTCR3 = UTCR3_RIE | UTCR3_RXE | UTCR3_TXE;
161 if (si->pdata->set_speed)
162 si->pdata->set_speed(si->dev, speed);
166 local_irq_restore(flags);
171 local_irq_save(flags);
176 Ser2HSCR0 = si->hscr0 | HSCR0_HSSP;
181 if (si->pdata->set_speed)
182 si->pdata->set_speed(si->dev, speed);
184 sa1100_irda_rx_alloc(si);
185 sa1100_irda_rx_dma_start(si);
187 local_irq_restore(flags);
199 * Control the power state of the IrDA transmitter.
202 * 1 - short range, lowest power
203 * 2 - medium range, medium power
204 * 3 - maximum range, high power
206 * Currently, only assabet is known to support this.
209 __sa1100_irda_set_power(struct sa1100_irda *si, unsigned int state)
212 if (si->pdata->set_power)
213 ret = si->pdata->set_power(si->dev, state);
218 sa1100_set_power(struct sa1100_irda *si, unsigned int state)
222 ret = __sa1100_irda_set_power(si, state);
229 static int sa1100_irda_startup(struct sa1100_irda *si)
234 * Ensure that the ports for this device are setup correctly.
236 if (si->pdata->startup)
237 si->pdata->startup(si->dev);
240 * Configure PPC for IRDA - we want to drive TXD2 low.
241 * We also want to drive this pin low during sleep.
248 * Enable HP-SIR modulation, and ensure that the port is disabled.
251 Ser2HSCR0 = HSCR0_UART;
252 Ser2UTCR4 = si->utcr4;
253 Ser2UTCR0 = UTCR0_8BitData;
254 Ser2HSCR2 = HSCR2_TrDataH | HSCR2_RcDataL;
257 * Clear status register
259 Ser2UTSR0 = UTSR0_REB | UTSR0_RBB | UTSR0_RID;
261 ret = sa1100_irda_set_speed(si, si->speed = 9600);
266 if (si->pdata->shutdown)
267 si->pdata->shutdown(si->dev);
273 static void sa1100_irda_shutdown(struct sa1100_irda *si)
276 * Stop all DMA activity.
278 sa1100_stop_dma(si->rxdma);
279 sa1100_stop_dma(si->txdma);
281 /* Disable the port. */
285 if (si->pdata->shutdown)
286 si->pdata->shutdown(si->dev);
291 * Suspend the IrDA interface.
293 static int sa1100_irda_suspend(struct platform_device *pdev, pm_message_t state)
295 struct net_device *dev = platform_get_drvdata(pdev);
296 struct sa1100_irda *si;
304 * Stop the transmit queue
306 netif_device_detach(dev);
307 disable_irq(dev->irq);
308 sa1100_irda_shutdown(si);
309 __sa1100_irda_set_power(si, 0);
316 * Resume the IrDA interface.
318 static int sa1100_irda_resume(struct platform_device *pdev)
320 struct net_device *dev = platform_get_drvdata(pdev);
321 struct sa1100_irda *si;
329 * If we missed a speed change, initialise at the new speed
330 * directly. It is debatable whether this is actually
331 * required, but in the interests of continuing from where
332 * we left off it is desireable. The converse argument is
333 * that we should re-negotiate at 9600 baud again.
336 si->speed = si->newspeed;
340 sa1100_irda_startup(si);
341 __sa1100_irda_set_power(si, si->power);
342 enable_irq(dev->irq);
345 * This automatically wakes up the queue
347 netif_device_attach(dev);
353 #define sa1100_irda_suspend NULL
354 #define sa1100_irda_resume NULL
358 * HP-SIR format interrupt service routines.
360 static void sa1100_irda_hpsir_irq(struct net_device *dev)
362 struct sa1100_irda *si = dev->priv;
368 * Deal with any receive errors first. The bytes in error may be
369 * the only bytes in the receive FIFO, so we do this first.
371 while (status & UTSR0_EIF) {
377 if (stat & (UTSR1_FRE | UTSR1_ROR)) {
378 si->stats.rx_errors++;
379 if (stat & UTSR1_FRE)
380 si->stats.rx_frame_errors++;
381 if (stat & UTSR1_ROR)
382 si->stats.rx_fifo_errors++;
384 async_unwrap_char(dev, &si->stats, &si->rx_buff, data);
390 * We must clear certain bits.
392 Ser2UTSR0 = status & (UTSR0_RID | UTSR0_RBB | UTSR0_REB);
394 if (status & UTSR0_RFS) {
396 * There are at least 4 bytes in the FIFO. Read 3 bytes
397 * and leave the rest to the block below.
399 async_unwrap_char(dev, &si->stats, &si->rx_buff, Ser2UTDR);
400 async_unwrap_char(dev, &si->stats, &si->rx_buff, Ser2UTDR);
401 async_unwrap_char(dev, &si->stats, &si->rx_buff, Ser2UTDR);
404 if (status & (UTSR0_RFS | UTSR0_RID)) {
406 * Fifo contains more than 1 character.
409 async_unwrap_char(dev, &si->stats, &si->rx_buff,
411 } while (Ser2UTSR1 & UTSR1_RNE);
413 dev->last_rx = jiffies;
416 if (status & UTSR0_TFS && si->tx_buff.len) {
418 * Transmitter FIFO is not full
421 Ser2UTDR = *si->tx_buff.data++;
422 si->tx_buff.len -= 1;
423 } while (Ser2UTSR1 & UTSR1_TNF && si->tx_buff.len);
425 if (si->tx_buff.len == 0) {
426 si->stats.tx_packets++;
427 si->stats.tx_bytes += si->tx_buff.data -
431 * We need to ensure that the transmitter has
436 while (Ser2UTSR1 & UTSR1_TBY);
439 * Ok, we've finished transmitting. Now enable
440 * the receiver. Sometimes we get a receive IRQ
441 * immediately after a transmit...
443 Ser2UTSR0 = UTSR0_REB | UTSR0_RBB | UTSR0_RID;
444 Ser2UTCR3 = UTCR3_RIE | UTCR3_RXE | UTCR3_TXE;
447 sa1100_irda_set_speed(si, si->newspeed);
452 netif_wake_queue(dev);
457 static void sa1100_irda_fir_error(struct sa1100_irda *si, struct net_device *dev)
459 struct sk_buff *skb = si->rxskb;
461 unsigned int len, stat, data;
464 printk(KERN_ERR "sa1100_ir: SKB is NULL!\n");
469 * Get the current data position.
471 dma_addr = sa1100_get_dma_pos(si->rxdma);
472 len = dma_addr - si->rxbuf_dma;
473 if (len > HPSIR_MAX_RXLEN)
474 len = HPSIR_MAX_RXLEN;
475 dma_unmap_single(si->dev, si->rxbuf_dma, len, DMA_FROM_DEVICE);
479 * Read Status, and then Data.
485 if (stat & (HSSR1_CRE | HSSR1_ROR)) {
486 si->stats.rx_errors++;
487 if (stat & HSSR1_CRE)
488 si->stats.rx_crc_errors++;
489 if (stat & HSSR1_ROR)
490 si->stats.rx_frame_errors++;
492 skb->data[len++] = data;
495 * If we hit the end of frame, there's
496 * no point in continuing.
498 if (stat & HSSR1_EOF)
500 } while (Ser2HSSR0 & HSSR0_EIF);
502 if (stat & HSSR1_EOF) {
507 skb_reset_mac_header(skb);
508 skb->protocol = htons(ETH_P_IRDA);
509 si->stats.rx_packets++;
510 si->stats.rx_bytes += len;
513 * Before we pass the buffer up, allocate a new one.
515 sa1100_irda_rx_alloc(si);
518 dev->last_rx = jiffies;
523 si->rxbuf_dma = dma_map_single(si->dev, si->rxskb->data,
530 * FIR format interrupt service routine. We only have to
531 * handle RX events; transmit events go via the TX DMA handler.
533 * No matter what, we disable RX, process, and the restart RX.
535 static void sa1100_irda_fir_irq(struct net_device *dev)
537 struct sa1100_irda *si = dev->priv;
542 sa1100_stop_dma(si->rxdma);
545 * Framing error - we throw away the packet completely.
546 * Clearing RXE flushes the error conditions and data
549 if (Ser2HSSR0 & (HSSR0_FRE | HSSR0_RAB)) {
550 si->stats.rx_errors++;
552 if (Ser2HSSR0 & HSSR0_FRE)
553 si->stats.rx_frame_errors++;
556 * Clear out the DMA...
558 Ser2HSCR0 = si->hscr0 | HSCR0_HSSP;
561 * Clear selected status bits now, so we
562 * don't miss them next time around.
564 Ser2HSSR0 = HSSR0_FRE | HSSR0_RAB;
568 * Deal with any receive errors. The any of the lowest
569 * 8 bytes in the FIFO may contain an error. We must read
570 * them one by one. The "error" could even be the end of
573 if (Ser2HSSR0 & HSSR0_EIF)
574 sa1100_irda_fir_error(si, dev);
577 * No matter what happens, we must restart reception.
579 sa1100_irda_rx_dma_start(si);
582 static irqreturn_t sa1100_irda_irq(int irq, void *dev_id)
584 struct net_device *dev = dev_id;
585 if (IS_FIR(((struct sa1100_irda *)dev->priv)))
586 sa1100_irda_fir_irq(dev);
588 sa1100_irda_hpsir_irq(dev);
593 * TX DMA completion handler.
595 static void sa1100_irda_txdma_irq(void *id)
597 struct net_device *dev = id;
598 struct sa1100_irda *si = dev->priv;
599 struct sk_buff *skb = si->txskb;
604 * Wait for the transmission to complete. Unfortunately,
605 * the hardware doesn't give us an interrupt to indicate
610 while (!(Ser2HSSR0 & HSSR0_TUR) || Ser2HSSR1 & HSSR1_TBY);
613 * Clear the transmit underrun bit.
615 Ser2HSSR0 = HSSR0_TUR;
618 * Do we need to change speed? Note that we're lazy
619 * here - we don't free the old rxskb. We don't need
620 * to allocate a buffer either.
623 sa1100_irda_set_speed(si, si->newspeed);
628 * Start reception. This disables the transmitter for
629 * us. This will be using the existing RX buffer.
631 sa1100_irda_rx_dma_start(si);
634 * Account and free the packet.
637 dma_unmap_single(si->dev, si->txbuf_dma, skb->len, DMA_TO_DEVICE);
638 si->stats.tx_packets ++;
639 si->stats.tx_bytes += skb->len;
640 dev_kfree_skb_irq(skb);
644 * Make sure that the TX queue is available for sending
645 * (for retries). TX has priority over RX at all times.
647 netif_wake_queue(dev);
650 static int sa1100_irda_hard_xmit(struct sk_buff *skb, struct net_device *dev)
652 struct sa1100_irda *si = dev->priv;
653 int speed = irda_get_next_speed(skb);
656 * Does this packet contain a request to change the interface
657 * speed? If so, remember it until we complete the transmission
660 if (speed != si->speed && speed != -1)
661 si->newspeed = speed;
664 * If this is an empty frame, we can bypass a lot.
669 sa1100_irda_set_speed(si, speed);
676 netif_stop_queue(dev);
678 si->tx_buff.data = si->tx_buff.head;
679 si->tx_buff.len = async_wrap_skb(skb, si->tx_buff.data,
680 si->tx_buff.truesize);
683 * Set the transmit interrupt enable. This will fire
684 * off an interrupt immediately. Note that we disable
685 * the receiver so we won't get spurious characteres
688 Ser2UTCR3 = UTCR3_TIE | UTCR3_TXE;
692 int mtt = irda_get_mtt(skb);
695 * We must not be transmitting...
699 netif_stop_queue(dev);
702 si->txbuf_dma = dma_map_single(si->dev, skb->data,
703 skb->len, DMA_TO_DEVICE);
705 sa1100_start_dma(si->txdma, si->txbuf_dma, skb->len);
708 * If we have a mean turn-around time, impose the specified
709 * specified delay. We could shorten this by timing from
710 * the point we received the packet.
715 Ser2HSCR0 = si->hscr0 | HSCR0_HSSP | HSCR0_TXE;
718 dev->trans_start = jiffies;
724 sa1100_irda_ioctl(struct net_device *dev, struct ifreq *ifreq, int cmd)
726 struct if_irda_req *rq = (struct if_irda_req *)ifreq;
727 struct sa1100_irda *si = dev->priv;
728 int ret = -EOPNOTSUPP;
732 if (capable(CAP_NET_ADMIN)) {
734 * We are unable to set the speed if the
735 * device is not running.
738 ret = sa1100_irda_set_speed(si,
741 printk("sa1100_irda_ioctl: SIOCSBANDWIDTH: !netif_running\n");
749 if (capable(CAP_NET_ADMIN)) {
750 irda_device_set_media_busy(dev, TRUE);
756 rq->ifr_receiving = IS_FIR(si) ? 0
757 : si->rx_buff.state != OUTSIDE_FRAME;
767 static struct net_device_stats *sa1100_irda_stats(struct net_device *dev)
769 struct sa1100_irda *si = dev->priv;
773 static int sa1100_irda_start(struct net_device *dev)
775 struct sa1100_irda *si = dev->priv;
780 err = request_irq(dev->irq, sa1100_irda_irq, 0, dev->name, dev);
784 err = sa1100_request_dma(DMA_Ser2HSSPRd, "IrDA receive",
785 NULL, NULL, &si->rxdma);
789 err = sa1100_request_dma(DMA_Ser2HSSPWr, "IrDA transmit",
790 sa1100_irda_txdma_irq, dev, &si->txdma);
795 * The interrupt must remain disabled for now.
797 disable_irq(dev->irq);
800 * Setup the serial port for the specified speed.
802 err = sa1100_irda_startup(si);
807 * Open a new IrLAP layer instance.
809 si->irlap = irlap_open(dev, &si->qos, "sa1100");
815 * Now enable the interrupt and start the queue
818 sa1100_set_power(si, power_level); /* low power mode */
819 enable_irq(dev->irq);
820 netif_start_queue(dev);
825 sa1100_irda_shutdown(si);
827 sa1100_free_dma(si->txdma);
829 sa1100_free_dma(si->rxdma);
831 free_irq(dev->irq, dev);
836 static int sa1100_irda_stop(struct net_device *dev)
838 struct sa1100_irda *si = dev->priv;
840 disable_irq(dev->irq);
841 sa1100_irda_shutdown(si);
844 * If we have been doing DMA receive, make sure we
845 * tidy that up cleanly.
848 dma_unmap_single(si->dev, si->rxbuf_dma, HPSIR_MAX_RXLEN,
850 dev_kfree_skb(si->rxskb);
856 irlap_close(si->irlap);
860 netif_stop_queue(dev);
866 sa1100_free_dma(si->txdma);
867 sa1100_free_dma(si->rxdma);
868 free_irq(dev->irq, dev);
870 sa1100_set_power(si, 0);
875 static int sa1100_irda_init_iobuf(iobuff_t *io, int size)
877 io->head = kmalloc(size, GFP_KERNEL | GFP_DMA);
878 if (io->head != NULL) {
880 io->in_frame = FALSE;
881 io->state = OUTSIDE_FRAME;
884 return io->head ? 0 : -ENOMEM;
887 static int sa1100_irda_probe(struct platform_device *pdev)
889 struct net_device *dev;
890 struct sa1100_irda *si;
891 unsigned int baudrate_mask;
894 if (!pdev->dev.platform_data)
897 err = request_mem_region(__PREG(Ser2UTCR0), 0x24, "IrDA") ? 0 : -EBUSY;
900 err = request_mem_region(__PREG(Ser2HSCR0), 0x1c, "IrDA") ? 0 : -EBUSY;
903 err = request_mem_region(__PREG(Ser2HSCR2), 0x04, "IrDA") ? 0 : -EBUSY;
907 dev = alloc_irdadev(sizeof(struct sa1100_irda));
912 si->dev = &pdev->dev;
913 si->pdata = pdev->dev.platform_data;
916 * Initialise the HP-SIR buffers
918 err = sa1100_irda_init_iobuf(&si->rx_buff, 14384);
921 err = sa1100_irda_init_iobuf(&si->tx_buff, 4000);
925 dev->hard_start_xmit = sa1100_irda_hard_xmit;
926 dev->open = sa1100_irda_start;
927 dev->stop = sa1100_irda_stop;
928 dev->do_ioctl = sa1100_irda_ioctl;
929 dev->get_stats = sa1100_irda_stats;
930 dev->irq = IRQ_Ser2ICP;
932 irda_init_max_qos_capabilies(&si->qos);
935 * We support original IRDA up to 115k2. (we don't currently
936 * support 4Mbps). Min Turn Time set to 1ms or greater.
938 baudrate_mask = IR_9600;
941 case 4000000: baudrate_mask |= IR_4000000 << 8;
942 case 115200: baudrate_mask |= IR_115200;
943 case 57600: baudrate_mask |= IR_57600;
944 case 38400: baudrate_mask |= IR_38400;
945 case 19200: baudrate_mask |= IR_19200;
948 si->qos.baud_rate.bits &= baudrate_mask;
949 si->qos.min_turn_time.bits = 7;
951 irda_qos_bits_to_value(&si->qos);
953 si->utcr4 = UTCR4_HPSIR;
955 si->utcr4 |= UTCR4_Z1_6us;
958 * Initially enable HP-SIR modulation, and ensure that the port
962 Ser2UTCR4 = si->utcr4;
963 Ser2HSCR0 = HSCR0_UART;
965 err = register_netdev(dev);
967 platform_set_drvdata(pdev, dev);
971 kfree(si->tx_buff.head);
972 kfree(si->rx_buff.head);
975 release_mem_region(__PREG(Ser2HSCR2), 0x04);
977 release_mem_region(__PREG(Ser2HSCR0), 0x1c);
979 release_mem_region(__PREG(Ser2UTCR0), 0x24);
985 static int sa1100_irda_remove(struct platform_device *pdev)
987 struct net_device *dev = platform_get_drvdata(pdev);
990 struct sa1100_irda *si = dev->priv;
991 unregister_netdev(dev);
992 kfree(si->tx_buff.head);
993 kfree(si->rx_buff.head);
997 release_mem_region(__PREG(Ser2HSCR2), 0x04);
998 release_mem_region(__PREG(Ser2HSCR0), 0x1c);
999 release_mem_region(__PREG(Ser2UTCR0), 0x24);
1004 static struct platform_driver sa1100ir_driver = {
1005 .probe = sa1100_irda_probe,
1006 .remove = sa1100_irda_remove,
1007 .suspend = sa1100_irda_suspend,
1008 .resume = sa1100_irda_resume,
1010 .name = "sa11x0-ir",
1011 .owner = THIS_MODULE,
1015 static int __init sa1100_irda_init(void)
1018 * Limit power level a sensible range.
1020 if (power_level < 1)
1022 if (power_level > 3)
1025 return platform_driver_register(&sa1100ir_driver);
1028 static void __exit sa1100_irda_exit(void)
1030 platform_driver_unregister(&sa1100ir_driver);
1033 module_init(sa1100_irda_init);
1034 module_exit(sa1100_irda_exit);
1035 module_param(power_level, int, 0);
1036 module_param(tx_lpm, int, 0);
1037 module_param(max_rate, int, 0);
1039 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
1040 MODULE_DESCRIPTION("StrongARM SA1100 IrDA driver");
1041 MODULE_LICENSE("GPL");
1042 MODULE_PARM_DESC(power_level, "IrDA power level, 1 (low) to 3 (high)");
1043 MODULE_PARM_DESC(tx_lpm, "Enable transmitter low power (1.6us) mode");
1044 MODULE_PARM_DESC(max_rate, "Maximum baud rate (4000000, 115200, 57600, 38400, 19200, 9600)");
1045 MODULE_ALIAS("platform:sa11x0-ir");