/* * Copyright (C) 2008 Sebastian Haas (initial chardev implementation) * Copyright (C) 2010 Markus Plessing <plessing@ems-wuensche.com> * Rework for mainline by Oliver Hartkopp <socketcan@hartkopp.net> * * This program is free software; you can redistribute it and/or modify * it under the terms of the version 2 of the GNU General Public License * as published by the Free Software Foundation * * 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. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/interrupt.h> #include <linux/netdevice.h> #include <linux/delay.h> #include <linux/io.h> #include <pcmcia/cistpl.h> #include <pcmcia/ds.h> #include <linux/can.h> #include <linux/can/dev.h> #include "sja1000.h" #define DRV_NAME "ems_pcmcia" MODULE_AUTHOR("Markus Plessing <plessing@ems-wuensche.com>"); MODULE_DESCRIPTION("Socket-CAN driver for EMS CPC-CARD cards"); MODULE_SUPPORTED_DEVICE("EMS CPC-CARD CAN card"); MODULE_LICENSE("GPL v2"); #define EMS_PCMCIA_MAX_CHAN 2 struct ems_pcmcia_card { int channels; struct pcmcia_device *pcmcia_dev; struct net_device *net_dev[EMS_PCMCIA_MAX_CHAN]; void __iomem *base_addr; }; #define EMS_PCMCIA_CAN_CLOCK (16000000 / 2) /* * The board configuration is probably following: * RX1 is connected to ground. * TX1 is not connected. * CLKO is not connected. * Setting the OCR register to 0xDA is a good idea. * This means normal output mode , push-pull and the correct polarity. */ #define EMS_PCMCIA_OCR (OCR_TX0_PUSHPULL | OCR_TX1_PUSHPULL) /* * In the CDR register, you should set CBP to 1. * You will probably also want to set the clock divider value to 7 * (meaning direct oscillator output) because the second SJA1000 chip * is driven by the first one CLKOUT output. */ #define EMS_PCMCIA_CDR (CDR_CBP | CDR_CLKOUT_MASK) #define EMS_PCMCIA_MEM_SIZE 4096 /* Size of the remapped io-memory */ #define EMS_PCMCIA_CAN_BASE_OFFSET 0x100 /* Offset where controllers starts */ #define EMS_PCMCIA_CAN_CTRL_SIZE 0x80 /* Memory size for each controller */ #define EMS_CMD_RESET 0x00 /* Perform a reset of the card */ #define EMS_CMD_MAP 0x03 /* Map CAN controllers into card' memory */ #define EMS_CMD_UMAP 0x02 /* Unmap CAN controllers from card' memory */ static struct pcmcia_device_id ems_pcmcia_tbl[] = { PCMCIA_DEVICE_PROD_ID123("EMS_T_W", "CPC-Card", "V2.0", 0xeab1ea23, 0xa338573f, 0xe4575800), PCMCIA_DEVICE_NULL, }; MODULE_DEVICE_TABLE(pcmcia, ems_pcmcia_tbl); static u8 ems_pcmcia_read_reg(const struct sja1000_priv *priv, int port) { return readb(priv->reg_base + port); } static void ems_pcmcia_write_reg(const struct sja1000_priv *priv, int port, u8 val) { writeb(val, priv->reg_base + port); } static irqreturn_t ems_pcmcia_interrupt(int irq, void *dev_id) { struct ems_pcmcia_card *card = dev_id; struct net_device *dev; irqreturn_t retval = IRQ_NONE; int i, again; /* Card not present */ if (readw(card->base_addr) != 0xAA55) return IRQ_HANDLED; do { again = 0; /* Check interrupt for each channel */ for (i = 0; i < card->channels; i++) { dev = card->net_dev[i]; if (!dev) continue; if (sja1000_interrupt(irq, dev) == IRQ_HANDLED) again = 1; } /* At least one channel handled the interrupt */ if (again) retval = IRQ_HANDLED; } while (again); return retval; } /* * Check if a CAN controller is present at the specified location * by trying to set 'em into the PeliCAN mode */ static inline int ems_pcmcia_check_chan(struct sja1000_priv *priv) { /* Make sure SJA1000 is in reset mode */ ems_pcmcia_write_reg(priv, REG_MOD, 1); ems_pcmcia_write_reg(priv, REG_CDR, CDR_PELICAN); /* read reset-values */ if (ems_pcmcia_read_reg(priv, REG_CDR) == CDR_PELICAN) return 1; return 0; } static void ems_pcmcia_del_card(struct pcmcia_device *pdev) { struct ems_pcmcia_card *card = pdev->priv; struct net_device *dev; int i; free_irq(pdev->irq, card); for (i = 0; i < card->channels; i++) { dev = card->net_dev[i]; if (!dev) continue; printk(KERN_INFO "%s: removing %s on channel #%d\n", DRV_NAME, dev->name, i); unregister_sja1000dev(dev); free_sja1000dev(dev); } writeb(EMS_CMD_UMAP, card->base_addr); iounmap(card->base_addr); kfree(card); pdev->priv = NULL; } /* * Probe PCI device for EMS CAN signature and register each available * CAN channel to SJA1000 Socket-CAN subsystem. */ static int __devinit ems_pcmcia_add_card(struct pcmcia_device *pdev, unsigned long base) { struct sja1000_priv *priv; struct net_device *dev; struct ems_pcmcia_card *card; int err, i; /* Allocating card structures to hold addresses, ... */ card = kzalloc(sizeof(struct ems_pcmcia_card), GFP_KERNEL); if (!card) return -ENOMEM; pdev->priv = card; card->channels = 0; card->base_addr = ioremap(base, EMS_PCMCIA_MEM_SIZE); if (!card->base_addr) { err = -ENOMEM; goto failure_cleanup; } /* Check for unique EMS CAN signature */ if (readw(card->base_addr) != 0xAA55) { err = -ENODEV; goto failure_cleanup; } /* Request board reset */ writeb(EMS_CMD_RESET, card->base_addr); /* Make sure CAN controllers are mapped into card's memory space */ writeb(EMS_CMD_MAP, card->base_addr); /* Detect available channels */ for (i = 0; i < EMS_PCMCIA_MAX_CHAN; i++) { dev = alloc_sja1000dev(0); if (!dev) { err = -ENOMEM; goto failure_cleanup; } card->net_dev[i] = dev; priv = netdev_priv(dev); priv->priv = card; SET_NETDEV_DEV(dev, &pdev->dev); priv->irq_flags = IRQF_SHARED; dev->irq = pdev->irq; priv->reg_base = card->base_addr + EMS_PCMCIA_CAN_BASE_OFFSET + (i * EMS_PCMCIA_CAN_CTRL_SIZE); /* Check if channel is present */ if (ems_pcmcia_check_chan(priv)) { priv->read_reg = ems_pcmcia_read_reg; priv->write_reg = ems_pcmcia_write_reg; priv->can.clock.freq = EMS_PCMCIA_CAN_CLOCK; priv->ocr = EMS_PCMCIA_OCR; priv->cdr = EMS_PCMCIA_CDR; priv->flags |= SJA1000_CUSTOM_IRQ_HANDLER; /* Register SJA1000 device */ err = register_sja1000dev(dev); if (err) { free_sja1000dev(dev); goto failure_cleanup; } card->channels++; printk(KERN_INFO "%s: registered %s on channel " "#%d at 0x%p, irq %d\n", DRV_NAME, dev->name, i, priv->reg_base, dev->irq); } else free_sja1000dev(dev); } err = request_irq(dev->irq, &ems_pcmcia_interrupt, IRQF_SHARED, DRV_NAME, card); if (!err) return 0; failure_cleanup: ems_pcmcia_del_card(pdev); return err; } /* * Setup PCMCIA socket and probe for EMS CPC-CARD */ static int __devinit ems_pcmcia_probe(struct pcmcia_device *dev) { int csval; /* General socket configuration */ dev->config_flags |= CONF_ENABLE_IRQ; dev->config_index = 1; dev->config_regs = PRESENT_OPTION; /* The io structure describes IO port mapping */ dev->resource[0]->end = 16; dev->resource[0]->flags |= IO_DATA_PATH_WIDTH_8; dev->resource[1]->end = 16; dev->resource[1]->flags |= IO_DATA_PATH_WIDTH_16; dev->io_lines = 5; /* Allocate a memory window */ dev->resource[2]->flags = (WIN_DATA_WIDTH_8 | WIN_MEMORY_TYPE_CM | WIN_ENABLE); dev->resource[2]->start = dev->resource[2]->end = 0; csval = pcmcia_request_window(dev, dev->resource[2], 0); if (csval) { dev_err(&dev->dev, "pcmcia_request_window failed (err=%d)\n", csval); return 0; } csval = pcmcia_map_mem_page(dev, dev->resource[2], dev->config_base); if (csval) { dev_err(&dev->dev, "pcmcia_map_mem_page failed (err=%d)\n", csval); return 0; } csval = pcmcia_enable_device(dev); if (csval) { dev_err(&dev->dev, "pcmcia_enable_device failed (err=%d)\n", csval); return 0; } ems_pcmcia_add_card(dev, dev->resource[2]->start); return 0; } /* * Release claimed resources */ static void ems_pcmcia_remove(struct pcmcia_device *dev) { ems_pcmcia_del_card(dev); pcmcia_disable_device(dev); } static struct pcmcia_driver ems_pcmcia_driver = { .name = DRV_NAME, .probe = ems_pcmcia_probe, .remove = ems_pcmcia_remove, .id_table = ems_pcmcia_tbl, }; static int __init ems_pcmcia_init(void) { return pcmcia_register_driver(&ems_pcmcia_driver); } module_init(ems_pcmcia_init); static void __exit ems_pcmcia_exit(void) { pcmcia_unregister_driver(&ems_pcmcia_driver); } module_exit(ems_pcmcia_exit);