diff options
Diffstat (limited to 'drivers/net/can/sja1000/ems_pci.c')
| -rw-r--r-- | drivers/net/can/sja1000/ems_pci.c | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/drivers/net/can/sja1000/ems_pci.c b/drivers/net/can/sja1000/ems_pci.c new file mode 100644 index 00000000000..121b64101d7 --- /dev/null +++ b/drivers/net/can/sja1000/ems_pci.c @@ -0,0 +1,320 @@ +/* + * Copyright (C) 2007 Wolfgang Grandegger <wg@grandegger.com> + * Copyright (C) 2008 Markus Plessing <plessing@ems-wuensche.com> + * Copyright (C) 2008 Sebastian Haas <haas@ems-wuensche.com> + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software Foundation, + * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/netdevice.h> +#include <linux/delay.h> +#include <linux/pci.h> +#include <linux/can.h> +#include <linux/can/dev.h> +#include <linux/io.h> + +#include "sja1000.h" + +#define DRV_NAME "ems_pci" + +MODULE_AUTHOR("Sebastian Haas <haas@ems-wuenche.com>"); +MODULE_DESCRIPTION("Socket-CAN driver for EMS CPC-PCI/PCIe CAN cards"); +MODULE_SUPPORTED_DEVICE("EMS CPC-PCI/PCIe CAN card"); +MODULE_LICENSE("GPL v2"); + +#define EMS_PCI_MAX_CHAN 2 + +struct ems_pci_card { + int channels; + + struct pci_dev *pci_dev; + struct net_device *net_dev[EMS_PCI_MAX_CHAN]; + + void __iomem *conf_addr; + void __iomem *base_addr; +}; + +#define EMS_PCI_CAN_CLOCK (16000000 / 2) + +/* + * Register definitions and descriptions are from LinCAN 0.3.3. + * + * PSB4610 PITA-2 bridge control registers + */ +#define PITA2_ICR 0x00 /* Interrupt Control Register */ +#define PITA2_ICR_INT0 0x00000002 /* [RC] INT0 Active/Clear */ +#define PITA2_ICR_INT0_EN 0x00020000 /* [RW] Enable INT0 */ + +#define PITA2_MISC 0x1c /* Miscellaneous Register */ +#define PITA2_MISC_CONFIG 0x04000000 /* Multiplexed parallel interface */ + +/* + * 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_PCI_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_PCI_CDR (CDR_CBP | CDR_CLKOUT_MASK) +#define EMS_PCI_MEM_SIZE 4096 /* Size of the remapped io-memory */ +#define EMS_PCI_CAN_BASE_OFFSET 0x400 /* offset where the controllers starts */ +#define EMS_PCI_CAN_CTRL_SIZE 0x200 /* memory size for each controller */ + +#define EMS_PCI_PORT_BYTES 0x4 /* Each register occupies 4 bytes */ + +#define EMS_PCI_VENDOR_ID 0x110a /* PCI device and vendor ID */ +#define EMS_PCI_DEVICE_ID 0x2104 + +static struct pci_device_id ems_pci_tbl[] = { + {EMS_PCI_VENDOR_ID, EMS_PCI_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,}, + {0,} +}; +MODULE_DEVICE_TABLE(pci, ems_pci_tbl); + +/* + * Helper to read internal registers from card logic (not CAN) + */ +static u8 ems_pci_readb(struct ems_pci_card *card, unsigned int port) +{ + return readb(card->base_addr + (port * EMS_PCI_PORT_BYTES)); +} + +static u8 ems_pci_read_reg(const struct sja1000_priv *priv, int port) +{ + return readb(priv->reg_base + (port * EMS_PCI_PORT_BYTES)); +} + +static void ems_pci_write_reg(const struct sja1000_priv *priv, int port, u8 val) +{ + writeb(val, priv->reg_base + (port * EMS_PCI_PORT_BYTES)); +} + +static void ems_pci_post_irq(const struct sja1000_priv *priv) +{ + struct ems_pci_card *card = (struct ems_pci_card *)priv->priv; + + /* reset int flag of pita */ + writel(PITA2_ICR_INT0_EN | PITA2_ICR_INT0, card->conf_addr + + PITA2_ICR); +} + +/* + * Check if a CAN controller is present at the specified location + * by trying to set 'em into the PeliCAN mode + */ +static inline int ems_pci_check_chan(const struct sja1000_priv *priv) +{ + unsigned char res; + + /* Make sure SJA1000 is in reset mode */ + ems_pci_write_reg(priv, REG_MOD, 1); + + ems_pci_write_reg(priv, REG_CDR, CDR_PELICAN); + + /* read reset-values */ + res = ems_pci_read_reg(priv, REG_CDR); + + if (res == CDR_PELICAN) + return 1; + + return 0; +} + +static void ems_pci_del_card(struct pci_dev *pdev) +{ + struct ems_pci_card *card = pci_get_drvdata(pdev); + struct net_device *dev; + int i = 0; + + for (i = 0; i < card->channels; i++) { + dev = card->net_dev[i]; + + if (!dev) + continue; + + dev_info(&pdev->dev, "Removing %s.\n", dev->name); + unregister_sja1000dev(dev); + free_sja1000dev(dev); + } + + if (card->base_addr != NULL) + pci_iounmap(card->pci_dev, card->base_addr); + + if (card->conf_addr != NULL) + pci_iounmap(card->pci_dev, card->conf_addr); + + kfree(card); + + pci_disable_device(pdev); + pci_set_drvdata(pdev, NULL); +} + +static void ems_pci_card_reset(struct ems_pci_card *card) +{ + /* Request board reset */ + writeb(0, card->base_addr); +} + +/* + * Probe PCI device for EMS CAN signature and register each available + * CAN channel to SJA1000 Socket-CAN subsystem. + */ +static int __devinit ems_pci_add_card(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + struct sja1000_priv *priv; + struct net_device *dev; + struct ems_pci_card *card; + int err, i; + + /* Enabling PCI device */ + if (pci_enable_device(pdev) < 0) { + dev_err(&pdev->dev, "Enabling PCI device failed\n"); + return -ENODEV; + } + + /* Allocating card structures to hold addresses, ... */ + card = kzalloc(sizeof(struct ems_pci_card), GFP_KERNEL); + if (card == NULL) { + dev_err(&pdev->dev, "Unable to allocate memory\n"); + pci_disable_device(pdev); + return -ENOMEM; + } + + pci_set_drvdata(pdev, card); + + card->pci_dev = pdev; + + card->channels = 0; + + /* Remap PITA configuration space, and controller memory area */ + card->conf_addr = pci_iomap(pdev, 0, EMS_PCI_MEM_SIZE); + if (card->conf_addr == NULL) { + err = -ENOMEM; + goto failure_cleanup; + } + + card->base_addr = pci_iomap(pdev, 1, EMS_PCI_MEM_SIZE); + if (card->base_addr == NULL) { + err = -ENOMEM; + goto failure_cleanup; + } + + /* Configure PITA-2 parallel interface (enable MUX) */ + writel(PITA2_MISC_CONFIG, card->conf_addr + PITA2_MISC); + + /* Check for unique EMS CAN signature */ + if (ems_pci_readb(card, 0) != 0x55 || + ems_pci_readb(card, 1) != 0xAA || + ems_pci_readb(card, 2) != 0x01 || + ems_pci_readb(card, 3) != 0xCB || + ems_pci_readb(card, 4) != 0x11) { + dev_err(&pdev->dev, "Not EMS Dr. Thomas Wuensche interface\n"); + err = -ENODEV; + goto failure_cleanup; + } + + ems_pci_card_reset(card); + + /* Detect available channels */ + for (i = 0; i < EMS_PCI_MAX_CHAN; i++) { + dev = alloc_sja1000dev(0); + if (dev == NULL) { + err = -ENOMEM; + goto failure_cleanup; + } + + card->net_dev[i] = dev; + priv = netdev_priv(dev); + priv->priv = card; + priv->irq_flags = IRQF_SHARED; + + dev->irq = pdev->irq; + priv->reg_base = card->base_addr + EMS_PCI_CAN_BASE_OFFSET + + (i * EMS_PCI_CAN_CTRL_SIZE); + + /* Check if channel is present */ + if (ems_pci_check_chan(priv)) { + priv->read_reg = ems_pci_read_reg; + priv->write_reg = ems_pci_write_reg; + priv->post_irq = ems_pci_post_irq; + priv->can.clock.freq = EMS_PCI_CAN_CLOCK; + priv->ocr = EMS_PCI_OCR; + priv->cdr = EMS_PCI_CDR; + + SET_NETDEV_DEV(dev, &pdev->dev); + + /* Enable interrupts from card */ + writel(PITA2_ICR_INT0_EN, card->conf_addr + PITA2_ICR); + + /* Register SJA1000 device */ + err = register_sja1000dev(dev); + if (err) { + dev_err(&pdev->dev, "Registering device failed " + "(err=%d)\n", err); + free_sja1000dev(dev); + goto failure_cleanup; + } + + card->channels++; + + dev_info(&pdev->dev, "Channel #%d at 0x%p, irq %d\n", + i + 1, priv->reg_base, dev->irq); + } else { + free_sja1000dev(dev); + } + } + + return 0; + +failure_cleanup: + dev_err(&pdev->dev, "Error: %d. Cleaning Up.\n", err); + + ems_pci_del_card(pdev); + + return err; +} + +static struct pci_driver ems_pci_driver = { + .name = DRV_NAME, + .id_table = ems_pci_tbl, + .probe = ems_pci_add_card, + .remove = ems_pci_del_card, +}; + +static int __init ems_pci_init(void) +{ + return pci_register_driver(&ems_pci_driver); +} + +static void __exit ems_pci_exit(void) +{ + pci_unregister_driver(&ems_pci_driver); +} + +module_init(ems_pci_init); +module_exit(ems_pci_exit); + |