diff options
Diffstat (limited to 'drivers/net/can/sja1000/ems_pcmcia.c')
| -rw-r--r-- | drivers/net/can/sja1000/ems_pcmcia.c | 316 |
1 files changed, 316 insertions, 0 deletions
diff --git a/drivers/net/can/sja1000/ems_pcmcia.c b/drivers/net/can/sja1000/ems_pcmcia.c new file mode 100644 index 000000000..4642b6d4a --- /dev/null +++ b/drivers/net/can/sja1000/ems_pcmcia.c @@ -0,0 +1,316 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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> + */ + +#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_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, SJA1000_MOD, 1); + ems_pcmcia_write_reg(priv, SJA1000_CDR, CDR_PELICAN); + + /* read reset-values */ + if (ems_pcmcia_read_reg(priv, SJA1000_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 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); + dev->dev_id = i; + + 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); + } + + if (!card->channels) { + err = -ENODEV; + goto failure_cleanup; + } + + err = request_irq(pdev->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 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, +}; +module_pcmcia_driver(ems_pcmcia_driver); |