drivers/net/can/sja1000/peak_pcmcia.c - kernel/msm-4.19 - Gitiles

 /*
  * Copyright (C) 2010-2012 Stephane Grosjean <s.grosjean@peak-system.com>
  *
  * CAN driver for PEAK-System PCAN-PC Card
  * Derived from the PCAN project file driver/src/pcan_pccard.c
  * Copyright (C) 2006-2010 PEAK System-Technik GmbH
  *
  * 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/timer.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"

 MODULE_AUTHOR("Stephane Grosjean <s.grosjean@peak-system.com>");
 MODULE_DESCRIPTION("CAN driver for PEAK-System PCAN-PC Cards");
 MODULE_LICENSE("GPL v2");
 MODULE_SUPPORTED_DEVICE("PEAK PCAN-PC Card");

 /* PEAK-System PCMCIA driver name */
 #define PCC_NAME		"peak_pcmcia"

 #define PCC_CHAN_MAX		2

 #define PCC_CAN_CLOCK		(16000000 / 2)

 #define PCC_MANF_ID		0x0377
 #define PCC_CARD_ID		0x0001

 #define PCC_CHAN_SIZE		0x20
 #define PCC_CHAN_OFF(c)		((c) * PCC_CHAN_SIZE)
 #define PCC_COMN_OFF		(PCC_CHAN_OFF(PCC_CHAN_MAX))
 #define PCC_COMN_SIZE		0x40

 /* common area registers */
 #define PCC_CCR			0x00
 #define PCC_CSR			0x02
 #define PCC_CPR			0x04
 #define PCC_SPI_DIR		0x06
 #define PCC_SPI_DOR		0x08
 #define PCC_SPI_ADR		0x0a
 #define PCC_SPI_IR		0x0c
 #define PCC_FW_MAJOR		0x10
 #define PCC_FW_MINOR		0x12

 /* CCR bits */
 #define PCC_CCR_CLK_16		0x00
 #define PCC_CCR_CLK_10		0x01
 #define PCC_CCR_CLK_21		0x02
 #define PCC_CCR_CLK_8		0x03
 #define PCC_CCR_CLK_MASK	PCC_CCR_CLK_8

 #define PCC_CCR_RST_CHAN(c)	(0x01 << ((c) + 2))
 #define PCC_CCR_RST_ALL		(PCC_CCR_RST_CHAN(0) | PCC_CCR_RST_CHAN(1))
 #define PCC_CCR_RST_MASK	PCC_CCR_RST_ALL

 /* led selection bits */
 #define PCC_LED(c)		(1 << (c))
 #define PCC_LED_ALL		(PCC_LED(0) | PCC_LED(1))

 /* led state value */
 #define PCC_LED_ON		0x00
 #define PCC_LED_FAST		0x01
 #define PCC_LED_SLOW		0x02
 #define PCC_LED_OFF		0x03

 #define PCC_CCR_LED_CHAN(s, c)	((s) << (((c) + 2) << 1))

 #define PCC_CCR_LED_ON_CHAN(c)		PCC_CCR_LED_CHAN(PCC_LED_ON, c)
 #define PCC_CCR_LED_FAST_CHAN(c)	PCC_CCR_LED_CHAN(PCC_LED_FAST, c)
 #define PCC_CCR_LED_SLOW_CHAN(c)	PCC_CCR_LED_CHAN(PCC_LED_SLOW, c)
 #define PCC_CCR_LED_OFF_CHAN(c)		PCC_CCR_LED_CHAN(PCC_LED_OFF, c)
 #define PCC_CCR_LED_MASK_CHAN(c)	PCC_CCR_LED_OFF_CHAN(c)
 #define PCC_CCR_LED_OFF_ALL		(PCC_CCR_LED_OFF_CHAN(0) | \
 					 PCC_CCR_LED_OFF_CHAN(1))
 #define PCC_CCR_LED_MASK		PCC_CCR_LED_OFF_ALL

 #define PCC_CCR_INIT	(PCC_CCR_CLK_16 | PCC_CCR_RST_ALL | PCC_CCR_LED_OFF_ALL)

 /* CSR bits */
 #define PCC_CSR_SPI_BUSY		0x04

 /* time waiting for SPI busy (prevent from infinite loop) */
 #define PCC_SPI_MAX_BUSY_WAIT_MS	3

 /* max count of reading the SPI status register waiting for a change */
 /* (prevent from infinite loop) */
 #define PCC_WRITE_MAX_LOOP		1000

 /* max nb of int handled by that isr in one shot (prevent from infinite loop) */
 #define PCC_ISR_MAX_LOOP		10

 /* EEPROM chip instruction set */
 /* note: EEPROM Read/Write instructions include A8 bit */
 #define PCC_EEP_WRITE(a)	(0x02 | (((a) & 0x100) >> 5))
 #define PCC_EEP_READ(a)		(0x03 | (((a) & 0x100) >> 5))
 #define PCC_EEP_WRDI		0x04	/* EEPROM Write Disable */
 #define PCC_EEP_RDSR		0x05	/* EEPROM Read Status Register */
 #define PCC_EEP_WREN		0x06	/* EEPROM Write Enable */

 /* EEPROM Status Register bits */
 #define PCC_EEP_SR_WEN		0x02	/* EEPROM SR Write Enable bit */
 #define PCC_EEP_SR_WIP		0x01	/* EEPROM SR Write In Progress bit */

 /*
  * 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 PCC_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 PCC_CDR			(CDR_CBP | CDR_CLKOUT_MASK)

 struct pcan_channel {
 	struct net_device *netdev;
 	unsigned long prev_rx_bytes;
 	unsigned long prev_tx_bytes;
 };

 /* PCAN-PC Card private structure */
 struct pcan_pccard {
 	struct pcmcia_device *pdev;
 	int chan_count;
 	struct pcan_channel channel[PCC_CHAN_MAX];
 	u8 ccr;
 	u8 fw_major;
 	u8 fw_minor;
 	void __iomem *ioport_addr;
 	struct timer_list led_timer;
 };

 static struct pcmcia_device_id pcan_table[] = {
 	PCMCIA_DEVICE_MANF_CARD(PCC_MANF_ID, PCC_CARD_ID),
 	PCMCIA_DEVICE_NULL,
 };

 MODULE_DEVICE_TABLE(pcmcia, pcan_table);

 static void pcan_set_leds(struct pcan_pccard *card, u8 mask, u8 state);

 /*
  * start timer which controls leds state
  */
 static void pcan_start_led_timer(struct pcan_pccard *card)
 {
 	if (!timer_pending(&card->led_timer))
 		mod_timer(&card->led_timer, jiffies + HZ);
 }

 /*
  * stop the timer which controls leds state
  */
 static void pcan_stop_led_timer(struct pcan_pccard *card)
 {
 	del_timer_sync(&card->led_timer);
 }

 /*
  * read a sja1000 register
  */
 static u8 pcan_read_canreg(const struct sja1000_priv *priv, int port)
 {
 	return ioread8(priv->reg_base + port);
 }

 /*
  * write a sja1000 register
  */
 static void pcan_write_canreg(const struct sja1000_priv *priv, int port, u8 v)
 {
 	struct pcan_pccard *card = priv->priv;
 	int c = (priv->reg_base - card->ioport_addr) / PCC_CHAN_SIZE;

 	/* sja1000 register changes control the leds state */
 	if (port == REG_MOD)
 		switch (v) {
 		case MOD_RM:
 			/* Reset Mode: set led on */
 			pcan_set_leds(card, PCC_LED(c), PCC_LED_ON);
 			break;
 		case 0x00:
 			/* Normal Mode: led slow blinking and start led timer */
 			pcan_set_leds(card, PCC_LED(c), PCC_LED_SLOW);
 			pcan_start_led_timer(card);
 			break;
 		default:
 			break;
 		}

 	iowrite8(v, priv->reg_base + port);
 }

 /*
  * read a register from the common area
  */
 static u8 pcan_read_reg(struct pcan_pccard *card, int port)
 {
 	return ioread8(card->ioport_addr + PCC_COMN_OFF + port);
 }

 /*
  * write a register into the common area
  */
 static void pcan_write_reg(struct pcan_pccard *card, int port, u8 v)
 {
 	/* cache ccr value */
 	if (port == PCC_CCR) {
 		if (card->ccr == v)
 			return;
 		card->ccr = v;
 	}

 	iowrite8(v, card->ioport_addr + PCC_COMN_OFF + port);
 }

 /*
  * check whether the card is present by checking its fw version numbers
  * against values read at probing time.
  */
 static inline int pcan_pccard_present(struct pcan_pccard *card)
 {
 	return ((pcan_read_reg(card, PCC_FW_MAJOR) == card->fw_major) &&
 		(pcan_read_reg(card, PCC_FW_MINOR) == card->fw_minor));
 }

 /*
  * wait for SPI engine while it is busy
  */
 static int pcan_wait_spi_busy(struct pcan_pccard *card)
 {
 	unsigned long timeout = jiffies +
 				msecs_to_jiffies(PCC_SPI_MAX_BUSY_WAIT_MS) + 1;

 	/* be sure to read status at least once after sleeping */
 	while (pcan_read_reg(card, PCC_CSR) & PCC_CSR_SPI_BUSY) {
 		if (time_after(jiffies, timeout))
 			return -EBUSY;
 		schedule();
 	}

 	return 0;
 }

 /*
  * write data in device eeprom
  */
 static int pcan_write_eeprom(struct pcan_pccard *card, u16 addr, u8 v)
 {
 	u8 status;
 	int err, i;

 	/* write instruction enabling write */
 	pcan_write_reg(card, PCC_SPI_IR, PCC_EEP_WREN);
 	err = pcan_wait_spi_busy(card);
 	if (err)
 		goto we_spi_err;

 	/* wait until write enabled */
 	for (i = 0; i < PCC_WRITE_MAX_LOOP; i++) {
 		/* write instruction reading the status register */
 		pcan_write_reg(card, PCC_SPI_IR, PCC_EEP_RDSR);
 		err = pcan_wait_spi_busy(card);
 		if (err)
 			goto we_spi_err;

 		/* get status register value and check write enable bit */
 		status = pcan_read_reg(card, PCC_SPI_DIR);
 		if (status & PCC_EEP_SR_WEN)
 			break;
 	}

 	if (i >= PCC_WRITE_MAX_LOOP) {
 		dev_err(&card->pdev->dev,
 			"stop waiting to be allowed to write in eeprom\n");
 		return -EIO;
 	}

 	/* set address and data */
 	pcan_write_reg(card, PCC_SPI_ADR, addr & 0xff);
 	pcan_write_reg(card, PCC_SPI_DOR, v);

 	/*
 	 * write instruction with bit[3] set according to address value:
 	 * if addr refers to upper half of the memory array: bit[3] = 1
 	 */
 	pcan_write_reg(card, PCC_SPI_IR, PCC_EEP_WRITE(addr));
 	err = pcan_wait_spi_busy(card);
 	if (err)
 		goto we_spi_err;

 	/* wait while write in progress */
 	for (i = 0; i < PCC_WRITE_MAX_LOOP; i++) {
 		/* write instruction reading the status register */
 		pcan_write_reg(card, PCC_SPI_IR, PCC_EEP_RDSR);
 		err = pcan_wait_spi_busy(card);
 		if (err)
 			goto we_spi_err;

 		/* get status register value and check write in progress bit */
 		status = pcan_read_reg(card, PCC_SPI_DIR);
 		if (!(status & PCC_EEP_SR_WIP))
 			break;
 	}

 	if (i >= PCC_WRITE_MAX_LOOP) {
 		dev_err(&card->pdev->dev,
 			"stop waiting for write in eeprom to complete\n");
 		return -EIO;
 	}

 	/* write instruction disabling write */
 	pcan_write_reg(card, PCC_SPI_IR, PCC_EEP_WRDI);
 	err = pcan_wait_spi_busy(card);
 	if (err)
 		goto we_spi_err;

 	return 0;

 we_spi_err:
 	dev_err(&card->pdev->dev,
 		"stop waiting (spi engine always busy) err %d\n", err);

 	return err;
 }

 static void pcan_set_leds(struct pcan_pccard *card, u8 led_mask, u8 state)
 {
 	u8 ccr = card->ccr;
 	int i;

 	for (i = 0; i < card->chan_count; i++)
 		if (led_mask & PCC_LED(i)) {
 			/* clear corresponding led bits in ccr */
 			ccr &= ~PCC_CCR_LED_MASK_CHAN(i);
 			/* then set new bits */
 			ccr |= PCC_CCR_LED_CHAN(state, i);
 		}

 	/* real write only if something has changed in ccr */
 	pcan_write_reg(card, PCC_CCR, ccr);
 }

 /*
  * enable/disable CAN connectors power
  */
 static inline void pcan_set_can_power(struct pcan_pccard *card, int onoff)
 {
 	int err;

 	err = pcan_write_eeprom(card, 0, !!onoff);
 	if (err)
 		dev_err(&card->pdev->dev,
 			"failed setting power %s to can connectors (err %d)\n",
 			(onoff) ? "on" : "off", err);
 }

 /*
  * set leds state according to channel activity
  */
 static void pcan_led_timer(unsigned long arg)
 {
 	struct pcan_pccard *card = (struct pcan_pccard *)arg;
 	struct net_device *netdev;
 	int i, up_count = 0;
 	u8 ccr;

 	ccr = card->ccr;
 	for (i = 0; i < card->chan_count; i++) {
 		/* default is: not configured */
 		ccr &= ~PCC_CCR_LED_MASK_CHAN(i);
 		ccr |= PCC_CCR_LED_ON_CHAN(i);

 		netdev = card->channel[i].netdev;
 		if (!netdev || !(netdev->flags & IFF_UP))
 			continue;

 		up_count++;

 		/* no activity (but configured) */
 		ccr &= ~PCC_CCR_LED_MASK_CHAN(i);
 		ccr |= PCC_CCR_LED_SLOW_CHAN(i);

 		/* if bytes counters changed, set fast blinking led */
 		if (netdev->stats.rx_bytes != card->channel[i].prev_rx_bytes) {
 			card->channel[i].prev_rx_bytes = netdev->stats.rx_bytes;
 			ccr &= ~PCC_CCR_LED_MASK_CHAN(i);
 			ccr |= PCC_CCR_LED_FAST_CHAN(i);
 		}
 		if (netdev->stats.tx_bytes != card->channel[i].prev_tx_bytes) {
 			card->channel[i].prev_tx_bytes = netdev->stats.tx_bytes;
 			ccr &= ~PCC_CCR_LED_MASK_CHAN(i);
 			ccr |= PCC_CCR_LED_FAST_CHAN(i);
 		}
 	}

 	/* write the new leds state */
 	pcan_write_reg(card, PCC_CCR, ccr);

 	/* restart timer (except if no more configured channels) */
 	if (up_count)
 		mod_timer(&card->led_timer, jiffies + HZ);
 }

 /*
  * interrupt service routine
  */
 static irqreturn_t pcan_isr(int irq, void *dev_id)
 {
 	struct pcan_pccard *card = dev_id;
 	int irq_handled;

 	/* prevent from infinite loop */
 	for (irq_handled = 0; irq_handled < PCC_ISR_MAX_LOOP; irq_handled++) {
 		/* handle shared interrupt and next loop */
 		int nothing_to_handle = 1;
 		int i;

 		/* check interrupt for each channel */
 		for (i = 0; i < card->chan_count; i++) {
 			struct net_device *netdev;

 			/*
 			 * check whether the card is present before calling
 			 * sja1000_interrupt() to speed up hotplug detection
 			 */
 			if (!pcan_pccard_present(card)) {
 				/* card unplugged during isr */
 				return IRQ_NONE;
 			}

 			/*
 			 * should check whether all or SJA1000_MAX_IRQ
 			 * interrupts have been handled: loop again to be sure.
 			 */
 			netdev = card->channel[i].netdev;
 			if (netdev &&
 			    sja1000_interrupt(irq, netdev) == IRQ_HANDLED)
 				nothing_to_handle = 0;
 		}

 		if (nothing_to_handle)
 			break;
 	}

 	return (irq_handled) ? IRQ_HANDLED : IRQ_NONE;
 }

 /*
  * free all resources used by the channels and switch off leds and can power
  */
 static void pcan_free_channels(struct pcan_pccard *card)
 {
 	int i;
 	u8 led_mask = 0;

 	for (i = 0; i < card->chan_count; i++) {
 		struct net_device *netdev;
 		char name[IFNAMSIZ];

 		led_mask |= PCC_LED(i);

 		netdev = card->channel[i].netdev;
 		if (!netdev)
 			continue;

 		strncpy(name, netdev->name, IFNAMSIZ);

 		unregister_sja1000dev(netdev);

 		free_sja1000dev(netdev);

 		dev_info(&card->pdev->dev, "%s removed\n", name);
 	}

 	/* do it only if device not removed */
 	if (pcan_pccard_present(card)) {
 		pcan_set_leds(card, led_mask, PCC_LED_OFF);
 		pcan_set_can_power(card, 0);
 	}
 }

 /*
  * check if a CAN controller is present at the specified location
  */
 static inline int pcan_channel_present(struct sja1000_priv *priv)
 {
 	/* make sure SJA1000 is in reset mode */
 	pcan_write_canreg(priv, REG_MOD, 1);
 	pcan_write_canreg(priv, REG_CDR, CDR_PELICAN);

 	/* read reset-values */
 	if (pcan_read_canreg(priv, REG_CDR) == CDR_PELICAN)
 		return 1;

 	return 0;
 }

 static int pcan_add_channels(struct pcan_pccard *card)
 {
 	struct pcmcia_device *pdev = card->pdev;
 	int i, err = 0;
 	u8 ccr = PCC_CCR_INIT;

 	/* init common registers (reset channels and leds off) */
 	card->ccr = ~ccr;
 	pcan_write_reg(card, PCC_CCR, ccr);

 	/* wait 2ms before unresetting channels */
 	mdelay(2);

 	ccr &= ~PCC_CCR_RST_ALL;
 	pcan_write_reg(card, PCC_CCR, ccr);

 	/* create one network device per channel detected */
 	for (i = 0; i < ARRAY_SIZE(card->channel); i++) {
 		struct net_device *netdev;
 		struct sja1000_priv *priv;

 		netdev = alloc_sja1000dev(0);
 		if (!netdev) {
 			err = -ENOMEM;
 			break;
 		}

 		/* update linkages */
 		priv = netdev_priv(netdev);
 		priv->priv = card;
 		SET_NETDEV_DEV(netdev, &pdev->dev);

 		priv->irq_flags = IRQF_SHARED;
 		netdev->irq = pdev->irq;
 		priv->reg_base = card->ioport_addr + PCC_CHAN_OFF(i);

 		/* check if channel is present */
 		if (!pcan_channel_present(priv)) {
 			dev_err(&pdev->dev, "channel %d not present\n", i);
 			free_sja1000dev(netdev);
 			continue;
 		}

 		priv->read_reg  = pcan_read_canreg;
 		priv->write_reg = pcan_write_canreg;
 		priv->can.clock.freq = PCC_CAN_CLOCK;
 		priv->ocr = PCC_OCR;
 		priv->cdr = PCC_CDR;

 		/* Neither a slave device distributes the clock */
 		if (i > 0)
 			priv->cdr |= CDR_CLK_OFF;

 		priv->flags |= SJA1000_CUSTOM_IRQ_HANDLER;

 		/* register SJA1000 device */
 		err = register_sja1000dev(netdev);
 		if (err) {
 			free_sja1000dev(netdev);
 			continue;
 		}

 		card->channel[i].netdev = netdev;
 		card->chan_count++;

 		/* set corresponding led on in the new ccr */
 		ccr &= ~PCC_CCR_LED_OFF_CHAN(i);

 		dev_info(&pdev->dev,
 			"%s on channel %d at 0x%p irq %d\n",
 			netdev->name, i, priv->reg_base, pdev->irq);
 	}

 	/* write new ccr (change leds state) */
 	pcan_write_reg(card, PCC_CCR, ccr);

 	return err;
 }

 static int pcan_conf_check(struct pcmcia_device *pdev, void *priv_data)
 {
 	pdev->resource[0]->flags &= ~IO_DATA_PATH_WIDTH;
 	pdev->resource[0]->flags |= IO_DATA_PATH_WIDTH_8; /* only */
 	pdev->io_lines = 10;

 	/* This reserves IO space but doesn't actually enable it */
 	return pcmcia_request_io(pdev);
 }

 /*
  * free all resources used by the device
  */
 static void pcan_free(struct pcmcia_device *pdev)
 {
 	struct pcan_pccard *card = pdev->priv;

 	if (!card)
 		return;

 	free_irq(pdev->irq, card);
 	pcan_stop_led_timer(card);

 	pcan_free_channels(card);

 	ioport_unmap(card->ioport_addr);

 	kfree(card);
 	pdev->priv = NULL;
 }

 /*
  * setup PCMCIA socket and probe for PEAK-System PC-CARD
  */
 static int pcan_probe(struct pcmcia_device *pdev)
 {
 	struct pcan_pccard *card;
 	int err;

 	pdev->config_flags |= CONF_ENABLE_IRQ | CONF_AUTO_SET_IO;

 	err = pcmcia_loop_config(pdev, pcan_conf_check, NULL);
 	if (err) {
 		dev_err(&pdev->dev, "pcmcia_loop_config() error %d\n", err);
 		goto probe_err_1;
 	}

 	if (!pdev->irq) {
 		dev_err(&pdev->dev, "no irq assigned\n");
 		err = -ENODEV;
 		goto probe_err_1;
 	}

 	err = pcmcia_enable_device(pdev);
 	if (err) {
 		dev_err(&pdev->dev, "pcmcia_enable_device failed err=%d\n",
 			err);
 		goto probe_err_1;
 	}

 	card = kzalloc(sizeof(struct pcan_pccard), GFP_KERNEL);
 	if (!card) {
 		err = -ENOMEM;
 		goto probe_err_2;
 	}

 	card->pdev = pdev;
 	pdev->priv = card;

 	/* sja1000 api uses iomem */
 	card->ioport_addr = ioport_map(pdev->resource[0]->start,
 					resource_size(pdev->resource[0]));
 	if (!card->ioport_addr) {
 		dev_err(&pdev->dev, "couldn't map io port into io memory\n");
 		err = -ENOMEM;
 		goto probe_err_3;
 	}
 	card->fw_major = pcan_read_reg(card, PCC_FW_MAJOR);
 	card->fw_minor = pcan_read_reg(card, PCC_FW_MINOR);

 	/* display board name and firware version */
 	dev_info(&pdev->dev, "PEAK-System pcmcia card %s fw %d.%d\n",
 		pdev->prod_id[1] ? pdev->prod_id[1] : "PCAN-PC Card",
 		card->fw_major, card->fw_minor);

 	/* detect available channels */
 	pcan_add_channels(card);
 	if (!card->chan_count) {
 		err = -ENOMEM;
 		goto probe_err_4;
 	}

 	/* init the timer which controls the leds */
 	init_timer(&card->led_timer);
 	card->led_timer.function = pcan_led_timer;
 	card->led_timer.data = (unsigned long)card;

 	/* request the given irq */
 	err = request_irq(pdev->irq, &pcan_isr, IRQF_SHARED, PCC_NAME, card);
 	if (err) {
 		dev_err(&pdev->dev, "couldn't request irq%d\n", pdev->irq);
 		goto probe_err_5;
 	}

 	/* power on the connectors */
 	pcan_set_can_power(card, 1);

 	return 0;

 probe_err_5:
 	/* unregister can devices from network */
 	pcan_free_channels(card);

 probe_err_4:
 	ioport_unmap(card->ioport_addr);

 probe_err_3:
 	kfree(card);
 	pdev->priv = NULL;

 probe_err_2:
 	pcmcia_disable_device(pdev);

 probe_err_1:
 	return err;
 }

 /*
  * release claimed resources
  */
 static void pcan_remove(struct pcmcia_device *pdev)
 {
 	pcan_free(pdev);
 	pcmcia_disable_device(pdev);
 }

 static struct pcmcia_driver pcan_driver = {
 	.name = PCC_NAME,
 	.probe = pcan_probe,
 	.remove = pcan_remove,
 	.id_table = pcan_table,
 };

 static int __init pcan_init(void)
 {
 	return pcmcia_register_driver(&pcan_driver);
 }
 module_init(pcan_init);

 static void __exit pcan_exit(void)
 {
 	pcmcia_unregister_driver(&pcan_driver);
 }
 module_exit(pcan_exit);
	/*
	* Copyright (C) 2010-2012 Stephane Grosjean <s.grosjean@peak-system.com>
	*
	* CAN driver for PEAK-System PCAN-PC Card
	* Derived from the PCAN project file driver/src/pcan_pccard.c
	* Copyright (C) 2006-2010 PEAK System-Technik GmbH
	*
	* 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/timer.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"

	MODULE_AUTHOR("Stephane Grosjean <s.grosjean@peak-system.com>");
	MODULE_DESCRIPTION("CAN driver for PEAK-System PCAN-PC Cards");
	MODULE_LICENSE("GPL v2");
	MODULE_SUPPORTED_DEVICE("PEAK PCAN-PC Card");

	/* PEAK-System PCMCIA driver name */
	#define PCC_NAME "peak_pcmcia"

	#define PCC_CHAN_MAX 2

	#define PCC_CAN_CLOCK (16000000 / 2)

	#define PCC_MANF_ID 0x0377
	#define PCC_CARD_ID 0x0001

	#define PCC_CHAN_SIZE 0x20
	#define PCC_CHAN_OFF(c) ((c) * PCC_CHAN_SIZE)
	#define PCC_COMN_OFF (PCC_CHAN_OFF(PCC_CHAN_MAX))
	#define PCC_COMN_SIZE 0x40

	/* common area registers */
	#define PCC_CCR 0x00
	#define PCC_CSR 0x02
	#define PCC_CPR 0x04
	#define PCC_SPI_DIR 0x06
	#define PCC_SPI_DOR 0x08
	#define PCC_SPI_ADR 0x0a
	#define PCC_SPI_IR 0x0c
	#define PCC_FW_MAJOR 0x10
	#define PCC_FW_MINOR 0x12

	/* CCR bits */
	#define PCC_CCR_CLK_16 0x00
	#define PCC_CCR_CLK_10 0x01
	#define PCC_CCR_CLK_21 0x02
	#define PCC_CCR_CLK_8 0x03
	#define PCC_CCR_CLK_MASK PCC_CCR_CLK_8

	#define PCC_CCR_RST_CHAN(c) (0x01 << ((c) + 2))
	#define PCC_CCR_RST_ALL (PCC_CCR_RST_CHAN(0) \| PCC_CCR_RST_CHAN(1))
	#define PCC_CCR_RST_MASK PCC_CCR_RST_ALL

	/* led selection bits */
	#define PCC_LED(c) (1 << (c))
	#define PCC_LED_ALL (PCC_LED(0) \| PCC_LED(1))

	/* led state value */
	#define PCC_LED_ON 0x00
	#define PCC_LED_FAST 0x01
	#define PCC_LED_SLOW 0x02
	#define PCC_LED_OFF 0x03

	#define PCC_CCR_LED_CHAN(s, c) ((s) << (((c) + 2) << 1))

	#define PCC_CCR_LED_ON_CHAN(c) PCC_CCR_LED_CHAN(PCC_LED_ON, c)
	#define PCC_CCR_LED_FAST_CHAN(c) PCC_CCR_LED_CHAN(PCC_LED_FAST, c)
	#define PCC_CCR_LED_SLOW_CHAN(c) PCC_CCR_LED_CHAN(PCC_LED_SLOW, c)
	#define PCC_CCR_LED_OFF_CHAN(c) PCC_CCR_LED_CHAN(PCC_LED_OFF, c)
	#define PCC_CCR_LED_MASK_CHAN(c) PCC_CCR_LED_OFF_CHAN(c)
	#define PCC_CCR_LED_OFF_ALL (PCC_CCR_LED_OFF_CHAN(0) \| \
	PCC_CCR_LED_OFF_CHAN(1))
	#define PCC_CCR_LED_MASK PCC_CCR_LED_OFF_ALL

	#define PCC_CCR_INIT (PCC_CCR_CLK_16 \| PCC_CCR_RST_ALL \| PCC_CCR_LED_OFF_ALL)

	/* CSR bits */
	#define PCC_CSR_SPI_BUSY 0x04

	/* time waiting for SPI busy (prevent from infinite loop) */
	#define PCC_SPI_MAX_BUSY_WAIT_MS 3

	/* max count of reading the SPI status register waiting for a change */
	/* (prevent from infinite loop) */
	#define PCC_WRITE_MAX_LOOP 1000

	/* max nb of int handled by that isr in one shot (prevent from infinite loop) */
	#define PCC_ISR_MAX_LOOP 10

	/* EEPROM chip instruction set */
	/* note: EEPROM Read/Write instructions include A8 bit */
	#define PCC_EEP_WRITE(a) (0x02 \| (((a) & 0x100) >> 5))
	#define PCC_EEP_READ(a) (0x03 \| (((a) & 0x100) >> 5))
	#define PCC_EEP_WRDI 0x04 /* EEPROM Write Disable */
	#define PCC_EEP_RDSR 0x05 /* EEPROM Read Status Register */
	#define PCC_EEP_WREN 0x06 /* EEPROM Write Enable */

	/* EEPROM Status Register bits */
	#define PCC_EEP_SR_WEN 0x02 /* EEPROM SR Write Enable bit */
	#define PCC_EEP_SR_WIP 0x01 /* EEPROM SR Write In Progress bit */

	/*
	* 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 PCC_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 PCC_CDR (CDR_CBP \| CDR_CLKOUT_MASK)

	struct pcan_channel {
	struct net_device *netdev;
	unsigned long prev_rx_bytes;
	unsigned long prev_tx_bytes;
	};

	/* PCAN-PC Card private structure */
	struct pcan_pccard {
	struct pcmcia_device *pdev;
	int chan_count;
	struct pcan_channel channel[PCC_CHAN_MAX];
	u8 ccr;
	u8 fw_major;
	u8 fw_minor;
	void __iomem *ioport_addr;
	struct timer_list led_timer;
	};

	static struct pcmcia_device_id pcan_table[] = {
	PCMCIA_DEVICE_MANF_CARD(PCC_MANF_ID, PCC_CARD_ID),
	PCMCIA_DEVICE_NULL,
	};

	MODULE_DEVICE_TABLE(pcmcia, pcan_table);

	static void pcan_set_leds(struct pcan_pccard *card, u8 mask, u8 state);

	/*
	* start timer which controls leds state
	*/
	static void pcan_start_led_timer(struct pcan_pccard *card)
	{
	if (!timer_pending(&card->led_timer))
	mod_timer(&card->led_timer, jiffies + HZ);
	}

	/*
	* stop the timer which controls leds state
	*/
	static void pcan_stop_led_timer(struct pcan_pccard *card)
	{
	del_timer_sync(&card->led_timer);
	}

	/*
	* read a sja1000 register
	*/
	static u8 pcan_read_canreg(const struct sja1000_priv *priv, int port)
	{
	return ioread8(priv->reg_base + port);
	}

	/*
	* write a sja1000 register
	*/
	static void pcan_write_canreg(const struct sja1000_priv *priv, int port, u8 v)
	{
	struct pcan_pccard *card = priv->priv;
	int c = (priv->reg_base - card->ioport_addr) / PCC_CHAN_SIZE;

	/* sja1000 register changes control the leds state */
	if (port == REG_MOD)
	switch (v) {
	case MOD_RM:
	/* Reset Mode: set led on */
	pcan_set_leds(card, PCC_LED(c), PCC_LED_ON);
	break;
	case 0x00:
	/* Normal Mode: led slow blinking and start led timer */
	pcan_set_leds(card, PCC_LED(c), PCC_LED_SLOW);
	pcan_start_led_timer(card);
	break;
	default:
	break;
	}

	iowrite8(v, priv->reg_base + port);
	}

	/*
	* read a register from the common area
	*/
	static u8 pcan_read_reg(struct pcan_pccard *card, int port)
	{
	return ioread8(card->ioport_addr + PCC_COMN_OFF + port);
	}

	/*
	* write a register into the common area
	*/
	static void pcan_write_reg(struct pcan_pccard *card, int port, u8 v)
	{
	/* cache ccr value */
	if (port == PCC_CCR) {
	if (card->ccr == v)
	return;
	card->ccr = v;
	}

	iowrite8(v, card->ioport_addr + PCC_COMN_OFF + port);
	}

	/*
	* check whether the card is present by checking its fw version numbers
	* against values read at probing time.
	*/
	static inline int pcan_pccard_present(struct pcan_pccard *card)
	{
	return ((pcan_read_reg(card, PCC_FW_MAJOR) == card->fw_major) &&
	(pcan_read_reg(card, PCC_FW_MINOR) == card->fw_minor));
	}

	/*
	* wait for SPI engine while it is busy
	*/
	static int pcan_wait_spi_busy(struct pcan_pccard *card)
	{
	unsigned long timeout = jiffies +
	msecs_to_jiffies(PCC_SPI_MAX_BUSY_WAIT_MS) + 1;

	/* be sure to read status at least once after sleeping */
	while (pcan_read_reg(card, PCC_CSR) & PCC_CSR_SPI_BUSY) {
	if (time_after(jiffies, timeout))
	return -EBUSY;
	schedule();
	}

	return 0;
	}

	/*
	* write data in device eeprom
	*/
	static int pcan_write_eeprom(struct pcan_pccard *card, u16 addr, u8 v)
	{
	u8 status;
	int err, i;

	/* write instruction enabling write */
	pcan_write_reg(card, PCC_SPI_IR, PCC_EEP_WREN);
	err = pcan_wait_spi_busy(card);
	if (err)
	goto we_spi_err;

	/* wait until write enabled */
	for (i = 0; i < PCC_WRITE_MAX_LOOP; i++) {
	/* write instruction reading the status register */
	pcan_write_reg(card, PCC_SPI_IR, PCC_EEP_RDSR);
	err = pcan_wait_spi_busy(card);
	if (err)
	goto we_spi_err;

	/* get status register value and check write enable bit */
	status = pcan_read_reg(card, PCC_SPI_DIR);
	if (status & PCC_EEP_SR_WEN)
	break;
	}

	if (i >= PCC_WRITE_MAX_LOOP) {
	dev_err(&card->pdev->dev,
	"stop waiting to be allowed to write in eeprom\n");
	return -EIO;
	}

	/* set address and data */
	pcan_write_reg(card, PCC_SPI_ADR, addr & 0xff);
	pcan_write_reg(card, PCC_SPI_DOR, v);

	/*
	* write instruction with bit[3] set according to address value:
	* if addr refers to upper half of the memory array: bit[3] = 1
	*/
	pcan_write_reg(card, PCC_SPI_IR, PCC_EEP_WRITE(addr));
	err = pcan_wait_spi_busy(card);
	if (err)
	goto we_spi_err;

	/* wait while write in progress */
	for (i = 0; i < PCC_WRITE_MAX_LOOP; i++) {
	/* write instruction reading the status register */
	pcan_write_reg(card, PCC_SPI_IR, PCC_EEP_RDSR);
	err = pcan_wait_spi_busy(card);
	if (err)
	goto we_spi_err;

	/* get status register value and check write in progress bit */
	status = pcan_read_reg(card, PCC_SPI_DIR);
	if (!(status & PCC_EEP_SR_WIP))
	break;
	}

	if (i >= PCC_WRITE_MAX_LOOP) {
	dev_err(&card->pdev->dev,
	"stop waiting for write in eeprom to complete\n");
	return -EIO;
	}

	/* write instruction disabling write */
	pcan_write_reg(card, PCC_SPI_IR, PCC_EEP_WRDI);
	err = pcan_wait_spi_busy(card);
	if (err)
	goto we_spi_err;

	return 0;

	we_spi_err:
	dev_err(&card->pdev->dev,
	"stop waiting (spi engine always busy) err %d\n", err);

	return err;
	}

	static void pcan_set_leds(struct pcan_pccard *card, u8 led_mask, u8 state)
	{
	u8 ccr = card->ccr;
	int i;

	for (i = 0; i < card->chan_count; i++)
	if (led_mask & PCC_LED(i)) {
	/* clear corresponding led bits in ccr */
	ccr &= ~PCC_CCR_LED_MASK_CHAN(i);
	/* then set new bits */
	ccr \|= PCC_CCR_LED_CHAN(state, i);
	}

	/* real write only if something has changed in ccr */
	pcan_write_reg(card, PCC_CCR, ccr);
	}

	/*
	* enable/disable CAN connectors power
	*/
	static inline void pcan_set_can_power(struct pcan_pccard *card, int onoff)
	{
	int err;

	err = pcan_write_eeprom(card, 0, !!onoff);
	if (err)
	dev_err(&card->pdev->dev,
	"failed setting power %s to can connectors (err %d)\n",
	(onoff) ? "on" : "off", err);
	}

	/*
	* set leds state according to channel activity
	*/
	static void pcan_led_timer(unsigned long arg)
	{
	struct pcan_pccard card = (struct pcan_pccard )arg;
	struct net_device *netdev;
	int i, up_count = 0;
	u8 ccr;

	ccr = card->ccr;
	for (i = 0; i < card->chan_count; i++) {
	/* default is: not configured */
	ccr &= ~PCC_CCR_LED_MASK_CHAN(i);
	ccr \|= PCC_CCR_LED_ON_CHAN(i);

	netdev = card->channel[i].netdev;
	if (!netdev \|\| !(netdev->flags & IFF_UP))
	continue;

	up_count++;

	/* no activity (but configured) */
	ccr &= ~PCC_CCR_LED_MASK_CHAN(i);
	ccr \|= PCC_CCR_LED_SLOW_CHAN(i);

	/* if bytes counters changed, set fast blinking led */
	if (netdev->stats.rx_bytes != card->channel[i].prev_rx_bytes) {
	card->channel[i].prev_rx_bytes = netdev->stats.rx_bytes;
	ccr &= ~PCC_CCR_LED_MASK_CHAN(i);
	ccr \|= PCC_CCR_LED_FAST_CHAN(i);
	}
	if (netdev->stats.tx_bytes != card->channel[i].prev_tx_bytes) {
	card->channel[i].prev_tx_bytes = netdev->stats.tx_bytes;
	ccr &= ~PCC_CCR_LED_MASK_CHAN(i);
	ccr \|= PCC_CCR_LED_FAST_CHAN(i);
	}
	}

	/* write the new leds state */
	pcan_write_reg(card, PCC_CCR, ccr);

	/* restart timer (except if no more configured channels) */
	if (up_count)
	mod_timer(&card->led_timer, jiffies + HZ);
	}

	/*
	* interrupt service routine
	*/
	static irqreturn_t pcan_isr(int irq, void *dev_id)
	{
	struct pcan_pccard *card = dev_id;
	int irq_handled;

	/* prevent from infinite loop */
	for (irq_handled = 0; irq_handled < PCC_ISR_MAX_LOOP; irq_handled++) {
	/* handle shared interrupt and next loop */
	int nothing_to_handle = 1;
	int i;

	/* check interrupt for each channel */
	for (i = 0; i < card->chan_count; i++) {
	struct net_device *netdev;

	/*
	* check whether the card is present before calling
	* sja1000_interrupt() to speed up hotplug detection
	*/
	if (!pcan_pccard_present(card)) {
	/* card unplugged during isr */
	return IRQ_NONE;
	}

	/*
	* should check whether all or SJA1000_MAX_IRQ
	* interrupts have been handled: loop again to be sure.
	*/
	netdev = card->channel[i].netdev;
	if (netdev &&
	sja1000_interrupt(irq, netdev) == IRQ_HANDLED)
	nothing_to_handle = 0;
	}

	if (nothing_to_handle)
	break;
	}

	return (irq_handled) ? IRQ_HANDLED : IRQ_NONE;
	}

	/*
	* free all resources used by the channels and switch off leds and can power
	*/
	static void pcan_free_channels(struct pcan_pccard *card)
	{
	int i;
	u8 led_mask = 0;

	for (i = 0; i < card->chan_count; i++) {
	struct net_device *netdev;
	char name[IFNAMSIZ];

	led_mask \|= PCC_LED(i);

	netdev = card->channel[i].netdev;
	if (!netdev)
	continue;

	strncpy(name, netdev->name, IFNAMSIZ);

	unregister_sja1000dev(netdev);

	free_sja1000dev(netdev);

	dev_info(&card->pdev->dev, "%s removed\n", name);
	}

	/* do it only if device not removed */
	if (pcan_pccard_present(card)) {
	pcan_set_leds(card, led_mask, PCC_LED_OFF);
	pcan_set_can_power(card, 0);
	}
	}

	/*
	* check if a CAN controller is present at the specified location
	*/
	static inline int pcan_channel_present(struct sja1000_priv *priv)
	{
	/* make sure SJA1000 is in reset mode */
	pcan_write_canreg(priv, REG_MOD, 1);
	pcan_write_canreg(priv, REG_CDR, CDR_PELICAN);

	/* read reset-values */
	if (pcan_read_canreg(priv, REG_CDR) == CDR_PELICAN)
	return 1;

	return 0;
	}

	static int pcan_add_channels(struct pcan_pccard *card)
	{
	struct pcmcia_device *pdev = card->pdev;
	int i, err = 0;
	u8 ccr = PCC_CCR_INIT;

	/* init common registers (reset channels and leds off) */
	card->ccr = ~ccr;
	pcan_write_reg(card, PCC_CCR, ccr);

	/* wait 2ms before unresetting channels */
	mdelay(2);

	ccr &= ~PCC_CCR_RST_ALL;
	pcan_write_reg(card, PCC_CCR, ccr);

	/* create one network device per channel detected */
	for (i = 0; i < ARRAY_SIZE(card->channel); i++) {
	struct net_device *netdev;
	struct sja1000_priv *priv;

	netdev = alloc_sja1000dev(0);
	if (!netdev) {
	err = -ENOMEM;
	break;
	}

	/* update linkages */
	priv = netdev_priv(netdev);
	priv->priv = card;
	SET_NETDEV_DEV(netdev, &pdev->dev);

	priv->irq_flags = IRQF_SHARED;
	netdev->irq = pdev->irq;
	priv->reg_base = card->ioport_addr + PCC_CHAN_OFF(i);

	/* check if channel is present */
	if (!pcan_channel_present(priv)) {
	dev_err(&pdev->dev, "channel %d not present\n", i);
	free_sja1000dev(netdev);
	continue;
	}

	priv->read_reg = pcan_read_canreg;
	priv->write_reg = pcan_write_canreg;
	priv->can.clock.freq = PCC_CAN_CLOCK;
	priv->ocr = PCC_OCR;
	priv->cdr = PCC_CDR;

	/* Neither a slave device distributes the clock */
	if (i > 0)
	priv->cdr \|= CDR_CLK_OFF;

	priv->flags \|= SJA1000_CUSTOM_IRQ_HANDLER;

	/* register SJA1000 device */
	err = register_sja1000dev(netdev);
	if (err) {
	free_sja1000dev(netdev);
	continue;
	}

	card->channel[i].netdev = netdev;
	card->chan_count++;

	/* set corresponding led on in the new ccr */
	ccr &= ~PCC_CCR_LED_OFF_CHAN(i);

	dev_info(&pdev->dev,
	"%s on channel %d at 0x%p irq %d\n",
	netdev->name, i, priv->reg_base, pdev->irq);
	}

	/* write new ccr (change leds state) */
	pcan_write_reg(card, PCC_CCR, ccr);

	return err;
	}

	static int pcan_conf_check(struct pcmcia_device pdev, void priv_data)
	{
	pdev->resource[0]->flags &= ~IO_DATA_PATH_WIDTH;
	pdev->resource[0]->flags \|= IO_DATA_PATH_WIDTH_8; /* only */
	pdev->io_lines = 10;

	/* This reserves IO space but doesn't actually enable it */
	return pcmcia_request_io(pdev);
	}

	/*
	* free all resources used by the device
	*/
	static void pcan_free(struct pcmcia_device *pdev)
	{
	struct pcan_pccard *card = pdev->priv;

	if (!card)
	return;

	free_irq(pdev->irq, card);
	pcan_stop_led_timer(card);

	pcan_free_channels(card);

	ioport_unmap(card->ioport_addr);

	kfree(card);
	pdev->priv = NULL;
	}

	/*
	* setup PCMCIA socket and probe for PEAK-System PC-CARD
	*/
	static int pcan_probe(struct pcmcia_device *pdev)
	{
	struct pcan_pccard *card;
	int err;

	pdev->config_flags \|= CONF_ENABLE_IRQ \| CONF_AUTO_SET_IO;

	err = pcmcia_loop_config(pdev, pcan_conf_check, NULL);
	if (err) {
	dev_err(&pdev->dev, "pcmcia_loop_config() error %d\n", err);
	goto probe_err_1;
	}

	if (!pdev->irq) {
	dev_err(&pdev->dev, "no irq assigned\n");
	err = -ENODEV;
	goto probe_err_1;
	}

	err = pcmcia_enable_device(pdev);
	if (err) {
	dev_err(&pdev->dev, "pcmcia_enable_device failed err=%d\n",
	err);
	goto probe_err_1;
	}

	card = kzalloc(sizeof(struct pcan_pccard), GFP_KERNEL);
	if (!card) {
	err = -ENOMEM;
	goto probe_err_2;
	}

	card->pdev = pdev;
	pdev->priv = card;

	/* sja1000 api uses iomem */
	card->ioport_addr = ioport_map(pdev->resource[0]->start,
	resource_size(pdev->resource[0]));
	if (!card->ioport_addr) {
	dev_err(&pdev->dev, "couldn't map io port into io memory\n");
	err = -ENOMEM;
	goto probe_err_3;
	}
	card->fw_major = pcan_read_reg(card, PCC_FW_MAJOR);
	card->fw_minor = pcan_read_reg(card, PCC_FW_MINOR);

	/* display board name and firware version */
	dev_info(&pdev->dev, "PEAK-System pcmcia card %s fw %d.%d\n",
	pdev->prod_id[1] ? pdev->prod_id[1] : "PCAN-PC Card",
	card->fw_major, card->fw_minor);

	/* detect available channels */
	pcan_add_channels(card);
	if (!card->chan_count) {
	err = -ENOMEM;
	goto probe_err_4;
	}

	/* init the timer which controls the leds */
	init_timer(&card->led_timer);
	card->led_timer.function = pcan_led_timer;
	card->led_timer.data = (unsigned long)card;

	/* request the given irq */
	err = request_irq(pdev->irq, &pcan_isr, IRQF_SHARED, PCC_NAME, card);
	if (err) {
	dev_err(&pdev->dev, "couldn't request irq%d\n", pdev->irq);
	goto probe_err_5;
	}

	/* power on the connectors */
	pcan_set_can_power(card, 1);

	return 0;

	probe_err_5:
	/* unregister can devices from network */
	pcan_free_channels(card);

	probe_err_4:
	ioport_unmap(card->ioport_addr);

	probe_err_3:
	kfree(card);
	pdev->priv = NULL;

	probe_err_2:
	pcmcia_disable_device(pdev);

	probe_err_1:
	return err;
	}

	/*
	* release claimed resources
	*/
	static void pcan_remove(struct pcmcia_device *pdev)
	{
	pcan_free(pdev);
	pcmcia_disable_device(pdev);
	}

	static struct pcmcia_driver pcan_driver = {
	.name = PCC_NAME,
	.probe = pcan_probe,
	.remove = pcan_remove,
	.id_table = pcan_table,
	};

	static int __init pcan_init(void)
	{
	return pcmcia_register_driver(&pcan_driver);
	}
	module_init(pcan_init);

	static void __exit pcan_exit(void)
	{
	pcmcia_unregister_driver(&pcan_driver);
	}
	module_exit(pcan_exit);