drivers/net/can/sja1000/ems_pcmcia.c - linux - Git at Google

 /*
  * 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, 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);
 	}

 	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 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);
	/*
	* 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, 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);
	}

	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 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);