drivers/net/can/cc770/cc770_isa.c - kernel/msm-4.19 - Gitiles

 /*
  * Driver for CC770 and AN82527 CAN controllers on the legacy ISA bus
  *
  * Copyright (C) 2009, 2011 Wolfgang Grandegger <wg@grandegger.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.
  */

 /*
  * Bosch CC770 and Intel AN82527 CAN controllers on the ISA or PC-104 bus.
  * The I/O port or memory address and the IRQ number must be specified via
  * module parameters:
  *
  *   insmod cc770_isa.ko port=0x310,0x380 irq=7,11
  *
  * for ISA devices using I/O ports or:
  *
  *   insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11
  *
  * for memory mapped ISA devices.
  *
  * Indirect access via address and data port is supported as well:
  *
  *   insmod cc770_isa.ko port=0x310,0x380 indirect=1 irq=7,11
  *
  * Furthermore, the following mode parameter can be defined:
  *
  *   clk: External oscillator clock frequency (default=16000000 [16 MHz])
  *   cir: CPU interface register (default=0x40 [DSC])
  *   bcr: Bus configuration register (default=0x40 [CBY])
  *   cor: Clockout register (default=0x00)
  *
  * Note: for clk, cir, bcr and cor, the first argument re-defines the
  * default for all other devices, e.g.:
  *
  *   insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 clk=24000000
  *
  * is equivalent to
  *
  *   insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 clk=24000000,24000000
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
 #include <linux/netdevice.h>
 #include <linux/delay.h>
 #include <linux/irq.h>
 #include <linux/io.h>
 #include <linux/can.h>
 #include <linux/can/dev.h>
 #include <linux/can/platform/cc770.h>

 #include "cc770.h"

 #define MAXDEV 8

 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
 MODULE_DESCRIPTION("Socket-CAN driver for CC770 on the ISA bus");
 MODULE_LICENSE("GPL v2");

 #define CLK_DEFAULT	16000000	/* 16 MHz */
 #define COR_DEFAULT	0x00
 #define BCR_DEFAULT	BUSCFG_CBY

 static unsigned long port[MAXDEV];
 static unsigned long mem[MAXDEV];
 static int __devinitdata irq[MAXDEV];
 static int __devinitdata clk[MAXDEV];
 static u8 __devinitdata cir[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
 static u8 __devinitdata cor[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
 static u8 __devinitdata bcr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
 static int __devinitdata indirect[MAXDEV] = {[0 ... (MAXDEV - 1)] = -1};

 module_param_array(port, ulong, NULL, S_IRUGO);
 MODULE_PARM_DESC(port, "I/O port number");

 module_param_array(mem, ulong, NULL, S_IRUGO);
 MODULE_PARM_DESC(mem, "I/O memory address");

 module_param_array(indirect, int, NULL, S_IRUGO);
 MODULE_PARM_DESC(indirect, "Indirect access via address and data port");

 module_param_array(irq, int, NULL, S_IRUGO);
 MODULE_PARM_DESC(irq, "IRQ number");

 module_param_array(clk, int, NULL, S_IRUGO);
 MODULE_PARM_DESC(clk, "External oscillator clock frequency "
 		 "(default=16000000 [16 MHz])");

 module_param_array(cir, byte, NULL, S_IRUGO);
 MODULE_PARM_DESC(cir, "CPU interface register (default=0x40 [DSC])");

 module_param_array(cor, byte, NULL, S_IRUGO);
 MODULE_PARM_DESC(cor, "Clockout register (default=0x00)");

 module_param_array(bcr, byte, NULL, S_IRUGO);
 MODULE_PARM_DESC(bcr, "Bus configuration register (default=0x40 [CBY])");

 #define CC770_IOSIZE          0x20
 #define CC770_IOSIZE_INDIRECT 0x02

 static struct platform_device *cc770_isa_devs[MAXDEV];

 static u8 cc770_isa_mem_read_reg(const struct cc770_priv *priv, int reg)
 {
 	return readb(priv->reg_base + reg);
 }

 static void cc770_isa_mem_write_reg(const struct cc770_priv *priv,
 				      int reg, u8 val)
 {
 	writeb(val, priv->reg_base + reg);
 }

 static u8 cc770_isa_port_read_reg(const struct cc770_priv *priv, int reg)
 {
 	return inb((unsigned long)priv->reg_base + reg);
 }

 static void cc770_isa_port_write_reg(const struct cc770_priv *priv,
 				       int reg, u8 val)
 {
 	outb(val, (unsigned long)priv->reg_base + reg);
 }

 static u8 cc770_isa_port_read_reg_indirect(const struct cc770_priv *priv,
 					     int reg)
 {
 	unsigned long base = (unsigned long)priv->reg_base;

 	outb(reg, base);
 	return inb(base + 1);
 }

 static void cc770_isa_port_write_reg_indirect(const struct cc770_priv *priv,
 						int reg, u8 val)
 {
 	unsigned long base = (unsigned long)priv->reg_base;

 	outb(reg, base);
 	outb(val, base + 1);
 }

 static int __devinit cc770_isa_probe(struct platform_device *pdev)
 {
 	struct net_device *dev;
 	struct cc770_priv *priv;
 	void __iomem *base = NULL;
 	int iosize = CC770_IOSIZE;
 	int idx = pdev->id;
 	int err;
 	u32 clktmp;

 	dev_dbg(&pdev->dev, "probing idx=%d: port=%#lx, mem=%#lx, irq=%d\n",
 		idx, port[idx], mem[idx], irq[idx]);
 	if (mem[idx]) {
 		if (!request_mem_region(mem[idx], iosize, KBUILD_MODNAME)) {
 			err = -EBUSY;
 			goto exit;
 		}
 		base = ioremap_nocache(mem[idx], iosize);
 		if (!base) {
 			err = -ENOMEM;
 			goto exit_release;
 		}
 	} else {
 		if (indirect[idx] > 0 ||
 		    (indirect[idx] == -1 && indirect[0] > 0))
 			iosize = CC770_IOSIZE_INDIRECT;
 		if (!request_region(port[idx], iosize, KBUILD_MODNAME)) {
 			err = -EBUSY;
 			goto exit;
 		}
 	}

 	dev = alloc_cc770dev(0);
 	if (!dev) {
 		err = -ENOMEM;
 		goto exit_unmap;
 	}
 	priv = netdev_priv(dev);

 	dev->irq = irq[idx];
 	priv->irq_flags = IRQF_SHARED;
 	if (mem[idx]) {
 		priv->reg_base = base;
 		dev->base_addr = mem[idx];
 		priv->read_reg = cc770_isa_mem_read_reg;
 		priv->write_reg = cc770_isa_mem_write_reg;
 	} else {
 		priv->reg_base = (void __iomem *)port[idx];
 		dev->base_addr = port[idx];

 		if (iosize == CC770_IOSIZE_INDIRECT) {
 			priv->read_reg = cc770_isa_port_read_reg_indirect;
 			priv->write_reg = cc770_isa_port_write_reg_indirect;
 		} else {
 			priv->read_reg = cc770_isa_port_read_reg;
 			priv->write_reg = cc770_isa_port_write_reg;
 		}
 	}

 	if (clk[idx])
 		clktmp = clk[idx];
 	else if (clk[0])
 		clktmp = clk[0];
 	else
 		clktmp = CLK_DEFAULT;
 	priv->can.clock.freq = clktmp;

 	if (cir[idx] != 0xff) {
 		priv->cpu_interface = cir[idx];
 	} else if (cir[0] != 0xff) {
 		priv->cpu_interface = cir[0];
 	} else {
 		/* The system clock may not exceed 10 MHz */
 		if (clktmp > 10000000) {
 			priv->cpu_interface |= CPUIF_DSC;
 			clktmp /= 2;
 		}
 		/* The memory clock may not exceed 8 MHz */
 		if (clktmp > 8000000)
 			priv->cpu_interface |= CPUIF_DMC;
 	}

 	if (priv->cpu_interface & CPUIF_DSC)
 		priv->can.clock.freq /= 2;

 	if (bcr[idx] != 0xff)
 		priv->bus_config = bcr[idx];
 	else if (bcr[0] != 0xff)
 		priv->bus_config = bcr[0];
 	else
 		priv->bus_config = BCR_DEFAULT;

 	if (cor[idx] != 0xff)
 		priv->clkout = cor[idx];
 	else if (cor[0] != 0xff)
 		priv->clkout = cor[0];
 	else
 		priv->clkout = COR_DEFAULT;

 	dev_set_drvdata(&pdev->dev, dev);
 	SET_NETDEV_DEV(dev, &pdev->dev);

 	err = register_cc770dev(dev);
 	if (err) {
 		dev_err(&pdev->dev,
 			"couldn't register device (err=%d)\n", err);
 		goto exit_unmap;
 	}

 	dev_info(&pdev->dev, "device registered (reg_base=0x%p, irq=%d)\n",
 		 priv->reg_base, dev->irq);
 	return 0;

  exit_unmap:
 	if (mem[idx])
 		iounmap(base);
  exit_release:
 	if (mem[idx])
 		release_mem_region(mem[idx], iosize);
 	else
 		release_region(port[idx], iosize);
  exit:
 	return err;
 }

 static int __devexit cc770_isa_remove(struct platform_device *pdev)
 {
 	struct net_device *dev = dev_get_drvdata(&pdev->dev);
 	struct cc770_priv *priv = netdev_priv(dev);
 	int idx = pdev->id;

 	unregister_cc770dev(dev);
 	dev_set_drvdata(&pdev->dev, NULL);

 	if (mem[idx]) {
 		iounmap(priv->reg_base);
 		release_mem_region(mem[idx], CC770_IOSIZE);
 	} else {
 		if (priv->read_reg == cc770_isa_port_read_reg_indirect)
 			release_region(port[idx], CC770_IOSIZE_INDIRECT);
 		else
 			release_region(port[idx], CC770_IOSIZE);
 	}
 	free_cc770dev(dev);

 	return 0;
 }

 static struct platform_driver cc770_isa_driver = {
 	.probe = cc770_isa_probe,
 	.remove = __devexit_p(cc770_isa_remove),
 	.driver = {
 		.name = KBUILD_MODNAME,
 		.owner = THIS_MODULE,
 	},
 };

 static int __init cc770_isa_init(void)
 {
 	int idx, err;

 	for (idx = 0; idx < ARRAY_SIZE(cc770_isa_devs); idx++) {
 		if ((port[idx] || mem[idx]) && irq[idx]) {
 			cc770_isa_devs[idx] =
 				platform_device_alloc(KBUILD_MODNAME, idx);
 			if (!cc770_isa_devs[idx]) {
 				err = -ENOMEM;
 				goto exit_free_devices;
 			}
 			err = platform_device_add(cc770_isa_devs[idx]);
 			if (err) {
 				platform_device_put(cc770_isa_devs[idx]);
 				goto exit_free_devices;
 			}
 			pr_debug("platform device %d: port=%#lx, mem=%#lx, "
 				 "irq=%d\n",
 				 idx, port[idx], mem[idx], irq[idx]);
 		} else if (idx == 0 || port[idx] || mem[idx]) {
 			pr_err("insufficient parameters supplied\n");
 			err = -EINVAL;
 			goto exit_free_devices;
 		}
 	}

 	err = platform_driver_register(&cc770_isa_driver);
 	if (err)
 		goto exit_free_devices;

 	pr_info("driver for max. %d devices registered\n", MAXDEV);

 	return 0;

 exit_free_devices:
 	while (--idx >= 0) {
 		if (cc770_isa_devs[idx])
 			platform_device_unregister(cc770_isa_devs[idx]);
 	}

 	return err;
 }
 module_init(cc770_isa_init);

 static void __exit cc770_isa_exit(void)
 {
 	int idx;

 	platform_driver_unregister(&cc770_isa_driver);
 	for (idx = 0; idx < ARRAY_SIZE(cc770_isa_devs); idx++) {
 		if (cc770_isa_devs[idx])
 			platform_device_unregister(cc770_isa_devs[idx]);
 	}
 }
 module_exit(cc770_isa_exit);
	/*
	* Driver for CC770 and AN82527 CAN controllers on the legacy ISA bus
	*
	* Copyright (C) 2009, 2011 Wolfgang Grandegger <wg@grandegger.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.
	*/

	/*
	* Bosch CC770 and Intel AN82527 CAN controllers on the ISA or PC-104 bus.
	* The I/O port or memory address and the IRQ number must be specified via
	* module parameters:
	*
	* insmod cc770_isa.ko port=0x310,0x380 irq=7,11
	*
	* for ISA devices using I/O ports or:
	*
	* insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11
	*
	* for memory mapped ISA devices.
	*
	* Indirect access via address and data port is supported as well:
	*
	* insmod cc770_isa.ko port=0x310,0x380 indirect=1 irq=7,11
	*
	* Furthermore, the following mode parameter can be defined:
	*
	* clk: External oscillator clock frequency (default=16000000 [16 MHz])
	* cir: CPU interface register (default=0x40 [DSC])
	* bcr: Bus configuration register (default=0x40 [CBY])
	* cor: Clockout register (default=0x00)
	*
	* Note: for clk, cir, bcr and cor, the first argument re-defines the
	* default for all other devices, e.g.:
	*
	* insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 clk=24000000
	*
	* is equivalent to
	*
	* insmod cc770_isa.ko mem=0xd1000,0xd1000 irq=7,11 clk=24000000,24000000
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/interrupt.h>
	#include <linux/netdevice.h>
	#include <linux/delay.h>
	#include <linux/irq.h>
	#include <linux/io.h>
	#include <linux/can.h>
	#include <linux/can/dev.h>
	#include <linux/can/platform/cc770.h>

	#include "cc770.h"

	#define MAXDEV 8

	MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
	MODULE_DESCRIPTION("Socket-CAN driver for CC770 on the ISA bus");
	MODULE_LICENSE("GPL v2");

	#define CLK_DEFAULT 16000000 /* 16 MHz */
	#define COR_DEFAULT 0x00
	#define BCR_DEFAULT BUSCFG_CBY

	static unsigned long port[MAXDEV];
	static unsigned long mem[MAXDEV];
	static int __devinitdata irq[MAXDEV];
	static int __devinitdata clk[MAXDEV];
	static u8 __devinitdata cir[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
	static u8 __devinitdata cor[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
	static u8 __devinitdata bcr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
	static int __devinitdata indirect[MAXDEV] = {[0 ... (MAXDEV - 1)] = -1};

	module_param_array(port, ulong, NULL, S_IRUGO);
	MODULE_PARM_DESC(port, "I/O port number");

	module_param_array(mem, ulong, NULL, S_IRUGO);
	MODULE_PARM_DESC(mem, "I/O memory address");

	module_param_array(indirect, int, NULL, S_IRUGO);
	MODULE_PARM_DESC(indirect, "Indirect access via address and data port");

	module_param_array(irq, int, NULL, S_IRUGO);
	MODULE_PARM_DESC(irq, "IRQ number");

	module_param_array(clk, int, NULL, S_IRUGO);
	MODULE_PARM_DESC(clk, "External oscillator clock frequency "
	"(default=16000000 [16 MHz])");

	module_param_array(cir, byte, NULL, S_IRUGO);
	MODULE_PARM_DESC(cir, "CPU interface register (default=0x40 [DSC])");

	module_param_array(cor, byte, NULL, S_IRUGO);
	MODULE_PARM_DESC(cor, "Clockout register (default=0x00)");

	module_param_array(bcr, byte, NULL, S_IRUGO);
	MODULE_PARM_DESC(bcr, "Bus configuration register (default=0x40 [CBY])");

	#define CC770_IOSIZE 0x20
	#define CC770_IOSIZE_INDIRECT 0x02

	static struct platform_device *cc770_isa_devs[MAXDEV];

	static u8 cc770_isa_mem_read_reg(const struct cc770_priv *priv, int reg)
	{
	return readb(priv->reg_base + reg);
	}

	static void cc770_isa_mem_write_reg(const struct cc770_priv *priv,
	int reg, u8 val)
	{
	writeb(val, priv->reg_base + reg);
	}

	static u8 cc770_isa_port_read_reg(const struct cc770_priv *priv, int reg)
	{
	return inb((unsigned long)priv->reg_base + reg);
	}

	static void cc770_isa_port_write_reg(const struct cc770_priv *priv,
	int reg, u8 val)
	{
	outb(val, (unsigned long)priv->reg_base + reg);
	}

	static u8 cc770_isa_port_read_reg_indirect(const struct cc770_priv *priv,
	int reg)
	{
	unsigned long base = (unsigned long)priv->reg_base;

	outb(reg, base);
	return inb(base + 1);
	}

	static void cc770_isa_port_write_reg_indirect(const struct cc770_priv *priv,
	int reg, u8 val)
	{
	unsigned long base = (unsigned long)priv->reg_base;

	outb(reg, base);
	outb(val, base + 1);
	}

	static int __devinit cc770_isa_probe(struct platform_device *pdev)
	{
	struct net_device *dev;
	struct cc770_priv *priv;
	void __iomem *base = NULL;
	int iosize = CC770_IOSIZE;
	int idx = pdev->id;
	int err;
	u32 clktmp;

	dev_dbg(&pdev->dev, "probing idx=%d: port=%#lx, mem=%#lx, irq=%d\n",
	idx, port[idx], mem[idx], irq[idx]);
	if (mem[idx]) {
	if (!request_mem_region(mem[idx], iosize, KBUILD_MODNAME)) {
	err = -EBUSY;
	goto exit;
	}
	base = ioremap_nocache(mem[idx], iosize);
	if (!base) {
	err = -ENOMEM;
	goto exit_release;
	}
	} else {
	if (indirect[idx] > 0 \|\|
	(indirect[idx] == -1 && indirect[0] > 0))
	iosize = CC770_IOSIZE_INDIRECT;
	if (!request_region(port[idx], iosize, KBUILD_MODNAME)) {
	err = -EBUSY;
	goto exit;
	}
	}

	dev = alloc_cc770dev(0);
	if (!dev) {
	err = -ENOMEM;
	goto exit_unmap;
	}
	priv = netdev_priv(dev);

	dev->irq = irq[idx];
	priv->irq_flags = IRQF_SHARED;
	if (mem[idx]) {
	priv->reg_base = base;
	dev->base_addr = mem[idx];
	priv->read_reg = cc770_isa_mem_read_reg;
	priv->write_reg = cc770_isa_mem_write_reg;
	} else {
	priv->reg_base = (void __iomem *)port[idx];
	dev->base_addr = port[idx];

	if (iosize == CC770_IOSIZE_INDIRECT) {
	priv->read_reg = cc770_isa_port_read_reg_indirect;
	priv->write_reg = cc770_isa_port_write_reg_indirect;
	} else {
	priv->read_reg = cc770_isa_port_read_reg;
	priv->write_reg = cc770_isa_port_write_reg;
	}
	}

	if (clk[idx])
	clktmp = clk[idx];
	else if (clk[0])
	clktmp = clk[0];
	else
	clktmp = CLK_DEFAULT;
	priv->can.clock.freq = clktmp;

	if (cir[idx] != 0xff) {
	priv->cpu_interface = cir[idx];
	} else if (cir[0] != 0xff) {
	priv->cpu_interface = cir[0];
	} else {
	/* The system clock may not exceed 10 MHz */
	if (clktmp > 10000000) {
	priv->cpu_interface \|= CPUIF_DSC;
	clktmp /= 2;
	}
	/* The memory clock may not exceed 8 MHz */
	if (clktmp > 8000000)
	priv->cpu_interface \|= CPUIF_DMC;
	}

	if (priv->cpu_interface & CPUIF_DSC)
	priv->can.clock.freq /= 2;

	if (bcr[idx] != 0xff)
	priv->bus_config = bcr[idx];
	else if (bcr[0] != 0xff)
	priv->bus_config = bcr[0];
	else
	priv->bus_config = BCR_DEFAULT;

	if (cor[idx] != 0xff)
	priv->clkout = cor[idx];
	else if (cor[0] != 0xff)
	priv->clkout = cor[0];
	else
	priv->clkout = COR_DEFAULT;

	dev_set_drvdata(&pdev->dev, dev);
	SET_NETDEV_DEV(dev, &pdev->dev);

	err = register_cc770dev(dev);
	if (err) {
	dev_err(&pdev->dev,
	"couldn't register device (err=%d)\n", err);
	goto exit_unmap;
	}

	dev_info(&pdev->dev, "device registered (reg_base=0x%p, irq=%d)\n",
	priv->reg_base, dev->irq);
	return 0;

	exit_unmap:
	if (mem[idx])
	iounmap(base);
	exit_release:
	if (mem[idx])
	release_mem_region(mem[idx], iosize);
	else
	release_region(port[idx], iosize);
	exit:
	return err;
	}

	static int __devexit cc770_isa_remove(struct platform_device *pdev)
	{
	struct net_device *dev = dev_get_drvdata(&pdev->dev);
	struct cc770_priv *priv = netdev_priv(dev);
	int idx = pdev->id;

	unregister_cc770dev(dev);
	dev_set_drvdata(&pdev->dev, NULL);

	if (mem[idx]) {
	iounmap(priv->reg_base);
	release_mem_region(mem[idx], CC770_IOSIZE);
	} else {
	if (priv->read_reg == cc770_isa_port_read_reg_indirect)
	release_region(port[idx], CC770_IOSIZE_INDIRECT);
	else
	release_region(port[idx], CC770_IOSIZE);
	}
	free_cc770dev(dev);

	return 0;
	}

	static struct platform_driver cc770_isa_driver = {
	.probe = cc770_isa_probe,
	.remove = __devexit_p(cc770_isa_remove),
	.driver = {
	.name = KBUILD_MODNAME,
	.owner = THIS_MODULE,
	},
	};

	static int __init cc770_isa_init(void)
	{
	int idx, err;

	for (idx = 0; idx < ARRAY_SIZE(cc770_isa_devs); idx++) {
	if ((port[idx] \|\| mem[idx]) && irq[idx]) {
	cc770_isa_devs[idx] =
	platform_device_alloc(KBUILD_MODNAME, idx);
	if (!cc770_isa_devs[idx]) {
	err = -ENOMEM;
	goto exit_free_devices;
	}
	err = platform_device_add(cc770_isa_devs[idx]);
	if (err) {
	platform_device_put(cc770_isa_devs[idx]);
	goto exit_free_devices;
	}
	pr_debug("platform device %d: port=%#lx, mem=%#lx, "
	"irq=%d\n",
	idx, port[idx], mem[idx], irq[idx]);
	} else if (idx == 0 \|\| port[idx] \|\| mem[idx]) {
	pr_err("insufficient parameters supplied\n");
	err = -EINVAL;
	goto exit_free_devices;
	}
	}

	err = platform_driver_register(&cc770_isa_driver);
	if (err)
	goto exit_free_devices;

	pr_info("driver for max. %d devices registered\n", MAXDEV);

	return 0;

	exit_free_devices:
	while (--idx >= 0) {
	if (cc770_isa_devs[idx])
	platform_device_unregister(cc770_isa_devs[idx]);
	}

	return err;
	}
	module_init(cc770_isa_init);

	static void __exit cc770_isa_exit(void)
	{
	int idx;

	platform_driver_unregister(&cc770_isa_driver);
	for (idx = 0; idx < ARRAY_SIZE(cc770_isa_devs); idx++) {
	if (cc770_isa_devs[idx])
	platform_device_unregister(cc770_isa_devs[idx]);
	}
	}
	module_exit(cc770_isa_exit);