Commit c6e8bb2c authored by Jean Delvare's avatar Jean Delvare Committed by Jean Delvare
Browse files

i2c-parport-light: Port to the new device driver model 



Also fix a small race on driver unload: we need to unregister the
i2c adapter before we power it off.

Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
parent 3af07bd2

drivers/i2c/busses/i2c-parport-light.c

+117 −27
Original line number Diff line number Diff line 
/* ------------------------------------------------------------------------ *

 * i2c-parport.c I2C bus over parallel port                                 *

 * i2c-parport-light.c I2C bus over parallel port                           *

 * ------------------------------------------------------------------------ *

   Copyright (C) 2003-2004 Jean Delvare <khali@linux-fr.org>

   Copyright (C) 2003-2007 Jean Delvare <khali@linux-fr.org>

   

   Based on older i2c-velleman.c driver

   Copyright (C) 1995-2000 Simon G. Vogl
@@ -27,6 +27,7 @@ 
#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/init.h>

#include <linux/platform_device.h>

#include <linux/ioport.h>

#include <linux/i2c.h>

#include <linux/i2c-algo-bit.h>
@@ -34,6 +35,9 @@ 
#include "i2c-parport.h"



#define DEFAULT_BASE 0x378

#define DRVNAME "i2c-parport-light"



static struct platform_device *pdev;



static u16 base;

module_param(base, ushort, 0);
@@ -106,7 +110,7 @@ static struct i2c_algo_bit_data parport_algo_data = { 
	.timeout	= HZ,

}; 



/* ----- I2c structure ---------------------------------------------------- */

/* ----- Driver registration ---------------------------------------------- */



static struct i2c_adapter parport_adapter = {

	.owner		= THIS_MODULE,
@@ -116,55 +120,141 @@ static struct i2c_adapter parport_adapter = { 
	.name		= "Parallel port adapter (light)",

};



/* ----- Module loading, unloading and information ------------------------ */

static int __devinit i2c_parport_probe(struct platform_device *pdev)

{

	int err;

	struct resource *res;



	res = platform_get_resource(pdev, IORESOURCE_IO, 0);

	if (!request_region(res->start, res->end - res->start + 1, DRVNAME))

		return -EBUSY;



	/* Reset hardware to a sane state (SCL and SDA high) */

	parport_setsda(NULL, 1);

	parport_setscl(NULL, 1);

	/* Other init if needed (power on...) */

	if (adapter_parm[type].init.val)

		line_set(1, &adapter_parm[type].init);



	parport_adapter.dev.parent = &pdev->dev;

	err = i2c_bit_add_bus(&parport_adapter);

	if (err) {

		dev_err(&pdev->dev, "Unable to register with I2C\n");

		goto exit_region;

	}

	return 0;



exit_region:

	release_region(res->start, res->end - res->start + 1);

	return err;

}



static int __devexit i2c_parport_remove(struct platform_device *pdev)

{

	struct resource *res;



	i2c_del_adapter(&parport_adapter);



	/* Un-init if needed (power off...) */

	if (adapter_parm[type].init.val)

		line_set(0, &adapter_parm[type].init);



	res = platform_get_resource(pdev, IORESOURCE_IO, 0);

	release_region(res->start, res->end - res->start + 1);

	return 0;

}



static struct platform_driver i2c_parport_driver = {

	.driver = {

		.owner	= THIS_MODULE,

		.name	= DRVNAME,

	},

	.probe		= i2c_parport_probe,

	.remove		= __devexit_p(i2c_parport_remove),

};



static int __init i2c_parport_device_add(u16 address)

{

	struct resource res = {

		.start	= address,

		.end	= address + 2,

		.name	= DRVNAME,

		.flags	= IORESOURCE_IO,

	};

	int err;



	pdev = platform_device_alloc(DRVNAME, -1);

	if (!pdev) {

		err = -ENOMEM;

		printk(KERN_ERR DRVNAME ": Device allocation failed\n");

		goto exit;

	}



	err = platform_device_add_resources(pdev, &res, 1);

	if (err) {

		printk(KERN_ERR DRVNAME ": Device resource addition failed "

		       "(%d)\n", err);

		goto exit_device_put;

	}



	err = platform_device_add(pdev);

	if (err) {

		printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n",

		       err);

		goto exit_device_put;

	}



	return 0;



exit_device_put:

	platform_device_put(pdev);

exit:

	return err;

}



static int __init i2c_parport_init(void)

{

	int err;



	if (type < 0) {

		printk(KERN_WARNING "i2c-parport: adapter type unspecified\n");

		printk(KERN_ERR DRVNAME ": adapter type unspecified\n");

		return -ENODEV;

	}



	if (type >= ARRAY_SIZE(adapter_parm)) {

		printk(KERN_WARNING "i2c-parport: invalid type (%d)\n", type);

		printk(KERN_ERR DRVNAME ": invalid type (%d)\n", type);

		return -ENODEV;

	}



	if (base == 0) {

		printk(KERN_INFO "i2c-parport: using default base 0x%x\n", DEFAULT_BASE);

		pr_info(DRVNAME ": using default base 0x%x\n", DEFAULT_BASE);

		base = DEFAULT_BASE;

	}



	if (!request_region(base, 3, "i2c-parport"))

		return -ENODEV;



        if (!adapter_parm[type].getscl.val)

		parport_algo_data.getscl = NULL;



	/* Reset hardware to a sane state (SCL and SDA high) */

	parport_setsda(NULL, 1);

	parport_setscl(NULL, 1);

	/* Other init if needed (power on...) */

	if (adapter_parm[type].init.val)

		line_set(1, &adapter_parm[type].init);

	/* Sets global pdev as a side effect */

	err = i2c_parport_device_add(base);

	if (err)

		goto exit;



	if (i2c_bit_add_bus(&parport_adapter) < 0) {

		printk(KERN_ERR "i2c-parport: Unable to register with I2C\n");

		release_region(base, 3);

		return -ENODEV;

	}

	err = platform_driver_register(&i2c_parport_driver);

	if (err)

		goto exit_device;



	return 0;



exit_device:

	platform_device_unregister(pdev);

exit:

	return err;

}



static void __exit i2c_parport_exit(void)

{

	/* Un-init if needed (power off...) */

	if (adapter_parm[type].init.val)

		line_set(0, &adapter_parm[type].init);



	i2c_del_adapter(&parport_adapter);

	release_region(base, 3);

	platform_driver_unregister(&i2c_parport_driver);

	platform_device_unregister(pdev);

}



MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");

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