hwmon: Fix a potential race condition on unload

[linux-2.6-omap-h63xx.git] / drivers / hwmon / f71805f.c

diff --git a/drivers/hwmon/f71805f.c b/drivers/hwmon/f71805f.c
index 7c2973487122cd139b22081225cbcbefefa28bae..8fe4d70d8f51148071df253520a0b00e7d5becd0 100644 (file)
--- a/drivers/hwmon/f71805f.c
+++ b/drivers/hwmon/f71805f.c
@@ -35,6 +35,7 @@
 #include <linux/err.h>
 #include <linux/mutex.h>
 #include <linux/sysfs.h>
+#include <linux/ioport.h>
 #include <asm/io.h>
 
 static struct platform_device *pdev;
@@ -1140,6 +1141,13 @@ static int __devinit f71805f_probe(struct platform_device *pdev)
        }
 
        res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+       if (!request_region(res->start + ADDR_REG_OFFSET, 2, DRVNAME)) {
+               err = -EBUSY;
+               dev_err(&pdev->dev, "Failed to request region 0x%lx-0x%lx\n",
+                       (unsigned long)(res->start + ADDR_REG_OFFSET),
+                       (unsigned long)(res->start + ADDR_REG_OFFSET + 1));
+               goto exit_free;
+       }
        data->addr = res->start;
        data->name = names[sio_data->kind];
        mutex_init(&data->update_lock);
@@ -1165,7 +1173,7 @@ static int __devinit f71805f_probe(struct platform_device *pdev)
 
        /* Register sysfs interface files */
        if ((err = sysfs_create_group(&pdev->dev.kobj, &f71805f_group)))
-               goto exit_free;
+               goto exit_release_region;
        if (data->has_in & (1 << 4)) { /* in4 */
                if ((err = sysfs_create_group(&pdev->dev.kobj,
                                              &f71805f_group_optin[0])))
@@ -1219,6 +1227,8 @@ exit_remove_files:
        for (i = 0; i < 4; i++)
                sysfs_remove_group(&pdev->dev.kobj, &f71805f_group_optin[i]);
        sysfs_remove_group(&pdev->dev.kobj, &f71805f_group_pwm_freq);
+exit_release_region:
+       release_region(res->start + ADDR_REG_OFFSET, 2);
 exit_free:
        platform_set_drvdata(pdev, NULL);
        kfree(data);
@@ -1229,16 +1239,20 @@ exit:
 static int __devexit f71805f_remove(struct platform_device *pdev)
 {
        struct f71805f_data *data = platform_get_drvdata(pdev);
+       struct resource *res;
        int i;
 
-       platform_set_drvdata(pdev, NULL);
        hwmon_device_unregister(data->class_dev);
        sysfs_remove_group(&pdev->dev.kobj, &f71805f_group);
        for (i = 0; i < 4; i++)
                sysfs_remove_group(&pdev->dev.kobj, &f71805f_group_optin[i]);
        sysfs_remove_group(&pdev->dev.kobj, &f71805f_group_pwm_freq);
+       platform_set_drvdata(pdev, NULL);
        kfree(data);
 
+       res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+       release_region(res->start + ADDR_REG_OFFSET, 2);
+
        return 0;
 }
 
@@ -1276,15 +1290,12 @@ static int __init f71805f_device_add(unsigned short address,
                goto exit_device_put;
        }
 
-       pdev->dev.platform_data = kmalloc(sizeof(struct f71805f_sio_data),
-                                         GFP_KERNEL);
-       if (!pdev->dev.platform_data) {
-               err = -ENOMEM;
+       err = platform_device_add_data(pdev, sio_data,
+                                      sizeof(struct f71805f_sio_data));
+       if (err) {
                printk(KERN_ERR DRVNAME ": Platform data allocation failed\n");
                goto exit_device_put;
        }
-       memcpy(pdev->dev.platform_data, sio_data,
-              sizeof(struct f71805f_sio_data));
 
        err = platform_device_add(pdev);
        if (err) {