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hwmon: (smsc47m1) Only request I/O ports we really use

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The I/O area of the SMSC LPC47M1xx chips which we use, gives access to
a lot of registers, some of which are related to fan speed monitoring
and control, but many are not. At the moment, the smsc47m1 driver
requests the whole I/O port range. This could easily result in
resource conflicts with either ACPI or other drivers.

Request only the I/O ports we really use, to prevent such conflicts.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Sean Fidler <fidlersean@gmail.com>
This commit is contained in:
Jean Delvare 2009-12-16 21:38:26 +01:00
parent 3c57e89b46
commit a0e92d70f3
1 changed files with 89 additions and 10 deletions
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99
drivers/hwmon/smsc47m1.c
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@ -481,13 +481,94 @@ static int __init smsc47m1_find(unsigned short *addr,
return 0;
}
#define CHECK 1
#define REQUEST 2
#define RELEASE 3
/*
* This function can be used to:
* - test for resource conflicts with ACPI
* - request the resources
* - release the resources
* We only allocate the I/O ports we really need, to minimize the risk of
* conflicts with ACPI or with other drivers.
*/
static int smsc47m1_handle_resources(unsigned short address, enum chips type,
int action, struct device *dev)
{
static const u8 ports_m1[] = {
/* register, region length */
0x04, 1,
0x33, 4,
0x56, 7,
};
static const u8 ports_m2[] = {
/* register, region length */
0x04, 1,
0x09, 1,
0x2c, 2,
0x35, 4,
0x56, 7,
0x69, 4,
};
int i, ports_size, err;
const u8 *ports;
switch (type) {
case smsc47m1:
default:
ports = ports_m1;
ports_size = ARRAY_SIZE(ports_m1);
break;
case smsc47m2:
ports = ports_m2;
ports_size = ARRAY_SIZE(ports_m2);
break;
}
for (i = 0; i + 1 < ports_size; i += 2) {
unsigned short start = address + ports[i];
unsigned short len = ports[i + 1];
switch (action) {
case CHECK:
/* Only check for conflicts */
err = acpi_check_region(start, len, DRVNAME);
if (err)
return err;
break;
case REQUEST:
/* Request the resources */
if (!request_region(start, len, DRVNAME)) {
dev_err(dev, "Region 0x%hx-0x%hx already in "
"use!\n", start, start + len);
/* Undo all requests */
for (i -= 2; i >= 0; i -= 2)
release_region(address + ports[i],
ports[i + 1]);
return -EBUSY;
}
break;
case RELEASE:
/* Release the resources */
release_region(start, len);
break;
}
}
return 0;
}
static int __devinit smsc47m1_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct smsc47m1_sio_data *sio_data = dev->platform_data;
struct smsc47m1_data *data;
struct resource *res;
int err = 0;
int err;
int fan1, fan2, fan3, pwm1, pwm2, pwm3;
static const char *names[] = {
@ -496,12 +577,10 @@ static int __devinit smsc47m1_probe(struct platform_device *pdev)
};
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (!request_region(res->start, SMSC_EXTENT, DRVNAME)) {
dev_err(dev, "Region 0x%lx-0x%lx already in use!\n",
(unsigned long)res->start,
(unsigned long)res->end);
return -EBUSY;
}
err = smsc47m1_handle_resources(res->start, sio_data->type,
REQUEST, dev);
if (err < 0)
return err;
if (!(data = kzalloc(sizeof(struct smsc47m1_data), GFP_KERNEL))) {
err = -ENOMEM;
@ -637,7 +716,7 @@ error_free:
platform_set_drvdata(pdev, NULL);
kfree(data);
error_release:
release_region(res->start, SMSC_EXTENT);
smsc47m1_handle_resources(res->start, sio_data->type, RELEASE, dev);
return err;
}
@ -650,7 +729,7 @@ static int __devexit smsc47m1_remove(struct platform_device *pdev)
sysfs_remove_group(&pdev->dev.kobj, &smsc47m1_group);
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
release_region(res->start, SMSC_EXTENT);
smsc47m1_handle_resources(res->start, data->type, RELEASE, &pdev->dev);
platform_set_drvdata(pdev, NULL);
kfree(data);
@ -717,7 +796,7 @@ static int __init smsc47m1_device_add(unsigned short address,
};
int err;
err = acpi_check_resource_conflict(&res);
err = smsc47m1_handle_resources(address, sio_data->type, CHECK, NULL);
if (err)
goto exit;