The I/O area of the SMSC LPC47M1xx/292 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@xxxxxxxxxxxx>
---
This needs testing! If anyone around has a device supported by the
smsc47m1 driver and has the possibility to test this patch, please do
and report.
drivers/hwmon/smsc47m1.c | 89 ++++++++++++++++++++++++++++++++++++++++------
1 file changed, 79 insertions(+), 10 deletions(-)
--- linux-2.6.32-rc6.orig/drivers/hwmon/smsc47m1.c 2009-11-11 15:29:11.000000000 +0100
+++ linux-2.6.32-rc6/drivers/hwmon/smsc47m1.c 2009-11-11 22:15:21.000000000 +0100
@@ -481,13 +481,85 @@ static int __init smsc47m1_find(unsigned
return 0;
}
+/*
+ * This function can be used to:
+ * - test for resource conflicts with ACPI (dev == NULL, request == 0)
+ * - request the resources (dev != NULL, request == 1)
+ * - release the resources (dev != NULL, request == 0)
+ * 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,
+ struct device *dev, int request)
+{
+ 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];
+
+ if (!dev) {
+ /* Only check for conflicts */
+ err = acpi_check_region(start, len, DRVNAME);
+ if (err)
+ return err;
+ } else if (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(start, len);
+ return -EBUSY;
+ }
+ } else {
+ /* Release the resources */
+ release_region(start, len);
+ }
+ }
+
+ 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 +568,9 @@ static int __devinit smsc47m1_probe(stru
};
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, dev, 1);
+ if (err < 0)
+ return err;
if (!(data = kzalloc(sizeof(struct smsc47m1_data), GFP_KERNEL))) {
err = -ENOMEM;
@@ -637,7 +706,7 @@ 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, dev, 0);
return err;
}
@@ -650,7 +719,7 @@ static int __devexit smsc47m1_remove(str
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, &pdev->dev, 0);
platform_set_drvdata(pdev, NULL);
kfree(data);
@@ -717,7 +786,7 @@ static int __init smsc47m1_device_add(un
};
int err;
- err = acpi_check_resource_conflict(&res);
+ err = smsc47m1_handle_resources(address, sio_data->type, NULL, 0);
if (err)
goto exit;
--
Jean Delvare
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