[PATCH 1/2] PNP: Add a release method to system resource driver

From: Matthew Garrett
Date: Tue Sep 25 2012 - 09:26:12 EST


This could conceivably be hotpluggable, and we may want to displace it
from devices under certain circustances, so add a release method to hand
back the resources.

Signed-off-by: Matthew Garrett <mjg@xxxxxxxxxx>
---
drivers/pnp/system.c | 30 ++++++++++++++++++++++++++----
1 file changed, 26 insertions(+), 4 deletions(-)

diff --git a/drivers/pnp/system.c b/drivers/pnp/system.c
index 49c1720..b0a50f2 100644
--- a/drivers/pnp/system.c
+++ b/drivers/pnp/system.c
@@ -52,7 +52,17 @@ static void reserve_range(struct pnp_dev *dev, struct resource *r, int port)
res ? "has been" : "could not be");
}

-static void reserve_resources_of_dev(struct pnp_dev *dev)
+static void free_range(struct pnp_dev *dev, struct resource *r, int port)
+{
+ resource_size_t start = r->start, end = r->end;
+
+ if (port)
+ release_region(start, end - start + 1);
+ else
+ release_mem_region(start, end - start + 1);
+}
+
+static void handle_resources_of_dev(struct pnp_dev *dev, bool free)
{
struct resource *res;
int i;
@@ -75,29 +85,41 @@ static void reserve_resources_of_dev(struct pnp_dev *dev)
if (res->end < res->start)
continue; /* invalid */

- reserve_range(dev, res, 1);
+ if (free)
+ free_range(dev, res, 1);
+ else
+ reserve_range(dev, res, 1);
}

for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_MEM, i)); i++) {
if (res->flags & IORESOURCE_DISABLED)
continue;

- reserve_range(dev, res, 0);
+ if (free)
+ free_range(dev, res, 0);
+ else
+ reserve_range(dev, res, 0);
}
}

static int system_pnp_probe(struct pnp_dev *dev,
const struct pnp_device_id *dev_id)
{
- reserve_resources_of_dev(dev);
+ handle_resources_of_dev(dev, false);
return 0;
}

+static void system_pnp_remove(struct pnp_dev *dev)
+{
+ handle_resources_of_dev(dev, true);
+}
+
static struct pnp_driver system_pnp_driver = {
.name = "system",
.id_table = pnp_dev_table,
.flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
.probe = system_pnp_probe,
+ .remove = system_pnp_remove,
};

static int __init pnp_system_init(void)
--
1.7.11.4

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