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authorSudip Mukherjee <sudipm.mukherjee@gmail.com>2016-11-12 21:22:12 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-11-29 20:25:34 +0100
commitdd5c472a60e43549d789a17a8444513eec64bd7e (patch)
tree0c4e511c74fdded742c37f07246d460fc6828446 /drivers/char/ppdev.c
parent826a4c6574efafdcfc292cdaf4dd2ccd6133d5f0 (diff)
downloadleg-kernel-dd5c472a60e43549d789a17a8444513eec64bd7e.tar.gz
ppdev: check before attaching port
After parport starts using the device model, all pardevice drivers should decide in their match_port callback function if they want to attach with that particulatr port. ppdev has been converted to use the new parport device-model code but pp_attach() tried to attach with all the ports. Create a new array of pointer and use that to remember the ports we have attached. And use that information to skip attaching ports which we have already attached. Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/char/ppdev.c')
-rw-r--r--drivers/char/ppdev.c23
1 files changed, 21 insertions, 2 deletions
diff --git a/drivers/char/ppdev.c b/drivers/char/ppdev.c
index 85c63e49df7f..02819e0703c8 100644
--- a/drivers/char/ppdev.c
+++ b/drivers/char/ppdev.c
@@ -86,6 +86,9 @@ struct pp_struct {
long default_inactivity;
};
+/* should we use PARDEVICE_MAX here? */
+static struct device *devices[PARPORT_MAX];
+
/* pp_struct.flags bitfields */
#define PP_CLAIMED (1<<0)
#define PP_EXCL (1<<1)
@@ -789,13 +792,29 @@ static const struct file_operations pp_fops = {
static void pp_attach(struct parport *port)
{
- device_create(ppdev_class, port->dev, MKDEV(PP_MAJOR, port->number),
- NULL, "parport%d", port->number);
+ struct device *ret;
+
+ if (devices[port->number])
+ return;
+
+ ret = device_create(ppdev_class, port->dev,
+ MKDEV(PP_MAJOR, port->number), NULL,
+ "parport%d", port->number);
+ if (IS_ERR(ret)) {
+ pr_err("Failed to create device parport%d\n",
+ port->number);
+ return;
+ }
+ devices[port->number] = ret;
}
static void pp_detach(struct parport *port)
{
+ if (!devices[port->number])
+ return;
+
device_destroy(ppdev_class, MKDEV(PP_MAJOR, port->number));
+ devices[port->number] = NULL;
}
static int pp_probe(struct pardevice *par_dev)