Re: [PATCH v3 12/14] intel_gna: add a 'misc' device
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-05-13 11:18:33
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On Thu, May 13, 2021 at 01:00:38PM +0200, Maciej Kwapulinski wrote:
quoted hunk ↗ jump to hunk
The new 'misc' device is the node for applications in user space to interact with the driver. Signed-off-by: Maciej Kwapulinski <redacted> Tested-by: Savo Novakovic <redacted> --- drivers/misc/intel/gna/device.c | 52 +++++++++++++++++++++++++++++++-- drivers/misc/intel/gna/device.h | 11 +++---- 2 files changed, 55 insertions(+), 8 deletions(-)diff --git a/drivers/misc/intel/gna/device.c b/drivers/misc/intel/gna/device.c index 0e31b8c6bb70..1e6345a8325b 100644 --- a/drivers/misc/intel/gna/device.c +++ b/drivers/misc/intel/gna/device.c@@ -20,6 +20,18 @@ module_param(recovery_timeout, int, 0644); MODULE_PARM_DESC(recovery_timeout, "Recovery timeout in seconds"); #endif +struct file; + +static int gna_open(struct inode *inode, struct file *f) +{ + return -EPERM; +}
That sucks, why have an open that does nothing but fail?
quoted hunk ↗ jump to hunk
+ +static const struct file_operations gna_file_ops = { + .owner = THIS_MODULE, + .open = gna_open, +}; + static void gna_devm_idr_destroy(void *data) { struct idr *idr = data;@@ -27,6 +39,36 @@ static void gna_devm_idr_destroy(void *data) idr_destroy(idr); } +static void gna_devm_deregister_misc_dev(void *data)
Why is this a void *? This isn't windows, use real pointer types everywhere in the kernel please.
+{
+ struct miscdevice *misc = data;
+
+ misc_deregister(misc);
+}
+
+static int gna_devm_register_misc_dev(struct device *parent, struct miscdevice *misc)
+{
+ int ret;
+
+ ret = misc_register(misc);
+ if (ret) {
+ dev_err(parent, "misc device %s registering failed. errcode: %d\n",
+ misc->name, ret);
+ gna_devm_deregister_misc_dev(misc);
+ } else {
+ dev_dbg(parent, "device: %s registered\n",
+ misc->name);You have loads of debugging in this driver still, is it really needed?
+ } + + ret = devm_add_action(parent, gna_devm_deregister_misc_dev, misc);
Why do you need this? thanks, greg k-h