Commit 03dea86d authored by Tobias Lorenz's avatar Tobias Lorenz Committed by Mauro Carvalho Chehab
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V4L/DVB (7401): radio-si470x: unplugging fixed 



This patch fixes several kernel oops, when unplugging device while it is in
use:

Basically the patch delays freeing of the internal variables in
si470x_usb_driver_disconnect, until the the last user closed the device in
si470x_fops_release. This was implemented a while ago with the help of Oliver
Neukum.

I tested the patch five times (unplugging while in use) without oops coming
from the radio-si470x driver anymore. A remaining oops was coming from the
usbaudio driver, but this is someone else task. Hopefully this fixed all
unplugging issues.

Signed-off-by: default avatarTobias Lorenz <tobias.lorenz@gmx.net>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@infradead.org>
parent b412ba78

drivers/media/radio/radio-si470x.c

+48 −9
Original line number Diff line number Diff line
@@ -85,6 +85,7 @@ 
 *		Oliver Neukum <oliver@neukum.org>

 *		Version 1.0.7

 *		- usb autosuspend support

 *             - unplugging fixed

 *

 * ToDo:

 * - add seeking support
@@ -97,10 +98,10 @@ 
/* driver definitions */

#define DRIVER_AUTHOR "Tobias Lorenz <tobias.lorenz@gmx.net>"

#define DRIVER_NAME "radio-si470x"

#define DRIVER_KERNEL_VERSION KERNEL_VERSION(1, 0, 6)

#define DRIVER_KERNEL_VERSION KERNEL_VERSION(1, 0, 7)

#define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"

#define DRIVER_DESC "USB radio driver for Si470x FM Radio Receivers"

#define DRIVER_VERSION "1.0.6"

#define DRIVER_VERSION "1.0.7"





/* kernel includes */
@@ -424,6 +425,7 @@ struct si470x_device { 


	/* driver management */

	unsigned int users;

       unsigned char disconnected;



	/* Silabs internal registers (0..15) */

	unsigned short registers[RADIO_REGISTER_NUM];
@@ -439,6 +441,12 @@ struct si470x_device { 
};





/*

 * Lock to prevent kfree of data before all users have releases the device.

 */

static DEFINE_MUTEX(open_close_lock);





/*

 * The frequency is set in units of 62.5 Hz when using V4L2_TUNER_CAP_LOW,

 * 62.5 kHz otherwise.
@@ -577,7 +585,7 @@ static int si470x_get_rds_registers(struct si470x_device *radio) 
		usb_rcvintpipe(radio->usbdev, 1),

		(void *) &buf, sizeof(buf), &size, usb_timeout);

	if (size != sizeof(buf))

		printk(KERN_WARNING DRIVER_NAME ": si470x_get_rds_register: "

	       printk(KERN_WARNING DRIVER_NAME ": si470x_get_rds_registers: "

			"return size differs: %d != %zu\n", size, sizeof(buf));

	if (retval < 0)

		printk(KERN_WARNING DRIVER_NAME ": si470x_get_rds_registers: "
@@ -875,6 +883,8 @@ static void si470x_work(struct work_struct *work) 
	struct si470x_device *radio = container_of(work, struct si470x_device,

		work.work);



       if (radio->disconnected)

	       return;

	if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)

		return;
@@ -1001,13 +1011,21 @@ static int si470x_fops_open(struct inode *inode, struct file *file) 
static int si470x_fops_release(struct inode *inode, struct file *file)

{

	struct si470x_device *radio = video_get_drvdata(video_devdata(file));

	int retval;

       int retval = 0;



	if (!radio)

		return -ENODEV;



       mutex_lock(&open_close_lock);

	radio->users--;

	if (radio->users == 0) {

	       if (radio->disconnected) {

		       video_unregister_device(radio->videodev);

		       kfree(radio->buffer);

		       kfree(radio);

		       goto done;

	       }



		/* stop rds reception */

		cancel_delayed_work_sync(&radio->work);
@@ -1016,10 +1034,11 @@ static int si470x_fops_release(struct inode *inode, struct file *file) 


		retval = si470x_stop(radio);

		usb_autopm_put_interface(radio->intf);

		return retval;

	}



	return 0;

done:

       mutex_unlock(&open_close_lock);

       return retval;

}
@@ -1157,6 +1176,9 @@ static int si470x_vidioc_g_ctrl(struct file *file, void *priv, 
{

	struct si470x_device *radio = video_get_drvdata(video_devdata(file));



       if (radio->disconnected)

	       return -EIO;



	switch (ctrl->id) {

	case V4L2_CID_AUDIO_VOLUME:

		ctrl->value = radio->registers[SYSCONFIG2] &
@@ -1181,6 +1203,9 @@ static int si470x_vidioc_s_ctrl(struct file *file, void *priv, 
	struct si470x_device *radio = video_get_drvdata(video_devdata(file));

	int retval;



       if (radio->disconnected)

	       return -EIO;



	switch (ctrl->id) {

	case V4L2_CID_AUDIO_VOLUME:

		radio->registers[SYSCONFIG2] &= ~SYSCONFIG2_VOLUME;
@@ -1243,6 +1268,8 @@ static int si470x_vidioc_g_tuner(struct file *file, void *priv, 
	struct si470x_device *radio = video_get_drvdata(video_devdata(file));

	int retval;



       if (radio->disconnected)

	       return -EIO;

	if (tuner->index > 0)

		return -EINVAL;
@@ -1299,6 +1326,8 @@ static int si470x_vidioc_s_tuner(struct file *file, void *priv, 
	struct si470x_device *radio = video_get_drvdata(video_devdata(file));

	int retval;



       if (radio->disconnected)

	       return -EIO;

	if (tuner->index > 0)

		return -EINVAL;
@@ -1324,6 +1353,9 @@ static int si470x_vidioc_g_frequency(struct file *file, void *priv, 
{

	struct si470x_device *radio = video_get_drvdata(video_devdata(file));



       if (radio->disconnected)

	       return -EIO;



	freq->type = V4L2_TUNER_RADIO;

	freq->frequency = si470x_get_freq(radio);
@@ -1340,6 +1372,8 @@ static int si470x_vidioc_s_frequency(struct file *file, void *priv, 
	struct si470x_device *radio = video_get_drvdata(video_devdata(file));

	int retval;



       if (radio->disconnected)

	       return -EIO;

	if (freq->type != V4L2_TUNER_RADIO)

		return -EINVAL;
@@ -1510,12 +1544,17 @@ static void si470x_usb_driver_disconnect(struct usb_interface *intf) 
{

	struct si470x_device *radio = usb_get_intfdata(intf);



       mutex_lock(&open_close_lock);

       radio->disconnected = 1;

	cancel_delayed_work_sync(&radio->work);

	usb_set_intfdata(intf, NULL);

       if (radio->users == 0) {

	       video_unregister_device(radio->videodev);

	       kfree(radio->buffer);

	       kfree(radio);

       }

       mutex_unlock(&open_close_lock);

}





/*

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