Convert this driver to use the new i2c_new_dummy_device() call and bail
out if the dummy device cannot be registered to make failure more
visible to the user.
Signed-off-by: Wolfram Sang <[email protected]>
---
Change since v1:
* reworded commit message because there was no NULL ptr access
drivers/media/i2c/ir-kbd-i2c.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)
diff --git a/drivers/media/i2c/ir-kbd-i2c.c b/drivers/media/i2c/ir-kbd-i2c.c
index 876d7587a1da..f46717052efc 100644
--- a/drivers/media/i2c/ir-kbd-i2c.c
+++ b/drivers/media/i2c/ir-kbd-i2c.c
@@ -885,9 +885,12 @@ static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
INIT_DELAYED_WORK(&ir->work, ir_work);
if (probe_tx) {
- ir->tx_c = i2c_new_dummy(client->adapter, 0x70);
- if (!ir->tx_c) {
+ ir->tx_c = devm_i2c_new_dummy_device(&client->dev,
+ client->adapter, 0x70);
+ if (IS_ERR(ir->tx_c)) {
dev_err(&client->dev, "failed to setup tx i2c address");
+ err = PTR_ERR(ir->tx_c);
+ goto err_out_free;
} else if (!zilog_init(ir)) {
ir->carrier = 38000;
ir->duty_cycle = 40;
@@ -904,9 +907,6 @@ static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
return 0;
err_out_free:
- if (ir->tx_c)
- i2c_unregister_device(ir->tx_c);
-
/* Only frees rc if it were allocated internally */
rc_free_device(rc);
return err;
@@ -919,9 +919,6 @@ static int ir_remove(struct i2c_client *client)
/* kill outstanding polls */
cancel_delayed_work_sync(&ir->work);
- if (ir->tx_c)
- i2c_unregister_device(ir->tx_c);
-
/* unregister device */
rc_unregister_device(ir->rc);
--
2.20.1
Em Tue, 30 Jul 2019 19:55:54 +0200
Wolfram Sang <[email protected]> escreveu:
> Convert this driver to use the new i2c_new_dummy_device() call and bail
> out if the dummy device cannot be registered to make failure more
> visible to the user.
>
Please don't do that.
At first glance, devm_* sounds a good idea, but we had enough issues
using it on media system.
I don't mind mind much if some SoC specific would use it, but doing
it on generic drivers is a very bad idea. We have removed almost all
devm_* calls from the media system.
The problem with devm is that it the de-allocation routines aren't
called during device unbind. They happen a way later, only when the
device itself is physically removed, or the driver is removed.
That caused lots of headaches to debug memory lifetime issues on
media.
> Signed-off-by: Wolfram Sang <[email protected]>
> ---
>
> Change since v1:
>
> * reworded commit message because there was no NULL ptr access
>
> drivers/media/i2c/ir-kbd-i2c.c | 13 +++++--------
> 1 file changed, 5 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/media/i2c/ir-kbd-i2c.c b/drivers/media/i2c/ir-kbd-i2c.c
> index 876d7587a1da..f46717052efc 100644
> --- a/drivers/media/i2c/ir-kbd-i2c.c
> +++ b/drivers/media/i2c/ir-kbd-i2c.c
> @@ -885,9 +885,12 @@ static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
> INIT_DELAYED_WORK(&ir->work, ir_work);
>
> if (probe_tx) {
> - ir->tx_c = i2c_new_dummy(client->adapter, 0x70);
> - if (!ir->tx_c) {
> + ir->tx_c = devm_i2c_new_dummy_device(&client->dev,
> + client->adapter, 0x70);
> + if (IS_ERR(ir->tx_c)) {
> dev_err(&client->dev, "failed to setup tx i2c address");
> + err = PTR_ERR(ir->tx_c);
> + goto err_out_free;
> } else if (!zilog_init(ir)) {
> ir->carrier = 38000;
> ir->duty_cycle = 40;
> @@ -904,9 +907,6 @@ static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
> return 0;
>
> err_out_free:
> - if (ir->tx_c)
> - i2c_unregister_device(ir->tx_c);
> -
> /* Only frees rc if it were allocated internally */
> rc_free_device(rc);
> return err;
> @@ -919,9 +919,6 @@ static int ir_remove(struct i2c_client *client)
> /* kill outstanding polls */
> cancel_delayed_work_sync(&ir->work);
>
> - if (ir->tx_c)
> - i2c_unregister_device(ir->tx_c);
> -
> /* unregister device */
> rc_unregister_device(ir->rc);
>
Thanks,
Mauro
On Sat, Aug 03, 2019 at 01:17:49PM -0300, Mauro Carvalho Chehab wrote:
> Em Tue, 30 Jul 2019 19:55:54 +0200
> Wolfram Sang <[email protected]> escreveu:
>
> > Convert this driver to use the new i2c_new_dummy_device() call and bail
> > out if the dummy device cannot be registered to make failure more
> > visible to the user.
> >
>
> Please don't do that.
>
> At first glance, devm_* sounds a good idea, but we had enough issues
> using it on media system.
>
> I don't mind mind much if some SoC specific would use it, but doing
> it on generic drivers is a very bad idea. We have removed almost all
> devm_* calls from the media system.
>
> The problem with devm is that it the de-allocation routines aren't
> called during device unbind. They happen a way later, only when the
> device itself is physically removed, or the driver is removed.
Yes, good point.
> That caused lots of headaches to debug memory lifetime issues on
> media.
Indeed this becomes much more complex. Explicit freeing is much better.
Thanks,
Sean