Hi Andrzej,
On Mon, Aug 27, 2018 at 06:15:59PM +0200, Andrzej Hajda wrote:
> On 30.07.2018 18:42, Russell King wrote:
> > static void tda998x_destroy(struct tda998x_priv *priv)
> > {
> > + drm_bridge_remove(&priv->bridge);
> > +
> > /* disable all IRQs and free the IRQ handler */
> > cec_write(priv, REG_CEC_RXSHPDINTENA, 0);
> > reg_clear(priv, REG_INT_FLAGS_2, INT_FLAGS_2_EDID_BLK_RD);
> > @@ -1650,6 +1663,7 @@ static int tda998x_create(struct i2c_client *client, struct tda998x_priv *priv)
> > mutex_init(&priv->mutex); /* protect the page access */
> > mutex_init(&priv->audio_mutex); /* protect access from audio thread */
> > mutex_init(&priv->edid_mutex);
> > + INIT_LIST_HEAD(&priv->bridge.list);
>
> This line can be probably removed, unless there is a reason I am not
> aware of.
The addition above of drm_bridge_remove() to tda998x_destroy() means
that we end up calling this function in the error cleanup path. This
avoids unnecessary complexity with lots of different gotos - tda998x
has had a long history of not cleaning up stuff properly.
devm interfaces for bridge do not help avoid that - devm stuff only
works if everything that is registered previously is cleaned up via
devm mechanisms to ensure that a device's interface becomes unavailable
before stuff (eg, edid timers, detect work) is started to be cleaned up.
Otherwise, there's a chance of this stuff being triggered during
tear-down.
> > +static int tda998x_bind(struct device *dev, struct device *master, void *data)
> > +{
> > + struct i2c_client *client = to_i2c_client(dev);
> > + struct drm_device *drm = data;
> > + struct tda998x_priv *priv;
> > + int ret;
> > +
> > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> > + if (!priv)
> > + return -ENOMEM;
> > +
> > + dev_set_drvdata(dev, priv);
> > +
> > + ret = tda998x_create(client, priv);
> > + if (ret)
> > + return ret;
> > +
> > + ret = tda998x_encoder_init(dev, drm);
> > + if (ret) {
> > + tda998x_destroy(priv);
> > + return ret;
> > + }
> > + return 0;
>
> It could be replaced by:
> ret = tda998x_encoder_init(dev, drm);
> if (ret)
> tda998x_destroy(priv);
> return ret;
>
> but this is probably matter of taste.
It's not clear to me what "It" is - I think you're suggesting combining
tda998x_create() and tda998x_encoder_init() ?
The code is structured this way to make the following patches easier -
there is no point of combining things only to have to then break them
apart again in a later patch. Please see patch 7, where tda998x_create()
moves out of this function, where exactly this happens.
> Moreover I guess priv->is_on could be removed if enable/disable
> callbacks are called only by drm_core, but this is for another patch.
Is it guaranteed that a bridge ->enable or ->disable callback won't be
called twice, even for legacy drivers? I think atomic guarantees this
but I don't think it's guaranteed for legacy drivers.
I'm guessing Rob had a reason why he added the check when he originally
created the driver (encoder ->dpms can be called for the same dpms
state multiple times?)
--
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 13.8Mbps down 630kbps up
According to speedtest.net: 13Mbps down 490kbps up
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
