| Message ID | 1467360098-12539-3-git-send-email-andi.shyti@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jul 01, 2016 at 05:01:25PM +0900, Andi Shyti wrote: > Some drivers don't necessarily need to have a FIFO managed buffer > for their transfers. Drivers now should call > lirc_register_bufferless_driver in order to handle the buffer > themselves. > > The function works exaclty like lirc_register_driver except of > the buffer allocation. Indeed transmit-only devices don't need an input buffer, which is just a waste of memory. However can't lirc_register_driver() figure out from the features if the driver is capable of receiving, i.e. int lirc_register_driver(struct lirc_driver *d) { int err, minor; minor = lirc_allocate_driver(d); if (minor < 0) return minor; if (d->features & LIRC_CAN_REC_MODE2) { err = lirc_allocate_buffer(irctls[minor]); if (err) lirc_unregister_driver(minor); } return err ? err : minor; } Sean > > Signed-off-by: Andi Shyti <andi.shyti@samsung.com> > --- > drivers/media/rc/lirc_dev.c | 44 ++++++++++++++++++++++++++++++++++---------- > include/media/lirc_dev.h | 12 ++++++++++++ > 2 files changed, 46 insertions(+), 10 deletions(-) > > diff --git a/drivers/media/rc/lirc_dev.c b/drivers/media/rc/lirc_dev.c > index 5716978..fa562a3 100644 > --- a/drivers/media/rc/lirc_dev.c > +++ b/drivers/media/rc/lirc_dev.c > @@ -205,12 +205,14 @@ err_out: > > static int lirc_allocate_buffer(struct irctl *ir) > { > - int err; > + int err = 0; > int bytes_in_key; > unsigned int chunk_size; > unsigned int buffer_size; > struct lirc_driver *d = &ir->d; > > + mutex_lock(&lirc_dev_lock); > + > bytes_in_key = BITS_TO_LONGS(d->code_length) + > (d->code_length % 8 ? 1 : 0); > buffer_size = d->buffer_size ? d->buffer_size : BUFLEN / bytes_in_key; > @@ -220,21 +222,26 @@ static int lirc_allocate_buffer(struct irctl *ir) > ir->buf = d->rbuf; > } else { > ir->buf = kmalloc(sizeof(struct lirc_buffer), GFP_KERNEL); > - if (!ir->buf) > - return -ENOMEM; > + if (!ir->buf) { > + err = -ENOMEM; > + goto out; > + } > > err = lirc_buffer_init(ir->buf, chunk_size, buffer_size); > if (err) { > kfree(ir->buf); > - return err; > + goto out; > } > } > ir->chunk_size = ir->buf->chunk_size; > > - return 0; > +out: > + mutex_unlock(&lirc_dev_lock); > + > + return err; > } > > -int lirc_register_driver(struct lirc_driver *d) > +static int lirc_allocate_driver(struct lirc_driver *d) > { > struct irctl *ir; > int minor; > @@ -342,10 +349,6 @@ int lirc_register_driver(struct lirc_driver *d) > /* some safety check 8-) */ > d->name[sizeof(d->name)-1] = '\0'; > > - err = lirc_allocate_buffer(ir); > - if (err) > - goto out_lock; > - > if (d->features == 0) > d->features = LIRC_CAN_REC_LIRCCODE; > > @@ -385,8 +388,29 @@ out_lock: > out: > return err; > } > + > +int lirc_register_driver(struct lirc_driver *d) > +{ > + int err, minor; > + > + minor = lirc_allocate_driver(d); > + if (minor < 0) > + return minor; > + > + err = lirc_allocate_buffer(irctls[minor]); > + if (err) > + lirc_unregister_driver(minor); > + > + return err ? err : minor; > +} > EXPORT_SYMBOL(lirc_register_driver); > > +int lirc_register_bufferless_driver(struct lirc_driver *d) > +{ > + return lirc_allocate_driver(d); > +} > +EXPORT_SYMBOL(lirc_register_bufferless_driver); > + > int lirc_unregister_driver(int minor) > { > struct irctl *ir; > diff --git a/include/media/lirc_dev.h b/include/media/lirc_dev.h > index 0ab59a5..8bed57a 100644 > --- a/include/media/lirc_dev.h > +++ b/include/media/lirc_dev.h > @@ -214,6 +214,18 @@ struct lirc_driver { > */ > extern int lirc_register_driver(struct lirc_driver *d); > > +/* int lirc_register_bufferless_driver - allocates a lirc bufferless driver > + * @d: reference to the lirc_driver to initialize > + * > + * The difference between lirc_register_driver and > + * lirc_register_bufferless_driver is that the latter doesn't allocate any > + * buffer, which means that the driver using the lirc_driver should take care of > + * it by itself. > + * > + * returns 0 on success or a the negative errno number in case of failure. > + */ > +extern int lirc_register_bufferless_driver(struct lirc_driver *d); > + > /* returns negative value on error or 0 if success > */ > extern int lirc_unregister_driver(int minor); > -- > 2.8.1 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/media/rc/lirc_dev.c b/drivers/media/rc/lirc_dev.c index 5716978..fa562a3 100644 --- a/drivers/media/rc/lirc_dev.c +++ b/drivers/media/rc/lirc_dev.c @@ -205,12 +205,14 @@ err_out: static int lirc_allocate_buffer(struct irctl *ir) { - int err; + int err = 0; int bytes_in_key; unsigned int chunk_size; unsigned int buffer_size; struct lirc_driver *d = &ir->d; + mutex_lock(&lirc_dev_lock); + bytes_in_key = BITS_TO_LONGS(d->code_length) + (d->code_length % 8 ? 1 : 0); buffer_size = d->buffer_size ? d->buffer_size : BUFLEN / bytes_in_key; @@ -220,21 +222,26 @@ static int lirc_allocate_buffer(struct irctl *ir) ir->buf = d->rbuf; } else { ir->buf = kmalloc(sizeof(struct lirc_buffer), GFP_KERNEL); - if (!ir->buf) - return -ENOMEM; + if (!ir->buf) { + err = -ENOMEM; + goto out; + } err = lirc_buffer_init(ir->buf, chunk_size, buffer_size); if (err) { kfree(ir->buf); - return err; + goto out; } } ir->chunk_size = ir->buf->chunk_size; - return 0; +out: + mutex_unlock(&lirc_dev_lock); + + return err; } -int lirc_register_driver(struct lirc_driver *d) +static int lirc_allocate_driver(struct lirc_driver *d) { struct irctl *ir; int minor; @@ -342,10 +349,6 @@ int lirc_register_driver(struct lirc_driver *d) /* some safety check 8-) */ d->name[sizeof(d->name)-1] = '\0'; - err = lirc_allocate_buffer(ir); - if (err) - goto out_lock; - if (d->features == 0) d->features = LIRC_CAN_REC_LIRCCODE; @@ -385,8 +388,29 @@ out_lock: out: return err; } + +int lirc_register_driver(struct lirc_driver *d) +{ + int err, minor; + + minor = lirc_allocate_driver(d); + if (minor < 0) + return minor; + + err = lirc_allocate_buffer(irctls[minor]); + if (err) + lirc_unregister_driver(minor); + + return err ? err : minor; +} EXPORT_SYMBOL(lirc_register_driver); +int lirc_register_bufferless_driver(struct lirc_driver *d) +{ + return lirc_allocate_driver(d); +} +EXPORT_SYMBOL(lirc_register_bufferless_driver); + int lirc_unregister_driver(int minor) { struct irctl *ir; diff --git a/include/media/lirc_dev.h b/include/media/lirc_dev.h index 0ab59a5..8bed57a 100644 --- a/include/media/lirc_dev.h +++ b/include/media/lirc_dev.h @@ -214,6 +214,18 @@ struct lirc_driver { */ extern int lirc_register_driver(struct lirc_driver *d); +/* int lirc_register_bufferless_driver - allocates a lirc bufferless driver + * @d: reference to the lirc_driver to initialize + * + * The difference between lirc_register_driver and + * lirc_register_bufferless_driver is that the latter doesn't allocate any + * buffer, which means that the driver using the lirc_driver should take care of + * it by itself. + * + * returns 0 on success or a the negative errno number in case of failure. + */ +extern int lirc_register_bufferless_driver(struct lirc_driver *d); + /* returns negative value on error or 0 if success */ extern int lirc_unregister_driver(int minor);
Some drivers don't necessarily need to have a FIFO managed buffer for their transfers. Drivers now should call lirc_register_bufferless_driver in order to handle the buffer themselves. The function works exaclty like lirc_register_driver except of the buffer allocation. Signed-off-by: Andi Shyti <andi.shyti@samsung.com> --- drivers/media/rc/lirc_dev.c | 44 ++++++++++++++++++++++++++++++++++---------- include/media/lirc_dev.h | 12 ++++++++++++ 2 files changed, 46 insertions(+), 10 deletions(-)