| Message ID | 20180430090324.30845-1-david.engraf@sysgo.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi David, On Mon, Apr 30, 2018 at 11:03:24AM +0200, David Engraf wrote: > The current version only supports forwarding a single byte to the tty > layer. > > This patch adds serio_write_length() to allow a serport driver writing > multiple bytes at once. The patch also includes a fallback to > serio_write_length() when a driver did not register a single byte function. Without users I do not see point for this API. Thanks.
Hi Dmitry, On 30.04.2018 at 23:20, Dmitry Torokhov wrote: > Hi David, > > On Mon, Apr 30, 2018 at 11:03:24AM +0200, David Engraf wrote: >> The current version only supports forwarding a single byte to the tty >> layer. >> >> This patch adds serio_write_length() to allow a serport driver writing >> multiple bytes at once. The patch also includes a fallback to >> serio_write_length() when a driver did not register a single byte function. > > Without users I do not see point for this API. Here is an incomplete list of drivers calling serio_write() in a loop: - drivers/media/usb/rainshadow-cec/rainshadow-cec.c - drivers/input/serio/serio_raw.c - drivers/input/touchscreen/elo.c I can simplify these drivers by using serio_write_length() if you want to have some users for the new API. Best regards - David -- To unsubscribe from this list: send the line "unsubscribe linux-input" 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/input/serio/serport.c b/drivers/input/serio/serport.c index f8ead9f9c77e..209343f636a3 100644 --- a/drivers/input/serio/serport.c +++ b/drivers/input/serio/serport.c @@ -45,10 +45,11 @@ struct serport { * Callback functions from the serio code. */ -static int serport_serio_write(struct serio *serio, unsigned char data) +static int serport_serio_write_length(struct serio *serio, + const unsigned char *data, int count) { struct serport *serport = serio->port_data; - return -(serport->tty->ops->write(serport->tty, &data, 1) != 1); + return -(serport->tty->ops->write(serport->tty, data, count) != count); } static int serport_serio_open(struct serio *serio) @@ -176,7 +177,7 @@ static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, u snprintf(serio->phys, sizeof(serio->phys), "%s/serio0", tty_name(tty)); serio->id = serport->id; serio->id.type = SERIO_RS232; - serio->write = serport_serio_write; + serio->write_length = serport_serio_write_length; serio->open = serport_serio_open; serio->close = serport_serio_close; serio->port_data = serport; diff --git a/include/linux/serio.h b/include/linux/serio.h index 138a5efe863a..6f5cb92d0f22 100644 --- a/include/linux/serio.h +++ b/include/linux/serio.h @@ -35,6 +35,8 @@ struct serio { spinlock_t lock; int (*write)(struct serio *, unsigned char); + int (*write_length)(struct serio *serio, const unsigned char *data, + int count); int (*open)(struct serio *); void (*close)(struct serio *); int (*start)(struct serio *); @@ -122,12 +124,21 @@ void serio_unregister_driver(struct serio_driver *drv); module_driver(__serio_driver, serio_register_driver, \ serio_unregister_driver) +static inline int serio_write_length(struct serio *serio, + const unsigned char *data, int count) +{ + if (serio->write_length) + return serio->write_length(serio, data, count); + else + return -1; +} + static inline int serio_write(struct serio *serio, unsigned char data) { if (serio->write) return serio->write(serio, data); else - return -1; + return serio_write_length(serio, &data, 1); } static inline void serio_drv_write_wakeup(struct serio *serio)
The current version only supports forwarding a single byte to the tty layer. This patch adds serio_write_length() to allow a serport driver writing multiple bytes at once. The patch also includes a fallback to serio_write_length() when a driver did not register a single byte function. Signed-off-by: David Engraf <david.engraf@sysgo.com> --- drivers/input/serio/serport.c | 7 ++++--- include/linux/serio.h | 13 ++++++++++++- 2 files changed, 16 insertions(+), 4 deletions(-)