From 266dcff03eed0050b6af11aaf2a61ab837d7ba3f Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 16 Jul 2014 01:19:34 +0000 Subject: [PATCH] Serial: allow port drivers to have a default attribute group Some serial drivers (like 8250), want to add sysfs files. We need to do so in a race-free way, so allow any port to be able to specify an attribute group that should be added at device creation time. Signed-off-by: Greg Kroah-Hartman Signed-off-by: Yoshihiro YUNOMAE Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/serial_core.c | 24 +++++++++++++++++------- include/linux/serial_core.h | 2 ++ 2 files changed, 19 insertions(+), 7 deletions(-) diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index b70095e55df6..61529a84c3fc 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -2564,12 +2564,6 @@ static const struct attribute_group tty_dev_attr_group = { .attrs = tty_dev_attrs, }; -static const struct attribute_group *tty_dev_attr_groups[] = { - &tty_dev_attr_group, - NULL - }; - - /** * uart_add_one_port - attach a driver-defined port structure * @drv: pointer to the uart low level driver structure for this port @@ -2586,6 +2580,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport) struct tty_port *port; int ret = 0; struct device *tty_dev; + int num_groups; BUG_ON(in_interrupt()); @@ -2619,12 +2614,26 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport) uart_configure_port(drv, state, uport); + num_groups = 2; + if (uport->attr_group) + num_groups++; + + uport->tty_groups = kcalloc(num_groups, sizeof(**uport->tty_groups), + GFP_KERNEL); + if (!uport->tty_groups) { + ret = -ENOMEM; + goto out; + } + uport->tty_groups[0] = &tty_dev_attr_group; + if (uport->attr_group) + uport->tty_groups[1] = uport->attr_group; + /* * Register the port whether it's detected or not. This allows * setserial to be used to alter this port's parameters. */ tty_dev = tty_port_register_device_attr(port, drv->tty_driver, - uport->line, uport->dev, port, tty_dev_attr_groups); + uport->line, uport->dev, port, uport->tty_groups); if (likely(!IS_ERR(tty_dev))) { device_set_wakeup_capable(tty_dev, 1); } else { @@ -2703,6 +2712,7 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport) */ if (uport->type != PORT_UNKNOWN) uport->ops->release_port(uport); + kfree(uport->tty_groups); /* * Indicate that there isn't a port here anymore. diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 5bbb809ee197..cf3a1e789bf5 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -199,6 +199,8 @@ struct uart_port { unsigned char suspended; unsigned char irq_wake; unsigned char unused[2]; + struct attribute_group *attr_group; /* port specific attributes */ + const struct attribute_group **tty_groups; /* all attributes (serial core use only) */ void *private_data; /* generic platform data pointer */ };