On Wed, Feb 16, 2022 at 11:51:49AM +0200, Mathias Nyman wrote:
> To support systems with several xhci controllers with active
> dbc on each xhci we need to use IDR to identify and give
> an index to each port.
>
> Avoid using global struct tty_driver.driver_state for storing
> dbc port pointer as it won't work with several dbc ports
>
> Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
> ---
> drivers/usb/host/xhci-dbgcap.h | 1 +
> drivers/usb/host/xhci-dbgtty.c | 46 ++++++++++++++++++++++++++++------
> 2 files changed, 40 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/usb/host/xhci-dbgcap.h b/drivers/usb/host/xhci-dbgcap.h
> index 5f3304a06591..ca04192fdab1 100644
> --- a/drivers/usb/host/xhci-dbgcap.h
> +++ b/drivers/usb/host/xhci-dbgcap.h
> @@ -100,6 +100,7 @@ struct dbc_ep {
> struct dbc_port {
> struct tty_port port;
> spinlock_t port_lock; /* port access */
> + int minor;
>
> struct list_head read_pool;
> struct list_head read_queue;
> diff --git a/drivers/usb/host/xhci-dbgtty.c b/drivers/usb/host/xhci-dbgtty.c
> index 059b58f48e3a..d3acc0829ee5 100644
> --- a/drivers/usb/host/xhci-dbgtty.c
> +++ b/drivers/usb/host/xhci-dbgtty.c
> @@ -10,11 +10,14 @@
> #include <linux/slab.h>
> #include <linux/tty.h>
> #include <linux/tty_flip.h>
> +#include <linux/idr.h>
>
> #include "xhci.h"
> #include "xhci-dbgcap.h"
>
> static struct tty_driver *dbc_tty_driver;
> +static struct idr dbc_tty_minors;
> +static DEFINE_MUTEX(dbc_tty_minors_lock);
Why not just use an ida instead? That way you do not need another lock
and it becomes a tiny bit simpler overall.
I'll take this now, but in the future it might be worth to change this.
thanks,
greg k-h
