Re: [PATCH v2 15/20] tty: n_gsm: fix missing update of modem controls after DLCI open

[Greg KH <gregkh@linuxfoundation.org>]

On Tue, Apr 19, 2022 at 01:07:24AM -0700, D. Starke wrote:
> From: Daniel Starke <daniel.starke@siemens.com>
> 
> Currently the peer is not informed about the initial state of the modem
> control lines after a new DLCI has been opened.
> Fix this by sending the initial modem control line states after DLCI open.
> 
> Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
> Cc: stable@vger.kernel.org
> Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
> ---
>  drivers/tty/n_gsm.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
> index f3fb66be8513..07d03447cdfd 100644
> --- a/drivers/tty/n_gsm.c
> +++ b/drivers/tty/n_gsm.c
> @@ -370,6 +370,7 @@ static const u8 gsm_fcs8[256] = {
>  #define GOOD_FCS	0xCF
>  
>  static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len);
> +static int gsmtty_modem_update(struct gsm_dlci *dlci, u8 brk);
>  
>  /**
>   *	gsm_fcs_add	-	update FCS
> @@ -1479,6 +1480,9 @@ static void gsm_dlci_open(struct gsm_dlci *dlci)
>  		pr_debug("DLCI %d goes open.\n", dlci->addr);
>  	/* Register gsmtty driver,report gsmtty dev add uevent for user */
>  	tty_register_device(gsm_tty_driver, dlci->addr, NULL);
> +	/* Send current modem state */
> +	if (dlci->addr)
> +		gsmtty_modem_update(dlci, 0);
>  	wake_up(&dlci->gsm->event);
>  }
>  
> -- 
> 2.25.1
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
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thanks,

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