[PATCH] Synchronize smd commands

[Eugene Krasnikov]

https://github.com/KrasnikovEugene/wcn36xx/pull/66

2013/7/5 Eugene Krasnikov <k.eugene.e at gmail.com>:
> Add protection to smd api to make sure all smd
> commands are sent sequentially.
>
> Signed-off-by: Eugene Krasnikov <k.eugene.e at gmail.com>
> ---
>  main.c    |  2 ++
>  smd.c     | 24 ++++++++++++++++++++----
>  wcn36xx.h |  6 ++++++
>  3 files changed, 28 insertions(+), 4 deletions(-)
>
> diff --git a/main.c b/main.c
> index 0cc3e02..cb2a5d8 100644
> --- a/main.c
> +++ b/main.c
> @@ -945,6 +945,7 @@ static int __init wcn36xx_init(void)
>         wcn->is_joining = false;
>
>         mutex_init(&wcn->pm_mutex);
> +       mutex_init(&wcn->smd_mutex);
>         wcn->hw->wiphy->n_addresses = ARRAY_SIZE(wcn->addresses);
>         wcn->hw->wiphy->addresses = wcn->addresses;
>
> @@ -1002,6 +1003,7 @@ static void __exit wcn36xx_exit(void)
>         struct wcn36xx *wcn = hw->priv;
>
>         mutex_destroy(&wcn->pm_mutex);
> +       mutex_destroy(&wcn->smd_mutex);
>         ieee80211_unregister_hw(hw);
>         destroy_workqueue(wcn->wq);
>         iounmap(wcn->mmio);
> diff --git a/smd.c b/smd.c
> index ce09563..d291607 100644
> --- a/smd.c
> +++ b/smd.c
> @@ -20,6 +20,7 @@
>  static int wcn36xx_smd_send_and_wait(struct wcn36xx *wcn, size_t len)
>  {
>         int avail;
> +       int ret = 0;
>
>         init_completion(&wcn->smd_compl);
>         avail = smd_write_avail(wcn->smd_ch);
> @@ -29,19 +30,28 @@ static int wcn36xx_smd_send_and_wait(struct wcn36xx *wcn, size_t len)
>                 avail = smd_write(wcn->smd_ch, wcn->smd_buf, len);
>                 if (avail != len) {
>                         wcn36xx_error("Cannot write to SMD channel");
> -                       return -EAGAIN;
> +                       ret = -EAGAIN;
> +                       goto out;
> +
>                 }
>         } else {
>                 wcn36xx_error("SMD channel can accept only %d bytes", avail);
> -               return -ENOMEM;
> +               ret = -ENOMEM;
> +               goto out;
> +
>         }
>
>         if (wait_for_completion_timeout(&wcn->smd_compl,
>                 msecs_to_jiffies(SMD_MSG_TIMEOUT)) <= 0) {
>                 wcn36xx_error("Timeout while waiting SMD response");
> -               return -ETIME;
> +               ret = -ETIME;
> +               goto out;
> +
>         }
> -       return 0;
> +out:
> +       mutex_unlock(&wcn->smd_mutex);
> +       return ret;
> +
>  }
>
>  #define INIT_HAL_MSG(msg_body, type) \
> @@ -54,6 +64,10 @@ static int wcn36xx_smd_send_and_wait(struct wcn36xx *wcn, size_t len)
>
>  #define PREPARE_HAL_BUF(send_buf, msg_body) \
>         do {                                                    \
> +               struct wcn36xx *__wcn =                         \
> +                       container_of(&send_buf,                 \
> +                                    struct wcn36xx, smd_buf);  \
> +               mutex_lock(&__wcn->smd_mutex);                  \
>                 memset(send_buf, 0, msg_body.header.len);       \
>                 memcpy(send_buf, &msg_body, sizeof(msg_body));  \
>         } while (0)                                             \
> @@ -101,6 +115,8 @@ int wcn36xx_smd_load_nv(struct wcn36xx *wcn)
>                         msg_body.header.len = sizeof(msg_body) + fw_bytes_left;
>
>                 }
> +               /* smd_buf must be protected with  mutex */
> +               mutex_lock(&wcn->smd_mutex);
>
>                 /* Add load NV request message header */
>                 memcpy(wcn->smd_buf, &msg_body, sizeof(msg_body));
> diff --git a/wcn36xx.h b/wcn36xx.h
> index 2c72349..653381f 100644
> --- a/wcn36xx.h
> +++ b/wcn36xx.h
> @@ -139,7 +139,13 @@ struct wcn36xx {
>
>         /* SMD related */
>         smd_channel_t           *smd_ch;
> +       /*
> +        * smd_buf must be protected with smd_mutex to garantee
> +        * that all messages are sent one after another
> +        */
>         u8                      *smd_buf;
> +       struct mutex            smd_mutex;
> +
>         struct work_struct      smd_work;
>         struct work_struct      start_work;
>         struct work_struct      rx_ready_work;
> --
> 1.7.11.3
>



-- 
Best regards,
Eugene