[PATCH linux dev-5.1] OCC: FSI and hwmon: Add sequence numbering

[Lei YU]

Reviewed-by: Lei YU <mine260309 at gmail.com>

On Thu, Jun 27, 2019 at 3:06 AM Eddie James <eajames at linux.ibm.com> wrote:
>
> Sequence numbering of the commands submitted to the OCC is required by
> the OCC interface specification. Add sequence numbering and check for
> the correct sequence number on the response.
>
> Signed-off-by: Eddie James <eajames at linux.ibm.com>
> ---
>  drivers/fsi/fsi-occ.c      | 15 ++++++++++++---
>  drivers/hwmon/occ/common.c |  4 ++--
>  drivers/hwmon/occ/common.h |  1 +
>  3 files changed, 15 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/fsi/fsi-occ.c b/drivers/fsi/fsi-occ.c
> index a2301ce..7da9c81 100644
> --- a/drivers/fsi/fsi-occ.c
> +++ b/drivers/fsi/fsi-occ.c
> @@ -412,6 +412,7 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
>                 msecs_to_jiffies(OCC_CMD_IN_PRG_WAIT_MS);
>         struct occ *occ = dev_get_drvdata(dev);
>         struct occ_response *resp = response;
> +       u8 seq_no;
>         u16 resp_data_length;
>         unsigned long start;
>         int rc;
> @@ -426,6 +427,8 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
>
>         mutex_lock(&occ->occ_lock);
>
> +       /* Extract the seq_no from the command (first byte) */
> +       seq_no = *(const u8 *)request;
>         rc = occ_putsram(occ, OCC_SRAM_CMD_ADDR, request, req_len);
>         if (rc)
>                 goto done;
> @@ -441,11 +444,17 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
>                 if (rc)
>                         goto done;
>
> -               if (resp->return_status == OCC_RESP_CMD_IN_PRG) {
> +               if (resp->return_status == OCC_RESP_CMD_IN_PRG ||
> +                   resp->seq_no != seq_no) {
>                         rc = -ETIMEDOUT;
>
> -                       if (time_after(jiffies, start + timeout))
> -                               break;
> +                       if (time_after(jiffies, start + timeout)) {
> +                               dev_err(occ->dev, "resp timeout status=%02x "
> +                                       "resp seq_no=%d our seq_no=%d\n",
> +                                       resp->return_status, resp->seq_no,
> +                                       seq_no);
> +                               goto done;
> +                       }
>
>                         set_current_state(TASK_UNINTERRUPTIBLE);
>                         schedule_timeout(wait_time);
> diff --git a/drivers/hwmon/occ/common.c b/drivers/hwmon/occ/common.c
> index d7cc0d2..e9d7167 100644
> --- a/drivers/hwmon/occ/common.c
> +++ b/drivers/hwmon/occ/common.c
> @@ -122,12 +122,12 @@ struct extended_sensor {
>  static int occ_poll(struct occ *occ)
>  {
>         int rc;
> -       u16 checksum = occ->poll_cmd_data + 1;
> +       u16 checksum = occ->poll_cmd_data + occ->seq_no + 1;
>         u8 cmd[8];
>         struct occ_poll_response_header *header;
>
>         /* big endian */
> -       cmd[0] = 0;                     /* sequence number */
> +       cmd[0] = occ->seq_no++;         /* sequence number */
>         cmd[1] = 0;                     /* cmd type */
>         cmd[2] = 0;                     /* data length msb */
>         cmd[3] = 1;                     /* data length lsb */
> diff --git a/drivers/hwmon/occ/common.h b/drivers/hwmon/occ/common.h
> index fc13f3c..67e6968 100644
> --- a/drivers/hwmon/occ/common.h
> +++ b/drivers/hwmon/occ/common.h
> @@ -95,6 +95,7 @@ struct occ {
>         struct occ_sensors sensors;
>
>         int powr_sample_time_us;        /* average power sample time */
> +       u8 seq_no;
>         u8 poll_cmd_data;               /* to perform OCC poll command */
>         int (*send_cmd)(struct occ *occ, u8 *cmd);
>
> --
> 1.8.3.1
>