[PATCH] OCC: FSI and hwmon: Add sequence numbering

From: Eddie James
Date: Wed Jun 26 2019 - 15:14:22 EST


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@xxxxxxxxxxxxx>
---
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 d593517..a7d2b16 100644
--- a/drivers/hwmon/occ/common.c
+++ b/drivers/hwmon/occ/common.c
@@ -124,12 +124,12 @@ 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