From 1648505d1353ab336bfe3165b6765d179b14c815 Mon Sep 17 00:00:00 2001 From: Eddie James Date: Thu, 29 Apr 2021 10:13:36 -0500 Subject: [PATCH] hwmon: (occ) Fix poll rate limiting [ Upstream commit 5216dff22dc2bbbbe6f00335f9fd2879670e753b ] The poll rate limiter time was initialized at zero. This breaks the comparison in time_after if jiffies is large. Switch to storing the next update time rather than the previous time, and initialize the time when the device is probed. Fixes: c10e753d43eb ("hwmon (occ): Add sensor types and versions") Signed-off-by: Eddie James Link: https://lore.kernel.org/r/20210429151336.18980-1-eajames@linux.ibm.com Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/occ/common.c | 5 +++-- drivers/hwmon/occ/common.h | 2 +- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/hwmon/occ/common.c b/drivers/hwmon/occ/common.c index 30e18eb60da7..0b689ccbb793 100644 --- a/drivers/hwmon/occ/common.c +++ b/drivers/hwmon/occ/common.c @@ -209,9 +209,9 @@ int occ_update_response(struct occ *occ) return rc; /* limit the maximum rate of polling the OCC */ - if (time_after(jiffies, occ->last_update + OCC_UPDATE_FREQUENCY)) { + if (time_after(jiffies, occ->next_update)) { rc = occ_poll(occ); - occ->last_update = jiffies; + occ->next_update = jiffies + OCC_UPDATE_FREQUENCY; } else { rc = occ->last_error; } @@ -1089,6 +1089,7 @@ int occ_setup(struct occ *occ, const char *name) return rc; } + occ->next_update = jiffies + OCC_UPDATE_FREQUENCY; occ_parse_poll_response(occ); rc = occ_setup_sensor_attrs(occ); diff --git a/drivers/hwmon/occ/common.h b/drivers/hwmon/occ/common.h index 67e6968b8978..e6df719770e8 100644 --- a/drivers/hwmon/occ/common.h +++ b/drivers/hwmon/occ/common.h @@ -99,7 +99,7 @@ struct occ { u8 poll_cmd_data; /* to perform OCC poll command */ int (*send_cmd)(struct occ *occ, u8 *cmd); - unsigned long last_update; + unsigned long next_update; struct mutex lock; /* lock OCC access */ struct device *hwmon;