[PATCH 3.11 094/128] hwmon: (adm1029) Ensure the fan_div cache is updated in set_fan_div

From: Luis Henriques
Date: Thu Jul 24 2014 - 05:48:48 EST


3.11.10.14 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Axel Lin <axel.lin@xxxxxxxxxx>

commit 1035a9e3e9c76b64a860a774f5b867d28d34acc2 upstream.

Writing to fanX_div does not clear the cache. As a result, reading
from fanX_div may return the old value for up to two seconds
after writing a new value.

This patch ensures the fan_div cache is updated in set_fan_div().

Reported-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Axel Lin <axel.lin@xxxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
drivers/hwmon/adm1029.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/hwmon/adm1029.c b/drivers/hwmon/adm1029.c
index 9ee5e066423b..39441e5d922c 100644
--- a/drivers/hwmon/adm1029.c
+++ b/drivers/hwmon/adm1029.c
@@ -232,6 +232,9 @@ static ssize_t set_fan_div(struct device *dev,
/* Update the value */
reg = (reg & 0x3F) | (val << 6);

+ /* Update the cache */
+ data->fan_div[attr->index] = reg;
+
/* Write value */
i2c_smbus_write_byte_data(client,
ADM1029_REG_FAN_DIV[attr->index], reg);
--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/