[PATCH 3.12 139/170] hwmon: (adm1029) Ensure the fan_div cache is updated in set_fan_div

[Jiri Slaby]

From: Axel Lin <axel.lin@xxxxxxxxxx>

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

===============

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: Jiri Slaby <jslaby@xxxxxxx>
---
 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);
-- 
2.0.0

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