2 files changed, 26 insertions, 1 deletions

diff --git a/Documentation/hwmon/w83781d b/Documentation/hwmon/w83781d
index ac155d8b0fef..b1e9f80098ee 100644
--- a/Documentation/hwmon/w83781d
+++ b/Documentation/hwmon/w83781d
@@ -36,6 +36,11 @@ Module parameters
   Use 'init=0' to bypass initializing the chip.
   Try this if your computer crashes when you load the module.
 
+* reset int
+  (default 0)
+  The driver used to reset the chip on load, but does no more. Use
+  'reset=1' to restore the old behavior. Report if you need to do this.
+
 force_subclients=bus,caddr,saddr,saddr
   This is used to force the i2c addresses for subclients of
   a certain chip. Typical usage is `force_subclients=0,0x2d,0x4a,0x4b'
diff --git a/drivers/hwmon/w83781d.c b/drivers/hwmon/w83781d.c
index 782117817526..8b17132f6b94 100644
--- a/drivers/hwmon/w83781d.c
+++ b/drivers/hwmon/w83781d.c
@@ -57,6 +57,10 @@ I2C_CLIENT_INSMOD_5(w83781d, w83782d, w83783s, w83627hf, as99127f);
 I2C_CLIENT_MODULE_PARM(force_subclients, "List of subclient addresses: "
                     "{bus, clientaddr, subclientaddr1, subclientaddr2}");
 
+static int reset;
+module_param(reset, bool, 0);
+MODULE_PARM_DESC(reset, "Set to one to reset chip on load");
+
 static int init = 1;
 module_param(init, bool, 0);
 MODULE_PARM_DESC(init, "Set to zero to bypass chip initialization");
@@ -1460,8 +1464,17 @@ w83781d_init_client(struct i2c_client *client)
         int type = data->type;
         u8 tmp;
 
-        if (init && type != as99127f) { /* this resets registers we don't have
+        if (reset && type != as99127f) { /* this resets registers we don't have
                                            documentation for on the as99127f */
+                /* Resetting the chip has been the default for a long time,
+                   but it causes the BIOS initializations (fan clock dividers,
+                   thermal sensor types...) to be lost, so it is now optional.
+                   It might even go away if nobody reports it as being useful,
+                   as I see very little reason why this would be needed at
+                   all. */
+                dev_info(&client->dev, "If reset=1 solved a problem you were "
+                         "having, please report!\n");
+
                 /* save these registers */
                 i = w83781d_read_value(client, W83781D_REG_BEEP_CONFIG);
                 p = w83781d_read_value(client, W83781D_REG_PWMCLK12);
@@ -1478,6 +1491,13 @@ w83781d_init_client(struct i2c_client *client)
                 w83781d_write_value(client, W83781D_REG_BEEP_INTS2, 0);
         }
 
+        /* Disable power-on abnormal beep, as advised by the datasheet.
+           Already done if reset=1. */
+        if (init && !reset && type != as99127f) {
+                i = w83781d_read_value(client, W83781D_REG_BEEP_CONFIG);
+                w83781d_write_value(client, W83781D_REG_BEEP_CONFIG, i | 0x80);
+        }
+
         data->vrm = vid_which_vrm();
 
         if ((type != w83781d) && (type != as99127f)) {