From: David Daney <ddaney@caviumnetworks.com>
Date: Tue, 16 Nov 2010 22:42:14 +0000 (-0800)
Subject: of/i2c: Fix request module by alias
X-Git-Tag: firefly_0821_release~7613^2~3177^2~3
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=020862648445d7c1b12ea213c152f27def703f3b;p=firefly-linux-kernel-4.4.55.git

of/i2c: Fix request module by alias

If we are registering an i2c device that has a device tree node like
this real-world example:

      rtc@68 {
        compatible = "dallas,ds1337";
        reg = <0x68>;
      };

of_i2c_register_devices() will try to load a module called ds1337.ko.
There is no such module, so it will fail.  If we look in modules.alias
we will find entries like these:

.
.
.
alias i2c:ds1339 rtc_ds1307
alias i2c:ds1338 rtc_ds1307
alias i2c:ds1337 rtc_ds1307
alias i2c:ds1307 rtc_ds1307
alias i2c:ds1374 rtc_ds1374
.
.
.

The module we want is really called rtc_ds1307.ko.  If we request a
module called "i2c:ds1337", the userspace module loader will do the
right thing (unless it is busybox) and load rtc_ds1307.ko.  So we add
the I2C_MODULE_PREFIX to the request_module() string.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
---

diff --git a/drivers/of/of_i2c.c b/drivers/of/of_i2c.c
index c85d3c7421fc..f37fbeb66a44 100644
--- a/drivers/of/of_i2c.c
+++ b/drivers/of/of_i2c.c
@@ -61,7 +61,7 @@ void of_i2c_register_devices(struct i2c_adapter *adap)
 		info.of_node = of_node_get(node);
 		info.archdata = &dev_ad;
 
-		request_module("%s", info.type);
+		request_module("%s%s", I2C_MODULE_PREFIX, info.type);
 
 		result = i2c_new_device(adap, &info);
 		if (result == NULL) {