Currently of_i2c will select first compatible property as a last resort
option. This isn't best choice though, because generic compatible entries
are listed last, not first. For example, two compatible entries given for
the MCU node:

"fsl,mc9s08qg8-mpc837xrdb", "fsl,mcu-mpc8349emitx";

Since no sane driver will ever match specific devices, what we want is
to select most generic option (last). Then driver may call
of_device_is_compatible() if it is really interested in details.

Signed-off-by: Anton Vorontsov <[EMAIL PROTECTED]>
---

Other options are: start filling the exceptions list, or add  "linux,..."
compatible entry to the device tree.

 drivers/of/of_i2c.c |   17 +++++++++++------
 1 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/of/of_i2c.c b/drivers/of/of_i2c.c
index b2ccdcb..0d35a0a 100644
--- a/drivers/of/of_i2c.c
+++ b/drivers/of/of_i2c.c
@@ -29,6 +29,7 @@ static int of_find_i2c_driver(struct device_node *node,
        int i, cplen;
        const char *compatible;
        const char *p;
+       const char *last_wcomma = NULL;
 
        /* 1. search for exception list entry */
        for (i = 0; i < ARRAY_SIZE(i2c_devices); i++) {
@@ -45,7 +46,7 @@ static int of_find_i2c_driver(struct device_node *node,
        if (!compatible)
                return -ENODEV;
 
-       /* 2. search for linux,<i2c-type> entry */
+       /* 2. search for linux,<i2c-type> entry, or remember last w/ comma */
        p = compatible;
        while (cplen > 0) {
                if (!strncmp(p, "linux,", 6)) {
@@ -54,6 +55,12 @@ static int of_find_i2c_driver(struct device_node *node,
                                    I2C_NAME_SIZE) >= I2C_NAME_SIZE)
                                return -ENOMEM;
                        return 0;
+               } else {
+                       const char *comma;
+
+                       comma = strchr(p, ',');
+                       if (comma)
+                               last_wcomma = comma + 1;
                }
 
                i = strlen(p) + 1;
@@ -61,12 +68,10 @@ static int of_find_i2c_driver(struct device_node *node,
                cplen -= i;
        }
 
-       /* 3. take fist compatible entry and strip manufacturer */
-       p = strchr(compatible, ',');
-       if (!p)
+       /* 3. take last compatible entry w/ comma, manufacturer stripped */
+       if (!last_wcomma)
                return -ENODEV;
-       p++;
-       if (strlcpy(info->type, p, I2C_NAME_SIZE) >= I2C_NAME_SIZE)
+       if (strlcpy(info->type, last_wcomma, I2C_NAME_SIZE) >= I2C_NAME_SIZE)
                return -ENOMEM;
        return 0;
 }
-- 
1.5.5.4
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