gpio: fix probe() error return in gpio driver probes

A number of drivers in drivers/gpio return -ENODEV when confronted with
missing setup parameters such as the platform data.  However, returning
-ENODEV causes the driver layer to silently ignore the driver as it
assumes the probe did not find anything and was only speculative.

To make life easier to discern why a driver is not being attached, change
to returning -EINVAL, which is a better description of the fact that the
driver data was not valid.

Also add a set of dev_dbg() statements to the error paths to provide an
better explanation of the error as there may be more that one point in the
driver.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Ben Dooks 2009-01-15 13:50:45 -08:00 committed by Linus Torvalds
parent 5b96f17290
commit a342d215c2
5 changed files with 24 additions and 12 deletions

View file

@ -217,8 +217,10 @@ static int __devinit max7301_probe(struct spi_device *spi)
int i, ret;
pdata = spi->dev.platform_data;
if (!pdata || !pdata->base)
return -ENODEV;
if (!pdata || !pdata->base) {
dev_dbg(&spi->dev, "incorrect or missing platform data\n");
return -EINVAL;
}
/*
* bits_per_word cannot be configured in platform data

View file

@ -267,8 +267,10 @@ static int __devinit max732x_probe(struct i2c_client *client,
int ret, nr_port;
pdata = client->dev.platform_data;
if (pdata == NULL)
return -ENODEV;
if (pdata == NULL) {
dev_dbg(&client->dev, "no platform data\n");
return -EINVAL;
}
chip = kzalloc(sizeof(struct max732x_chip), GFP_KERNEL);
if (chip == NULL)

View file

@ -310,8 +310,10 @@ static int mcp23s08_probe(struct spi_device *spi)
unsigned base;
pdata = spi->dev.platform_data;
if (!pdata || !gpio_is_valid(pdata->base))
return -ENODEV;
if (!pdata || !gpio_is_valid(pdata->base)) {
dev_dbg(&spi->dev, "invalid or missing platform data\n");
return -EINVAL;
}
for (addr = 0; addr < 4; addr++) {
if (!pdata->chip[addr].is_present)

View file

@ -202,8 +202,10 @@ static int __devinit pca953x_probe(struct i2c_client *client,
int ret;
pdata = client->dev.platform_data;
if (pdata == NULL)
return -ENODEV;
if (pdata == NULL) {
dev_dbg(&client->dev, "no platform data\n");
return -EINVAL;
}
chip = kzalloc(sizeof(struct pca953x_chip), GFP_KERNEL);
if (chip == NULL)

View file

@ -188,8 +188,10 @@ static int pcf857x_probe(struct i2c_client *client,
int status;
pdata = client->dev.platform_data;
if (!pdata)
return -ENODEV;
if (!pdata) {
dev_dbg(&client->dev, "no platform data\n");
return -EINVAL;
}
/* Allocate, initialize, and register this gpio_chip. */
gpio = kzalloc(sizeof *gpio, GFP_KERNEL);
@ -248,8 +250,10 @@ static int pcf857x_probe(struct i2c_client *client,
else
status = i2c_read_le16(client);
} else
status = -ENODEV;
} else {
dev_dbg(&client->dev, "unsupported number of gpios\n");
status = -EINVAL;
}
if (status < 0)
goto fail;