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 <[email protected]> Index: linux.git3/drivers/gpio/max7301.c =================================================================== --- linux.git3.orig/drivers/gpio/max7301.c 2008-10-22 09:50:45.000000000 +0100 +++ linux.git3/drivers/gpio/max7301.c 2009-01-07 12:37:46.000000000 +0000 @@ -217,8 +217,10 @@ static int __devinit max7301_probe(struc 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 Index: linux.git3/drivers/gpio/max732x.c =================================================================== --- linux.git3.orig/drivers/gpio/max732x.c 2008-10-22 09:50:45.000000000 +0100 +++ linux.git3/drivers/gpio/max732x.c 2009-01-07 12:22:10.000000000 +0000 @@ -267,8 +267,10 @@ static int __devinit max732x_probe(struc 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) Index: linux.git3/drivers/gpio/mcp23s08.c =================================================================== --- linux.git3.orig/drivers/gpio/mcp23s08.c 2008-10-22 09:50:45.000000000 +0100 +++ linux.git3/drivers/gpio/mcp23s08.c 2009-01-07 12:23:24.000000000 +0000 @@ -310,8 +310,10 @@ static int mcp23s08_probe(struct spi_dev 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) Index: linux.git3/drivers/gpio/pca953x.c =================================================================== --- linux.git3.orig/drivers/gpio/pca953x.c 2008-10-22 09:50:45.000000000 +0100 +++ linux.git3/drivers/gpio/pca953x.c 2009-01-07 12:36:00.000000000 +0000 @@ -200,8 +200,10 @@ static int __devinit pca953x_probe(struc 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) Index: linux.git3/drivers/gpio/pcf857x.c =================================================================== --- linux.git3.orig/drivers/gpio/pcf857x.c 2008-10-22 09:50:45.000000000 +0100 +++ linux.git3/drivers/gpio/pcf857x.c 2009-01-07 12:27:00.000000000 +0000 @@ -188,8 +188,10 @@ static int pcf857x_probe(struct i2c_clie 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_clie 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; -- Ben ([email protected], http://www.fluff.org/) 'a smiley only costs 4 bytes' ------------------------------------------------------------------------------ Check out the new SourceForge.net Marketplace. It is the best place to buy or sell services for just about anything Open Source. http://p.sf.net/sfu/Xq1LFB _______________________________________________ spi-devel-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/spi-devel-general
