From a342d215c206d955fea55d778e3803b29ee41b60 Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Thu, 15 Jan 2009 13:50:45 -0800 Subject: [PATCH] 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 Cc: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/gpio/max7301.c | 6 ++++-- drivers/gpio/max732x.c | 6 ++++-- drivers/gpio/mcp23s08.c | 6 ++++-- drivers/gpio/pca953x.c | 6 ++++-- drivers/gpio/pcf857x.c | 12 ++++++++---- 5 files changed, 24 insertions(+), 12 deletions(-) diff --git a/drivers/gpio/max7301.c b/drivers/gpio/max7301.c index 8b24d784db93..3e7f4e06386e 100644 --- a/drivers/gpio/max7301.c +++ b/drivers/gpio/max7301.c @@ -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 diff --git a/drivers/gpio/max732x.c b/drivers/gpio/max732x.c index 55ae9a41897a..f7868243af89 100644 --- a/drivers/gpio/max732x.c +++ b/drivers/gpio/max732x.c @@ -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) diff --git a/drivers/gpio/mcp23s08.c b/drivers/gpio/mcp23s08.c index 89c1d222e9d1..f6fae0e50e65 100644 --- a/drivers/gpio/mcp23s08.c +++ b/drivers/gpio/mcp23s08.c @@ -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) diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c index 37f35388a2ae..8dc0164bd51e 100644 --- a/drivers/gpio/pca953x.c +++ b/drivers/gpio/pca953x.c @@ -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) diff --git a/drivers/gpio/pcf857x.c b/drivers/gpio/pcf857x.c index 4bc2070dd4a1..9525724be731 100644 --- a/drivers/gpio/pcf857x.c +++ b/drivers/gpio/pcf857x.c @@ -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;