[PATCH v2 2/6] of: Return -ENXIO from of_parse_phandle_with_args for too large index and return errors from of_gpio_named_count

Andreas Larsson
2013-01-29T14:53:56Z

This lets of_gpio_named_count return an errno on errors by being able to
distinguish between reaching the end of the phandle list and getting some other
error from of_parse_phandle_with_args.

Return error from of_spi_register_master when there is an "cs-gpios" list for
which gp_gpio_named_count fails.

Adjust various drivers cope with error return from of_gpio_named_count,
including via of_gpio_count.

Signed-off-by: Andreas Larsson <andreas@gaisler.com>
---
Changes since v1:
- Handle error return values from calls to of_gpio_count

drivers/gpio/gpiolib-of.c | 8 +++++---
drivers/hwmon/gpio-fan.c | 6 +++---
drivers/i2c/muxes/i2c-mux-gpio.c | 3 ++-
drivers/input/keyboard/matrix_keypad.c | 2 +-
drivers/net/phy/mdio-mux-gpio.c | 2 +-
drivers/of/base.c | 5 ++++-
drivers/spi/spi-fsl-spi.c | 4 +++-
drivers/spi/spi-mpc52xx.c | 5 +++++
drivers/spi/spi-oc-tiny.c | 4 +++-
drivers/spi/spi-ppc4xx.c | 6 +++++-
drivers/spi/spi.c | 11 +++++++----
11 files changed, 39 insertions(+), 17 deletions(-)

diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index d542a14..28f24a6 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -107,11 +107,10 @@ EXPORT_SYMBOL(of_get_named_gpio_flags);
*/
unsigned int of_gpio_named_count(struct device_node *np, const char* propname)
{
+ int ret;
unsigned int cnt = 0;

do {
- int ret;
-
ret = of_parse_phandle_with_args(np, propname, "#gpio-cells",
cnt, NULL);
/* A hole in the gpios = <> counts anyway. */
@@ -119,7 +118,10 @@ unsigned int of_gpio_named_count(struct device_node *np, const char* propname)
break;
} while (++cnt);

- return cnt;
+ if (ret == -ENXIO)
+ return cnt;
+ else
+ return ret;
}
EXPORT_SYMBOL(of_gpio_named_count);

diff --git a/drivers/hwmon/gpio-fan.c b/drivers/hwmon/gpio-fan.c
index 4e04c12..9b92d34 100644
--- a/drivers/hwmon/gpio-fan.c
+++ b/drivers/hwmon/gpio-fan.c
@@ -422,8 +422,8 @@ static int gpio_fan_get_of_pdata(struct device *dev,

/* Fill GPIO pin array */
pdata->num_ctrl = of_gpio_count(node);
- if (!pdata->num_ctrl) {
- dev_err(dev, "gpios DT property empty / missing");
+ if (pdata->num_ctrl <= 0) {
+ dev_err(dev, "gpios DT property broken / empty / missing");
return -ENODEV;
}
ctrl = devm_kzalloc(dev, pdata->num_ctrl * sizeof(unsigned),
@@ -477,7 +477,7 @@ static int gpio_fan_get_of_pdata(struct device *dev,
pdata->speed = speed;

/* Alarm GPIO if one exists */
- if (of_gpio_named_count(node, "alarm-gpios")) {
+ if (of_gpio_named_count(node, "alarm-gpios") > 0) {
struct gpio_fan_alarm *alarm;
int val;
enum of_gpio_flags flags;
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index 9272743..a3ddb36 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -106,7 +106,8 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux,

mux->data.n_gpios = of_gpio_named_count(np, "mux-gpios");
if (mux->data.n_gpios < 0) {
- dev_err(&pdev->dev, "Missing mux-gpios property in the DT.\n");
+ dev_err(&pdev->dev,
+ "Missing or broken mux-gpios property in the DT.\n");
return -EINVAL;
}

diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
index f4ff0dd..bc7cec5 100644
--- a/drivers/input/keyboard/matrix_keypad.c
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -418,7 +418,7 @@ matrix_keypad_parse_dt(struct device *dev)

pdata->num_row_gpios = of_gpio_named_count(np, "row-gpios");
pdata->num_col_gpios = of_gpio_named_count(np, "col-gpios");
- if (!pdata->num_row_gpios || !pdata->num_col_gpios) {
+ if (pdata->num_row_gpios <= 0 || !pdata->num_col_gpios <= 0) {
dev_err(dev, "number of keypad rows/columns not specified\n");
return ERR_PTR(-EINVAL);
}
diff --git a/drivers/net/phy/mdio-mux-gpio.c b/drivers/net/phy/mdio-mux-gpio.c
index 0c9accb..3e1d285 100644
--- a/drivers/net/phy/mdio-mux-gpio.c
+++ b/drivers/net/phy/mdio-mux-gpio.c
@@ -61,7 +61,7 @@ static int mdio_mux_gpio_probe(struct platform_device *pdev)
return -ENODEV;

num_gpios = of_gpio_count(pdev->dev.of_node);
- if (num_gpios == 0 || num_gpios > MDIO_MUX_GPIO_MAX_BITS)
+ if (num_gpios <= 0 || num_gpios > MDIO_MUX_GPIO_MAX_BITS)
return -ENODEV;

s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 986afd7..1f16629 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1110,7 +1110,10 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
/* Loop exited without finding a valid entry; return an error */
if (node)
of_node_put(node);
- return -EINVAL;
+ if (list == list_end)
+ return -ENXIO; /* Index beyond end of list */
+ else
+ return -EINVAL;
}
EXPORT_SYMBOL(of_parse_phandle_with_args);

diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c
index 1a7f635..9dcfeed 100644
--- a/drivers/spi/spi-fsl-spi.c
+++ b/drivers/spi/spi-fsl-spi.c
@@ -952,13 +952,15 @@ static int of_fsl_spi_get_chipselects(struct device *dev)
int ret;

ngpios = of_gpio_count(np);
- if (!ngpios) {
+ if (!ngpios || ngpios == -ENOENT) {
/*
* SPI w/o chip-select line. One SPI device is still permitted
* though.
*/
pdata->max_chipselect = 1;
return 0;
+ } else if (ngpios < 0) {
+ return ngpios;
}

pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL);
diff --git a/drivers/spi/spi-mpc52xx.c b/drivers/spi/spi-mpc52xx.c
index 29f7705..e945195 100644
--- a/drivers/spi/spi-mpc52xx.c
+++ b/drivers/spi/spi-mpc52xx.c
@@ -478,6 +478,11 @@ static int mpc52xx_spi_probe(struct platform_device *op)
gpio_direction_output(gpio_cs, 1);
ms->gpio_cs[i] = gpio_cs;
}
+ } else if (ms->gpio_cs_count < 0 && ms->gpio_cs_count != -ENOENT) {
+ dev_err(&op->dev,
+ "could not count the gpio field entries in oftree\n");
+ rc = ms->gpio_cs_count;
+ goto err_alloc_gpio;
}

spin_lock_init(&ms->lock);
diff --git a/drivers/spi/spi-oc-tiny.c b/drivers/spi/spi-oc-tiny.c
index 432e66e..d1a7151 100644
--- a/drivers/spi/spi-oc-tiny.c
+++ b/drivers/spi/spi-oc-tiny.c
@@ -254,12 +254,14 @@ static int tiny_spi_of_probe(struct platform_device *pdev)
if (!np)
return 0;
hw->gpio_cs_count = of_gpio_count(np);
- if (hw->gpio_cs_count) {
+ if (hw->gpio_cs_count > 0) {
hw->gpio_cs = devm_kzalloc(&pdev->dev,
hw->gpio_cs_count * sizeof(unsigned int),
GFP_KERNEL);
if (!hw->gpio_cs)
return -ENOMEM;
+ } else if (hw->gpio_cs_count < 0 && hw->gpio_cs_count != -ENOENT) {
+ return hw->gpio_cs_count;
}
for (i = 0; i < hw->gpio_cs_count; i++) {
hw->gpio_cs[i] = of_get_gpio_flags(np, i, NULL);
diff --git a/drivers/spi/spi-ppc4xx.c b/drivers/spi/spi-ppc4xx.c
index 7a85f22..b5243c5 100644
--- a/drivers/spi/spi-ppc4xx.c
+++ b/drivers/spi/spi-ppc4xx.c
@@ -419,7 +419,7 @@ static int __init spi_ppc4xx_of_probe(struct platform_device *op)
* This includes both "null" gpio's and real ones.
*/
num_gpios = of_gpio_count(np);
- if (num_gpios) {
+ if (num_gpios > 0) {
int i;

hw->gpios = kzalloc(sizeof(int) * num_gpios, GFP_KERNEL);
@@ -454,6 +454,10 @@ static int __init spi_ppc4xx_of_probe(struct platform_device *op)
goto free_gpios;
}
}
+ } else if (num_gpios < 0 && num_gpios != -ENOENT) {
+ dev_err(dev, "could not count gpio field entries\n");
+ ret = num_gpios;
+ goto free_master;
}

/* Setup the state for the bitbang driver */
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 19ee901..9c2acf1 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1059,7 +1059,7 @@ EXPORT_SYMBOL_GPL(spi_alloc_master);
#ifdef CONFIG_OF
static int of_spi_register_master(struct spi_master *master)
{
- u16 nb;
+ int nb;
int i, *cs;
struct device_node *np = master->dev.of_node;

@@ -1067,10 +1067,13 @@ static int of_spi_register_master(struct spi_master *master)
return 0;

nb = of_gpio_named_count(np, "cs-gpios");
- master->num_chipselect = max(nb, master->num_chipselect);
-
- if (nb < 1)
+ if (nb == 0 || nb == -ENOENT) /* No error if cs-gpios does not exist */
return 0;
+ else if (nb < 0)
+ return nb;
+
+ if (nb > master->num_chipselect)
+ master->num_chipselect = (u16)nb;

cs = devm_kzalloc(&master->dev,
sizeof(int) * master->num_chipselect,
--
1.7.0.4