[PATCH v3] gpio: vt8500: memory cleanup missing

From: Tony Prisk
Date: Thu Jan 17 2013 - 23:57:51 EST


This driver is missing a .remove callback, and the fail path on
probe is incomplete.

If an error occurs in vt8500_add_chips, gpio_base is not unmapped.
The driver is also ignoring the return value from this function so
if a chip fails to register it completes as successful.

Replaced pr_err with dev_err in vt8500_add_chips since the device is
available.

There is also no .remove callback defined so the function is added.

Signed-off-by: Tony Prisk <linux@xxxxxxxxxxxxxxx>
---
v2:
Remove global vtchip and store pointer in platform_data - As pointed out by
Russell King.

v3:
Following problems pointed out by Grant Likely:

Removed unnecessary whitespace change.
Removed test against pdev->dev.of_node (np). Replaced code with a
devm_request_and_ioremap so np is now unneccessary. This also removes the need
for cleanup in the fail path.
Move struct vt8500_gpio_chip within vt8500_data and store the iobase and
num_banks in vt8500_data.


drivers/gpio/gpio-vt8500.c | 61 +++++++++++++++++++++++++++++++++++---------
1 file changed, 49 insertions(+), 12 deletions(-)

diff --git a/drivers/gpio/gpio-vt8500.c b/drivers/gpio/gpio-vt8500.c
index b53320a..5c8cd7c 100644
--- a/drivers/gpio/gpio-vt8500.c
+++ b/drivers/gpio/gpio-vt8500.c
@@ -127,6 +127,12 @@ struct vt8500_gpio_chip {
void __iomem *base;
};

+struct vt8500_data {
+ struct vt8500_gpio_chip *chip;
+ void __iomem *iobase;
+ int num_banks;
+};
+

#define to_vt8500(__chip) container_of(__chip, struct vt8500_gpio_chip, chip)

@@ -224,19 +230,32 @@ static int vt8500_of_xlate(struct gpio_chip *gc,
static int vt8500_add_chips(struct platform_device *pdev, void __iomem *base,
const struct vt8500_gpio_data *data)
{
+ struct vt8500_data *priv;
struct vt8500_gpio_chip *vtchip;
struct gpio_chip *chip;
int i;
int pin_cnt = 0;

- vtchip = devm_kzalloc(&pdev->dev,
+ priv = devm_kzalloc(&pdev->dev, sizeof(struct vt8500_data), GFP_KERNEL);
+ if (!priv) {
+ dev_err(&pdev->dev, "failed to allocate memory\n");
+ return -ENOMEM;
+ }
+
+ priv->chip = devm_kzalloc(&pdev->dev,
sizeof(struct vt8500_gpio_chip) * data->num_banks,
GFP_KERNEL);
- if (!vtchip) {
- pr_err("%s: failed to allocate chip memory\n", __func__);
+ if (!priv->chip) {
+ dev_err(&pdev->dev, "failed to allocate chip memory\n");
return -ENOMEM;
}

+ priv->iobase = base;
+ priv->num_banks = data->num_banks;
+ platform_set_drvdata(pdev, priv);
+
+ vtchip = priv->chip;
+
for (i = 0; i < data->num_banks; i++) {
vtchip[i].base = base;
vtchip[i].regs = &data->banks[i];
@@ -273,36 +292,54 @@ static struct of_device_id vt8500_gpio_dt_ids[] = {

static int vt8500_gpio_probe(struct platform_device *pdev)
{
+ int ret;
void __iomem *gpio_base;
- struct device_node *np;
+ struct resource *res;
const struct of_device_id *of_id =
of_match_device(vt8500_gpio_dt_ids, &pdev->dev);

if (!of_id) {
- dev_err(&pdev->dev, "Failed to find gpio controller\n");
+ dev_err(&pdev->dev, "No matching driver data\n");
return -ENODEV;
}

- np = pdev->dev.of_node;
- if (!np) {
- dev_err(&pdev->dev, "Missing GPIO description in devicetree\n");
- return -EFAULT;
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "Unable to get IO resource\n");
+ return -ENODEV;
}

- gpio_base = of_iomap(np, 0);
+ gpio_base = devm_request_and_ioremap(&pdev->dev, res);
if (!gpio_base) {
dev_err(&pdev->dev, "Unable to map GPIO registers\n");
- of_node_put(np);
return -ENOMEM;
}

- vt8500_add_chips(pdev, gpio_base, of_id->data);
+ ret = vt8500_add_chips(pdev, gpio_base, of_id->data);
+
+ return ret;
+}
+
+static int vt8500_gpio_remove(struct platform_device *pdev)
+{
+ int i;
+ int ret;
+ struct vt8500_data *priv = platform_get_drvdata(pdev);
+ struct vt8500_gpio_chip *vtchip = priv->chip;
+
+ for (i = 0; i < priv->num_banks; i++) {
+ ret = gpiochip_remove(&vtchip[i].chip);
+ if (ret)
+ dev_warn(&pdev->dev, "gpiochip_remove returned %d\n",
+ ret);
+ }

return 0;
}

static struct platform_driver vt8500_gpio_driver = {
.probe = vt8500_gpio_probe,
+ .remove = vt8500_gpio_remove,
.driver = {
.name = "vt8500-gpio",
.owner = THIS_MODULE,
--
1.7.9.5

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