[PATCH v4 1/4] Input: adp5589: Add default platform data

[Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>]

From: Lars-Peter Clausen <lars@xxxxxxxxxx>

If no platform data is supplied use a dummy platform data that configures
the device in GPIO only mode. This change adds a adp5589_kpad_pdata_get()
helper that returns the default platform-data. This can be later extended
to load configuration from device-trees or ACPI.

Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
---

Changelog v3 -> v4:
* Fixed smatch warnings about potential leak being created; resulted in 2
  more patches:
  - Input: adp5589: unify ret & error variables
  - Input: adp5589: fix possible memleak of 'kpad'

Changelog v2 -> v3:
* fix `-Wpointer-to-int-cast` warnings for patch `input: adp5589: Add basic
  devicetree support` ; warnings shows up on 64 bit ARCHs

Changelog v1 -> v2:
* adjusted patch `input: adp5589: Add default platform data` by
  introducting a `adp5589_kpad_pdata_get()` helper, which returns the
  platform-data; the previos patch was based on an older version of the
  kernel from the ADI kernel-tree; the driver was sync-ed with the upstream
  version

 drivers/input/keyboard/adp5589-keys.c | 36 +++++++++++++++++++--------
 1 file changed, 26 insertions(+), 10 deletions(-)

diff --git a/drivers/input/keyboard/adp5589-keys.c b/drivers/input/keyboard/adp5589-keys.c
index e7d58e7f0257..c6a801bcdf90 100644
--- a/drivers/input/keyboard/adp5589-keys.c
+++ b/drivers/input/keyboard/adp5589-keys.c
@@ -369,6 +369,25 @@ static const struct adp_constants const_adp5585 = {
 	.reg			= adp5585_reg,
 };
 
+static const struct adp5589_gpio_platform_data adp5589_default_gpio_pdata = {
+	.gpio_start = -1,
+};
+
+static const struct adp5589_kpad_platform_data adp5589_default_pdata = {
+	.gpio_data = &adp5589_default_gpio_pdata,
+};
+
+static const struct adp5589_kpad_platform_data *adp5589_kpad_pdata_get(
+	struct device *dev)
+{
+	const struct adp5589_kpad_platform_data *pdata = dev_get_platdata(dev);
+
+	if (!pdata)
+		pdata = &adp5589_default_pdata;
+
+	return pdata;
+}
+
 static int adp5589_read(struct i2c_client *client, u8 reg)
 {
 	int ret = i2c_smbus_read_byte_data(client, reg);
@@ -498,7 +517,8 @@ static int adp5589_build_gpiomap(struct adp5589_kpad *kpad,
 static int adp5589_gpio_add(struct adp5589_kpad *kpad)
 {
 	struct device *dev = &kpad->client->dev;
-	const struct adp5589_kpad_platform_data *pdata = dev_get_platdata(dev);
+	const struct adp5589_kpad_platform_data *pdata =
+		adp5589_kpad_pdata_get(dev);
 	const struct adp5589_gpio_platform_data *gpio_data = pdata->gpio_data;
 	int i, error;
 
@@ -553,7 +573,8 @@ static int adp5589_gpio_add(struct adp5589_kpad *kpad)
 static void adp5589_gpio_remove(struct adp5589_kpad *kpad)
 {
 	struct device *dev = &kpad->client->dev;
-	const struct adp5589_kpad_platform_data *pdata = dev_get_platdata(dev);
+	const struct adp5589_kpad_platform_data *pdata =
+		adp5589_kpad_pdata_get(dev);
 	const struct adp5589_gpio_platform_data *gpio_data = pdata->gpio_data;
 	int error;
 
@@ -656,7 +677,7 @@ static int adp5589_setup(struct adp5589_kpad *kpad)
 {
 	struct i2c_client *client = kpad->client;
 	const struct adp5589_kpad_platform_data *pdata =
-		dev_get_platdata(&client->dev);
+		adp5589_kpad_pdata_get(&client->dev);
 	u8 (*reg) (u8) = kpad->var->reg;
 	unsigned char evt_mode1 = 0, evt_mode2 = 0, evt_mode3 = 0;
 	unsigned char pull_mask = 0;
@@ -861,7 +882,7 @@ static int adp5589_keypad_add(struct adp5589_kpad *kpad, unsigned int revid)
 {
 	struct i2c_client *client = kpad->client;
 	const struct adp5589_kpad_platform_data *pdata =
-		dev_get_platdata(&client->dev);
+		adp5589_kpad_pdata_get(&client->dev);
 	struct input_dev *input;
 	unsigned int i;
 	int error;
@@ -992,7 +1013,7 @@ static int adp5589_probe(struct i2c_client *client,
 {
 	struct adp5589_kpad *kpad;
 	const struct adp5589_kpad_platform_data *pdata =
-		dev_get_platdata(&client->dev);
+		adp5589_kpad_pdata_get(&client->dev);
 	unsigned int revid;
 	int error, ret;
 
@@ -1002,11 +1023,6 @@ static int adp5589_probe(struct i2c_client *client,
 		return -EIO;
 	}
 
-	if (!pdata) {
-		dev_err(&client->dev, "no platform data?\n");
-		return -EINVAL;
-	}
-
 	kpad = kzalloc(sizeof(*kpad), GFP_KERNEL);
 	if (!kpad)
 		return -ENOMEM;
-- 
2.20.1