New to C language, from looking at the code I cannot figure out how to initialize p_data. From what I can figure out p_data is part of a structure.
Can someone explain how to initialize p_data?
#ifdef CUST_LGE_TOUCH_BRING_UP
struct synaptics_rmi4_data *rmi4_data;
struct synaptics_rmi4_device_info *rmi;
const struct synaptics_dsx_board_data *platform_data =
client->dev.platform_data;
struct synaptics_dsx_board_data *p_data;
printk("[Touch] %s START!!!!!!!!!!!!!!\n",__func__);
#endif
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_BYTE_DATA)) {
dev_err(&client->dev,
"%s: SMBus byte data commands not supported by host\n",
__func__);
return -EIO;
}
#ifdef CUST_LGE_TOUCH_BRING_UP
rmi4_data = kzalloc(sizeof(*rmi4_data), GFP_KERNEL);
if (!rmi4_data) {
dev_err(&client->dev,
"%s: Failed to alloc mem for rmi4_data\n",
__func__);
return -ENOMEM;
}
#endif
synaptics_dsx_i2c_device = kzalloc(
sizeof(struct platform_device),
GFP_KERNEL);
if (!synaptics_dsx_i2c_device) {
dev_err(&client->dev,
"%s: Failed to allocate memory for synaptics_dsx_i2c_device\n",
__func__);
ret = -ENOMEM;
goto err_alloc_dsx_i2c_device;
}
#ifdef CUST_LGE_TOUCH_BRING_UP
if (client->dev.of_node) {
p_data = devm_kzalloc(&client->dev,
sizeof(struct synaptics_dsx_board_data), GFP_KERNEL);
if (!p_data) {
dev_err(&client->dev, "%s : Failed to allocate memory\n", __func__);
ret = -ENOMEM;
goto error_alloc_dsx_board_data;
}
retval = synaptics_rmi4_parse_dt(&client->dev, p_data);
platform_data = p_data;
client->dev.platform_data = p_data;
if (retval) {
printk("%s : Failed to parse device Tree",__func__);
ret = retval;
goto error;
}
} else {
platform_data = client->dev.platform_data;
if (!platform_data) {
printk("%s : Failed to copy platform_data\n", __func__);
retval = -EINVAL;
}
}
printk("%s: Probing i2c RMI device, addr: 0x%02x\n", __func__, client->addr);
rmi = &(rmi4_data->rmi4_mod_info);
if (!platform_data) {
dev_err(&client->dev,
"%s: No platform data found\n",
__func__);
ret = -EINVAL;
goto error;
}
printk("[Touch D] x_flip = %d\n", platform_data->x_flip);
printk("[Touch D] y_flip = %d\n", platform_data->y_flip);
printk("[Touch D] regulator_en = %d\n", platform_data->regulator_en);
printk("[Touch D] reset_gpio = %d\n", platform_data->reset_gpio);
printk("[Touch D] irq_gpio = %d\n", platform_data->irq_gpio);
printk("[Touch D] irq_flags = %lx\n", platform_data->irq_flags);
printk("[Touch D] panel_x = %d\n", platform_data->panel_x);
printk("[Touch D] panel_y = %d\n", platform_data->panel_y);
printk("[Touch D] reset_delay_ms = %d\n", platform_data->reset_delay_ms);
if (platform_data->regulator_en) {
rmi4_data->vreg_l22 = regulator_get(&client->dev, "vdd_ana");
if (IS_ERR(rmi4_data->vreg_l22)) {
dev_err(&client->dev,
"%s: Failed to get regulator vreg_l22\n",
__func__);
retval = PTR_ERR(rmi4_data->vreg_l22);
ret = -retval;
goto error;
}
regulator_set_voltage(rmi4_data->vreg_l22, 3300000, 3300000);
regulator_enable(rmi4_data->vreg_l22);
rmi4_data->vreg_lvs3 = regulator_get(&client->dev, "vcc_i2c");
if (IS_ERR(rmi4_data->vreg_lvs3)) {
dev_err(&client->dev,
"%s: Failed to get regulator vreg_l22\n",
__func__);
retval = PTR_ERR(rmi4_data->vreg_lvs3);
ret = -retval;
goto error;
}
regulator_enable(rmi4_data->vreg_lvs3);
}else
rmi4_power_on(client, 1);
msleep(400);
printk("[Touch D] %s : Done regulator set!!! \n",__func__);
#endif
hw_if.board_data = client->dev.platform_data;
hw_if.bus_access = &bus_access;
synaptics_dsx_i2c_device->name = PLATFORM_DRIVER_NAME;
synaptics_dsx_i2c_device->id = 0;
synaptics_dsx_i2c_device->num_resources = 0;
synaptics_dsx_i2c_device->dev.parent = &client->dev;
synaptics_dsx_i2c_device->dev.platform_data = &hw_if;
synaptics_dsx_i2c_device->dev.release = synaptics_rmi4_i2c_dev_release;
retval = platform_device_register(synaptics_dsx_i2c_device);
if (retval) {
dev_err(&client->dev,
"%s: Failed to register platform device\n",
__func__);
ret = -ENODEV;
goto error;
}
#ifdef CUST_LGE_TOUCH_BRING_UP
printk("[Touch D] Complete %s !!! \n",__func__);
#endif
return 0;
#ifdef CUST_LGE_TOUCH_BRING_UP
error:
devm_kfree(&client->dev, p_data);
#endif
That last part is where the compiler warning is, can it because error: is after return 0; ?
#ifdef CUST_LGE_TOUCH_BRING_UP
error:
devm_kfree(&client->dev, p_data);
#endif
If client->dev.of_node is false here
if (client->dev.of_node) {
p_data is never initialised, but still the code finally calls
devm_kfree(&client->dev, p_data);
hence the warning.
To fix this you might want to change this
struct synaptics_dsx_board_data *p_data;
to be
struct synaptics_dsx_board_data *p_data = NULL;
This fix assumes that devm_kfree(&client->dev, p_data); can handle a NULL being past as last argument.