To generate the patch for the given code slice with a CWE-401 (Improper Release of Memory Before Removing Last Reference) vulnerability, we can follow these reasoning steps:

### Step 1: Root Cause Analysis

- 1: Identify the Resource:
  - The resource in question is the memory allocated for `struct ds2760_device_info *di`.
  - This memory is obtained through `platform_get_drvdata(pdev)`.

- 2: Memory Management:
  - The function `ds2760_battery_remove` appears to be a removal function, likely called when the device is being removed or unloaded.
  - The function performs various cleanup tasks, such as canceling delayed work and unregistering a power supply.

- 3: Potential Vulnerability:
  - The vulnerability arises because the function does not release the memory allocated for `di` before returning.
  - This is a memory leak, as the memory is not freed, and there is no indication that it will be freed elsewhere.

### Conclusion:
The vulnerable behavior in this code is a memory leak. It occurs because the function does not properly release the memory allocated for `struct ds2760_device_info *di` before returning. This can lead to memory exhaustion over time, especially if the function is called repeatedly.

### Step 2: Fixing Strategy

- A common fixing strategy for memory leaks is to ensure that all allocated memory is properly freed when it is no longer needed.
- In this case, we need to add a call to `kfree(di)` to free the memory allocated for `di`.
- The `kfree` function is used to free kernel memory, and it should be called after the last use of the memory.

- The patch should be:
```
<     power_supply_unregister(&di->bat);
<     return 0;
---
>     power_supply_unregister(&di->bat);
>     kfree(di);
>     return 0;
```
This patch ensures that the memory allocated for `di` is properly freed before the function returns, preventing a memory leak.