On 6/19/22 6:43 AM, Andy Shevchenko wrote:
> On Sat, Jun 18, 2022 at 7:10 PM Samuel Holland <samuel@xxxxxxxxxxxx> wrote:
>>
>> The official Pine64 PinePhone keyboard case contains a matrix keypad and
>> a MCU which runs a libre firmware. Add support for its I2C interface.
>
> ...
>
>> +#include <linux/crc8.h>
>> +#include <linux/i2c.h>
>> +#include <linux/input/matrix_keypad.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/module.h>
>> +#include <linux/regulator/consumer.h>
>
> Missed
> types.h
>
> ...
>
>> +#define PPKB_ROWS 6
>> +#define PPKB_COLS 12
>
> ...
>
>> + for (col = 0; col < PPKB_COLS; ++col) {
>> + u8 old = old_buf[1 + col];
>> + u8 new = new_buf[1 + col];
>> + u8 changed = old ^ new;
>> +
>> + if (!changed)
>> + continue;
>> +
>> + for (row = 0; row < PPKB_ROWS; ++row) {
>> + u8 mask = BIT(row);
>> + u8 value = new & mask;
>> + unsigned short code;
>> + bool fn_state;
>> +
>> + if (!(changed & mask))
>> + continue;
>> +
>> + /*
>> + * Save off the FN key state when the key was pressed,
>> + * and use that to determine the code during a release.
>> + */
>> + fn_state = value ? ppkb->fn_pressed : ppkb->fn_state[col] & mask;
>> + if (fn_state)
>> + ppkb->fn_state[col] ^= mask;
>
> Can't it be converted to use bitmap APIs?
This is a 2D matrix, with one byte per column, and one bit per row. There are
only 6 rows, so two bits per byte are unused. Converting this to the bitmap API
would unnecessarily complicate things.
>> + }
>> + }
>
> ...
>
>> +static int ppkb_set_scan(struct i2c_client *client, bool enable)
>> +{
>> + struct device *dev = &client->dev;
>> + int ret, val;
>> +
>> + ret = i2c_smbus_read_byte_data(client, PPKB_SYS_CONFIG);
>> + if (ret < 0) {
>> + dev_err(dev, "Failed to read config: %d\n", ret);
>> + return ret;
>> + }
>> +
>> + if (enable)
>> + val = ret & ~PPKB_SYS_CONFIG_DISABLE_SCAN;
>> + else
>> + val = ret | PPKB_SYS_CONFIG_DISABLE_SCAN;
>> + ret = i2c_smbus_write_byte_data(client, PPKB_SYS_CONFIG, val);
>> + if (ret) {
>> + dev_err(dev, "Failed to write config: %d\n", ret);
>
>> + return ret;
>> + }
>> +
>> + return 0;
>
> return ret;
The "return 0" pattern is idiomatic, and more diff-friendly when adding error
handling or more operations. But I don't have that strong of an opinion on it.
Regards,
Samuel
