static bool ht16k33_keypad_scan()

in ht16k33.c [372:407]

• 32 lines of code
• 4 McCabe index (conditional complexity)

static bool ht16k33_keypad_scan(struct ht16k33_keypad *keypad)
{
	const unsigned short *keycodes = keypad->dev->keycode;
	u16 new_state[HT16K33_MATRIX_KEYPAD_MAX_COLS];
	__le16 data[HT16K33_MATRIX_KEYPAD_MAX_COLS];
	unsigned long bits_changed;
	int row, col, code;
	int rc;
	bool pressed = false;

	rc = i2c_smbus_read_i2c_block_data(keypad->client, 0x40,
					   sizeof(data), (u8 *)data);
	if (rc != sizeof(data)) {
		dev_err(&keypad->client->dev,
			"Failed to read key data, rc=%d\n", rc);
		return false;
	}

	for (col = 0; col < keypad->cols; col++) {
		new_state[col] = le16_to_cpu(data[col]);
		if (new_state[col])
			pressed = true;
		bits_changed = keypad->last_key_state[col] ^ new_state[col];

		for_each_set_bit(row, &bits_changed, BITS_PER_LONG) {
			code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
			input_event(keypad->dev, EV_MSC, MSC_SCAN, code);
			input_report_key(keypad->dev, keycodes[code],
					 new_state[col] & BIT(row));
		}
	}
	input_sync(keypad->dev);
	memcpy(keypad->last_key_state, new_state, sizeof(u16) * keypad->cols);

	return pressed;
}