Re: [PATCH V14 3/5] i2c: tegra: Add DMA support

[Dmitry Osipenko]

07.02.2019 22:14, Dmitry Osipenko ÐÐÑÐÑ:
> 06.02.2019 22:16, Sowjanya Komatineni ÐÐÑÐÑ:
>> +static void tegra_i2c_config_fifo_trig(struct tegra_i2c_dev *i2c_dev,
>> +				       size_t len)
>> +{
>> +	u32 val = 0, reg;
>> +	u8 dma_burst = 0;

There is no need to set dma_burst to zero as well. In general you only need to initialize variables if code uses the uninitialized variable.

>> +	struct dma_slave_config slv_config = {0};
>> +	struct dma_chan *chan;
>> +	int ret;
>> +	unsigned long reg_offset;
>> +
>> +	if (i2c_dev->hw->has_mst_fifo)
>> +		reg = I2C_MST_FIFO_CONTROL;
>> +	else
>> +		reg = I2C_FIFO_CONTROL;
>> +
>> +	if (i2c_dev->is_curr_dma_xfer) {
>> +		if (len & 0xF)
>> +			dma_burst = 1;
>> +		else if (len & 0x10)
>> +			dma_burst = 4;
>> +		else
>> +			dma_burst = 8;

In this case compiler just ignores the first initialization because it is explicitly initialized later on in the code path that actually uses the dma_burst variable. Avoiding unnecessary initialization helps to keep code a bit more clean.