Re: [RFC] spi: Using Trigger number to transmit/receive data

[カオ ミン ヒェップ <cm-hiep@jinso.co.jp>]

Hi Morimoto

On 03/13/2014 06:27 PM, Kuninori Morimoto wrote:
> Hi Hiep
>
>> In order to transmit and receive data when have 32 bytes of data that
>> ready has prepared on Transmit/Receive Buffer to transmit or receive.
>> Instead transmits/receives a byte data using Transmit/Receive Buffer
>> Data Triggering Number will improve the speed of transfer data.
>>
>> Signed-off-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
>> ---
> (snip)
>> +static int qspi_set_send_trigger(struct rspi_data *rspi, int remain)
>> +{
>> +	int n;
>> +
>> +	n = min(remain, QSPI_BUFFER_SIZE);
>> +
>> +	if (remain >= QSPI_BUFFER_SIZE) {
>> +		/* sets triggering number to 32 bytes */
>> +		qspi_update(rspi, SPBFCR_TXTRG_MASK,
>> +			     SPBFCR_TXTRG_0B, QSPI_SPBFCR);
>> +	} else {
>> +		/* sets triggering number to 1 byte */
>> +		qspi_update(rspi, SPBFCR_TXTRG_MASK,
>> +			     SPBFCR_TXTRG_31B, QSPI_SPBFCR);
>> +	}
>> +
>> +	return n;
>> +}
> (snip)
>> +		n = qspi_set_send_trigger(rspi, remain);
>> +		if (n >= QSPI_BUFFER_SIZE) {
>> +			for (i = 0; i < n; i++)
>> +				rspi_write8(rspi, *data++, RSPI_SPDR);
>> +			if (rspi_wait_for_interrupt(rspi, SPSR_SPRF,
>> +						    SPCR_SPRIE) < 0) {
>> +				dev_err(&rspi->master->dev,
>> +					"%s: receive timeout\n", __func__);
>> +				return -ETIMEDOUT;
>> +			}
>> +			for (i = 0; i < n; i++)
>> +				rspi_read8(rspi, RSPI_SPDR);
>> +		} else {
>> +			for (i = 0; i < n; i++) {
>> +				if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF,
>> +							    SPCR_SPTIE) < 0) {
>> +					dev_err(&rspi->master->dev,
>> +					   "%s: tx empty timeout\n", __func__);
>> +				return -ETIMEDOUT;
>> +				}
>> +				rspi_write8(rspi, *data++, RSPI_SPDR);
>> +
>> +				if (rspi_wait_for_interrupt(rspi, SPSR_SPRF,
>> +							    SPCR_SPRIE) < 0) {
>> +					dev_err(&rspi->master->dev,
>> +					   "%s: receive timeout\n", __func__);
>> +				return -ETIMEDOUT;
>> +				}
>> +				rspi_read8(rspi, RSPI_SPDR);
>> +			}
> I guess, this "qspi_set_send_trigger()" is mode "settings",
> and, "transfer" is done here.
>
> I think "setting" and "tranfer" in 1 function is readable.
>
Thanks for your comments, I will do so.