[PATCH v5 3/4] drivers/i2c/busses/i2c-at91.c: add new driver
Voss, Nikolaus
N.Voss at weinmann.de
Tue Nov 22 11:26:18 EST 2011
Hi,
Carsten Behling wrote on 2011-11-22:
> +static void at91_twi_read_next_byte(struct at91_twi_dev *dev)
> +{
> + *dev->buf = at91_twi_read(dev, AT91_TWI_RHR) & 0xff;
> +
> + /* send stop if second but last byte has been read */
> + if (--dev->buf_len == 1)
> + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_STOP);
>
>
>
> If dev->buf_len =1 at the beginning of a read transfer, a stop condition will
> never be send.
this case is already catched in at91_do_twi_transfer():
+ if (dev->msg->flags & I2C_M_RD) {
+ unsigned start_flags = AT91_TWI_START;
+
+ /* if only one byte is to be read, immediately stop transfer */
+ if (dev->buf_len <= 1 && !(dev->msg->flags & I2C_M_RECV_LEN))
+ start_flags |= AT91_TWI_STOP;
+ at91_twi_write(dev, AT91_TWI_CR, start_flags);
Thanks for reviewing,
Niko
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