[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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