at86rf230: add recommended csma backoffs settings

This patch adds support for a new random csma backoffs settings when
going into sleep state. This is recommended according at86rf2xx
datasheets.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Alexander Aring 2015-06-16 11:07:43 +02:00 committed by Marcel Holtmann
parent cbe6234689
commit 74ed9d9845
1 changed files with 11 additions and 0 deletions

View File

@ -945,10 +945,21 @@ static void
at86rf230_stop(struct ieee802154_hw *hw)
{
struct at86rf230_local *lp = hw->priv;
u8 csma_seed[2];
at86rf230_sync_state_change(hw->priv, STATE_FORCE_TRX_OFF);
disable_irq(lp->spi->irq);
/* It's recommended to set random new csma_seeds before sleep state.
* Makes only sense in the stop callback, not doing this inside of
* at86rf230_sleep, this is also used when we don't transmit afterwards
* when calling start callback again.
*/
get_random_bytes(csma_seed, ARRAY_SIZE(csma_seed));
at86rf230_write_subreg(lp, SR_CSMA_SEED_0, csma_seed[0]);
at86rf230_write_subreg(lp, SR_CSMA_SEED_1, csma_seed[1]);
at86rf230_sleep(lp);
}