+static int mpc83xx_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
+{
+ struct mpc83xx_spi *mpc83xx_spi;
+ u32 word, len, bits_per_word;
+
+ mpc83xx_spi = spi_master_get_devdata(spi->master);
+
+ mpc83xx_spi->tx = t->tx_buf;
+ mpc83xx_spi->rx = t->rx_buf;
+ bits_per_word = spi->bits_per_word;
+ if (t->bits_per_word)
+ bits_per_word = t->bits_per_word;
+ len = t->len;
+ if (bits_per_word > 8)
+ len /= 2;
+ if (bits_per_word > 16)
+ len /= 2;
+ mpc83xx_spi->count = len;
+ INIT_COMPLETION(mpc83xx_spi->done);
+
+ /* enable rx ints */
+ mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, SPIM_NE);
+
+ /* transmit word */
+ word = mpc83xx_spi->get_tx(mpc83xx_spi);
+ mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit, word);
+
+ wait_for_completion(&mpc83xx_spi->done);
+
+ /* disable rx ints */
+ mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0);
+
+ return mpc83xx_spi->count;
+}
+
+static void mpc83xx_spi_work(struct work_struct *work)
+{
+ struct mpc83xx_spi *mpc83xx_spi =
+ container_of(work, struct mpc83xx_spi, work);
+
+ spin_lock_irq(&mpc83xx_spi->lock);
+ mpc83xx_spi->busy = 1;
+ while (!list_empty(&mpc83xx_spi->queue)) {
+ struct spi_message *m;
+ struct spi_device *spi;
+ struct spi_transfer *t = NULL;
+ unsigned cs_change;
+ int status, nsecs = 50;
+
+ m = container_of(mpc83xx_spi->queue.next,
+ struct spi_message, queue);
+ list_del_init(&m->queue);
+ spin_unlock_irq(&mpc83xx_spi->lock);
+
+ spi = m->spi;
+ cs_change = 1;
+ status = 0;
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ if (t->bits_per_word || t->speed_hz) {
+ /* Don't allow changes if CS is active */
+ status = -EINVAL;
+
+ if (cs_change)
+ status = mpc83xx_spi_setup_transfer(spi, t);
+ if (status < 0)
+ break;
+ }
+
+ if (cs_change)
+ mpc83xx_spi_chipselect(spi, BITBANG_CS_ACTIVE);
+ cs_change = t->cs_change;
+ if (t->len)
+ status = mpc83xx_spi_bufs(spi, t);
+ if (status) {
+ status = -EMSGSIZE;
+ break;
+ }
+ m->actual_length += t->len;
+
+ if (t->delay_usecs)
+ udelay(t->delay_usecs);
+
+ if (cs_change) {
+ ndelay(nsecs);
+ mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+ ndelay(nsecs);
+ }
+ }
+
+ m->status = status;
+ m->complete(m->context);
+
+ if (status || !cs_change) {
+ ndelay(nsecs);
+ mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+ }
+
+ mpc83xx_spi_setup_transfer(spi, NULL);
+
+ spin_lock_irq(&mpc83xx_spi->lock);
+ }
+ mpc83xx_spi->busy = 0;
+ spin_unlock_irq(&mpc83xx_spi->lock);
+}
+