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@@ -255,150 +255,140 @@ static int spi_bitbang_bufs(struct spi_device *spi, struct spi_transfer *t)
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* Drivers can provide word-at-a-time i/o primitives, or provide
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* transfer-at-a-time ones to leverage dma or fifo hardware.
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*/
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-static void bitbang_work(struct work_struct *work)
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+
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+static int spi_bitbang_prepare_hardware(struct spi_master *spi)
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{
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- struct spi_bitbang *bitbang =
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- container_of(work, struct spi_bitbang, work);
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+ struct spi_bitbang *bitbang;
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unsigned long flags;
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- struct spi_message *m, *_m;
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+
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+ bitbang = spi_master_get_devdata(spi);
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spin_lock_irqsave(&bitbang->lock, flags);
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bitbang->busy = 1;
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- list_for_each_entry_safe(m, _m, &bitbang->queue, queue) {
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- struct spi_device *spi;
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- unsigned nsecs;
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- struct spi_transfer *t = NULL;
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- unsigned tmp;
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- unsigned cs_change;
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- int status;
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- int do_setup = -1;
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-
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- list_del(&m->queue);
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- spin_unlock_irqrestore(&bitbang->lock, flags);
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-
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- /* FIXME this is made-up ... the correct value is known to
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- * word-at-a-time bitbang code, and presumably chipselect()
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- * should enforce these requirements too?
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- */
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- nsecs = 100;
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+ spin_unlock_irqrestore(&bitbang->lock, flags);
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- spi = m->spi;
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- tmp = 0;
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- cs_change = 1;
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- status = 0;
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+ return 0;
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+}
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- list_for_each_entry (t, &m->transfers, transfer_list) {
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-
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- /* override speed or wordsize? */
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- if (t->speed_hz || t->bits_per_word)
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- do_setup = 1;
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-
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- /* init (-1) or override (1) transfer params */
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- if (do_setup != 0) {
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- status = bitbang->setup_transfer(spi, t);
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- if (status < 0)
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- break;
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- if (do_setup == -1)
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- do_setup = 0;
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- }
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-
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- /* set up default clock polarity, and activate chip;
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- * this implicitly updates clock and spi modes as
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- * previously recorded for this device via setup().
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- * (and also deselects any other chip that might be
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- * selected ...)
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- */
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- if (cs_change) {
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- bitbang->chipselect(spi, BITBANG_CS_ACTIVE);
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- ndelay(nsecs);
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- }
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- cs_change = t->cs_change;
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- if (!t->tx_buf && !t->rx_buf && t->len) {
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- status = -EINVAL;
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- break;
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- }
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+static int spi_bitbang_transfer_one(struct spi_master *master,
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+ struct spi_message *m)
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+{
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+ struct spi_bitbang *bitbang;
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+ unsigned nsecs;
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+ struct spi_transfer *t = NULL;
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+ unsigned cs_change;
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+ int status;
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+ int do_setup = -1;
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+ struct spi_device *spi = m->spi;
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+
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+ bitbang = spi_master_get_devdata(master);
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+
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+ /* FIXME this is made-up ... the correct value is known to
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+ * word-at-a-time bitbang code, and presumably chipselect()
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+ * should enforce these requirements too?
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+ */
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+ nsecs = 100;
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- /* transfer data. the lower level code handles any
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- * new dma mappings it needs. our caller always gave
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- * us dma-safe buffers.
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- */
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- if (t->len) {
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- /* REVISIT dma API still needs a designated
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- * DMA_ADDR_INVALID; ~0 might be better.
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- */
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- if (!m->is_dma_mapped)
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- t->rx_dma = t->tx_dma = 0;
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- status = bitbang->txrx_bufs(spi, t);
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- }
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- if (status > 0)
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- m->actual_length += status;
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- if (status != t->len) {
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- /* always report some kind of error */
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- if (status >= 0)
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- status = -EREMOTEIO;
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+ cs_change = 1;
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+ status = 0;
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+
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+ list_for_each_entry (t, &m->transfers, transfer_list) {
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+
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+ /* override speed or wordsize? */
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+ if (t->speed_hz || t->bits_per_word)
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+ do_setup = 1;
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+
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+ /* init (-1) or override (1) transfer params */
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+ if (do_setup != 0) {
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+ status = bitbang->setup_transfer(spi, t);
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+ if (status < 0)
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break;
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- }
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- status = 0;
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-
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- /* protocol tweaks before next transfer */
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- if (t->delay_usecs)
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- udelay(t->delay_usecs);
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-
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- if (cs_change && !list_is_last(&t->transfer_list, &m->transfers)) {
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- /* sometimes a short mid-message deselect of the chip
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- * may be needed to terminate a mode or command
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- */
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- ndelay(nsecs);
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- bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
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- ndelay(nsecs);
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- }
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+ if (do_setup == -1)
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+ do_setup = 0;
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}
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- m->status = status;
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- m->complete(m->context);
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+ /* set up default clock polarity, and activate chip;
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+ * this implicitly updates clock and spi modes as
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+ * previously recorded for this device via setup().
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+ * (and also deselects any other chip that might be
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+ * selected ...)
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+ */
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+ if (cs_change) {
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+ bitbang->chipselect(spi, BITBANG_CS_ACTIVE);
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+ ndelay(nsecs);
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+ }
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+ cs_change = t->cs_change;
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+ if (!t->tx_buf && !t->rx_buf && t->len) {
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+ status = -EINVAL;
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+ break;
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+ }
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- /* normally deactivate chipselect ... unless no error and
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- * cs_change has hinted that the next message will probably
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- * be for this chip too.
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+ /* transfer data. the lower level code handles any
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+ * new dma mappings it needs. our caller always gave
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+ * us dma-safe buffers.
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*/
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- if (!(status == 0 && cs_change)) {
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+ if (t->len) {
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+ /* REVISIT dma API still needs a designated
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+ * DMA_ADDR_INVALID; ~0 might be better.
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+ */
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+ if (!m->is_dma_mapped)
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+ t->rx_dma = t->tx_dma = 0;
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+ status = bitbang->txrx_bufs(spi, t);
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+ }
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+ if (status > 0)
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+ m->actual_length += status;
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+ if (status != t->len) {
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+ /* always report some kind of error */
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+ if (status >= 0)
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+ status = -EREMOTEIO;
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+ break;
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+ }
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+ status = 0;
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+
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+ /* protocol tweaks before next transfer */
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+ if (t->delay_usecs)
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+ udelay(t->delay_usecs);
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+
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+ if (cs_change && !list_is_last(&t->transfer_list, &m->transfers)) {
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+ /* sometimes a short mid-message deselect of the chip
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+ * may be needed to terminate a mode or command
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+ */
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ndelay(nsecs);
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bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
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ndelay(nsecs);
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}
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+ }
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+
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+ m->status = status;
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- spin_lock_irqsave(&bitbang->lock, flags);
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+ /* normally deactivate chipselect ... unless no error and
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+ * cs_change has hinted that the next message will probably
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+ * be for this chip too.
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+ */
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+ if (!(status == 0 && cs_change)) {
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+ ndelay(nsecs);
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+ bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
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+ ndelay(nsecs);
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}
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- bitbang->busy = 0;
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- spin_unlock_irqrestore(&bitbang->lock, flags);
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+
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+ spi_finalize_current_message(master);
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+
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+ return status;
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}
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-/**
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- * spi_bitbang_transfer - default submit to transfer queue
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- */
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-int spi_bitbang_transfer(struct spi_device *spi, struct spi_message *m)
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+static int spi_bitbang_unprepare_hardware(struct spi_master *spi)
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{
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- struct spi_bitbang *bitbang;
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+ struct spi_bitbang *bitbang;
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unsigned long flags;
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- int status = 0;
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- m->actual_length = 0;
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- m->status = -EINPROGRESS;
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-
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- bitbang = spi_master_get_devdata(spi->master);
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+ bitbang = spi_master_get_devdata(spi);
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spin_lock_irqsave(&bitbang->lock, flags);
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- if (!spi->max_speed_hz)
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- status = -ENETDOWN;
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- else {
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- list_add_tail(&m->queue, &bitbang->queue);
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- queue_work(bitbang->workqueue, &bitbang->work);
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- }
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+ bitbang->busy = 0;
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spin_unlock_irqrestore(&bitbang->lock, flags);
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- return status;
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+ return 0;
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}
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-EXPORT_SYMBOL_GPL(spi_bitbang_transfer);
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/*----------------------------------------------------------------------*/
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@@ -428,20 +418,22 @@ EXPORT_SYMBOL_GPL(spi_bitbang_transfer);
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int spi_bitbang_start(struct spi_bitbang *bitbang)
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{
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struct spi_master *master = bitbang->master;
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- int status;
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if (!master || !bitbang->chipselect)
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return -EINVAL;
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- INIT_WORK(&bitbang->work, bitbang_work);
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spin_lock_init(&bitbang->lock);
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- INIT_LIST_HEAD(&bitbang->queue);
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if (!master->mode_bits)
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master->mode_bits = SPI_CPOL | SPI_CPHA | bitbang->flags;
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- if (!master->transfer)
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- master->transfer = spi_bitbang_transfer;
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+ if (master->transfer || master->transfer_one_message)
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+ return -EINVAL;
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+
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+ master->prepare_transfer_hardware = spi_bitbang_prepare_hardware;
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+ master->unprepare_transfer_hardware = spi_bitbang_unprepare_hardware;
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+ master->transfer_one_message = spi_bitbang_transfer_one;
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+
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if (!bitbang->txrx_bufs) {
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bitbang->use_dma = 0;
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bitbang->txrx_bufs = spi_bitbang_bufs;
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@@ -452,34 +444,12 @@ int spi_bitbang_start(struct spi_bitbang *bitbang)
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master->setup = spi_bitbang_setup;
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master->cleanup = spi_bitbang_cleanup;
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}
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- } else if (!master->setup)
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- return -EINVAL;
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- if (master->transfer == spi_bitbang_transfer &&
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- !bitbang->setup_transfer)
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- return -EINVAL;
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-
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- /* this task is the only thing to touch the SPI bits */
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- bitbang->busy = 0;
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- bitbang->workqueue = create_singlethread_workqueue(
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- dev_name(master->dev.parent));
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- if (bitbang->workqueue == NULL) {
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- status = -EBUSY;
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- goto err1;
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}
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/* driver may get busy before register() returns, especially
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* if someone registered boardinfo for devices
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*/
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- status = spi_register_master(master);
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- if (status < 0)
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- goto err2;
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-
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- return status;
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-
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-err2:
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- destroy_workqueue(bitbang->workqueue);
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-err1:
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- return status;
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+ return spi_register_master(master);
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}
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EXPORT_SYMBOL_GPL(spi_bitbang_start);
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@@ -490,10 +460,6 @@ int spi_bitbang_stop(struct spi_bitbang *bitbang)
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{
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spi_unregister_master(bitbang->master);
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- WARN_ON(!list_empty(&bitbang->queue));
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-
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- destroy_workqueue(bitbang->workqueue);
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-
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return 0;
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}
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EXPORT_SYMBOL_GPL(spi_bitbang_stop);
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