Merge remote-tracking branch 'spi/topic/bitbang' into spi-next

5 files changed, 113 insertions, 193 deletions

diff --git a/drivers/spi/spi-altera.c b/drivers/spi/spi-altera.c
index 523f2f649e26..156eb888655e 100644
--- a/drivers/spi/spi-altera.c
+++ b/drivers/spi/spi-altera.c
@@ -103,16 +103,6 @@ static void altera_spi_chipsel(struct spi_device *spi, int value)
         }
 }
 
-static int altera_spi_setupxfer(struct spi_device *spi, struct spi_transfer *t)
-{
-        return 0;
-}
-
-static int altera_spi_setup(struct spi_device *spi)
-{
-        return 0;
-}
-
 static inline unsigned int hw_txbyte(struct altera_spi *hw, int count)
 {
         if (hw->tx) {
@@ -224,7 +214,6 @@ static int altera_spi_probe(struct platform_device *pdev)
         master->bus_num = pdev->id;
         master->num_chipselect = 16;
         master->mode_bits = SPI_CS_HIGH;
-        master->setup = altera_spi_setup;
 
         hw = spi_master_get_devdata(master);
         platform_set_drvdata(pdev, hw);
@@ -233,7 +222,6 @@ static int altera_spi_probe(struct platform_device *pdev)
         hw->bitbang.master = spi_master_get(master);
         if (!hw->bitbang.master)
                 return err;
-        hw->bitbang.setup_transfer = altera_spi_setupxfer;
         hw->bitbang.chipselect = altera_spi_chipsel;
         hw->bitbang.txrx_bufs = altera_spi_txrx;
 
diff --git a/drivers/spi/spi-bitbang.c b/drivers/spi/spi-bitbang.c
index a63d7da3bfe2..e3946e44e076 100644
--- a/drivers/spi/spi-bitbang.c
+++ b/drivers/spi/spi-bitbang.c
@@ -255,150 +255,140 @@ static int spi_bitbang_bufs(struct spi_device *spi, struct spi_transfer *t)
  * Drivers can provide word-at-a-time i/o primitives, or provide
  * transfer-at-a-time ones to leverage dma or fifo hardware.
  */
-static void bitbang_work(struct work_struct *work)
+
+static int spi_bitbang_prepare_hardware(struct spi_master *spi)
 {
-        struct spi_bitbang      *bitbang =
-                container_of(work, struct spi_bitbang, work);
+        struct spi_bitbang      *bitbang;
         unsigned long           flags;
-        struct spi_message      *m, *_m;
+
+        bitbang = spi_master_get_devdata(spi);
 
         spin_lock_irqsave(&bitbang->lock, flags);
         bitbang->busy = 1;
-        list_for_each_entry_safe(m, _m, &bitbang->queue, queue) {
-                struct spi_device       *spi;
-                unsigned                nsecs;
-                struct spi_transfer     *t = NULL;
-                unsigned                tmp;
-                unsigned                cs_change;
-                int                     status;
-                int                     do_setup = -1;
-
-                list_del(&m->queue);
-                spin_unlock_irqrestore(&bitbang->lock, flags);
-
-                /* FIXME this is made-up ... the correct value is known to
-                 * word-at-a-time bitbang code, and presumably chipselect()
-                 * should enforce these requirements too?
-                 */
-                nsecs = 100;
+        spin_unlock_irqrestore(&bitbang->lock, flags);
 
-                spi = m->spi;
-                tmp = 0;
-                cs_change = 1;
-                status = 0;
+        return 0;
+}
 
-                list_for_each_entry (t, &m->transfers, transfer_list) {
-
-                        /* override speed or wordsize? */
-                        if (t->speed_hz || t->bits_per_word)
-                                do_setup = 1;
-
-                        /* init (-1) or override (1) transfer params */
-                        if (do_setup != 0) {
-                                status = bitbang->setup_transfer(spi, t);
-                                if (status < 0)
-                                        break;
-                                if (do_setup == -1)
-                                        do_setup = 0;
-                        }
-
-                        /* set up default clock polarity, and activate chip;
-                         * this implicitly updates clock and spi modes as
-                         * previously recorded for this device via setup().
-                         * (and also deselects any other chip that might be
-                         * selected ...)
-                         */
-                        if (cs_change) {
-                                bitbang->chipselect(spi, BITBANG_CS_ACTIVE);
-                                ndelay(nsecs);
-                        }
-                        cs_change = t->cs_change;
-                        if (!t->tx_buf && !t->rx_buf && t->len) {
-                                status = -EINVAL;
-                                break;
-                        }
+static int spi_bitbang_transfer_one(struct spi_master *master,
+                                    struct spi_message *m)
+{
+        struct spi_bitbang      *bitbang;
+        unsigned                nsecs;
+        struct spi_transfer     *t = NULL;
+        unsigned                cs_change;
+        int                     status;
+        int                     do_setup = -1;
+        struct spi_device       *spi = m->spi;
+
+        bitbang = spi_master_get_devdata(master);
+
+        /* FIXME this is made-up ... the correct value is known to
+         * word-at-a-time bitbang code, and presumably chipselect()
+         * should enforce these requirements too?
+         */
+        nsecs = 100;
 
-                        /* transfer data.  the lower level code handles any
-                         * new dma mappings it needs. our caller always gave
-                         * us dma-safe buffers.
-                         */
-                        if (t->len) {
-                                /* REVISIT dma API still needs a designated
-                                 * DMA_ADDR_INVALID; ~0 might be better.
-                                 */
-                                if (!m->is_dma_mapped)
-                                        t->rx_dma = t->tx_dma = 0;
-                                status = bitbang->txrx_bufs(spi, t);
-                        }
-                        if (status > 0)
-                                m->actual_length += status;
-                        if (status != t->len) {
-                                /* always report some kind of error */
-                                if (status >= 0)
-                                        status = -EREMOTEIO;
+        cs_change = 1;
+        status = 0;
+
+        list_for_each_entry (t, &m->transfers, transfer_list) {
+
+                /* override speed or wordsize? */
+                if (t->speed_hz || t->bits_per_word)
+                        do_setup = 1;
+
+                /* init (-1) or override (1) transfer params */
+                if (do_setup != 0) {
+                        status = bitbang->setup_transfer(spi, t);
+                        if (status < 0)
                                 break;
-                        }
-                        status = 0;
-
-                        /* protocol tweaks before next transfer */
-                        if (t->delay_usecs)
-                                udelay(t->delay_usecs);
-
-                        if (cs_change && !list_is_last(&t->transfer_list, &m->transfers)) {
-                                /* sometimes a short mid-message deselect of the chip
-                                 * may be needed to terminate a mode or command
-                                 */
-                                ndelay(nsecs);
-                                bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
-                                ndelay(nsecs);
-                        }
+                        if (do_setup == -1)
+                                do_setup = 0;
                 }
 
-                m->status = status;
-                m->complete(m->context);
+                /* set up default clock polarity, and activate chip;
+                 * this implicitly updates clock and spi modes as
+                 * previously recorded for this device via setup().
+                 * (and also deselects any other chip that might be
+                 * selected ...)
+                 */
+                if (cs_change) {
+                        bitbang->chipselect(spi, BITBANG_CS_ACTIVE);
+                        ndelay(nsecs);
+                }
+                cs_change = t->cs_change;
+                if (!t->tx_buf && !t->rx_buf && t->len) {
+                        status = -EINVAL;
+                        break;
+                }
 
-                /* normally deactivate chipselect ... unless no error and
-                 * cs_change has hinted that the next message will probably
-                 * be for this chip too.
+                /* transfer data.  the lower level code handles any
+                 * new dma mappings it needs. our caller always gave
+                 * us dma-safe buffers.
                  */
-                if (!(status == 0 && cs_change)) {
+                if (t->len) {
+                        /* REVISIT dma API still needs a designated
+                         * DMA_ADDR_INVALID; ~0 might be better.
+                         */
+                        if (!m->is_dma_mapped)
+                                t->rx_dma = t->tx_dma = 0;
+                        status = bitbang->txrx_bufs(spi, t);
+                }
+                if (status > 0)
+                        m->actual_length += status;
+                if (status != t->len) {
+                        /* always report some kind of error */
+                        if (status >= 0)
+                                status = -EREMOTEIO;
+                        break;
+                }
+                status = 0;
+
+                /* protocol tweaks before next transfer */
+                if (t->delay_usecs)
+                        udelay(t->delay_usecs);
+
+                if (cs_change && !list_is_last(&t->transfer_list, &m->transfers)) {
+                        /* sometimes a short mid-message deselect of the chip
+                         * may be needed to terminate a mode or command
+                         */
                         ndelay(nsecs);
                         bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
                         ndelay(nsecs);
                 }
+        }
+
+        m->status = status;
 
-                spin_lock_irqsave(&bitbang->lock, flags);
+        /* normally deactivate chipselect ... unless no error and
+         * cs_change has hinted that the next message will probably
+         * be for this chip too.
+         */
+        if (!(status == 0 && cs_change)) {
+                ndelay(nsecs);
+                bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
+                ndelay(nsecs);
         }
-        bitbang->busy = 0;
-        spin_unlock_irqrestore(&bitbang->lock, flags);
+
+        spi_finalize_current_message(master);
+
+        return status;
 }
 
-/**
- * spi_bitbang_transfer - default submit to transfer queue
- */
-int spi_bitbang_transfer(struct spi_device *spi, struct spi_message *m)
+static int spi_bitbang_unprepare_hardware(struct spi_master *spi)
 {
-        struct spi_bitbang      *bitbang;
+        struct spi_bitbang      *bitbang;
         unsigned long           flags;
-        int                     status = 0;
 
-        m->actual_length = 0;
-        m->status = -EINPROGRESS;
-
-        bitbang = spi_master_get_devdata(spi->master);
+        bitbang = spi_master_get_devdata(spi);
 
         spin_lock_irqsave(&bitbang->lock, flags);
-        if (!spi->max_speed_hz)
-                status = -ENETDOWN;
-        else {
-                list_add_tail(&m->queue, &bitbang->queue);
-                queue_work(bitbang->workqueue, &bitbang->work);
-        }
+        bitbang->busy = 0;
         spin_unlock_irqrestore(&bitbang->lock, flags);
 
-        return status;
+        return 0;
 }
-EXPORT_SYMBOL_GPL(spi_bitbang_transfer);
 
 /*----------------------------------------------------------------------*/
 
@@ -428,20 +418,22 @@ EXPORT_SYMBOL_GPL(spi_bitbang_transfer);
 int spi_bitbang_start(struct spi_bitbang *bitbang)
 {
         struct spi_master *master = bitbang->master;
-        int status;
 
         if (!master || !bitbang->chipselect)
                 return -EINVAL;
 
-        INIT_WORK(&bitbang->work, bitbang_work);
         spin_lock_init(&bitbang->lock);
-        INIT_LIST_HEAD(&bitbang->queue);
 
         if (!master->mode_bits)
                 master->mode_bits = SPI_CPOL | SPI_CPHA | bitbang->flags;
 
-        if (!master->transfer)
-                master->transfer = spi_bitbang_transfer;
+        if (master->transfer || master->transfer_one_message)
+                return -EINVAL;
+
+        master->prepare_transfer_hardware = spi_bitbang_prepare_hardware;
+        master->unprepare_transfer_hardware = spi_bitbang_unprepare_hardware;
+        master->transfer_one_message = spi_bitbang_transfer_one;
+
         if (!bitbang->txrx_bufs) {
                 bitbang->use_dma = 0;
                 bitbang->txrx_bufs = spi_bitbang_bufs;
@@ -452,34 +444,12 @@ int spi_bitbang_start(struct spi_bitbang *bitbang)
                         master->setup = spi_bitbang_setup;
                         master->cleanup = spi_bitbang_cleanup;
                 }
-        } else if (!master->setup)
-                return -EINVAL;
-        if (master->transfer == spi_bitbang_transfer &&
-                        !bitbang->setup_transfer)
-                return -EINVAL;
-
-        /* this task is the only thing to touch the SPI bits */
-        bitbang->busy = 0;
-        bitbang->workqueue = create_singlethread_workqueue(
-                        dev_name(master->dev.parent));
-        if (bitbang->workqueue == NULL) {
-                status = -EBUSY;
-                goto err1;
         }
 
         /* driver may get busy before register() returns, especially
          * if someone registered boardinfo for devices
          */
-        status = spi_register_master(master);
-        if (status < 0)
-                goto err2;
-
-        return status;
-
-err2:
-        destroy_workqueue(bitbang->workqueue);
-err1:
-        return status;
+        return spi_register_master(master);
 }
 EXPORT_SYMBOL_GPL(spi_bitbang_start);
 
@@ -490,10 +460,6 @@ int spi_bitbang_stop(struct spi_bitbang *bitbang)
 {
         spi_unregister_master(bitbang->master);
 
-        WARN_ON(!list_empty(&bitbang->queue));
-
-        destroy_workqueue(bitbang->workqueue);
-
         return 0;
 }
 EXPORT_SYMBOL_GPL(spi_bitbang_stop);
diff --git a/drivers/spi/spi-nuc900.c b/drivers/spi/spi-nuc900.c
index 150d85453c27..2ad3d74ac021 100644
--- a/drivers/spi/spi-nuc900.c
+++ b/drivers/spi/spi-nuc900.c
@@ -174,17 +174,6 @@ static void nuc900_spi_gobusy(struct nuc900_spi *hw)
         spin_unlock_irqrestore(&hw->lock, flags);
 }
 
-static int nuc900_spi_setupxfer(struct spi_device *spi,
-                                 struct spi_transfer *t)
-{
-        return 0;
-}
-
-static int nuc900_spi_setup(struct spi_device *spi)
-{
-        return 0;
-}
-
 static inline unsigned int hw_txbyte(struct nuc900_spi *hw, int count)
 {
         return hw->tx ? hw->tx[count] : 0;
@@ -377,10 +366,8 @@ static int nuc900_spi_probe(struct platform_device *pdev)
         master->num_chipselect     = hw->pdata->num_cs;
         master->bus_num            = hw->pdata->bus_num;
         hw->bitbang.master         = hw->master;
-        hw->bitbang.setup_transfer = nuc900_spi_setupxfer;
         hw->bitbang.chipselect     = nuc900_spi_chipsel;
         hw->bitbang.txrx_bufs      = nuc900_spi_txrx;
-        hw->bitbang.master->setup  = nuc900_spi_setup;
 
         hw->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         if (hw->res == NULL) {
diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c
index 09a942852593..fb56fcfdf65e 100644
--- a/drivers/spi/spi-xilinx.c
+++ b/drivers/spi/spi-xilinx.c
@@ -233,21 +233,6 @@ static int xilinx_spi_setup_transfer(struct spi_device *spi,
         return 0;
 }
 
-static int xilinx_spi_setup(struct spi_device *spi)
-{
-        /* always return 0, we can not check the number of bits.
-         * There are cases when SPI setup is called before any driver is
-         * there, in that case the SPI core defaults to 8 bits, which we
-         * do not support in some cases. But if we return an error, the
-         * SPI device would not be registered and no driver can get hold of it
-         * When the driver is there, it will call SPI setup again with the
-         * correct number of bits per transfer.
-         * If a driver setups with the wrong bit number, it will fail when
-         * it tries to do a transfer
-         */
-        return 0;
-}
-
 static void xilinx_spi_fill_tx_fifo(struct xilinx_spi *xspi)
 {
         u8 sr;
@@ -375,7 +360,6 @@ struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem,
         xspi->bitbang.chipselect = xilinx_spi_chipselect;
         xspi->bitbang.setup_transfer = xilinx_spi_setup_transfer;
         xspi->bitbang.txrx_bufs = xilinx_spi_txrx_bufs;
-        xspi->bitbang.master->setup = xilinx_spi_setup;
         init_completion(&xspi->done);
 
         if (!request_mem_region(mem->start, resource_size(mem),
diff --git a/include/linux/spi/spi_bitbang.h b/include/linux/spi/spi_bitbang.h
index f987a2bee16a..daebaba886aa 100644
--- a/include/linux/spi/spi_bitbang.h
+++ b/include/linux/spi/spi_bitbang.h
@@ -4,11 +4,7 @@
 #include <linux/workqueue.h>
 
 struct spi_bitbang {
-        struct workqueue_struct *workqueue;
-        struct work_struct      work;
-
         spinlock_t              lock;
-        struct list_head        queue;
         u8                      busy;
         u8                      use_dma;
         u8                      flags;          /* extra spi->mode support */
@@ -41,7 +37,6 @@ struct spi_bitbang {
  */
 extern int spi_bitbang_setup(struct spi_device *spi);
 extern void spi_bitbang_cleanup(struct spi_device *spi);
-extern int spi_bitbang_transfer(struct spi_device *spi, struct spi_message *m);
 extern int spi_bitbang_setup_transfer(struct spi_device *spi,
                                       struct spi_transfer *t);