Merge branch 'spi/next' of git://git.secretlab.ca/git/linux-2.6

* 'spi/next' of git://git.secretlab.ca/git/linux-2.6:
  spi/amba-pl022: work in polling or interrupt mode if pl022_dma_probe fails
  spi/spi_s3c24xx: Use spi_bitbang_stop instead of spi_unregister_master in s3c24xx_spi_remove
  spi/spi_nuc900: Use spi_bitbang_stop instead of spi_unregister_master in nuc900_spi_remove
  spi/spi_tegra: use spi_unregister_master() instead of spi_master_put()
  spi/spi_sh: use spi_unregister_master instead of spi_master_put in remove path
  spi: Use void pointers for data in simple SPI I/O operations
  spi/pl022: use cpu_relax in the busy loop
  spi/pl022: mark driver non-experimental
  spi/pl022: timeout on polled transfer v2
  spi/dw_spi: improve the interrupt mode with the batch ops
  spi/dw_spi: change poll mode transfer from byte ops to batch ops
  spi/dw_spi: remove the un-necessary flush()
  spi/dw_spi: unify the low level read/write routines

9 files changed, 96 insertions, 159 deletions

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index fc14b8dea0d7..fbd96b29530d 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -271,8 +271,8 @@ config SPI_ORION
           This enables using the SPI master controller on the Orion chips.
 
 config SPI_PL022
-        tristate "ARM AMBA PL022 SSP controller (EXPERIMENTAL)"
-        depends on ARM_AMBA && EXPERIMENTAL
+        tristate "ARM AMBA PL022 SSP controller"
+        depends on ARM_AMBA
         default y if MACH_U300
         default y if ARCH_REALVIEW
         default y if INTEGRATOR_IMPD1
diff --git a/drivers/spi/amba-pl022.c b/drivers/spi/amba-pl022.c
index 08de58e7f59f..6a9e58dd36c7 100644
--- a/drivers/spi/amba-pl022.c
+++ b/drivers/spi/amba-pl022.c
@@ -24,11 +24,6 @@
  * GNU General Public License for more details.
  */
 
-/*
- * TODO:
- * - add timeout on polled transfers
- */
-
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/device.h>
@@ -287,6 +282,8 @@
 
 #define CLEAR_ALL_INTERRUPTS  0x3
 
+#define SPI_POLLING_TIMEOUT 1000
+
 
 /*
  * The type of reading going on on this chip
@@ -1063,7 +1060,7 @@ static int __init pl022_dma_probe(struct pl022 *pl022)
                                             pl022->master_info->dma_filter,
                                             pl022->master_info->dma_rx_param);
         if (!pl022->dma_rx_channel) {
-                dev_err(&pl022->adev->dev, "no RX DMA channel!\n");
+                dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
                 goto err_no_rxchan;
         }
 
@@ -1071,13 +1068,13 @@ static int __init pl022_dma_probe(struct pl022 *pl022)
                                             pl022->master_info->dma_filter,
                                             pl022->master_info->dma_tx_param);
         if (!pl022->dma_tx_channel) {
-                dev_err(&pl022->adev->dev, "no TX DMA channel!\n");
+                dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
                 goto err_no_txchan;
         }
 
         pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
         if (!pl022->dummypage) {
-                dev_err(&pl022->adev->dev, "no DMA dummypage!\n");
+                dev_dbg(&pl022->adev->dev, "no DMA dummypage!\n");
                 goto err_no_dummypage;
         }
 
@@ -1093,6 +1090,8 @@ err_no_txchan:
         dma_release_channel(pl022->dma_rx_channel);
         pl022->dma_rx_channel = NULL;
 err_no_rxchan:
+        dev_err(&pl022->adev->dev,
+                        "Failed to work in dma mode, work without dma!\n");
         return -ENODEV;
 }
 
@@ -1378,6 +1377,7 @@ static void do_polling_transfer(struct pl022 *pl022)
         struct spi_transfer *transfer = NULL;
         struct spi_transfer *previous = NULL;
         struct chip_data *chip;
+        unsigned long time, timeout;
 
         chip = pl022->cur_chip;
         message = pl022->cur_msg;
@@ -1415,9 +1415,19 @@ static void do_polling_transfer(struct pl022 *pl022)
                        SSP_CR1(pl022->virtbase));
 
                 dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
-                /* FIXME: insert a timeout so we don't hang here indefinitely */
-                while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end)
+
+                timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
+                while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
+                        time = jiffies;
                         readwriter(pl022);
+                        if (time_after(time, timeout)) {
+                                dev_warn(&pl022->adev->dev,
+                                "%s: timeout!\n", __func__);
+                                message->state = STATE_ERROR;
+                                goto out;
+                        }
+                        cpu_relax();
+                }
 
                 /* Update total byte transferred */
                 message->actual_length += pl022->cur_transfer->len;
@@ -1426,7 +1436,7 @@ static void do_polling_transfer(struct pl022 *pl022)
                 /* Move to next transfer */
                 message->state = next_transfer(pl022);
         }
-
+out:
         /* Handle end of message */
         if (message->state == STATE_DONE)
                 message->status = 0;
@@ -2107,7 +2117,7 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id)
         if (platform_info->enable_dma) {
                 status = pl022_dma_probe(pl022);
                 if (status != 0)
-                        goto err_no_dma;
+                        platform_info->enable_dma = 0;
         }
 
         /* Initialize and start queue */
@@ -2143,7 +2153,6 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id)
  err_init_queue:
         destroy_queue(pl022);
         pl022_dma_remove(pl022);
- err_no_dma:
         free_irq(adev->irq[0], pl022);
  err_no_irq:
         clk_put(pl022->clk);
diff --git a/drivers/spi/dw_spi.c b/drivers/spi/dw_spi.c
index 871e337c917f..919fa9d9e16b 100644
--- a/drivers/spi/dw_spi.c
+++ b/drivers/spi/dw_spi.c
@@ -58,8 +58,6 @@ struct chip_data {
         u8 bits_per_word;
         u16 clk_div;            /* baud rate divider */
         u32 speed_hz;           /* baud rate */
-        int (*write)(struct dw_spi *dws);
-        int (*read)(struct dw_spi *dws);
         void (*cs_control)(u32 command);
 };
 
@@ -162,107 +160,70 @@ static inline void mrst_spi_debugfs_remove(struct dw_spi *dws)
 }
 #endif /* CONFIG_DEBUG_FS */
 
-static void wait_till_not_busy(struct dw_spi *dws)
+/* Return the max entries we can fill into tx fifo */
+static inline u32 tx_max(struct dw_spi *dws)
 {
-        unsigned long end = jiffies + 1 + usecs_to_jiffies(5000);
+        u32 tx_left, tx_room, rxtx_gap;
 
-        while (time_before(jiffies, end)) {
-                if (!(dw_readw(dws, sr) & SR_BUSY))
-                        return;
-                cpu_relax();
-        }
-        dev_err(&dws->master->dev,
-                "DW SPI: Status keeps busy for 5000us after a read/write!\n");
-}
-
-static void flush(struct dw_spi *dws)
-{
-        while (dw_readw(dws, sr) & SR_RF_NOT_EMPT) {
-                dw_readw(dws, dr);
-                cpu_relax();
-        }
-
-        wait_till_not_busy(dws);
-}
-
-static int null_writer(struct dw_spi *dws)
-{
-        u8 n_bytes = dws->n_bytes;
+        tx_left = (dws->tx_end - dws->tx) / dws->n_bytes;
+        tx_room = dws->fifo_len - dw_readw(dws, txflr);
 
-        if (!(dw_readw(dws, sr) & SR_TF_NOT_FULL)
-                || (dws->tx == dws->tx_end))
-                return 0;
-        dw_writew(dws, dr, 0);
-        dws->tx += n_bytes;
+        /*
+         * Another concern is about the tx/rx mismatch, we
+         * though to use (dws->fifo_len - rxflr - txflr) as
+         * one maximum value for tx, but it doesn't cover the
+         * data which is out of tx/rx fifo and inside the
+         * shift registers. So a control from sw point of
+         * view is taken.
+         */
+        rxtx_gap =  ((dws->rx_end - dws->rx) - (dws->tx_end - dws->tx))
+                        / dws->n_bytes;
 
-        wait_till_not_busy(dws);
-        return 1;
+        return min3(tx_left, tx_room, (u32) (dws->fifo_len - rxtx_gap));
 }
 
-static int null_reader(struct dw_spi *dws)
+/* Return the max entries we should read out of rx fifo */
+static inline u32 rx_max(struct dw_spi *dws)
 {
-        u8 n_bytes = dws->n_bytes;
+        u32 rx_left = (dws->rx_end - dws->rx) / dws->n_bytes;
 
-        while ((dw_readw(dws, sr) & SR_RF_NOT_EMPT)
-                && (dws->rx < dws->rx_end)) {
-                dw_readw(dws, dr);
-                dws->rx += n_bytes;
-        }
-        wait_till_not_busy(dws);
-        return dws->rx == dws->rx_end;
+        return min(rx_left, (u32)dw_readw(dws, rxflr));
 }
 
-static int u8_writer(struct dw_spi *dws)
+static void dw_writer(struct dw_spi *dws)
 {
-        if (!(dw_readw(dws, sr) & SR_TF_NOT_FULL)
-                || (dws->tx == dws->tx_end))
-                return 0;
+        u32 max = tx_max(dws);
+        u16 txw = 0;
 
-        dw_writew(dws, dr, *(u8 *)(dws->tx));
-        ++dws->tx;
-
-        wait_till_not_busy(dws);
-        return 1;
-}
-
-static int u8_reader(struct dw_spi *dws)
-{
-        while ((dw_readw(dws, sr) & SR_RF_NOT_EMPT)
-                && (dws->rx < dws->rx_end)) {
-                *(u8 *)(dws->rx) = dw_readw(dws, dr);
-                ++dws->rx;
+        while (max--) {
+                /* Set the tx word if the transfer's original "tx" is not null */
+                if (dws->tx_end - dws->len) {
+                        if (dws->n_bytes == 1)
+                                txw = *(u8 *)(dws->tx);
+                        else
+                                txw = *(u16 *)(dws->tx);
+                }
+                dw_writew(dws, dr, txw);
+                dws->tx += dws->n_bytes;
         }
-
-        wait_till_not_busy(dws);
-        return dws->rx == dws->rx_end;
 }
 
-static int u16_writer(struct dw_spi *dws)
+static void dw_reader(struct dw_spi *dws)
 {
-        if (!(dw_readw(dws, sr) & SR_TF_NOT_FULL)
-                || (dws->tx == dws->tx_end))
-                return 0;
+        u32 max = rx_max(dws);
+        u16 rxw;
 
-        dw_writew(dws, dr, *(u16 *)(dws->tx));
-        dws->tx += 2;
-
-        wait_till_not_busy(dws);
-        return 1;
-}
-
-static int u16_reader(struct dw_spi *dws)
-{
-        u16 temp;
-
-        while ((dw_readw(dws, sr) & SR_RF_NOT_EMPT)
-                && (dws->rx < dws->rx_end)) {
-                temp = dw_readw(dws, dr);
-                *(u16 *)(dws->rx) = temp;
-                dws->rx += 2;
+        while (max--) {
+                rxw = dw_readw(dws, dr);
+                /* Care rx only if the transfer's original "rx" is not null */
+                if (dws->rx_end - dws->len) {
+                        if (dws->n_bytes == 1)
+                                *(u8 *)(dws->rx) = rxw;
+                        else
+                                *(u16 *)(dws->rx) = rxw;
+                }
+                dws->rx += dws->n_bytes;
         }
-
-        wait_till_not_busy(dws);
-        return dws->rx == dws->rx_end;
 }
 
 static void *next_transfer(struct dw_spi *dws)
@@ -334,8 +295,7 @@ static void giveback(struct dw_spi *dws)
 
 static void int_error_stop(struct dw_spi *dws, const char *msg)
 {
-        /* Stop and reset hw */
-        flush(dws);
+        /* Stop the hw */
         spi_enable_chip(dws, 0);
 
         dev_err(&dws->master->dev, "%s\n", msg);
@@ -362,35 +322,28 @@ EXPORT_SYMBOL_GPL(dw_spi_xfer_done);
 
 static irqreturn_t interrupt_transfer(struct dw_spi *dws)
 {
-        u16 irq_status, irq_mask = 0x3f;
-        u32 int_level = dws->fifo_len / 2;
-        u32 left;
+        u16 irq_status = dw_readw(dws, isr);
 
-        irq_status = dw_readw(dws, isr) & irq_mask;
         /* Error handling */
         if (irq_status & (SPI_INT_TXOI | SPI_INT_RXOI | SPI_INT_RXUI)) {
                 dw_readw(dws, txoicr);
                 dw_readw(dws, rxoicr);
                 dw_readw(dws, rxuicr);
-                int_error_stop(dws, "interrupt_transfer: fifo overrun");
+                int_error_stop(dws, "interrupt_transfer: fifo overrun/underrun");
                 return IRQ_HANDLED;
         }
 
+        dw_reader(dws);
+        if (dws->rx_end == dws->rx) {
+                spi_mask_intr(dws, SPI_INT_TXEI);
+                dw_spi_xfer_done(dws);
+                return IRQ_HANDLED;
+        }
         if (irq_status & SPI_INT_TXEI) {
                 spi_mask_intr(dws, SPI_INT_TXEI);
-
-                left = (dws->tx_end - dws->tx) / dws->n_bytes;
-                left = (left > int_level) ? int_level : left;
-
-                while (left--)
-                        dws->write(dws);
-                dws->read(dws);
-
-                /* Re-enable the IRQ if there is still data left to tx */
-                if (dws->tx_end > dws->tx)
-                        spi_umask_intr(dws, SPI_INT_TXEI);
-                else
-                        dw_spi_xfer_done(dws);
+                dw_writer(dws);
+                /* Enable TX irq always, it will be disabled when RX finished */
+                spi_umask_intr(dws, SPI_INT_TXEI);
         }
 
         return IRQ_HANDLED;
@@ -399,15 +352,13 @@ static irqreturn_t interrupt_transfer(struct dw_spi *dws)
 static irqreturn_t dw_spi_irq(int irq, void *dev_id)
 {
         struct dw_spi *dws = dev_id;
-        u16 irq_status, irq_mask = 0x3f;
+        u16 irq_status = dw_readw(dws, isr) & 0x3f;
 
-        irq_status = dw_readw(dws, isr) & irq_mask;
         if (!irq_status)
                 return IRQ_NONE;
 
         if (!dws->cur_msg) {
                 spi_mask_intr(dws, SPI_INT_TXEI);
-                /* Never fail */
                 return IRQ_HANDLED;
         }
 
@@ -417,13 +368,11 @@ static irqreturn_t dw_spi_irq(int irq, void *dev_id)
 /* Must be called inside pump_transfers() */
 static void poll_transfer(struct dw_spi *dws)
 {
-        while (dws->write(dws))
-                dws->read(dws);
-        /*
-         * There is a possibility that the last word of a transaction
-         * will be lost if data is not ready. Re-read to solve this issue.
-         */
-        dws->read(dws);
+        do {
+                dw_writer(dws);
+                dw_reader(dws);
+                cpu_relax();
+        } while (dws->rx_end > dws->rx);
 
         dw_spi_xfer_done(dws);
 }
@@ -483,8 +432,6 @@ static void pump_transfers(unsigned long data)
         dws->tx_end = dws->tx + transfer->len;
         dws->rx = transfer->rx_buf;
         dws->rx_end = dws->rx + transfer->len;
-        dws->write = dws->tx ? chip->write : null_writer;
-        dws->read = dws->rx ? chip->read : null_reader;
         dws->cs_change = transfer->cs_change;
         dws->len = dws->cur_transfer->len;
         if (chip != dws->prev_chip)
@@ -518,20 +465,8 @@ static void pump_transfers(unsigned long data)
 
                 switch (bits) {
                 case 8:
-                        dws->n_bytes = 1;
-                        dws->dma_width = 1;
-                        dws->read = (dws->read != null_reader) ?
-                                        u8_reader : null_reader;
-                        dws->write = (dws->write != null_writer) ?
-                                        u8_writer : null_writer;
-                        break;
                 case 16:
-                        dws->n_bytes = 2;
-                        dws->dma_width = 2;
-                        dws->read = (dws->read != null_reader) ?
-                                        u16_reader : null_reader;
-                        dws->write = (dws->write != null_writer) ?
-                                        u16_writer : null_writer;
+                        dws->n_bytes = dws->dma_width = bits >> 3;
                         break;
                 default:
                         printk(KERN_ERR "MRST SPI0: unsupported bits:"
@@ -575,7 +510,7 @@ static void pump_transfers(unsigned long data)
                 txint_level = dws->fifo_len / 2;
                 txint_level = (templen > txint_level) ? txint_level : templen;
 
-                imask |= SPI_INT_TXEI;
+                imask |= SPI_INT_TXEI | SPI_INT_TXOI | SPI_INT_RXUI | SPI_INT_RXOI;
                 dws->transfer_handler = interrupt_transfer;
         }
 
@@ -733,13 +668,9 @@ static int dw_spi_setup(struct spi_device *spi)
         if (spi->bits_per_word <= 8) {
                 chip->n_bytes = 1;
                 chip->dma_width = 1;
-                chip->read = u8_reader;
-                chip->write = u8_writer;
         } else if (spi->bits_per_word <= 16) {
                 chip->n_bytes = 2;
                 chip->dma_width = 2;
-                chip->read = u16_reader;
-                chip->write = u16_writer;
         } else {
                 /* Never take >16b case for MRST SPIC */
                 dev_err(&spi->dev, "invalid wordsize\n");
@@ -851,7 +782,6 @@ static void spi_hw_init(struct dw_spi *dws)
         spi_enable_chip(dws, 0);
         spi_mask_intr(dws, 0xff);
         spi_enable_chip(dws, 1);
-        flush(dws);
 
         /*
          * Try to detect the FIFO depth if not set by interface driver,
diff --git a/drivers/spi/dw_spi.h b/drivers/spi/dw_spi.h
index b23e452adaf7..7a5e78d2a5cb 100644
--- a/drivers/spi/dw_spi.h
+++ b/drivers/spi/dw_spi.h
@@ -137,8 +137,6 @@ struct dw_spi {
         u8                      max_bits_per_word;      /* maxim is 16b */
         u32                     dma_width;
         int                     cs_change;
-        int                     (*write)(struct dw_spi *dws);
-        int                     (*read)(struct dw_spi *dws);
         irqreturn_t             (*transfer_handler)(struct dw_spi *dws);
         void                    (*cs_control)(u32 command);
 
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 82b9a428c323..2e13a14bba3f 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1047,8 +1047,8 @@ static u8	*buf;
  * spi_{async,sync}() calls with dma-safe buffers.
  */
 int spi_write_then_read(struct spi_device *spi,
-                const u8 *txbuf, unsigned n_tx,
-                u8 *rxbuf, unsigned n_rx)
+                const void *txbuf, unsigned n_tx,
+                void *rxbuf, unsigned n_rx)
 {
         static DEFINE_MUTEX(lock);
 
diff --git a/drivers/spi/spi_nuc900.c b/drivers/spi/spi_nuc900.c
index d5be18b3078c..3cd15f690f16 100644
--- a/drivers/spi/spi_nuc900.c
+++ b/drivers/spi/spi_nuc900.c
@@ -463,7 +463,7 @@ static int __devexit nuc900_spi_remove(struct platform_device *dev)
 
         platform_set_drvdata(dev, NULL);
 
-        spi_unregister_master(hw->master);
+        spi_bitbang_stop(&hw->bitbang);
 
         clk_disable(hw->clk);
         clk_put(hw->clk);
diff --git a/drivers/spi/spi_s3c24xx.c b/drivers/spi/spi_s3c24xx.c
index 151a95e40653..1a5fcabfd565 100644
--- a/drivers/spi/spi_s3c24xx.c
+++ b/drivers/spi/spi_s3c24xx.c
@@ -668,7 +668,7 @@ static int __exit s3c24xx_spi_remove(struct platform_device *dev)
 
         platform_set_drvdata(dev, NULL);
 
-        spi_unregister_master(hw->master);
+        spi_bitbang_stop(&hw->bitbang);
 
         clk_disable(hw->clk);
         clk_put(hw->clk);
diff --git a/drivers/spi/spi_sh.c b/drivers/spi/spi_sh.c
index 869a07d375d6..9eedd71ad898 100644
--- a/drivers/spi/spi_sh.c
+++ b/drivers/spi/spi_sh.c
@@ -427,10 +427,10 @@ static int __devexit spi_sh_remove(struct platform_device *pdev)
 {
         struct spi_sh_data *ss = dev_get_drvdata(&pdev->dev);
 
+        spi_unregister_master(ss->master);
         destroy_workqueue(ss->workqueue);
         free_irq(ss->irq, ss);
         iounmap(ss->addr);
-        spi_master_put(ss->master);
 
         return 0;
 }
diff --git a/drivers/spi/spi_tegra.c b/drivers/spi/spi_tegra.c
index 891e5909038c..6c3aa6ecaade 100644
--- a/drivers/spi/spi_tegra.c
+++ b/drivers/spi/spi_tegra.c
@@ -578,6 +578,7 @@ static int __devexit spi_tegra_remove(struct platform_device *pdev)
         master = dev_get_drvdata(&pdev->dev);
         tspi = spi_master_get_devdata(master);
 
+        spi_unregister_master(master);
         tegra_dma_free_channel(tspi->rx_dma);
 
         dma_free_coherent(&pdev->dev, sizeof(u32) * BB_LEN,
@@ -586,7 +587,6 @@ static int __devexit spi_tegra_remove(struct platform_device *pdev)
         clk_put(tspi->clk);
         iounmap(tspi->base);
 
-        spi_master_put(master);
         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         release_mem_region(r->start, (r->end - r->start) + 1);