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authorLinus Torvalds <torvalds@linux-foundation.org>2011-05-26 12:13:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-05-26 12:13:22 -0700
commit20e0ec119b2c6cc412addefbe169f4f5e38701e8 (patch)
treefd8b882f4027f1a60857cbcd3bb85a83261db07f /drivers/spi
parent829ae2732998e628d762b97627e4e5cc6c1b5625 (diff)
parent43c640157d4366a3ea9ba01f903ea892f46376ee (diff)
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
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/Kconfig4
-rw-r--r--drivers/spi/amba-pl022.c35
-rw-r--r--drivers/spi/dw_spi.c202
-rw-r--r--drivers/spi/dw_spi.h2
-rw-r--r--drivers/spi/spi.c4
-rw-r--r--drivers/spi/spi_nuc900.c2
-rw-r--r--drivers/spi/spi_s3c24xx.c2
-rw-r--r--drivers/spi/spi_sh.c2
-rw-r--r--drivers/spi/spi_tegra.c2
9 files changed, 96 insertions, 159 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index fc14b8dea0d..fbd96b29530 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 08de58e7f59..6a9e58dd36c 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 871e337c917..919fa9d9e16 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 b23e452adaf..7a5e78d2a5c 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 82b9a428c32..2e13a14bba3 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 d5be18b3078..3cd15f690f1 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 151a95e4065..1a5fcabfd56 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 869a07d375d..9eedd71ad89 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 891e5909038..6c3aa6ecaad 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);