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authorLinus Torvalds <torvalds@linux-foundation.org>2010-08-14 11:54:09 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-08-14 11:54:09 -0700
commitb171aa27700c78511086a759383b033949c9d7f0 (patch)
tree2775b0682ea342dd49c5b997de248da73ec83049
parent11ac552477e32835cb6970bf0a70c210807f5673 (diff)
parentb4225885deb569f7afcf1f3a9f069f74cc9db591 (diff)
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Merge branch 'next-spi' of git://git.secretlab.ca/git/linux-2.6
* 'next-spi' of git://git.secretlab.ca/git/linux-2.6: spi/amba_pl022: Fix probe and remove hook section annotations. spi/mpc5121: change annotations for probe and remove functions spi/bitbang: reinitialize transfer parameters for every message spi/spi-gpio: add support for controllers without MISO or MOSI pin spi/bitbang: add support for SPI_MASTER_NO_{TX, RX} modes SPI100k: Fix 8-bit and RX-only transfers spi/mmc_spi: mmc_spi adaptations for SPI bus locking API spi/mmc_spi: SPI bus locking API, using mutex Fix trivial conflict in drivers/spi/mpc512x_psc_spi.c due to 'struct of_device' => 'struct platform_device' rename and __init/__exit to __devinit/__devexit fix.
-rw-r--r--drivers/mmc/host/mmc_spi.c59
-rw-r--r--drivers/spi/amba-pl022.c6
-rw-r--r--drivers/spi/mpc512x_psc_spi.c16
-rw-r--r--drivers/spi/omap_spi_100k.c23
-rw-r--r--drivers/spi/spi.c225
-rw-r--r--drivers/spi/spi_bitbang.c9
-rw-r--r--drivers/spi/spi_bitbang_txrx.h16
-rw-r--r--drivers/spi/spi_butterfly.c2
-rw-r--r--drivers/spi/spi_gpio.c109
-rw-r--r--drivers/spi/spi_lm70llp.c2
-rw-r--r--drivers/spi/spi_s3c24xx_gpio.c8
-rw-r--r--drivers/spi/spi_sh_sci.c8
-rw-r--r--include/linux/spi/spi.h12
-rw-r--r--include/linux/spi/spi_gpio.h5
14 files changed, 353 insertions, 147 deletions
diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c
index 1145ea0792e6..62a35822003e 100644
--- a/drivers/mmc/host/mmc_spi.c
+++ b/drivers/mmc/host/mmc_spi.c
@@ -182,7 +182,7 @@ mmc_spi_readbytes(struct mmc_spi_host *host, unsigned len)
host->data_dma, sizeof(*host->data),
DMA_FROM_DEVICE);
- status = spi_sync(host->spi, &host->readback);
+ status = spi_sync_locked(host->spi, &host->readback);
if (host->dma_dev)
dma_sync_single_for_cpu(host->dma_dev,
@@ -541,7 +541,7 @@ mmc_spi_command_send(struct mmc_spi_host *host,
host->data_dma, sizeof(*host->data),
DMA_BIDIRECTIONAL);
}
- status = spi_sync(host->spi, &host->m);
+ status = spi_sync_locked(host->spi, &host->m);
if (host->dma_dev)
dma_sync_single_for_cpu(host->dma_dev,
@@ -685,7 +685,7 @@ mmc_spi_writeblock(struct mmc_spi_host *host, struct spi_transfer *t,
host->data_dma, sizeof(*scratch),
DMA_BIDIRECTIONAL);
- status = spi_sync(spi, &host->m);
+ status = spi_sync_locked(spi, &host->m);
if (status != 0) {
dev_dbg(&spi->dev, "write error (%d)\n", status);
@@ -822,7 +822,7 @@ mmc_spi_readblock(struct mmc_spi_host *host, struct spi_transfer *t,
DMA_FROM_DEVICE);
}
- status = spi_sync(spi, &host->m);
+ status = spi_sync_locked(spi, &host->m);
if (host->dma_dev) {
dma_sync_single_for_cpu(host->dma_dev,
@@ -1018,7 +1018,7 @@ mmc_spi_data_do(struct mmc_spi_host *host, struct mmc_command *cmd,
host->data_dma, sizeof(*scratch),
DMA_BIDIRECTIONAL);
- tmp = spi_sync(spi, &host->m);
+ tmp = spi_sync_locked(spi, &host->m);
if (host->dma_dev)
dma_sync_single_for_cpu(host->dma_dev,
@@ -1084,6 +1084,9 @@ static void mmc_spi_request(struct mmc_host *mmc, struct mmc_request *mrq)
}
#endif
+ /* request exclusive bus access */
+ spi_bus_lock(host->spi->master);
+
/* issue command; then optionally data and stop */
status = mmc_spi_command_send(host, mrq, mrq->cmd, mrq->data != NULL);
if (status == 0 && mrq->data) {
@@ -1094,6 +1097,9 @@ static void mmc_spi_request(struct mmc_host *mmc, struct mmc_request *mrq)
mmc_cs_off(host);
}
+ /* release the bus */
+ spi_bus_unlock(host->spi->master);
+
mmc_request_done(host->mmc, mrq);
}
@@ -1290,23 +1296,6 @@ mmc_spi_detect_irq(int irq, void *mmc)
return IRQ_HANDLED;
}
-struct count_children {
- unsigned n;
- struct bus_type *bus;
-};
-
-static int maybe_count_child(struct device *dev, void *c)
-{
- struct count_children *ccp = c;
-
- if (dev->bus == ccp->bus) {
- if (ccp->n)
- return -EBUSY;
- ccp->n++;
- }
- return 0;
-}
-
static int mmc_spi_probe(struct spi_device *spi)
{
void *ones;
@@ -1338,32 +1327,6 @@ static int mmc_spi_probe(struct spi_device *spi)
return status;
}
- /* We can use the bus safely iff nobody else will interfere with us.
- * Most commands consist of one SPI message to issue a command, then
- * several more to collect its response, then possibly more for data
- * transfer. Clocking access to other devices during that period will
- * corrupt the command execution.
- *
- * Until we have software primitives which guarantee non-interference,
- * we'll aim for a hardware-level guarantee.
- *
- * REVISIT we can't guarantee another device won't be added later...
- */
- if (spi->master->num_chipselect > 1) {
- struct count_children cc;
-
- cc.n = 0;
- cc.bus = spi->dev.bus;
- status = device_for_each_child(spi->dev.parent, &cc,
- maybe_count_child);
- if (status < 0) {
- dev_err(&spi->dev, "can't share SPI bus\n");
- return status;
- }
-
- dev_warn(&spi->dev, "ASSUMING SPI bus stays unshared!\n");
- }
-
/* We need a supply of ones to transmit. This is the only time
* the CPU touches these, so cache coherency isn't a concern.
*
diff --git a/drivers/spi/amba-pl022.c b/drivers/spi/amba-pl022.c
index f0a1418ce660..acd35d1ebd12 100644
--- a/drivers/spi/amba-pl022.c
+++ b/drivers/spi/amba-pl022.c
@@ -1723,7 +1723,7 @@ static void pl022_cleanup(struct spi_device *spi)
}
-static int __init
+static int __devinit
pl022_probe(struct amba_device *adev, struct amba_id *id)
{
struct device *dev = &adev->dev;
@@ -1838,7 +1838,7 @@ pl022_probe(struct amba_device *adev, struct amba_id *id)
return status;
}
-static int __exit
+static int __devexit
pl022_remove(struct amba_device *adev)
{
struct pl022 *pl022 = amba_get_drvdata(adev);
@@ -1970,7 +1970,7 @@ static struct amba_driver pl022_driver = {
},
.id_table = pl022_ids,
.probe = pl022_probe,
- .remove = __exit_p(pl022_remove),
+ .remove = __devexit_p(pl022_remove),
.suspend = pl022_suspend,
.resume = pl022_resume,
};
diff --git a/drivers/spi/mpc512x_psc_spi.c b/drivers/spi/mpc512x_psc_spi.c
index cddbfceb324f..77d9e7ee8b27 100644
--- a/drivers/spi/mpc512x_psc_spi.c
+++ b/drivers/spi/mpc512x_psc_spi.c
@@ -406,9 +406,9 @@ static irqreturn_t mpc512x_psc_spi_isr(int irq, void *dev_id)
}
/* bus_num is used only for the case dev->platform_data == NULL */
-static int __init mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr,
- u32 size, unsigned int irq,
- s16 bus_num)
+static int __devinit mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr,
+ u32 size, unsigned int irq,
+ s16 bus_num)
{
struct fsl_spi_platform_data *pdata = dev->platform_data;
struct mpc512x_psc_spi *mps;
@@ -492,7 +492,7 @@ free_master:
return ret;
}
-static int __exit mpc512x_psc_spi_do_remove(struct device *dev)
+static int __devexit mpc512x_psc_spi_do_remove(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct mpc512x_psc_spi *mps = spi_master_get_devdata(master);
@@ -507,8 +507,8 @@ static int __exit mpc512x_psc_spi_do_remove(struct device *dev)
return 0;
}
-static int __init mpc512x_psc_spi_of_probe(struct platform_device *op,
- const struct of_device_id *match)
+static int __devinit mpc512x_psc_spi_of_probe(struct platform_device *op,
+ const struct of_device_id *match)
{
const u32 *regaddr_p;
u64 regaddr64, size64;
@@ -539,7 +539,7 @@ static int __init mpc512x_psc_spi_of_probe(struct platform_device *op,
irq_of_parse_and_map(op->dev.of_node, 0), id);
}
-static int __exit mpc512x_psc_spi_of_remove(struct platform_device *op)
+static int __devexit mpc512x_psc_spi_of_remove(struct platform_device *op)
{
return mpc512x_psc_spi_do_remove(&op->dev);
}
@@ -553,7 +553,7 @@ MODULE_DEVICE_TABLE(of, mpc512x_psc_spi_of_match);
static struct of_platform_driver mpc512x_psc_spi_of_driver = {
.probe = mpc512x_psc_spi_of_probe,
- .remove = __exit_p(mpc512x_psc_spi_of_remove),
+ .remove = __devexit_p(mpc512x_psc_spi_of_remove),
.driver = {
.name = "mpc512x-psc-spi",
.owner = THIS_MODULE,
diff --git a/drivers/spi/omap_spi_100k.c b/drivers/spi/omap_spi_100k.c
index 24668b30a52d..9bd1c92ad96e 100644
--- a/drivers/spi/omap_spi_100k.c
+++ b/drivers/spi/omap_spi_100k.c
@@ -141,7 +141,12 @@ static void spi100k_write_data(struct spi_master *master, int len, int data)
{
struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
- /* write 16-bit word */
+ /* write 16-bit word, shifting 8-bit data if necessary */
+ if (len <= 8) {
+ data <<= 8;
+ len = 16;
+ }
+
spi100k_enable_clock(master);
writew( data , spi100k->base + SPI_TX_MSB);
@@ -162,6 +167,10 @@ static int spi100k_read_data(struct spi_master *master, int len)
int dataH,dataL;
struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
+ /* Always do at least 16 bits */
+ if (len <= 8)
+ len = 16;
+
spi100k_enable_clock(master);
writew(SPI_CTRL_SEN(0) |
SPI_CTRL_WORD_SIZE(len) |
@@ -214,10 +223,6 @@ omap1_spi100k_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
c = count;
word_len = cs->word_len;
- /* RX_ONLY mode needs dummy data in TX reg */
- if (xfer->tx_buf == NULL)
- spi100k_write_data(spi->master,word_len, 0);
-
if (word_len <= 8) {
u8 *rx;
const u8 *tx;
@@ -227,9 +232,9 @@ omap1_spi100k_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
do {
c-=1;
if (xfer->tx_buf != NULL)
- spi100k_write_data(spi->master,word_len, *tx);
+ spi100k_write_data(spi->master, word_len, *tx++);
if (xfer->rx_buf != NULL)
- *rx = spi100k_read_data(spi->master,word_len);
+ *rx++ = spi100k_read_data(spi->master, word_len);
} while(c);
} else if (word_len <= 16) {
u16 *rx;
@@ -380,10 +385,6 @@ static void omap1_spi100k_work(struct work_struct *work)
if (t->len) {
unsigned count;
- /* RX_ONLY mode needs dummy data in TX reg */
- if (t->tx_buf == NULL)
- spi100k_write_data(spi->master, 8, 0);
-
count = omap1_spi100k_txrx_pio(spi, t);
m->actual_length += count;
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 1bb1b88780ce..a9e5c79ae52a 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -528,6 +528,10 @@ int spi_register_master(struct spi_master *master)
dynamic = 1;
}
+ spin_lock_init(&master->bus_lock_spinlock);
+ mutex_init(&master->bus_lock_mutex);
+ master->bus_lock_flag = 0;
+
/* register the device, then userspace will see it.
* registration fails if the bus ID is in use.
*/
@@ -670,6 +674,35 @@ int spi_setup(struct spi_device *spi)
}
EXPORT_SYMBOL_GPL(spi_setup);
+static int __spi_async(struct spi_device *spi, struct spi_message *message)
+{
+ struct spi_master *master = spi->master;
+
+ /* Half-duplex links include original MicroWire, and ones with
+ * only one data pin like SPI_3WIRE (switches direction) or where
+ * either MOSI or MISO is missing. They can also be caused by
+ * software limitations.
+ */
+ if ((master->flags & SPI_MASTER_HALF_DUPLEX)
+ || (spi->mode & SPI_3WIRE)) {
+ struct spi_transfer *xfer;
+ unsigned flags = master->flags;
+
+ list_for_each_entry(xfer, &message->transfers, transfer_list) {
+ if (xfer->rx_buf && xfer->tx_buf)
+ return -EINVAL;
+ if ((flags & SPI_MASTER_NO_TX) && xfer->tx_buf)
+ return -EINVAL;
+ if ((flags & SPI_MASTER_NO_RX) && xfer->rx_buf)
+ return -EINVAL;
+ }
+ }
+
+ message->spi = spi;
+ message->status = -EINPROGRESS;
+ return master->transfer(spi, message);
+}
+
/**
* spi_async - asynchronous SPI transfer
* @spi: device with which data will be exchanged
@@ -702,33 +735,68 @@ EXPORT_SYMBOL_GPL(spi_setup);
int spi_async(struct spi_device *spi, struct spi_message *message)
{
struct spi_master *master = spi->master;
+ int ret;
+ unsigned long flags;
- /* Half-duplex links include original MicroWire, and ones with
- * only one data pin like SPI_3WIRE (switches direction) or where
- * either MOSI or MISO is missing. They can also be caused by
- * software limitations.
- */
- if ((master->flags & SPI_MASTER_HALF_DUPLEX)
- || (spi->mode & SPI_3WIRE)) {
- struct spi_transfer *xfer;
- unsigned flags = master->flags;
+ spin_lock_irqsave(&master->bus_lock_spinlock, flags);
- list_for_each_entry(xfer, &message->transfers, transfer_list) {
- if (xfer->rx_buf && xfer->tx_buf)
- return -EINVAL;
- if ((flags & SPI_MASTER_NO_TX) && xfer->tx_buf)
- return -EINVAL;
- if ((flags & SPI_MASTER_NO_RX) && xfer->rx_buf)
- return -EINVAL;
- }
- }
+ if (master->bus_lock_flag)
+ ret = -EBUSY;
+ else
+ ret = __spi_async(spi, message);
- message->spi = spi;
- message->status = -EINPROGRESS;
- return master->transfer(spi, message);
+ spin_unlock_irqrestore(&master->bus_lock_spinlock, flags);
+
+ return ret;
}
EXPORT_SYMBOL_GPL(spi_async);
+/**
+ * spi_async_locked - version of spi_async with exclusive bus usage
+ * @spi: device with which data will be exchanged
+ * @message: describes the data transfers, including completion callback
+ * Context: any (irqs may be blocked, etc)
+ *
+ * This call may be used in_irq and other contexts which can't sleep,
+ * as well as from task contexts which can sleep.
+ *
+ * The completion callback is invoked in a context which can't sleep.
+ * Before that invocation, the value of message->status is undefined.
+ * When the callback is issued, message->status holds either zero (to
+ * indicate complete success) or a negative error code. After that
+ * callback returns, the driver which issued the transfer request may
+ * deallocate the associated memory; it's no longer in use by any SPI
+ * core or controller driver code.
+ *
+ * Note that although all messages to a spi_device are handled in
+ * FIFO order, messages may go to different devices in other orders.
+ * Some device might be higher priority, or have various "hard" access
+ * time requirements, for example.
+ *
+ * On detection of any fault during the transfer, processing of
+ * the entire message is aborted, and the device is deselected.
+ * Until returning from the associated message completion callback,
+ * no other spi_message queued to that device will be processed.
+ * (This rule applies equally to all the synchronous transfer calls,
+ * which are wrappers around this core asynchronous primitive.)
+ */
+int spi_async_locked(struct spi_device *spi, struct spi_message *message)
+{
+ struct spi_master *master = spi->master;
+ int ret;
+ unsigned long flags;
+
+ spin_lock_irqsave(&master->bus_lock_spinlock, flags);
+
+ ret = __spi_async(spi, message);
+
+ spin_unlock_irqrestore(&master->bus_lock_spinlock, flags);
+
+ return ret;
+
+}
+EXPORT_SYMBOL_GPL(spi_async_locked);
+
/*-------------------------------------------------------------------------*/
@@ -742,6 +810,32 @@ static void spi_complete(void *arg)
complete(arg);
}
+static int __spi_sync(struct spi_device *spi, struct spi_message *message,
+ int bus_locked)
+{
+ DECLARE_COMPLETION_ONSTACK(done);
+ int status;
+ struct spi_master *master = spi->master;
+
+ message->complete = spi_complete;
+ message->context = &done;
+
+ if (!bus_locked)
+ mutex_lock(&master->bus_lock_mutex);
+
+ status = spi_async_locked(spi, message);
+
+ if (!bus_locked)
+ mutex_unlock(&master->bus_lock_mutex);
+
+ if (status == 0) {
+ wait_for_completion(&done);
+ status = message->status;
+ }
+ message->context = NULL;
+ return status;
+}
+
/**
* spi_sync - blocking/synchronous SPI data transfers
* @spi: device with which data will be exchanged
@@ -765,21 +859,86 @@ static void spi_complete(void *arg)
*/
int spi_sync(struct spi_device *spi, struct spi_message *message)
{
- DECLARE_COMPLETION_ONSTACK(done);
- int status;
-
- message->complete = spi_complete;
- message->context = &done;
- status = spi_async(spi, message);
- if (status == 0) {
- wait_for_completion(&done);
- status = message->status;
- }
- message->context = NULL;
- return status;
+ return __spi_sync(spi, message, 0);
}
EXPORT_SYMBOL_GPL(spi_sync);
+/**
+ * spi_sync_locked - version of spi_sync with exclusive bus usage
+ * @spi: device with which data will be exchanged
+ * @message: describes the data transfers
+ * Context: can sleep
+ *
+ * This call may only be used from a context that may sleep. The sleep
+ * is non-interruptible, and has no timeout. Low-overhead controller
+ * drivers may DMA directly into and out of the message buffers.
+ *
+ * This call should be used by drivers that require exclusive access to the
+ * SPI bus. It has to be preceeded by a spi_bus_lock call. The SPI bus must
+ * be released by a spi_bus_unlock call when the exclusive access is over.
+ *
+ * It returns zero on success, else a negative error code.
+ */
+int spi_sync_locked(struct spi_device *spi, struct spi_message *message)
+{
+ return __spi_sync(spi, message, 1);
+}
+EXPORT_SYMBOL_GPL(spi_sync_locked);
+
+/**
+ * spi_bus_lock - obtain a lock for exclusive SPI bus usage
+ * @master: SPI bus master that should be locked for exclusive bus access
+ * Context: can sleep
+ *
+ * This call may only be used from a context that may sleep. The sleep
+ * is non-interruptible, and has no timeout.
+ *
+ * This call should be used by drivers that require exclusive access to the
+ * SPI bus. The SPI bus must be released by a spi_bus_unlock call when the
+ * exclusive access is over. Data transfer must be done by spi_sync_locked
+ * and spi_async_locked calls when the SPI bus lock is held.
+ *
+ * It returns zero on success, else a negative error code.
+ */
+int spi_bus_lock(struct spi_master *master)
+{
+ unsigned long flags;
+
+ mutex_lock(&master->bus_lock_mutex);
+
+ spin_lock_irqsave(&master->bus_lock_spinlock, flags);
+ master->bus_lock_flag = 1;
+ spin_unlock_irqrestore(&master->bus_lock_spinlock, flags);
+
+ /* mutex remains locked until spi_bus_unlock is called */
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(spi_bus_lock);
+
+/**
+ * spi_bus_unlock - release the lock for exclusive SPI bus usage
+ * @master: SPI bus master that was locked for exclusive bus access
+ * Context: can sleep
+ *
+ * This call may only be used from a context that may sleep. The sleep
+ * is non-interruptible, and has no timeout.
+ *
+ * This call releases an SPI bus lock previously obtained by an spi_bus_lock
+ * call.
+ *
+ * It returns zero on success, else a negative error code.
+ */
+int spi_bus_unlock(struct spi_master *master)
+{
+ master->bus_lock_flag = 0;
+
+ mutex_unlock(&master->bus_lock_mutex);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(spi_bus_unlock);
+
/* portable code must never pass more than 32 bytes */
#define SPI_BUFSIZ max(32,SMP_CACHE_BYTES)
diff --git a/drivers/spi/spi_bitbang.c b/drivers/spi/spi_bitbang.c
index 5265330a528f..8b55724d5f39 100644
--- a/drivers/spi/spi_bitbang.c
+++ b/drivers/spi/spi_bitbang.c
@@ -259,7 +259,6 @@ static void bitbang_work(struct work_struct *work)
struct spi_bitbang *bitbang =
container_of(work, struct spi_bitbang, work);
unsigned long flags;
- int do_setup = -1;
int (*setup_transfer)(struct spi_device *,
struct spi_transfer *);
@@ -275,6 +274,7 @@ static void bitbang_work(struct work_struct *work)
unsigned tmp;
unsigned cs_change;
int status;
+ int do_setup = -1;
m = container_of(bitbang->queue.next, struct spi_message,
queue);
@@ -307,6 +307,8 @@ static void bitbang_work(struct work_struct *work)
status = setup_transfer(spi, t);
if (status < 0)
break;
+ if (do_setup == -1)
+ do_setup = 0;
}
/* set up default clock polarity, and activate chip;
@@ -367,11 +369,6 @@ static void bitbang_work(struct work_struct *work)
m->status = status;
m->complete(m->context);
- /* restore speed and wordsize if it was overridden */
- if (do_setup == 1)
- setup_transfer(spi, NULL);
- do_setup = 0;
-
/* normally deactivate chipselect ... unless no error and
* cs_change has hinted that the next message will probably
* be for this chip too.
diff --git a/drivers/spi/spi_bitbang_txrx.h b/drivers/spi/spi_bitbang_txrx.h
index fc033bbf9180..c16bf853c3eb 100644
--- a/drivers/spi/spi_bitbang_txrx.h
+++ b/drivers/spi/spi_bitbang_txrx.h
@@ -44,7 +44,7 @@
static inline u32
bitbang_txrx_be_cpha0(struct spi_device *spi,
- unsigned nsecs, unsigned cpol,
+ unsigned nsecs, unsigned cpol, unsigned flags,
u32 word, u8 bits)
{
/* if (cpol == 0) this is SPI_MODE_0; else this is SPI_MODE_2 */
@@ -53,7 +53,8 @@ bitbang_txrx_be_cpha0(struct spi_device *spi,
for (word <<= (32 - bits); likely(bits); bits--) {
/* setup MSB (to slave) on trailing edge */
- setmosi(spi, word & (1 << 31));
+ if ((flags & SPI_MASTER_NO_TX) == 0)
+ setmosi(spi, word & (1 << 31));
spidelay(nsecs); /* T(setup) */
setsck(spi, !cpol);
@@ -61,7 +62,8 @@ bitbang_txrx_be_cpha0(struct spi_device *spi,
/* sample MSB (from slave) on leading edge */
word <<= 1;
- word |= getmiso(spi);
+ if ((flags & SPI_MASTER_NO_RX) == 0)
+ word |= getmiso(spi);
setsck(spi, cpol);
}
return word;
@@ -69,7 +71,7 @@ bitbang_txrx_be_cpha0(struct spi_device *spi,
static inline u32
bitbang_txrx_be_cpha1(struct spi_device *spi,
- unsigned nsecs, unsigned cpol,
+ unsigned nsecs, unsigned cpol, unsigned flags,
u32 word, u8 bits)
{
/* if (cpol == 0) this is SPI_MODE_1; else this is SPI_MODE_3 */
@@ -79,7 +81,8 @@ bitbang_txrx_be_cpha1(struct spi_device *spi,
/* setup MSB (to slave) on leading edge */
setsck(spi, !cpol);
- setmosi(spi, word & (1 << 31));
+ if ((flags & SPI_MASTER_NO_TX) == 0)
+ setmosi(spi, word & (1 << 31));
spidelay(nsecs); /* T(setup) */
setsck(spi, cpol);
@@ -87,7 +90,8 @@ bitbang_txrx_be_cpha1(struct spi_device *spi,
/* sample MSB (from slave) on trailing edge */
word <<= 1;
- word |= getmiso(spi);
+ if ((flags & SPI_MASTER_NO_RX) == 0)
+ word |= getmiso(spi);
}
return word;
}
diff --git a/drivers/spi/spi_butterfly.c b/drivers/spi/spi_butterfly.c
index 8b5281281111..0d4ceba3b590 100644
--- a/drivers/spi/spi_butterfly.c
+++ b/drivers/spi/spi_butterfly.c
@@ -156,7 +156,7 @@ butterfly_txrx_word_mode0(struct spi_device *spi,
unsigned nsecs,
u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
/*----------------------------------------------------------------------*/
diff --git a/drivers/spi/spi_gpio.c b/drivers/spi/spi_gpio.c
index 7edbd5807e0e..e24a63498acb 100644
--- a/drivers/spi/spi_gpio.c
+++ b/drivers/spi/spi_gpio.c
@@ -146,25 +146,63 @@ static inline int getmiso(const struct spi_device *spi)
static u32 spi_gpio_txrx_word_mode0(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
static u32 spi_gpio_txrx_word_mode1(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits);
}
static u32 spi_gpio_txrx_word_mode2(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits);
}
static u32 spi_gpio_txrx_word_mode3(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
+}
+
+/*
+ * These functions do not call setmosi or getmiso if respective flag
+ * (SPI_MASTER_NO_RX or SPI_MASTER_NO_TX) is set, so they are safe to
+ * call when such pin is not present or defined in the controller.
+ * A separate set of callbacks is defined to get highest possible
+ * speed in the generic case (when both MISO and MOSI lines are
+ * available), as optimiser will remove the checks when argument is
+ * constant.
+ */
+
+static u32 spi_gpio_spec_txrx_word_mode0(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ unsigned flags = spi->master->flags;
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, flags, word, bits);
+}
+
+static u32 spi_gpio_spec_txrx_word_mode1(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ unsigned flags = spi->master->flags;
+ return bitbang_txrx_be_cpha1(spi, nsecs, 0, flags, word, bits);
+}
+
+static u32 spi_gpio_spec_txrx_word_mode2(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ unsigned flags = spi->master->flags;
+ return bitbang_txrx_be_cpha0(spi, nsecs, 1, flags, word, bits);
+}
+
+static u32 spi_gpio_spec_txrx_word_mode3(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ unsigned flags = spi->master->flags;
+ return bitbang_txrx_be_cpha1(spi, nsecs, 1, flags, word, bits);
}
/*----------------------------------------------------------------------*/
@@ -232,19 +270,30 @@ static int __init spi_gpio_alloc(unsigned pin, const char *label, bool is_in)
}
static int __init
-spi_gpio_request(struct spi_gpio_platform_data *pdata, const char *label)
+spi_gpio_request(struct spi_gpio_platform_data *pdata, const char *label,
+ u16 *res_flags)
{
int value;
/* NOTE: SPI_*_GPIO symbols may reference "pdata" */
- value = spi_gpio_alloc(SPI_MOSI_GPIO, label, false);
- if (value)
- goto done;
+ if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) {
+ value = spi_gpio_alloc(SPI_MOSI_GPIO, label, false);
+ if (value)
+ goto done;
+ } else {
+ /* HW configuration without MOSI pin */
+ *res_flags |= SPI_MASTER_NO_TX;
+ }
- value = spi_gpio_alloc(SPI_MISO_GPIO, label, true);
- if (value)
- goto free_mosi;
+ if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) {
+ value = spi_gpio_alloc(SPI_MISO_GPIO, label, true);
+ if (value)
+ goto free_mosi;
+ } else {
+ /* HW configuration without MISO pin */
+ *res_flags |= SPI_MASTER_NO_RX;
+ }
value = spi_gpio_alloc(SPI_SCK_GPIO, label, false);
if (value)
@@ -253,9 +302,11 @@ spi_gpio_request(struct spi_gpio_platform_data *pdata, const char *label)
goto done;
free_miso:
- gpio_free(SPI_MISO_GPIO);
+ if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO)
+ gpio_free(SPI_MISO_GPIO);
free_mosi:
- gpio_free(SPI_MOSI_GPIO);
+ if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI)
+ gpio_free(SPI_MOSI_GPIO);
done:
return value;
}
@@ -266,6 +317,7 @@ static int __init spi_gpio_probe(struct platform_device *pdev)
struct spi_master *master;
struct spi_gpio *spi_gpio;
struct spi_gpio_platform_data *pdata;
+ u16 master_flags = 0;
pdata = pdev->dev.platform_data;
#ifdef GENERIC_BITBANG
@@ -273,7 +325,7 @@ static int __init spi_gpio_probe(struct platform_device *pdev)
return -ENODEV;
#endif
- status = spi_gpio_request(pdata, dev_name(&pdev->dev));
+ status = spi_gpio_request(pdata, dev_name(&pdev->dev), &master_flags);
if (status < 0)
return status;
@@ -289,6 +341,7 @@ static int __init spi_gpio_probe(struct platform_device *pdev)
if (pdata)
spi_gpio->pdata = *pdata;
+ master->flags = master_flags;
master->bus_num = pdev->id;
master->num_chipselect = SPI_N_CHIPSEL;
master->setup = spi_gpio_setup;
@@ -296,10 +349,18 @@ static int __init spi_gpio_probe(struct platform_device *pdev)
spi_gpio->bitbang.master = spi_master_get(master);
spi_gpio->bitbang.chipselect = spi_gpio_chipselect;
- spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0;
- spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_txrx_word_mode1;
- spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_txrx_word_mode2;
- spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_txrx_word_mode3;
+
+ if ((master_flags & (SPI_MASTER_NO_RX | SPI_MASTER_NO_RX)) == 0) {
+ spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_txrx_word_mode1;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_txrx_word_mode2;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_txrx_word_mode3;
+ } else {
+ spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_spec_txrx_word_mode0;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_spec_txrx_word_mode1;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_spec_txrx_word_mode2;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_spec_txrx_word_mode3;
+ }
spi_gpio->bitbang.setup_transfer = spi_bitbang_setup_transfer;
spi_gpio->bitbang.flags = SPI_CS_HIGH;
@@ -307,8 +368,10 @@ static int __init spi_gpio_probe(struct platform_device *pdev)
if (status < 0) {
spi_master_put(spi_gpio->bitbang.master);
gpio_free:
- gpio_free(SPI_MISO_GPIO);
- gpio_free(SPI_MOSI_GPIO);
+ if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO)
+ gpio_free(SPI_MISO_GPIO);
+ if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI)
+ gpio_free(SPI_MOSI_GPIO);
gpio_free(SPI_SCK_GPIO);
spi_master_put(master);
}
@@ -331,8 +394,10 @@ static int __exit spi_gpio_remove(struct platform_device *pdev)
platform_set_drvdata(pdev, NULL);
- gpio_free(SPI_MISO_GPIO);
- gpio_free(SPI_MOSI_GPIO);
+ if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO)
+ gpio_free(SPI_MISO_GPIO);
+ if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI)
+ gpio_free(SPI_MOSI_GPIO);
gpio_free(SPI_SCK_GPIO);
return status;
diff --git a/drivers/spi/spi_lm70llp.c b/drivers/spi/spi_lm70llp.c
index 86fb7b5993db..7746a41ab6d6 100644
--- a/drivers/spi/spi_lm70llp.c
+++ b/drivers/spi/spi_lm70llp.c
@@ -191,7 +191,7 @@ static void lm70_chipselect(struct spi_device *spi, int value)
*/
static u32 lm70_txrx(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
static void spi_lm70llp_attach(struct parport *p)
diff --git a/drivers/spi/spi_s3c24xx_gpio.c b/drivers/spi/spi_s3c24xx_gpio.c
index 8979a75dbd7b..be991359bf92 100644
--- a/drivers/spi/spi_s3c24xx_gpio.c
+++ b/drivers/spi/spi_s3c24xx_gpio.c
@@ -64,25 +64,25 @@ static inline u32 getmiso(struct spi_device *dev)
static u32 s3c2410_spigpio_txrx_mode0(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
static u32 s3c2410_spigpio_txrx_mode1(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits);
}
static u32 s3c2410_spigpio_txrx_mode2(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits);
}
static u32 s3c2410_spigpio_txrx_mode3(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
}
diff --git a/drivers/spi/spi_sh_sci.c b/drivers/spi/spi_sh_sci.c
index a511be7961a0..5c6439161199 100644
--- a/drivers/spi/spi_sh_sci.c
+++ b/drivers/spi/spi_sh_sci.c
@@ -83,25 +83,25 @@ static inline u32 getmiso(struct spi_device *dev)
static u32 sh_sci_spi_txrx_mode0(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
static u32 sh_sci_spi_txrx_mode1(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits);
}
static u32 sh_sci_spi_txrx_mode2(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits);
}
static u32 sh_sci_spi_txrx_mode3(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
}
static void sh_sci_spi_chipselect(struct spi_device *dev, int value)
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index af56071b06f9..ae0a5286f558 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -262,6 +262,13 @@ struct spi_master {
#define SPI_MASTER_NO_RX BIT(1) /* can't do buffer read */
#define SPI_MASTER_NO_TX BIT(2) /* can't do buffer write */
+ /* lock and mutex for SPI bus locking */
+ spinlock_t bus_lock_spinlock;
+ struct mutex bus_lock_mutex;
+
+ /* flag indicating that the SPI bus is locked for exclusive use */
+ bool bus_lock_flag;
+
/* Setup mode and clock, etc (spi driver may call many times).
*
* IMPORTANT: this may be called when transfers to another
@@ -542,6 +549,8 @@ static inline void spi_message_free(struct spi_message *m)
extern int spi_setup(struct spi_device *spi);
extern int spi_async(struct spi_device *spi, struct spi_message *message);
+extern int spi_async_locked(struct spi_device *spi,
+ struct spi_message *message);
/*---------------------------------------------------------------------------*/
@@ -551,6 +560,9 @@ extern int spi_async(struct spi_device *spi, struct spi_message *message);
*/
extern int spi_sync(struct spi_device *spi, struct spi_message *message);
+extern int spi_sync_locked(struct spi_device *spi, struct spi_message *message);
+extern int spi_bus_lock(struct spi_master *master);
+extern int spi_bus_unlock(struct spi_master *master);
/**
* spi_write - SPI synchronous write
diff --git a/include/linux/spi/spi_gpio.h b/include/linux/spi/spi_gpio.h
index ca6782ee4b9f..369b3d7d5b95 100644
--- a/include/linux/spi/spi_gpio.h
+++ b/include/linux/spi/spi_gpio.h
@@ -29,11 +29,16 @@
* SPI_GPIO_NO_CHIPSELECT to the controller_data:
* .controller_data = (void *) SPI_GPIO_NO_CHIPSELECT;
*
+ * If the MISO or MOSI pin is not available then it should be set to
+ * SPI_GPIO_NO_MISO or SPI_GPIO_NO_MOSI.
+ *
* If the bitbanged bus is later switched to a "native" controller,
* that platform_device and controller_data should be removed.
*/
#define SPI_GPIO_NO_CHIPSELECT ((unsigned long)-1l)
+#define SPI_GPIO_NO_MISO ((unsigned long)-1l)
+#define SPI_GPIO_NO_MOSI ((unsigned long)-1l)
/**
* struct spi_gpio_platform_data - parameter for bitbanged SPI master