[v2 PATCH 06/14] spi/atmel_spi: add flag to controller data for lock operations

From: Wenyou Yang
Date: Tue Dec 04 2012 - 02:58:52 EST


From: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>

Will allow to drop the lock during DMA operations.

Signed-off-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
Cc: grant.likely@xxxxxxxxxxxx
Cc: spi-devel-general@xxxxxxxxxxxxxxxxxxxxx
---
drivers/spi/spi-atmel.c | 31 +++++++++++++++++++------------
1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 76a1baf..37f54c3 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -187,6 +187,7 @@
*/
struct atmel_spi {
spinlock_t lock;
+ unsigned long flags;

resource_size_t phybase;
void __iomem *regs;
@@ -323,6 +324,16 @@ static void cs_deactivate(struct atmel_spi *as, struct spi_device *spi)
gpio_set_value(asd->npcs_pin, !active);
}

+static void atmel_spi_lock(struct atmel_spi *as)
+{
+ spin_lock_irqsave(&as->lock, as->flags);
+}
+
+static void atmel_spi_unlock(struct atmel_spi *as)
+{
+ spin_unlock_irqrestore(&as->lock, as->flags);
+}
+
static inline int atmel_spi_xfer_is_last(struct spi_message *msg,
struct spi_transfer *xfer)
{
@@ -559,9 +570,9 @@ atmel_spi_msg_done(struct spi_master *master, struct atmel_spi *as,
"xfer complete: %u bytes transferred\n",
msg->actual_length);

- spin_unlock(&as->lock);
+ atmel_spi_unlock(as);
msg->complete(msg->context);
- spin_lock(&as->lock);
+ atmel_spi_lock(as);

as->current_transfer = NULL;
as->next_transfer = NULL;
@@ -788,13 +799,11 @@ static int atmel_spi_setup(struct spi_device *spi)
spi->controller_state = asd;
gpio_direction_output(npcs_pin, !(spi->mode & SPI_CS_HIGH));
} else {
- unsigned long flags;
-
- spin_lock_irqsave(&as->lock, flags);
+ atmel_spi_lock(as);
if (as->stay == spi)
as->stay = NULL;
cs_deactivate(as, spi);
- spin_unlock_irqrestore(&as->lock, flags);
+ atmel_spi_unlock(as);
}

asd->csr = csr;
@@ -813,7 +822,6 @@ static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg)
{
struct atmel_spi *as;
struct spi_transfer *xfer;
- unsigned long flags;
struct device *controller = spi->master->dev.parent;
u8 bits;
struct atmel_spi_device *asd;
@@ -878,11 +886,11 @@ static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg)
msg->status = -EINPROGRESS;
msg->actual_length = 0;

- spin_lock_irqsave(&as->lock, flags);
+ atmel_spi_lock(as);
list_add_tail(&msg->queue, &as->queue);
if (!as->current_transfer)
atmel_spi_next_message(spi->master);
- spin_unlock_irqrestore(&as->lock, flags);
+ atmel_spi_unlock(as);

return 0;
}
@@ -892,17 +900,16 @@ static void atmel_spi_cleanup(struct spi_device *spi)
struct atmel_spi *as = spi_master_get_devdata(spi->master);
struct atmel_spi_device *asd = spi->controller_state;
unsigned gpio = (unsigned) spi->controller_data;
- unsigned long flags;

if (!asd)
return;

- spin_lock_irqsave(&as->lock, flags);
+ atmel_spi_lock(as);
if (as->stay == spi) {
as->stay = NULL;
cs_deactivate(as, spi);
}
- spin_unlock_irqrestore(&as->lock, flags);
+ atmel_spi_unlock(as);

spi->controller_state = NULL;
gpio_free(gpio);
--
1.7.9.5

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