[PATCH v2 2/2] spi/spi-bcm2835: Add bcm2835_spi_transfer_one_message in spi-bcm2835.c
Meghana Madhyastha
meghana.madhyastha at gmail.com
Sat Feb 24 18:17:12 UTC 2018
Add bcm2835_spi_transfer_one_message in spi-bcm2835.c. This function calls
the helper spi_split_transfers_maxsize before calling spi_transfer_one_message
to split the message into smaller chunks to be able to use dma.
Signed-off-by: Meghana Madhyastha <meghana.madhyastha at gmail.com>
---
drivers/spi/spi-bcm2835.c | 14 ++++++++++++++
drivers/spi/spi.c | 5 ++---
include/linux/spi/spi.h | 2 ++
3 files changed, 18 insertions(+), 3 deletions(-)
diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c
index 2fd650891c07..68d35407e7a3 100644
--- a/drivers/spi/spi-bcm2835.c
+++ b/drivers/spi/spi-bcm2835.c
@@ -579,6 +579,19 @@ static int bcm2835_spi_transfer_one(struct spi_master *master,
return bcm2835_spi_transfer_one_irq(master, spi, tfr, cs);
}
+static int bcm2835_spi_transfer_one_message(struct spi_controller *ctlr,
+ struct spi_message *msg)
+{
+ int ret;
+ gfp_t gfp_flags = GFP_KERNEL | GFP_DMA;
+ size_t max_transfer_size = 64;
+ ret = spi_split_transfers_maxsize(ctlr, msg, max_transfer_size, gfp_flags);
+ if (ret)
+ return ret;
+
+ return spi_transfer_one_message(ctlr, msg);
+}
+
static int bcm2835_spi_prepare_message(struct spi_master *master,
struct spi_message *msg)
{
@@ -739,6 +752,7 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
master->setup = bcm2835_spi_setup;
master->set_cs = bcm2835_spi_set_cs;
master->transfer_one = bcm2835_spi_transfer_one;
+ master->transfer_one_message = bcm2835_spi_transfer_one_message;
master->handle_err = bcm2835_spi_handle_err;
master->prepare_message = bcm2835_spi_prepare_message;
master->dev.of_node = pdev->dev.of_node;
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index b33a727a0158..3a352a0a6cdf 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1003,7 +1003,7 @@ static int spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
* drivers which implement a transfer_one() operation. It provides
* standard handling of delays and chip select management.
*/
-static int spi_transfer_one_message(struct spi_controller *ctlr,
+int spi_transfer_one_message(struct spi_controller *ctlr,
struct spi_message *msg)
{
struct spi_transfer *xfer;
@@ -1026,7 +1026,6 @@ static int spi_transfer_one_message(struct spi_controller *ctlr,
if (xfer->tx_buf || xfer->rx_buf) {
reinit_completion(&ctlr->xfer_completion);
-
ret = ctlr->transfer_one(ctlr, msg->spi, xfer);
if (ret < 0) {
SPI_STATISTICS_INCREMENT_FIELD(statm,
@@ -1111,6 +1110,7 @@ static int spi_transfer_one_message(struct spi_controller *ctlr,
return ret;
}
+EXPORT_SYMBOL_GPL(spi_transfer_one_message);
/**
* spi_finalize_current_transfer - report completion of a transfer
@@ -2583,7 +2583,6 @@ static int __spi_split_transfer_maxsize(struct spi_controller *ctlr,
/* calculate how many we have to replace */
count = DIV_ROUND_UP(xfer->len, maxsize);
-
/* create replacement */
srt = spi_replace_transfers(msg, xfer, 1, count, NULL, 0, gfp);
if (IS_ERR(srt))
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index bc6bb325d1bf..49b6dbce3e6d 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -622,6 +622,8 @@ extern void spi_finalize_current_transfer(struct spi_controller *ctlr);
/* the spi driver core manages memory for the spi_controller classdev */
extern struct spi_controller *__spi_alloc_controller(struct device *host,
unsigned int size, bool slave);
+extern int spi_transfer_one_message(struct spi_controller *ctlr,
+ struct spi_message *msg);
static inline struct spi_controller *spi_alloc_master(struct device *host,
unsigned int size)
--
2.11.0
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