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-rw-r--r--drivers/spi/spi-atmel.c26
-rw-r--r--drivers/spi/spi.c24
2 files changed, 46 insertions, 4 deletions
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 3ed5e663da6f..1471b049f99a 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -1149,12 +1149,31 @@ atmel_spi_pdc_interrupt(int irq, void *dev_id)
return ret;
}
+static int atmel_word_delay_csr(struct spi_device *spi, struct atmel_spi *as)
+{
+ struct spi_delay *delay = &spi->word_delay;
+ u32 value = delay->value;
+
+ switch (delay->unit) {
+ case SPI_DELAY_UNIT_NSECS:
+ value /= 1000;
+ break;
+ case SPI_DELAY_UNIT_USECS:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return (as->spi_clk / 1000000 * value) >> 5;
+}
+
static int atmel_spi_setup(struct spi_device *spi)
{
struct atmel_spi *as;
struct atmel_spi_device *asd;
u32 csr;
unsigned int bits = spi->bits_per_word;
+ int word_delay_csr;
as = spi_master_get_devdata(spi->master);
@@ -1178,11 +1197,14 @@ static int atmel_spi_setup(struct spi_device *spi)
*/
csr |= SPI_BF(DLYBS, 0);
+ word_delay_csr = atmel_word_delay_csr(spi, as);
+ if (word_delay_csr < 0)
+ return word_delay_csr;
+
/* DLYBCT adds delays between words. This is useful for slow devices
* that need a bit of time to setup the next transfer.
*/
- csr |= SPI_BF(DLYBCT,
- (as->spi_clk / 1000000 * spi->word_delay_usecs) >> 5);
+ csr |= SPI_BF(DLYBCT, word_delay_csr);
asd = spi->controller_state;
if (!asd) {
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index b69c14082c52..307e440dd92d 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -3281,6 +3281,26 @@ void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold,
}
EXPORT_SYMBOL_GPL(spi_set_cs_timing);
+static int _spi_xfer_word_delay_update(struct spi_transfer *xfer,
+ struct spi_device *spi)
+{
+ int delay1, delay2;
+
+ delay1 = _spi_delay_to_ns(&xfer->word_delay, xfer);
+ if (delay1 < 0)
+ return delay1;
+
+ delay2 = _spi_delay_to_ns(&spi->word_delay, xfer);
+ if (delay2 < 0)
+ return delay2;
+
+ if (delay1 < delay2)
+ memcpy(&xfer->word_delay, &spi->word_delay,
+ sizeof(xfer->word_delay));
+
+ return 0;
+}
+
static int __spi_validate(struct spi_device *spi, struct spi_message *message)
{
struct spi_controller *ctlr = spi->controller;
@@ -3416,8 +3436,8 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
return -EINVAL;
}
- if (xfer->word_delay_usecs < spi->word_delay_usecs)
- xfer->word_delay_usecs = spi->word_delay_usecs;
+ if (_spi_xfer_word_delay_update(xfer, spi))
+ return -EINVAL;
}
message->status = -EINPROGRESS;