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path: root/drivers/spi/spi-fsl-spi.c
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-rw-r--r--drivers/spi/spi-fsl-spi.c63
1 files changed, 40 insertions, 23 deletions
diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c
index cd784552d..5e49fed48 100644
--- a/drivers/spi/spi-fsl-spi.c
+++ b/drivers/spi/spi-fsl-spi.c
@@ -201,24 +201,6 @@ static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
return bits_per_word;
}
-static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
- struct spi_device *spi,
- int bits_per_word)
-{
- /* QE uses Little Endian for words > 8
- * so transform all words > 8 into 8 bits
- * Unfortnatly that doesn't work for LSB so
- * reject these for now */
- /* Note: 32 bits word, LSB works iff
- * tfcr/rfcr is set to CPMFCR_GBL */
- if (spi->mode & SPI_LSB_FIRST &&
- bits_per_word > 8)
- return -EINVAL;
- if (bits_per_word > 8)
- return 8; /* pretend its 8 bits */
- return bits_per_word;
-}
-
static int fsl_spi_setup_transfer(struct spi_device *spi,
struct spi_transfer *t)
{
@@ -246,9 +228,6 @@ static int fsl_spi_setup_transfer(struct spi_device *spi,
bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
mpc8xxx_spi,
bits_per_word);
- else if (mpc8xxx_spi->flags & SPI_QE)
- bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
- bits_per_word);
if (bits_per_word < 0)
return bits_per_word;
@@ -355,12 +334,44 @@ static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
static int fsl_spi_do_one_msg(struct spi_master *master,
struct spi_message *m)
{
+ struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
struct spi_device *spi = m->spi;
struct spi_transfer *t, *first;
unsigned int cs_change;
const int nsecs = 50;
int status;
+ /*
+ * In CPU mode, optimize large byte transfers to use larger
+ * bits_per_word values to reduce number of interrupts taken.
+ */
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) {
+ if (t->len < 256 || t->bits_per_word != 8)
+ continue;
+ if ((t->len & 3) == 0)
+ t->bits_per_word = 32;
+ else if ((t->len & 1) == 0)
+ t->bits_per_word = 16;
+ } else {
+ /*
+ * CPM/QE uses Little Endian for words > 8
+ * so transform 16 and 32 bits words into 8 bits
+ * Unfortnatly that doesn't work for LSB so
+ * reject these for now
+ * Note: 32 bits word, LSB works iff
+ * tfcr/rfcr is set to CPMFCR_GBL
+ */
+ if (m->spi->mode & SPI_LSB_FIRST && t->bits_per_word > 8)
+ return -EINVAL;
+ if (t->bits_per_word == 16 || t->bits_per_word == 32)
+ t->bits_per_word = 8; /* pretend its 8 bits */
+ if (t->bits_per_word == 8 && t->len >= 256 &&
+ (mpc8xxx_spi->flags & SPI_CPM1))
+ t->bits_per_word = 16;
+ }
+ }
+
/* Don't allow changes if CS is active */
first = list_first_entry(&m->transfers, struct spi_transfer,
transfer_list);
@@ -640,8 +651,14 @@ static struct spi_master * fsl_spi_probe(struct device *dev,
if (mpc8xxx_spi->type == TYPE_GRLIB)
fsl_spi_grlib_probe(dev);
- master->bits_per_word_mask =
- (SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) &
+ if (mpc8xxx_spi->flags & SPI_CPM_MODE)
+ master->bits_per_word_mask =
+ (SPI_BPW_RANGE_MASK(4, 8) | SPI_BPW_MASK(16) | SPI_BPW_MASK(32));
+ else
+ master->bits_per_word_mask =
+ (SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32));
+
+ master->bits_per_word_mask &=
SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word);
if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)