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| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2023-04-01 19:59:47 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2023-04-05 12:33:33 +0100 |
| commit | 8a5299a1278eadf1e08a598a5345c376206f171e (patch) | |
| tree | 28c5bdd4741a1945b96f485c9c07592782b6280c /drivers/spi | |
| parent | c20c57d9868d7f9fd1b2904c7801b07e128f6322 (diff) | |
| download | linux-8a5299a1278eadf1e08a598a5345c376206f171e.tar.gz linux-8a5299a1278eadf1e08a598a5345c376206f171e.tar.bz2 linux-8a5299a1278eadf1e08a598a5345c376206f171e.zip | |
spi: fsl-spi: Re-organise transfer bits_per_word adaptation
For different reasons, fsl-spi driver performs bits_per_word
modifications for different reasons:
- On CPU mode, to minimise amount of interrupts
- On CPM/QE mode to work around controller byte order
For CPU mode that's done in fsl_spi_prepare_message() while
for CPM mode that's done in fsl_spi_setup_transfer().
Reunify all of it in fsl_spi_prepare_message(), and catch
impossible cases early through master's bits_per_word_mask
instead of returning EINVAL later.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/0ce96fe96e8b07cba0613e4097cfd94d09b8919a.1680371809.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-fsl-spi.c | 46 |
1 files changed, 21 insertions, 25 deletions
diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c index 4651f65c9046..194b6611dab6 100644 --- a/drivers/spi/spi-fsl-spi.c +++ b/drivers/spi/spi-fsl-spi.c @@ -177,26 +177,6 @@ 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) -{ - /* 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 (spi->mode & SPI_LSB_FIRST && - bits_per_word > 8) - return -EINVAL; - if (bits_per_word <= 8) - return bits_per_word; - if (bits_per_word == 16 || bits_per_word == 32) - return 8; /* pretend its 8 bits */ - return -EINVAL; -} - static int fsl_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) { @@ -224,9 +204,6 @@ 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 - bits_per_word = mspi_apply_qe_mode_quirks(cs, spi, - bits_per_word); if (bits_per_word < 0) return bits_per_word; @@ -361,6 +338,19 @@ static int fsl_spi_prepare_message(struct spi_controller *ctlr, 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 */ } } return fsl_spi_setup_transfer(m->spi, first); @@ -594,8 +584,14 @@ 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) |