diff options
| author | Luca Ceresoli <luca.ceresoli@bootlin.com> | 2022-04-22 00:32:51 +0300 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2022-04-25 16:01:01 +0300 |
| commit | d5d933f09ac326aebad85bfb787cc786ad477711 (patch) | |
| tree | 5540847d65f8467d2a8d741dea18b4bcecba33bb /drivers/spi | |
| parent | 40b6a137717bb5ca5ccb4e4b051e0d22019cd188 (diff) | |
| download | linux-d5d933f09ac326aebad85bfb787cc786ad477711.tar.xz | |
spi: rockchip: fix missing error on unsupported SPI_CS_HIGH
The hardware (except for the ROCKCHIP_SPI_VER2_TYPE2 version) does not
support active-high native chip selects. However if such a CS is configured
the core does not error as it normally should, because the
'ctlr->use_gpio_descriptors = true' line in rockchip_spi_probe() makes the
core set SPI_CS_HIGH in ctlr->mode_bits.
In such a case the spi-rockchip driver operates normally but produces an
active-low chip select signal without notice.
There is no provision in the current core code to handle this
situation. Fix by adding a check in the ctlr->setup function (similarly to
what spi-atmel.c does).
This cannot be done reading the SPI_CS_HIGH but in ctlr->mode_bits because
that bit gets always set by the core for master mode (see above).
Fixes: eb1262e3cc8b ("spi: spi-rockchip: use num-cs property and ctlr->enable_gpiods")
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Link: https://lore.kernel.org/r/20220421213251.1077899-1-luca.ceresoli@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-rockchip.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index cdc16eecaf6b..a08215eb9e14 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -196,6 +196,8 @@ struct rockchip_spi { bool slave_abort; bool cs_inactive; /* spi slave tansmition stop when cs inactive */ + bool cs_high_supported; /* native CS supports active-high polarity */ + struct spi_transfer *xfer; /* Store xfer temporarily */ }; @@ -719,6 +721,11 @@ static int rockchip_spi_setup(struct spi_device *spi) struct rockchip_spi *rs = spi_controller_get_devdata(spi->controller); u32 cr0; + if (!spi->cs_gpiod && (spi->mode & SPI_CS_HIGH) && !rs->cs_high_supported) { + dev_warn(&spi->dev, "setup: non GPIO CS can't be active-high\n"); + return -EINVAL; + } + pm_runtime_get_sync(rs->dev); cr0 = readl_relaxed(rs->regs + ROCKCHIP_SPI_CTRLR0); @@ -899,6 +906,7 @@ static int rockchip_spi_probe(struct platform_device *pdev) switch (readl_relaxed(rs->regs + ROCKCHIP_SPI_VERSION)) { case ROCKCHIP_SPI_VER2_TYPE2: + rs->cs_high_supported = true; ctlr->mode_bits |= SPI_CS_HIGH; if (ctlr->can_dma && slave_mode) rs->cs_inactive = true; |