At the end of a message, the HW gets a reset in meson_spicc_unprepare_transfer(),
this resets the SPICC_CONREG register and notably the value set by the
Common Clock Framework.
This is problematic because:
- the register value CCF can be different from the corresponding CCF cached rate
- CCF is allowed to change the clock rate whenever the HW state
This introduces:
- local pow2 clock ops checking the HW state before allowing a clock operation
- separation of legacy pow2 clock patch and new enhanced clock path
- SPICC_CONREG datarate value is now value kepts across messages
It has been checked that:
- SPICC_CONREG datarate value is kept across messages
- CCF is only allowed to change the SPICC_CONREG datarate value when busy
- SPICC_CONREG datarate value is correct for each transfer
This didn't appear before commit 3e0cf4d3fc ("spi: meson-spicc: add a linear clock divider support")
because we recalculated and wrote the rate for each xfer.
Fixes: 3e0cf4d3fc ("spi: meson-spicc: add a linear clock divider support")
Reported-by: Da Xue <da@libre.computer>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20220811134445.678446-1-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This check misses checking for platform_get_irq()'s call and may passes
the negative error codes to devm_request_irq(), which takes unsigned IRQ #,
causing it to fail with -EINVAL, overriding an original error code.
Stop calling devm_request_irq() with invalid IRQ #s.
Fixes: 454fa271bc ("spi: Add Meson SPICC driver")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220126110447.24549-1-linmq006@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
If devm_spi_register_master() fails in meson_spicc_probe(),
spicc->core is left undisabled. The patch fixes that.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add new compatible string to support SPICC controller which
found at Amlogic Meson-AXG SoC. This is aiming at adding
a couple of enhanced feature patches.
Signed-off-by: Sunny Luo <sunny.luo@amlogic.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The SPICC hardware block on the Amlogic SoCs is Communication oriented and
can do Full-Duplex 8- to 32-bit width SPI transfers up to 30MHz.
The current driver only supportd the PIO transfer mode since the DMA seems
broken on available hardware.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
