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authorMark Brown <broonie@kernel.org>2020-02-28 18:17:19 +0000
committerMark Brown <broonie@kernel.org>2020-02-28 18:17:19 +0000
commit6c4a3372f03b3b66ca755fc6a6e72c577817ec5f (patch)
treef6dbc5ab3961d1a439a22e147efe45b7e5254536 /include/linux
parentc0e035ac56680e74b27fc218c07e70f4b9b8b7a5 (diff)
parent34e608b023e96f51b31274435b49c8ae61e2389f (diff)
Merge series "spi/HiSilicon v3xx: Support dual and quad mode through DMI quirks" from John Garry <john.garry@huawei.com>:
As discussed during the original HiSilicon v3xx SPI driver upstreaming, currently there is no method for the ACPI SPI Serial Bus Connection Resource Descriptor to define the data buswidth [0], [1]. So we can look to get the ACPI spec updated for this, and I have submitted a proposal for a new feature here: https://bugzilla.tianocore.org/show_bug.cgi?id=2557 However I am not sure how successful that will be. In the meantime, as an alternate approach, this RFC proposes to allow the SPI controller driver override the device buswidth. In this example, the driver uses DMI quirks to discover the host machine and set the buswidth override accordingly when the machine is known to support dual or quad mode of operation. I also have included a fix for dual and quad modes in the driver. Comments welcome. thanks. [0] https://lore.kernel.org/linux-mtd/20200109212842.GK3702@sirena.org.uk/ [1] https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf, 19.6.126 John Garry (3): spi: Allow SPI controller override device buswidth spi: HiSilicon v3xx: Properly set CMD_CONFIG for Dual/Quad modes spi: HiSilicon v3xx: Use DMI quirk to set controller buswidth override bits drivers/spi/spi-hisi-sfc-v3xx.c | 99 ++++++++++++++++++++++++++++++++- drivers/spi/spi.c | 4 +- include/linux/spi/spi.h | 3 + 3 files changed, 104 insertions(+), 2 deletions(-) -- 2.17.1 ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/spi/spi.h3
1 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 6d16ba01ff5a..600e3793303e 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -481,6 +481,9 @@ struct spi_controller {
/* spi_device.mode flags understood by this controller driver */
u32 mode_bits;
+ /* spi_device.mode flags override flags for this controller */
+ u32 buswidth_override_bits;
+
/* bitmask of supported bits_per_word for transfers */
u32 bits_per_word_mask;
#define SPI_BPW_MASK(bits) BIT((bits) - 1)