ee9780d7e7
[ Upstream commit 0196c8db8363f7627df6f78615271ae0ba430500 ]
tmio_mmc_set_clock() is full of quirks because different SoC vendors
extended this in different ways.
The original IP defines the divisor range 1/2 ... 1/512.
bit 7 is set: 1/512
bit 6 is set: 1/256
...
bit 0 is set: 1/4
all bits clear: 1/2
It is platform-dependent how to achieve the 1/1 clock.
I guess the TMIO-MFD variant uses the clock selector outside of this IP,
as far as I see tmio_core_mmc_clk_div() in drivers/mfd/tmio_core.c
I guess bit[7:0]=0xff is Renesas-specific extension.
Socionext (and Panasonic) uses bit 10 (CLKSEL) for 1/1. Also, newer
versions of UniPhier SoC variants use bit 16 for 1/1024.
host->clk_update() is only used by the Renesas variants, whereas
host->set_clk_div() is only used by the TMIO-MFD variants.
To cope with this mess, promote tmio_mmc_set_clock() to a new
platform hook ->set_clock(), and melt the old two hooks into it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Stable-dep-of: 71150ac12558 ("mmc: bcm2835: fix deferred probing")
Signed-off-by: Sasha Levin <sashal@kernel.org>
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