spi: pxa2xx: choose closest lower speed (3ad48062) · Commits · 戴 / test

As per discussion [1] the best choice is to set closest speed which is not going over the asked one. Do the same approach for Intel Quark boards. [1] http://www.spinics.net/lists/linux-spi/msg03389.html Signed-off-by:

Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by:

Mark Brown <broonie@kernel.org>

drivers/spi/spi-pxa2xx.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -730,7 +730,7 @@ static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
		mul = (1 << 24) >> 1;

		/* Calculate initial quot */
		q1 = DIV_ROUND_CLOSEST(fref1, rate);
		q1 = DIV_ROUND_UP(fref1, rate);

		/* Scale q1 if it's too big */
		if (q1 > 256) {
		@@ -755,7 +755,7 @@ static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)

		/* Case 2 */

		q2 = DIV_ROUND_CLOSEST(fref2, rate);
		q2 = DIV_ROUND_UP(fref2, rate);
		r2 = abs(fref2 / q2 - rate);

		/*
		@@ -774,13 +774,13 @@ static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
		mul = (1 << 24) * 2 / 5;
		}

		/* Check case 3 only If the divisor is big enough */
		/* Check case 3 only if the divisor is big enough */
		if (fref / rate >= 80) {
		u64 fssp;
		u32 m;

		/* Calculate initial quot */
		q1 = DIV_ROUND_CLOSEST(fref, rate);
		q1 = DIV_ROUND_UP(fref, rate);
		m = (1 << 24) / q1;

		/* Get the remainder */

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