Re: [PATCH 05/10] mmc: spi: Pull out the SSP clock configuration function

[Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>]

Dear Attila Kinali,

> On Mon, 16 Jul 2012 14:09:52 +0200
> 
> Marek Vasut <marex-ynQEQJNshbs@public.gmane.org> wrote:
> > Pull out the MMC clock configuration function and make it
> > into SSP clock configuration function, so it can be used by
> > the SPI driver too.
> > 
> > diff --git a/drivers/clk/mxs/clk-ssp.c b/drivers/clk/mxs/clk-ssp.c
> > new file mode 100644
> > index 0000000..b3c1e16
> > --- /dev/null
> > +++ b/drivers/clk/mxs/clk-ssp.c
> > @@ -0,0 +1,61 @@
> > +/*
> > + * Copyright 2012 DENX Software Engineering, GmbH
> > + *
> > + * Pulled from code:
> > + * Portions copyright (C) 2003 Russell King, PXA MMCI Driver
> > + * Portions copyright (C) 2004-2005 Pierre Ossman, W83L51xD SD/MMC
> > driver + *
> > + * Copyright 2008 Embedded Alley Solutions, Inc.
> > + * Copyright 2009-2011 Freescale Semiconductor, Inc.
> > + *
> > + * The code contained herein is licensed under the GNU General Public
> > + * License. You may obtain a copy of the GNU General Public License
> > + * Version 2 or later at the following locations:
> > + *
> > + * http://www.opensource.org/licenses/gpl-license.html
> > + * http://www.gnu.org/copyleft/gpl.html
> > + */
> > +
> > +#include <linux/kernel.h>
> > +#include <linux/init.h>
> > +#include <linux/clk.h>
> > +#include <linux/module.h>
> > +#include <linux/device.h>
> > +#include <linux/io.h>
> > +#include <linux/spi/mxs-spi.h>
> > +
> > +void mxs_ssp_set_clk_rate(struct mxs_ssp *ssp, unsigned int rate)
> > +{
> > +	unsigned int ssp_clk, ssp_sck;
> > +	u32 clock_divide, clock_rate;
> > +	u32 val;
> > +
> > +	ssp_clk = clk_get_rate(ssp->clk);
> > +
> > +	for (clock_divide = 2; clock_divide <= 254; clock_divide += 2) {
> > +		clock_rate = DIV_ROUND_UP(ssp_clk, rate * clock_divide);
> > +		clock_rate = (clock_rate > 0) ? clock_rate - 1 : 0;
> > +		if (clock_rate <= 255)
> > +			break;
> > +	}
> > +
> > +	if (clock_divide > 254) {
> > +		dev_err(ssp->dev,
> > +			"%s: cannot set clock to %d\n", __func__, rate);
> > +		return;
> > +	}
> > +
> > +	ssp_sck = ssp_clk / clock_divide / (1 + clock_rate);
> > +
> > +	val = readl(ssp->base + HW_SSP_TIMING(ssp));
> > +	val &= ~(BM_SSP_TIMING_CLOCK_DIVIDE | BM_SSP_TIMING_CLOCK_RATE);
> > +	val |= BF_SSP(clock_divide, TIMING_CLOCK_DIVIDE);
> > +	val |= BF_SSP(clock_rate, TIMING_CLOCK_RATE);
> > +	writel(val, ssp->base + HW_SSP_TIMING(ssp));
> > +
> > +	ssp->clk_rate = ssp_sck;
> > +
> > +	dev_dbg(ssp->dev,
> > +		"%s: clock_divide %d, clock_rate %d, ssp_clk %d, rate_actual %d,
> > rate_requested %d\n", +		__func__, clock_divide, clock_rate, 
ssp_clk,
> > ssp_sck, rate);
> > +}
> 
> There is a EXPORT_SYMBOL_GPL(mxs_ssp_set_clk_rate); missing here.

What for?

Best regards,
Marek Vasut

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