Commit 69daf75a authored by Boris Brezillon's avatar Boris Brezillon Committed by Michael Turquette
Browse files

clk: at91: usb: fix at91sam9x5 recalc, round and set rate 



First check for rate == 0 in set_rate and round_rate to avoid div by zero.
Then, in order to get the closest rate, round all divisions to the closest
result instead of rounding them down.

Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: default avatarNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: default avatarMichael Turquette <mturquette@linaro.org>
parent ff553ea1

drivers/clk/at91/clk-usb.c

+15 −14
Original line number Diff line number Diff line
@@ -52,29 +52,26 @@ static unsigned long at91sam9x5_clk_usb_recalc_rate(struct clk_hw *hw, 


	tmp = pmc_read(pmc, AT91_PMC_USB);

	usbdiv = (tmp & AT91_PMC_OHCIUSBDIV) >> SAM9X5_USB_DIV_SHIFT;

	return parent_rate / (usbdiv + 1);



	return DIV_ROUND_CLOSEST(parent_rate, (usbdiv + 1));

}



static long at91sam9x5_clk_usb_round_rate(struct clk_hw *hw, unsigned long rate,

					  unsigned long *parent_rate)

{

	unsigned long div;

	unsigned long bestrate;

	unsigned long tmp;



	if (!rate)

		return -EINVAL;



	if (rate >= *parent_rate)

		return *parent_rate;



	div = *parent_rate / rate;

	if (div >= SAM9X5_USB_MAX_DIV)

		return *parent_rate / (SAM9X5_USB_MAX_DIV + 1);



	bestrate = *parent_rate / div;

	tmp = *parent_rate / (div + 1);

	if (bestrate - rate > rate - tmp)

		bestrate = tmp;

	div = DIV_ROUND_CLOSEST(*parent_rate, rate);

	if (div > SAM9X5_USB_MAX_DIV + 1)

		div = SAM9X5_USB_MAX_DIV + 1;



	return bestrate;

	return DIV_ROUND_CLOSEST(*parent_rate, div);

}



static int at91sam9x5_clk_usb_set_parent(struct clk_hw *hw, u8 index)
@@ -106,9 +103,13 @@ static int at91sam9x5_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate, 
	u32 tmp;

	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);

	struct at91_pmc *pmc = usb->pmc;

	unsigned long div = parent_rate / rate;

	unsigned long div;



	if (parent_rate % rate || div < 1 || div >= SAM9X5_USB_MAX_DIV)

	if (!rate)

		return -EINVAL;



	div = DIV_ROUND_CLOSEST(parent_rate, rate);

	if (div > SAM9X5_USB_MAX_DIV + 1 || !div)

		return -EINVAL;



	tmp = pmc_read(pmc, AT91_PMC_USB) & ~AT91_PMC_OHCIUSBDIV;

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