clk: bcm2835: Clamp the PLL's requested rate to the hardware limits.

Fixes setting low-resolution video modes on HDMI. Now the PLLH_PIX
divider adjusts itself until the PLLH is within bounds.

Signed-off-by: Eric Anholt <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>

drivers/clk/bcm/clk-bcm2835.c

···
 static long bcm2835_pll_round_rate(struct clk_hw *hw, unsigned long rate,
 				   unsigned long *parent_rate)
 {
+	struct bcm2835_pll *pll = container_of(hw, struct bcm2835_pll, hw);
+	const struct bcm2835_pll_data *data = pll->data;
 	u32 ndiv, fdiv;
+
+	rate = clamp(rate, data->min_rate, data->max_rate);
 
 	bcm2835_pll_choose_ndiv_and_fdiv(rate, *parent_rate, &ndiv, &fdiv);
 
···
 	u32 ndiv, fdiv, a2w_ctl;
 	u32 ana[4];
 	int i;
-
-	if (rate < data->min_rate || rate > data->max_rate) {
-		dev_err(cprman->dev, "%s: rate out of spec: %lu vs (%lu, %lu)\n",
-			clk_hw_get_name(hw), rate,
-			data->min_rate, data->max_rate);
-		return -EINVAL;
-	}
 
 	if (rate > data->max_fb_rate) {
 		use_fb_prediv = true;