media: ccs-pll: Add support for extended input PLL clock divider

CCS allows odd PLL dividers other than 1, granted that the corresponding
capability bit is set. Support this both in the PLL calculator and the CCS
driver.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/i2c/ccs-pll.c

@@ -478,7 +478,9 @@ int ccs_pll_calculate(struct device *dev, const struct ccs_pll_limits *lim,
 
 	for (op_pll_fr->pre_pll_clk_div = min_op_pre_pll_clk_div;
 	     op_pll_fr->pre_pll_clk_div <= max_op_pre_pll_clk_div;
-	     op_pll_fr->pre_pll_clk_div += 2 - (op_pll_fr->pre_pll_clk_div & 1)) {
+	     op_pll_fr->pre_pll_clk_div +=
+		     (pll->flags & CCS_PLL_FLAG_EXT_IP_PLL_DIVIDER) ? 1 :
+		     2 - (op_pll_fr->pre_pll_clk_div & 1)) {
 		rval = __ccs_pll_calculate(dev, lim, op_lim_fr, op_lim_bk, pll,
 					   op_pll_fr, op_pll_bk, mul, div);
 		if (rval)

drivers/media/i2c/ccs-pll.h

@@ -25,6 +25,7 @@
 /* CCS PLL flags */
 #define CCS_PLL_FLAG_LANE_SPEED_MODEL				BIT(2)
 #define CCS_PLL_FLAG_LINK_DECOUPLED				BIT(3)
+#define CCS_PLL_FLAG_EXT_IP_PLL_DIVIDER				BIT(4)
 
 /**
  * struct ccs_pll_branch_fr - CCS PLL configuration (front)

drivers/media/i2c/ccs/ccs-core.c

@@ -3219,6 +3219,9 @@ static int ccs_probe(struct i2c_client *client)
 			sensor->pll.op_lanes = sensor->pll.csi2.lanes;
 		}
 	}
+	if (CCS_LIM(sensor, CLOCK_TREE_PLL_CAPABILITY) &
+	    CCS_CLOCK_TREE_PLL_CAPABILITY_EXT_DIVIDER)
+		sensor->pll.flags |= CCS_PLL_FLAG_EXT_IP_PLL_DIVIDER;
 	sensor->pll.ext_clk_freq_hz = sensor->hwcfg.ext_clk;
 	sensor->pll.scale_n = CCS_LIM(sensor, SCALER_N_MIN);