clk: at91: clk-generated: fix incorrect index of clk source

Differentiate the generic clock source selection value from the parent
clock index to fix the incorrect assignment of the generic clock
source selection.

Signed-off-by: Wenyou Yang <wenyou.yang@microchip.com>

drivers/clk/at91/clk-generated.c

@@ -53,16 +53,17 @@ static ulong generic_clk_get_rate(struct clk *clk)
 	struct clk parent;
 	ulong clk_rate;
 	u32 tmp, gckdiv;
-	u8 parent_id;
+	u8 clock_source, parent_index;
 	int ret;
 
 	writel(clk->id & AT91_PMC_PCR_PID_MASK, &pmc->pcr);
 	tmp = readl(&pmc->pcr);
-	parent_id = (tmp >> AT91_PMC_PCR_GCKCSS_OFFSET) &
+	clock_source = (tmp >> AT91_PMC_PCR_GCKCSS_OFFSET) &
 		    AT91_PMC_PCR_GCKCSS_MASK;
 	gckdiv = (tmp >> AT91_PMC_PCR_GCKDIV_OFFSET) & AT91_PMC_PCR_GCKDIV_MASK;
 
-	ret = clk_get_by_index(dev_get_parent(clk->dev), parent_id, &parent);
+	parent_index = clock_source - 1;
+	ret = clk_get_by_index(dev_get_parent(clk->dev), parent_index, &parent);
 	if (ret)
 		return 0;
 
@@ -82,7 +83,7 @@ static ulong generic_clk_set_rate(struct clk *clk, ulong rate)
 	ulong tmp_rate, best_rate = rate, parent_rate;
 	int tmp_diff, best_diff = -1;
 	u32 div, best_div = 0;
-	u8 best_parent_id = 0;
+	u8 best_parent_index, best_clock_source = 0;
 	u8 i;
 	u32 tmp;
 	int ret;
@@ -106,7 +107,8 @@ static ulong generic_clk_set_rate(struct clk *clk, ulong rate)
 
 				best_div = div - 1;
 				best_parent = parent;
-				best_parent_id = i;
+				best_parent_index = i;
+				best_clock_source = best_parent_index + 1;
 			}
 
 			if (!best_diff || tmp_rate < rate)
@@ -127,7 +129,7 @@ static ulong generic_clk_set_rate(struct clk *clk, ulong rate)
 	writel(clk->id & AT91_PMC_PCR_PID_MASK, &pmc->pcr);
 	tmp = readl(&pmc->pcr);
 	tmp &= ~(AT91_PMC_PCR_GCKDIV | AT91_PMC_PCR_GCKCSS);
-	tmp |= AT91_PMC_PCR_GCKCSS_(best_parent_id) |
+	tmp |= AT91_PMC_PCR_GCKCSS_(best_clock_source) |
 	       AT91_PMC_PCR_CMD_WRITE |
 	       AT91_PMC_PCR_GCKDIV_(best_div) |
 	       AT91_PMC_PCR_GCKEN;