clk: sunxi-ng: div: Allow to set a maximum

Some dividers might have a maximum value that is lower than the width of
the register.

Add a field to _ccu_div to handle those case properly. If the field is set
to 0, the code will assume that the maximum value is the maximum one that
can be used with the field register width.

Otherwise, we'll use whatever value has been set.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>

1 files changed, 20 insertions, 4 deletions

diff --git a/drivers/clk/sunxi-ng/ccu_div.h b/drivers/clk/sunxi-ng/ccu_div.h
index e1b1326..34c3388 100644
--- a/drivers/clk/sunxi-ng/ccu_div.h
+++ b/drivers/clk/sunxi-ng/ccu_div.h
@@ -23,6 +23,9 @@
  * struct _ccu_div - Internal divider description
  * @shift: Bit offset of the divider in its register
  * @width: Width of the divider field in its register
+ * @max: Maximum value allowed for that divider. This is the
+ *       arithmetic value, not the maximum value to be set in the
+ *       register.
  * @flags: clk_divider flags to apply on this divider
  * @table: Divider table pointer (if applicable)
  *
@@ -37,6 +40,8 @@ struct _ccu_div {
 	u8			shift;
 	u8			width;
 
+	u32			max;
+
 	u32			flags;
 
 	struct clk_div_table	*table;
@@ -50,14 +55,25 @@ struct _ccu_div {
 		.table	= _table,					\
 	}
 
-#define _SUNXI_CCU_DIV_FLAGS(_shift, _width, _flags)			\
-	_SUNXI_CCU_DIV_TABLE_FLAGS(_shift, _width, NULL, _flags)
-
 #define _SUNXI_CCU_DIV_TABLE(_shift, _width, _table)			\
 	_SUNXI_CCU_DIV_TABLE_FLAGS(_shift, _width, _table, 0)
 
+#define _SUNXI_CCU_DIV_MAX_FLAGS(_shift, _width, _max, _flags) \
+	{								\
+		.shift	= _shift,					\
+		.width	= _width,					\
+		.flags	= _flags,					\
+		.max	= _max,						\
+	}
+
+#define _SUNXI_CCU_DIV_FLAGS(_shift, _width, _flags)			\
+	_SUNXI_CCU_DIV_MAX_FLAGS(_shift, _width, 0, _flags)
+
+#define _SUNXI_CCU_DIV_MAX(_shift, _width, _max)			\
+	_SUNXI_CCU_DIV_MAX_FLAGS(_shift, _width, _max, 0)
+
 #define _SUNXI_CCU_DIV(_shift, _width)					\
-	_SUNXI_CCU_DIV_TABLE_FLAGS(_shift, _width, NULL, 0)
+	_SUNXI_CCU_DIV_FLAGS(_shift, _width, 0)
 
 struct ccu_div {
 	u32			enable;