sh: pfc: Variable bitfield width config register support

Add support for variable config reg hardware by adding
the macro PINMUX_CFG_REG_VAR(). The width of each bitfield
needs to be passed to the macro, and the correct space must
be consumed by each bitfield in the enum table following the
macro. Data registers still need to have fixed bitfields.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

drivers/sh/pfc.c

@@ -174,10 +174,19 @@ static void config_reg_helper(struct pinmux_info *gpioc,
 			      unsigned long *maskp,
 			      unsigned long *posp)
 {
+	int k;
+
 	*mapped_regp = pfc_phys_to_virt(gpioc, crp->reg);
 
-	*maskp = (1 << crp->field_width) - 1;
-	*posp = crp->reg_width - ((in_pos + 1) * crp->field_width);
+	if (crp->field_width) {
+		*maskp = (1 << crp->field_width) - 1;
+		*posp = crp->reg_width - ((in_pos + 1) * crp->field_width);
+	} else {
+		*maskp = (1 << crp->var_field_width[in_pos]) - 1;
+		*posp = crp->reg_width;
+		for (k = 0; k <= in_pos; k++)
+			*posp -= crp->var_field_width[k];
+	}
 }
 
 static int read_config_reg(struct pinmux_info *gpioc,
@@ -303,8 +312,8 @@ static int get_config_reg(struct pinmux_info *gpioc, pinmux_enum_t enum_id,
 			  unsigned long **cntp)
 {
 	struct pinmux_cfg_reg *config_reg;
-	unsigned long r_width, f_width;
-	int k, n;
+	unsigned long r_width, f_width, curr_width, ncomb;
+	int k, m, n, pos, bit_pos;
 
 	k = 0;
 	while (1) {
@@ -315,14 +324,27 @@ static int get_config_reg(struct pinmux_info *gpioc, pinmux_enum_t enum_id,
 
 		if (!r_width)
 			break;
-		for (n = 0; n < (r_width / f_width) * (1 << f_width); n++) {
-			if (config_reg->enum_ids[n] == enum_id) {
-				*crp = config_reg;
-				*fieldp = n / (1 << f_width);
-				*valuep = n % (1 << f_width);
-				*cntp = &config_reg->cnt[n / (1 << f_width)];
-				return 0;
+
+		pos = 0;
+		m = 0;
+		for (bit_pos = 0; bit_pos < r_width; bit_pos += curr_width) {
+			if (f_width)
+				curr_width = f_width;
+			else
+				curr_width = config_reg->var_field_width[m];
+
+			ncomb = 1 << curr_width;
+			for (n = 0; n < ncomb; n++) {
+				if (config_reg->enum_ids[pos + n] == enum_id) {
+					*crp = config_reg;
+					*fieldp = m;
+					*valuep = n;
+					*cntp = &config_reg->cnt[m];
+					return 0;
+				}
 			}
+			pos += ncomb;
+			m++;
 		}
 		k++;
 	}

include/linux/sh_pfc.h

@@ -45,12 +45,19 @@ struct pinmux_cfg_reg {
 	unsigned long reg, reg_width, field_width;
 	unsigned long *cnt;
 	pinmux_enum_t *enum_ids;
+	unsigned long *var_field_width;
 };
 
 #define PINMUX_CFG_REG(name, r, r_width, f_width) \
 	.reg = r, .reg_width = r_width, .field_width = f_width,		\
 	.cnt = (unsigned long [r_width / f_width]) {}, \
-	.enum_ids = (pinmux_enum_t [(r_width / f_width) * (1 << f_width)]) \
+	.enum_ids = (pinmux_enum_t [(r_width / f_width) * (1 << f_width)])
+
+#define PINMUX_CFG_REG_VAR(name, r, r_width, var_fw0, var_fwn...) \
+	.reg = r, .reg_width = r_width,	\
+	.cnt = (unsigned long [r_width]) {}, \
+	.var_field_width = (unsigned long [r_width]) { var_fw0, var_fwn, 0 }, \
+	.enum_ids = (pinmux_enum_t [])
 
 struct pinmux_data_reg {
 	unsigned long reg, reg_width, reg_shadow;