regmap: introduce tables for readable/writeable/volatile/precious checks
Many of the regmap enabled drivers implementing one or more of the
readable, writeable, volatile and precious methods use the same code
pattern:
return ((reg >= X && reg <= Y) || (reg >= W && reg <= Z) || ...)
Switch to a data driven approach, using tables to describe
readable/writeable/volatile and precious registers ranges instead.
The table based check can still be overridden by passing the usual function
pointers via struct regmap_config.
Signed-off-by: Davide Ciminaghi <ciminaghi@gnudd.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 0e819e3..3bdb1f9 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -53,6 +53,36 @@
REGMAP_ENDIAN_NATIVE,
};
+/**
+ * A register range, used for access related checks
+ * (readable/writeable/volatile/precious checks)
+ *
+ * @range_min: address of first register
+ * @range_max: address of last register
+ */
+struct regmap_range {
+ unsigned int range_min;
+ unsigned int range_max;
+};
+
+/*
+ * A table of ranges including some yes ranges and some no ranges.
+ * If a register belongs to a no_range, the corresponding check function
+ * will return false. If a register belongs to a yes range, the corresponding
+ * check function will return true. "no_ranges" are searched first.
+ *
+ * @yes_ranges : pointer to an array of regmap ranges used as "yes ranges"
+ * @n_yes_ranges: size of the above array
+ * @no_ranges: pointer to an array of regmap ranges used as "no ranges"
+ * @n_no_ranges: size of the above array
+ */
+struct regmap_access_table {
+ const struct regmap_range *yes_ranges;
+ unsigned int n_yes_ranges;
+ const struct regmap_range *no_ranges;
+ unsigned int n_no_ranges;
+};
+
typedef void (*regmap_lock)(void *);
typedef void (*regmap_unlock)(void *);
@@ -70,22 +100,39 @@
* @val_bits: Number of bits in a register value, mandatory.
*
* @writeable_reg: Optional callback returning true if the register
- * can be written to.
+ * can be written to. If this field is NULL but wr_table
+ * (see below) is not, the check is performed on such table
+ * (a register is writeable if it belongs to one of the ranges
+ * specified by wr_table).
* @readable_reg: Optional callback returning true if the register
- * can be read from.
+ * can be read from. If this field is NULL but rd_table
+ * (see below) is not, the check is performed on such table
+ * (a register is readable if it belongs to one of the ranges
+ * specified by rd_table).
* @volatile_reg: Optional callback returning true if the register
- * value can't be cached.
+ * value can't be cached. If this field is NULL but
+ * volatile_table (see below) is not, the check is performed on
+ * such table (a register is volatile if it belongs to one of
+ * the ranges specified by volatile_table).
* @precious_reg: Optional callback returning true if the rgister
- * should not be read outside of a call from the driver
- * (eg, a clear on read interrupt status register).
- * @lock: Optional lock callback (overrides regmap's default lock
- * function, based on spinlock or mutex).
- * @unlock: As above for unlocking.
- * @lock_arg: this field is passed as the only argument of lock/unlock
- * functions (ignored in case regular lock/unlock functions
- * are not overridden).
+ * should not be read outside of a call from the driver
+ * (eg, a clear on read interrupt status register). If this
+ * field is NULL but precious_table (see below) is not, the
+ * check is performed on such table (a register is precious if
+ * it belongs to one of the ranges specified by precious_table).
+ * @lock: Optional lock callback (overrides regmap's default lock
+ * function, based on spinlock or mutex).
+ * @unlock: As above for unlocking.
+ * @lock_arg: this field is passed as the only argument of lock/unlock
+ * functions (ignored in case regular lock/unlock functions
+ * are not overridden).
*
* @max_register: Optional, specifies the maximum valid register index.
+ * @wr_table: Optional, points to a struct regmap_access_table specifying
+ * valid ranges for write access.
+ * @rd_table: As above, for read access.
+ * @volatile_table: As above, for volatile registers.
+ * @precious_table: As above, for precious registers.
* @reg_defaults: Power on reset values for registers (for use with
* register cache support).
* @num_reg_defaults: Number of elements in reg_defaults.
@@ -130,6 +177,10 @@
void *lock_arg;
unsigned int max_register;
+ const struct regmap_access_table *wr_table;
+ const struct regmap_access_table *rd_table;
+ const struct regmap_access_table *volatile_table;
+ const struct regmap_access_table *precious_table;
const struct reg_default *reg_defaults;
unsigned int num_reg_defaults;
enum regcache_type cache_type;
@@ -280,6 +331,16 @@
int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
int num_regs);
+static inline bool regmap_reg_in_range(unsigned int reg,
+ const struct regmap_range *range)
+{
+ return reg >= range->range_min && reg <= range->range_max;
+}
+
+bool regmap_reg_in_ranges(unsigned int reg,
+ const struct regmap_range *ranges,
+ unsigned int nranges);
+
/**
* Description of an IRQ for the generic regmap irq_chip.
*