regmap-irq: Introduce config registers for irq types

Config registers provide a more uniform approach to handling irq type
registers. They are essentially an extension of the virtual registers
used by the qcom-pm8008 driver.

Config registers can be represented as a 2D array:

    config_base[0]      reg0,0      reg0,1      reg0,2      reg0,3
    config_base[1]      reg1,0      reg1,1      reg1,2      reg1,3
    config_base[2]      reg2,0      reg2,1      reg2,2      reg2,3

There are 'num_config_bases' base registers, each of which is used to
address 'num_config_regs' registers. The addresses are calculated in
the same way as for other bases. It is assumed that an irq's type is
controlled by one column of registers; that column is identified by
the irq's 'type_reg_offset'.

The set_type_config() callback is responsible for updating the config
register contents. It receives an array of buffers (each represents a
row of registers) and the index of the column to update, along with
the 'struct regmap_irq' description and requested irq type.

Buffered values are written to registers in regmap_irq_sync_unlock().
Note that the entire register contents are overwritten, which is a
minor change in behavior from type registers via 'type_base'.

Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@gmail.com>
Link: https://lore.kernel.org/r/20220623211420.918875-9-aidanmacdonald.0x0@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

include/linux/regmap.h

@@ -1475,6 +1475,7 @@ struct regmap_irq_sub_irq_map {
  * @wake_base:   Base address for wake enables.  If zero unsupported.
  * @type_base:   Base address for irq type.  If zero unsupported.
  * @virt_reg_base:   Base addresses for extra config regs.
+ * @config_base: Base address for IRQ type config regs. If null unsupported.
  * @irq_reg_stride:  Stride to use for chips where registers are not contiguous.
  * @init_ack_masked: Ack all masked interrupts once during initalization.
  * @mask_invert: Inverted mask register: cleared bits are masked out.
@@ -1504,12 +1505,15 @@ struct regmap_irq_sub_irq_map {
  * @num_type_reg:    Number of type registers.
  * @num_virt_regs:   Number of non-standard irq configuration registers.
  *		     If zero unsupported.
+ * @num_config_bases:	Number of config base registers.
+ * @num_config_regs:	Number of config registers for each config base register.
  * @handle_pre_irq:  Driver specific callback to handle interrupt from device
  *		     before regmap_irq_handler process the interrupts.
  * @handle_post_irq: Driver specific callback to handle interrupt from device
  *		     after handling the interrupts in regmap_irq_handler().
  * @set_type_virt:   Driver specific callback to extend regmap_irq_set_type()
  *		     and configure virt regs.
+ * @set_type_config: Callback used for configuring irq types.
  * @irq_drv_data:    Driver specific IRQ data which is passed as parameter when
  *		     driver specific pre/post interrupt handler is called.
  *
@@ -1532,6 +1536,7 @@ struct regmap_irq_chip {
 	unsigned int wake_base;
 	unsigned int type_base;
 	unsigned int *virt_reg_base;
+	const unsigned int *config_base;
 	unsigned int irq_reg_stride;
 	unsigned int init_ack_masked:1;
 	unsigned int mask_invert:1;
@@ -1553,16 +1558,23 @@ struct regmap_irq_chip {
 
 	int num_type_reg;
 	int num_virt_regs;
+	int num_config_bases;
+	int num_config_regs;
 
 	int (*handle_pre_irq)(void *irq_drv_data);
 	int (*handle_post_irq)(void *irq_drv_data);
 	int (*set_type_virt)(unsigned int **buf, unsigned int type,
 			     unsigned long hwirq, int reg);
+	int (*set_type_config)(unsigned int **buf, unsigned int type,
+			       const struct regmap_irq *irq_data, int idx);
 	void *irq_drv_data;
 };
 
 struct regmap_irq_chip_data;
 
+int regmap_irq_set_type_config_simple(unsigned int **buf, unsigned int type,
+				      const struct regmap_irq *irq_data, int idx);
+
 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 			int irq_base, const struct regmap_irq_chip *chip,
 			struct regmap_irq_chip_data **data);