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>

drivers/base/regmap/regmap-irq.c

@@ -39,6 +39,7 @@ struct regmap_irq_chip_data {
  unsigned int *type_buf;
  unsigned int *type_buf_def;
  unsigned int **virt_buf;
+ unsigned int **config_buf;
 
  unsigned int irq_reg_stride;
 
@@ -228,6 +229,17 @@ static void regmap_irq_sync_unlock(struct irq_data *data)
  }
  }
 
+ for (i = 0; i < d->chip->num_config_bases; i++) {
+ for (j = 0; j < d->chip->num_config_regs; j++) {
+ reg = sub_irq_reg(d, d->chip->config_base[i], j);
+ ret = regmap_write(map, reg, d->config_buf[i][j]);
+ if (ret)
+ dev_err(d->map->dev,
+ "Failed to write config %x: %d\n",
+ reg, ret);
+ }
+ }
+
  if (d->chip->runtime_pm)
  pm_runtime_put(map->dev);
 
@@ -287,7 +299,7 @@ static int regmap_irq_set_type(struct irq_data *data, unsigned int type)
  struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
  struct regmap *map = d->map;
  const struct regmap_irq *irq_data = irq_to_regmap_irq(d, data->hwirq);
- int reg;
+ int reg, ret;
  const struct regmap_irq_type *t = &irq_data->type;
 
  if ((t->types_supported & type) != type)
@@ -327,9 +339,19 @@ static int regmap_irq_set_type(struct irq_data *data, unsigned int type)
  return -EINVAL;
  }
 
- if (d->chip->set_type_virt)
- return d->chip->set_type_virt(d->virt_buf, type, data->hwirq,
- reg);
+ if (d->chip->set_type_virt) {
+ ret = d->chip->set_type_virt(d->virt_buf, type, data->hwirq,
+ reg);
+ if (ret)
+ return ret;
+ }
+
+ if (d->chip->set_type_config) {
+ ret = d->chip->set_type_config(d->config_buf, type,
+ irq_data, reg);
+ if (ret)
+ return ret;
+ }
 
  return 0;
 }
@@ -599,6 +621,61 @@ static const struct irq_domain_ops regmap_domain_ops = {
  .xlate = irq_domain_xlate_onetwocell,
 };
 
+/**
+ * regmap_irq_set_type_config_simple() - Simple IRQ type configuration callback.
+ * @buf: Buffer containing configuration register values, this is a 2D array of
+ * `num_config_bases` rows, each of `num_config_regs` elements.
+ * @type: The requested IRQ type.
+ * @irq_data: The IRQ being configured.
+ * @idx: Index of the irq's config registers within each array `buf[i]`
+ *
+ * This is a &struct regmap_irq_chip->set_type_config callback suitable for
+ * chips with one config register. Register values are updated according to
+ * the &struct regmap_irq_type data associated with an IRQ.
+ */
+int regmap_irq_set_type_config_simple(unsigned int **buf, unsigned int type,
+ const struct regmap_irq *irq_data, int idx)
+{
+ const struct regmap_irq_type *t = &irq_data->type;
+
+ if (t->type_reg_mask)
+ buf[0][idx] &= ~t->type_reg_mask;
+ else
+ buf[0][idx] &= ~(t->type_falling_val |
+ t->type_rising_val |
+ t->type_level_low_val |
+ t->type_level_high_val);
+
+ switch (type) {
+ case IRQ_TYPE_EDGE_FALLING:
+ buf[0][idx] |= t->type_falling_val;
+ break;
+
+ case IRQ_TYPE_EDGE_RISING:
+ buf[0][idx] |= t->type_rising_val;
+ break;
+
+ case IRQ_TYPE_EDGE_BOTH:
+ buf[0][idx] |= (t->type_falling_val |
+ t->type_rising_val);
+ break;
+
+ case IRQ_TYPE_LEVEL_HIGH:
+ buf[0][idx] |= t->type_level_high_val;
+ break;
+
+ case IRQ_TYPE_LEVEL_LOW:
+ buf[0][idx] |= t->type_level_low_val;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(regmap_irq_set_type_config_simple);
+
 /**
  * regmap_add_irq_chip_fwnode() - Use standard regmap IRQ controller handling
  *
@@ -724,6 +801,24 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
  }
  }
 
+ if (chip->num_config_bases && chip->num_config_regs) {
+ /*
+ * Create config_buf[num_config_bases][num_config_regs]
+ */
+ d->config_buf = kcalloc(chip->num_config_bases,
+ sizeof(*d->config_buf), GFP_KERNEL);
+ if (!d->config_buf)
+ goto err_alloc;
+
+ for (i = 0; i < chip->num_config_regs; i++) {
+ d->config_buf[i] = kcalloc(chip->num_config_regs,
+ sizeof(**d->config_buf),
+ GFP_KERNEL);
+ if (!d->config_buf[i])
+ goto err_alloc;
+ }
+ }
+
  d->irq_chip = regmap_irq_chip;
  d->irq_chip.name = chip->name;
  d->irq = irq;
@@ -894,6 +989,11 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
  kfree(d->virt_buf[i]);
  kfree(d->virt_buf);
  }
+ if (d->config_buf) {
+ for (i = 0; i < chip->num_config_bases; i++)
+ kfree(d->config_buf[i]);
+ kfree(d->config_buf);
+ }
  kfree(d);
  return ret;
 }
@@ -934,7 +1034,7 @@ EXPORT_SYMBOL_GPL(regmap_add_irq_chip);
 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *d)
 {
  unsigned int virq;
- int hwirq;
+ int i, hwirq;
 
  if (!d)
  return;
@@ -964,6 +1064,11 @@ void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *d)
  kfree(d->mask_buf);
  kfree(d->status_reg_buf);
  kfree(d->status_buf);
+ if (d->config_buf) {
+ for (i = 0; i < d->chip->num_config_bases; i++)
+ kfree(d->config_buf[i]);
+ kfree(d->config_buf);
+ }
  kfree(d);
 }
 EXPORT_SYMBOL_GPL(regmap_del_irq_chip);

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);