[PATCH v2 11/12] regmap-irq: Add get_irq_reg() callback

Aidan MacDonald
2022-06-23T21:14:17Z

Replace the internal sub_irq_reg() function with a public callback
that drivers can use when they have more complex register layouts.
The default implementation is regmap_irq_get_irq_reg_linear(), used
if the chip doesn't provide its own callback.

Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@gmail.com>
---
drivers/base/regmap/regmap-irq.c | 126 ++++++++++++++++++++-----------
include/linux/regmap.h | 15 +++-
2 files changed, 93 insertions(+), 48 deletions(-)

diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c
index 2c724ae185c4..71de097847a7 100644
--- a/drivers/base/regmap/regmap-irq.c
+++ b/drivers/base/regmap/regmap-irq.c
@@ -46,30 +46,12 @@ struct regmap_irq_chip_data {

unsigned int irq_reg_stride;

+ unsigned int (*get_irq_reg)(struct regmap_irq_chip_data *data,
+ unsigned int base, int index);
+
unsigned int clear_status:1;
};

-static int sub_irq_reg(struct regmap_irq_chip_data *data,
- unsigned int base_reg, int i)
-{
- const struct regmap_irq_chip *chip = data->chip;
- struct regmap *map = data->map;
- struct regmap_irq_sub_irq_map *subreg;
- unsigned int offset;
- int reg = 0;
-
- if (!chip->sub_reg_offsets || !chip->not_fixed_stride) {
- /* Assume linear mapping */
- reg = base_reg + (i * map->reg_stride * data->irq_reg_stride);
- } else {
- subreg = &chip->sub_reg_offsets[i];
- offset = subreg->offset[0];
- reg = base_reg + offset;
- }
-
- return reg;
-}
-
static inline const
struct regmap_irq *irq_to_regmap_irq(struct regmap_irq_chip_data *data,
int irq)
@@ -81,7 +63,13 @@ static bool regmap_irq_can_bulk_read_status(struct regmap_irq_chip_data *data)
{
struct regmap *map = data->map;

+ /*
+ * While possible that a user-defined ->get_irq_reg() callback might
+ * be linear enough to support bulk reads, most of the time it won't.
+ * Therefore only allow them if the default callback is being used.
+ */
return data->irq_reg_stride == 1 && map->reg_stride == 1 &&
+ data->get_irq_reg == regmap_irq_get_irq_reg_linear &&
!map->use_single_read;
}

@@ -109,7 +97,7 @@ static void regmap_irq_sync_unlock(struct irq_data *data)

if (d->clear_status) {
for (i = 0; i < d->chip->num_regs; i++) {
- reg = sub_irq_reg(d, d->chip->status_base, i);
+ reg = d->get_irq_reg(d, d->chip->status_base, i);

ret = regmap_read(map, reg, &val);
if (ret)
@@ -127,7 +115,7 @@ static void regmap_irq_sync_unlock(struct irq_data *data)
*/
for (i = 0; i < d->chip->num_regs; i++) {
if (d->mask_base) {
- reg = sub_irq_reg(d, d->mask_base, i);
+ reg = d->get_irq_reg(d, d->mask_base, i);
ret = regmap_update_bits(d->map, reg,
d->mask_buf_def[i], d->mask_buf[i]);
if (ret)
@@ -136,7 +124,7 @@ static void regmap_irq_sync_unlock(struct irq_data *data)
}

if (d->unmask_base) {
- reg = sub_irq_reg(d, d->unmask_base, i);
+ reg = d->get_irq_reg(d, d->unmask_base, i);
ret = regmap_update_bits(d->map, reg,
d->mask_buf_def[i], ~d->mask_buf[i]);
if (ret)
@@ -144,7 +132,7 @@ static void regmap_irq_sync_unlock(struct irq_data *data)
reg);
}

- reg = sub_irq_reg(d, d->chip->wake_base, i);
+ reg = d->get_irq_reg(d, d->chip->wake_base, i);
if (d->wake_buf) {
if (d->chip->wake_invert)
ret = regmap_update_bits(d->map, reg,
@@ -168,7 +156,7 @@ static void regmap_irq_sync_unlock(struct irq_data *data)
* it'll be ignored in irq handler, then may introduce irq storm
*/
if (d->mask_buf[i] && (d->chip->ack_base || d->chip->use_ack)) {
- reg = sub_irq_reg(d, d->chip->ack_base, i);
+ reg = d->get_irq_reg(d, d->chip->ack_base, i);

/* some chips ack by write 0 */
if (d->chip->ack_invert)
@@ -192,7 +180,7 @@ static void regmap_irq_sync_unlock(struct irq_data *data)
for (i = 0; i < d->chip->num_type_reg; i++) {
if (!d->type_buf_def[i])
continue;
- reg = sub_irq_reg(d, d->chip->type_base, i);
+ reg = d->get_irq_reg(d, d->chip->type_base, i);
if (d->chip->type_invert)
ret = regmap_update_bits(d->map, reg,
d->type_buf_def[i], ~d->type_buf[i]);
@@ -208,8 +196,8 @@ static void regmap_irq_sync_unlock(struct irq_data *data)
if (d->chip->num_virt_regs) {
for (i = 0; i < d->chip->num_virt_regs; i++) {
for (j = 0; j < d->chip->num_regs; j++) {
- reg = sub_irq_reg(d, d->chip->virt_reg_base[i],
- j);
+ reg = d->get_irq_reg(d, d->chip->virt_reg_base[i],
+ j);
ret = regmap_write(map, reg, d->virt_buf[i][j]);
if (ret != 0)
dev_err(d->map->dev,
@@ -221,7 +209,7 @@ 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);
+ reg = d->get_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,
@@ -382,14 +370,17 @@ static inline int read_sub_irq_data(struct regmap_irq_chip_data *data,
const struct regmap_irq_chip *chip = data->chip;
struct regmap *map = data->map;
struct regmap_irq_sub_irq_map *subreg;
+ unsigned int reg;
int i, ret = 0;

if (!chip->sub_reg_offsets) {
- /* Assume linear mapping */
- ret = regmap_read(map, chip->status_base +
- (b * map->reg_stride * data->irq_reg_stride),
- &data->status_buf[b]);
+ reg = data->get_irq_reg(data, chip->status_base, b);
+ ret = regmap_read(map, reg, &data->status_buf[b]);
} else {
+ /*
+ * Note we can't use ->get_irq_reg() here because the offsets
+ * in 'subreg' are *not* interchangeable with indices.
+ */
subreg = &chip->sub_reg_offsets[b];
for (i = 0; i < subreg->num_regs; i++) {
unsigned int offset = subreg->offset[i];
@@ -455,10 +446,18 @@ static irqreturn_t regmap_irq_thread(int irq, void *d)
* sake of simplicity. and add bulk reads only if needed
*/
for (i = 0; i < chip->num_main_regs; i++) {
- ret = regmap_read(map, chip->main_status +
- (i * map->reg_stride
- * data->irq_reg_stride),
- &data->main_status_buf[i]);
+ /*
+ * For not_fixed_stride, don't use ->get_irq_reg().
+ * It would produce an incorrect result.
+ */
+ if (data->chip->not_fixed_stride)
+ reg = chip->main_status +
+ i * map->reg_stride * data->irq_reg_stride;
+ else
+ reg = data->get_irq_reg(data,
+ chip->main_status, i);
+
+ ret = regmap_read(map, reg, &data->main_status_buf[i]);
if (ret) {
dev_err(map->dev,
"Failed to read IRQ status %d\n",
@@ -523,7 +522,7 @@ static irqreturn_t regmap_irq_thread(int irq, void *d)

} else {
for (i = 0; i < data->chip->num_regs; i++) {
- unsigned int reg = sub_irq_reg(data,
+ unsigned int reg = data->get_irq_reg(data,
data->chip->status_base, i);
ret = regmap_read(map, reg, &data->status_buf[i]);

@@ -551,7 +550,7 @@ static irqreturn_t regmap_irq_thread(int irq, void *d)
data->status_buf[i] &= ~data->mask_buf[i];

if (data->status_buf[i] && (chip->ack_base || chip->use_ack)) {
- reg = sub_irq_reg(data, data->chip->ack_base, i);
+ reg = data->get_irq_reg(data, data->chip->ack_base, i);

if (chip->ack_invert)
ret = regmap_write(map, reg,
@@ -611,6 +610,36 @@ static const struct irq_domain_ops regmap_domain_ops = {
.xlate = irq_domain_xlate_onetwocell,
};

+/**
+ * regmap_irq_get_irq_reg_linear() - Linear IRQ register mapping callback.
+ * @data: Data for the &struct regmap_irq_chip
+ * @base: Base register
+ * @index: Register index
+ *
+ * Returns the register address corresponding to the given @base and @index
+ * by the formula ``base + index * regmap_stride * irq_reg_stride``.
+ */
+unsigned int regmap_irq_get_irq_reg_linear(struct regmap_irq_chip_data *data,
+ unsigned int base, int index)
+{
+ const struct regmap_irq_chip *chip = data->chip;
+ struct regmap *map = data->map;
+
+ /*
+ * FIXME: This is for backward compatibility and should be removed
+ * when not_fixed_stride is dropped (it's only used by qcom-pm8008).
+ */
+ if (chip->not_fixed_stride && chip->sub_reg_offsets) {
+ struct regmap_irq_sub_irq_map *subreg;
+
+ subreg = &chip->sub_reg_offsets[0];
+ return base + subreg->offset[0];
+ }
+
+ return base + index * map->reg_stride * chip->irq_reg_stride;
+}
+EXPORT_SYMBOL_GPL(regmap_irq_get_irq_reg_linear);
+
/**
* regmap_irq_set_type_config_simple() - Simple IRQ type configuration callback.
* @buf: Buffer containing configuration register values, this is a 2D array of
@@ -862,6 +891,11 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
else
d->irq_reg_stride = 1;

+ if (chip->get_irq_reg)
+ d->get_irq_reg = chip->get_irq_reg;
+ else
+ d->get_irq_reg = regmap_irq_get_irq_reg_linear;
+
if (regmap_irq_can_bulk_read_status(d)) {
d->status_reg_buf = kmalloc_array(chip->num_regs,
map->format.val_bytes,
@@ -881,7 +915,7 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
d->mask_buf[i] = d->mask_buf_def[i];

if (d->mask_base) {
- reg = sub_irq_reg(d, d->mask_base, i);
+ reg = d->get_irq_reg(d, d->mask_base, i);
ret = regmap_update_bits(d->map, reg,
d->mask_buf_def[i], d->mask_buf[i]);
if (ret) {
@@ -892,7 +926,7 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
}

if (d->unmask_base) {
- reg = sub_irq_reg(d, d->unmask_base, i);
+ reg = d->get_irq_reg(d, d->unmask_base, i);
ret = regmap_update_bits(d->map, reg,
d->mask_buf_def[i], ~d->mask_buf[i]);
if (ret) {
@@ -906,7 +940,7 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
continue;

/* Ack masked but set interrupts */
- reg = sub_irq_reg(d, d->chip->status_base, i);
+ reg = d->get_irq_reg(d, d->chip->status_base, i);
ret = regmap_read(map, reg, &d->status_buf[i]);
if (ret != 0) {
dev_err(map->dev, "Failed to read IRQ status: %d\n",
@@ -918,7 +952,7 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
d->status_buf[i] = ~d->status_buf[i];

if (d->status_buf[i] && (chip->ack_base || chip->use_ack)) {
- reg = sub_irq_reg(d, d->chip->ack_base, i);
+ reg = d->get_irq_reg(d, d->chip->ack_base, i);
if (chip->ack_invert)
ret = regmap_write(map, reg,
~(d->status_buf[i] & d->mask_buf[i]));
@@ -943,7 +977,7 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
if (d->wake_buf) {
for (i = 0; i < chip->num_regs; i++) {
d->wake_buf[i] = d->mask_buf_def[i];
- reg = sub_irq_reg(d, d->chip->wake_base, i);
+ reg = d->get_irq_reg(d, d->chip->wake_base, i);

if (chip->wake_invert)
ret = regmap_update_bits(d->map, reg,
@@ -963,7 +997,7 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,

if (chip->num_type_reg && !chip->type_in_mask) {
for (i = 0; i < chip->num_type_reg; ++i) {
- reg = sub_irq_reg(d, d->chip->type_base, i);
+ reg = d->get_irq_reg(d, d->chip->type_base, i);

ret = regmap_read(map, reg, &d->type_buf_def[i]);

diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 708f36dfaeda..ae5f1f7d4b5a 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -1424,6 +1424,8 @@ struct regmap_irq_sub_irq_map {
unsigned int *offset;
};

+struct regmap_irq_chip_data;
+
/**
* struct regmap_irq_chip - Description of a generic regmap irq_chip.
*
@@ -1515,6 +1517,13 @@ struct regmap_irq_sub_irq_map {
* and configure virt regs. Deprecated, use @set_type_config
* callback and config registers instead.
* @set_type_config: Callback used for configuring irq types.
+ * @get_irq_reg: Callback for mapping (base register, index) pairs to register
+ * addresses. The base register will be one of @status_base,
+ * @mask_base, etc., @main_status, or any of @config_base.
+ * The index will be in the range [0, num_main_regs[ for the
+ * main status base, [0, num_type_settings[ for any config
+ * register base, and [0, num_regs[ for any other base.
+ * If unspecified then regmap_irq_get_irq_reg_linear() is used.
* @irq_drv_data: Driver specific IRQ data which is passed as parameter when
* driver specific pre/post interrupt handler is called.
*
@@ -1569,11 +1578,13 @@ struct regmap_irq_chip {
unsigned long hwirq, int reg);
int (*set_type_config)(unsigned int **buf, unsigned int type,
const struct regmap_irq *irq_data, int idx);
+ unsigned int (*get_irq_reg)(struct regmap_irq_chip_data *data,
+ unsigned int base, int index);
void *irq_drv_data;
};

-struct regmap_irq_chip_data;
-
+unsigned int regmap_irq_get_irq_reg_linear(struct regmap_irq_chip_data *data,
+ unsigned int base, int index);
int regmap_irq_set_type_config_simple(unsigned int **buf, unsigned int type,
const struct regmap_irq *irq_data, int idx);

--
2.35.1