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regmap: irq: Use a bulk read for interrupt status where possible

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If the interrupt status registers are a single block of registers and the
chip supports bulk reads then do a single bulk read rather than pay the
extra I/O cost. This restores the original behaviour which was lost when
support for register striding was added.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Mark Brown 2013-01-03 14:27:15 +00:00
parent bbae92ca49
commit a7440eaa90
1 changed files with 60 additions and 7 deletions
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67
drivers/base/regmap/regmap-irq.c
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@ -34,6 +34,7 @@ struct regmap_irq_chip_data {
int irq;
int wake_count;
void *status_reg_buf;
unsigned int *status_buf;
unsigned int *mask_buf;
unsigned int *mask_buf_def;
@ -170,18 +171,60 @@ static irqreturn_t regmap_irq_thread(int irq, void *d)
}
}
for (i = 0; i < data->chip->num_regs; i++) {
ret = regmap_read(map, chip->status_base + (i * map->reg_stride
* data->irq_reg_stride),
&data->status_buf[i]);
/*
* Read in the statuses, using a single bulk read if possible
* in order to reduce the I/O overheads.
*/
if (!map->use_single_rw && map->reg_stride == 1 &&
data->irq_reg_stride == 1) {
u8 *buf8 = data->status_reg_buf;
u16 *buf16 = data->status_reg_buf;
u32 *buf32 = data->status_reg_buf;
BUG_ON(!data->status_reg_buf);
ret = regmap_bulk_read(map, chip->status_base,
data->status_reg_buf,
chip->num_regs);
if (ret != 0) {
dev_err(map->dev, "Failed to read IRQ status: %d\n",
ret);
if (chip->runtime_pm)
pm_runtime_put(map->dev);
ret);
return IRQ_NONE;
}
for (i = 0; i < data->chip->num_regs; i++) {
switch (map->format.val_bytes) {
case 1:
data->status_buf[i] = buf8[i];
break;
case 2:
data->status_buf[i] = buf16[i];
break;
case 4:
data->status_buf[i] = buf32[i];
break;
default:
BUG();
return IRQ_NONE;
}
}
} else {
for (i = 0; i < data->chip->num_regs; i++) {
ret = regmap_read(map, chip->status_base +
(i * map->reg_stride
* data->irq_reg_stride),
&data->status_buf[i]);
if (ret != 0) {
dev_err(map->dev,
"Failed to read IRQ status: %d\n",
ret);
if (chip->runtime_pm)
pm_runtime_put(map->dev);
return IRQ_NONE;
}
}
}
/*
@ -327,6 +370,14 @@ int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
else
d->irq_reg_stride = 1;
if (!map->use_single_rw && map->reg_stride == 1 &&
d->irq_reg_stride == 1) {
d->status_reg_buf = kmalloc(map->format.val_bytes *
chip->num_regs, GFP_KERNEL);
if (!d->status_reg_buf)
goto err_alloc;
}
mutex_init(&d->lock);
for (i = 0; i < chip->num_irqs; i++)
@ -397,6 +448,7 @@ err_alloc:
kfree(d->mask_buf_def);
kfree(d->mask_buf);
kfree(d->status_buf);
kfree(d->status_reg_buf);
kfree(d);
return ret;
}
@ -418,6 +470,7 @@ void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *d)
kfree(d->wake_buf);
kfree(d->mask_buf_def);
kfree(d->mask_buf);
kfree(d->status_reg_buf);
kfree(d->status_buf);
kfree(d);
}