in regmap/regmap.c [2458:2535]
static int _regmap_multi_reg_write(struct regmap *map,
const struct reg_sequence *regs,
size_t num_regs)
{
int i;
int ret;
if (!map->can_multi_write) {
for (i = 0; i < num_regs; i++) {
ret = _regmap_write(map, regs[i].reg, regs[i].def);
if (ret != 0)
return ret;
if (regs[i].delay_us) {
if (map->can_sleep)
fsleep(regs[i].delay_us);
else
udelay(regs[i].delay_us);
}
}
return 0;
}
if (!map->format.parse_inplace)
return -EINVAL;
if (map->writeable_reg)
for (i = 0; i < num_regs; i++) {
int reg = regs[i].reg;
if (!map->writeable_reg(map->dev, reg))
return -EINVAL;
if (!IS_ALIGNED(reg, map->reg_stride))
return -EINVAL;
}
if (!map->cache_bypass) {
for (i = 0; i < num_regs; i++) {
unsigned int val = regs[i].def;
unsigned int reg = regs[i].reg;
ret = regcache_write(map, reg, val);
if (ret) {
dev_err(map->dev,
"Error in caching of register: %x ret: %d\n",
reg, ret);
return ret;
}
}
if (map->cache_only) {
map->cache_dirty = true;
return 0;
}
}
WARN_ON(!map->bus);
for (i = 0; i < num_regs; i++) {
unsigned int reg = regs[i].reg;
struct regmap_range_node *range;
/* Coalesce all the writes between a page break or a delay
* in a sequence
*/
range = _regmap_range_lookup(map, reg);
if (range || regs[i].delay_us) {
size_t len = sizeof(struct reg_sequence)*num_regs;
struct reg_sequence *base = kmemdup(regs, len,
GFP_KERNEL);
if (!base)
return -ENOMEM;
ret = _regmap_range_multi_paged_reg_write(map, base,
num_regs);
kfree(base);
return ret;
}
}
return _regmap_raw_multi_reg_write(map, regs, num_regs);
}