Re: [PATCH 3/8] regmap: Add support for using regmap over ssbi

From: Stephen Boyd
Date: Fri Dec 13 2013 - 16:37:17 EST


On 12/13, Mark Brown wrote:
> On Thu, Dec 12, 2013 at 03:13:01PM -0800, Stephen Boyd wrote:
>
> > > bulk_read() should decay to individual reads if there isn't a block
> > > operaton and it's not like the hardware actually supports bulk reads
> > > anyway.
>
> > So regmap_bulk_read() should work if I don't have a map->bus? To make it
> > work with reg_read/write I had to do this. I'm not sure how to make
> > bulk_write work.

I came up with this (possibly ugly) patch. It works for my
specific case but I'm not sure if unpacking the val bits into an
unsigned int and passing that to _regmap_write() is sane. What do
you think?

---8<----
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 1ccd61b..333c059 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -1514,11 +1514,9 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
{
int ret = 0, i;
size_t val_bytes = map->format.val_bytes;
- void *wval;
+ void *wval = NULL;

- if (!map->bus)
- return -EINVAL;
- if (!map->format.parse_inplace)
+ if (map->bus && !map->format.parse_inplace)
return -EINVAL;
if (reg % map->reg_stride)
return -EINVAL;
@@ -1528,7 +1526,7 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
/* No formatting is require if val_byte is 1 */
if (val_bytes == 1) {
wval = (void *)val;
- } else {
+ } else if (map->bus) {
wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL);
if (!wval) {
ret = -ENOMEM;
@@ -1538,24 +1536,37 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
for (i = 0; i < val_count * val_bytes; i += val_bytes)
map->format.parse_inplace(wval + i);
}
- /*
- * Some devices does not support bulk write, for
- * them we have a series of single write operations.
- */
- if (map->use_single_rw) {
- for (i = 0; i < val_count; i++) {
- ret = _regmap_raw_write(map,
+
+ if (map->bus) {
+ /*
+ * Some devices does not support bulk write, for
+ * them we have a series of single write operations.
+ */
+ if (map->use_single_rw) {
+ for (i = 0; i < val_count; i++) {
+ ret = _regmap_raw_write(map,
reg + (i * map->reg_stride),
val + (i * val_bytes),
val_bytes);
- if (ret != 0)
- return ret;
+ if (ret != 0)
+ return ret;
+ }
+ } else {
+ ret = _regmap_raw_write(map, reg, wval,
+ val_bytes * val_count);
}
} else {
- ret = _regmap_raw_write(map, reg, wval, val_bytes * val_count);
+ for (i = 0; i < val_count; i++) {
+ unsigned int ival;
+ ival = *(unsigned int *)(val + (i * val_bytes));
+ ret = _regmap_write(map, reg + (i * map->reg_stride),
+ ival);
+ if (ret != 0)
+ goto out;
+ }
}

- if (val_bytes != 1)
+ if (val_bytes != 1 && map->bus)
kfree(wval);

out:

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