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authorOpensource [Anthony Olech] <anthony.olech.opensource@diasemi.com>2014-03-04 13:54:02 +0000
committerMark Brown <broonie@linaro.org>2014-03-10 17:09:32 +0000
commite894c3f46c302716d2f156b1f3339e2f96ceb65c (patch)
treed051cf7865aa21b8af4dd6a921c71efde418cfa1 /drivers/base
parent1c18d2ca104c36fc2ce147cce053c62f61d2ea68 (diff)
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regmap: Implementation for regmap_multi_reg_write
This is the implementation of regmap_multi_reg_write() There is a new capability 'can_multi_write' that device drivers must set in order to use this multi reg write mode. This replaces the first definition, which just defined the API. Signed-off-by: Anthony Olech <anthony.olech.opensource@diasemi.com> Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'drivers/base')
-rw-r--r--drivers/base/regmap/internal.h2
-rw-r--r--drivers/base/regmap/regmap.c188
2 files changed, 174 insertions, 16 deletions
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index 33414b1de201..7d1326985bee 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -134,6 +134,8 @@ struct regmap {
/* if set, converts bulk rw to single rw */
bool use_single_rw;
+ /* if set, the device supports multi write mode */
+ bool can_multi_write;
struct rb_root range_tree;
void *selector_work_buf; /* Scratch buffer used for selector */
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 35ab7baffcc5..c69bbc06dfbb 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -439,6 +439,7 @@ struct regmap *regmap_init(struct device *dev,
else
map->reg_stride = 1;
map->use_single_rw = config->use_single_rw;
+ map->can_multi_write = config->can_multi_write;
map->dev = dev;
map->bus = bus;
map->bus_context = bus_context;
@@ -1576,41 +1577,196 @@ out:
}
EXPORT_SYMBOL_GPL(regmap_bulk_write);
+/*
+ * _regmap_raw_multi_reg_write()
+ *
+ * the (register,newvalue) pairs in regs have not been formatted, but
+ * they are all in the same page and have been changed to being page
+ * relative. The page register has been written if that was neccessary.
+ */
+static int _regmap_raw_multi_reg_write(struct regmap *map,
+ const struct reg_default *regs,
+ size_t num_regs)
+{
+ int ret;
+ void *buf;
+ int i;
+ u8 *u8;
+ size_t val_bytes = map->format.val_bytes;
+ size_t reg_bytes = map->format.reg_bytes;
+ size_t pad_bytes = map->format.pad_bytes;
+ size_t pair_size = reg_bytes + pad_bytes + val_bytes;
+ size_t len = pair_size * num_regs;
+
+ buf = kzalloc(len, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ /* We have to linearise by hand. */
+
+ u8 = buf;
+
+ for (i = 0; i < num_regs; i++) {
+ int reg = regs[i].reg;
+ int val = regs[i].def;
+ trace_regmap_hw_write_start(map->dev, reg, 1);
+ map->format.format_reg(u8, reg, map->reg_shift);
+ u8 += reg_bytes + pad_bytes;
+ map->format.format_val(u8, val, 0);
+ u8 += val_bytes;
+ }
+ u8 = buf;
+ *u8 |= map->write_flag_mask;
+
+ ret = map->bus->write(map->bus_context, buf, len);
+
+ kfree(buf);
+
+ for (i = 0; i < num_regs; i++) {
+ int reg = regs[i].reg;
+ trace_regmap_hw_write_done(map->dev, reg, 1);
+ }
+ return ret;
+}
+
+static unsigned int _regmap_register_page(struct regmap *map,
+ unsigned int reg,
+ struct regmap_range_node *range)
+{
+ unsigned int win_page = (reg - range->range_min) / range->window_len;
+
+ return win_page;
+}
+
+static int _regmap_range_multi_paged_reg_write(struct regmap *map,
+ struct reg_default *regs,
+ size_t num_regs)
+{
+ int ret;
+ int i, n;
+ struct reg_default *base;
+ unsigned int this_page;
+ /*
+ * the set of registers are not neccessarily in order, but
+ * since the order of write must be preserved this algorithm
+ * chops the set each time the page changes
+ */
+ base = regs;
+ for (i = 0, n = 0; i < num_regs; i++, n++) {
+ unsigned int reg = regs[i].reg;
+ struct regmap_range_node *range;
+
+ range = _regmap_range_lookup(map, reg);
+ if (range) {
+ unsigned int win_page = _regmap_register_page(map, reg,
+ range);
+
+ if (i == 0)
+ this_page = win_page;
+ if (win_page != this_page) {
+ this_page = win_page;
+ ret = _regmap_raw_multi_reg_write(map, base, n);
+ if (ret != 0)
+ return ret;
+ base += n;
+ n = 0;
+ }
+ ret = _regmap_select_page(map, &base[n].reg, range, 1);
+ if (ret != 0)
+ return ret;
+ }
+ }
+ if (n > 0)
+ return _regmap_raw_multi_reg_write(map, base, n);
+ return 0;
+}
+
static int _regmap_multi_reg_write(struct regmap *map,
const struct reg_default *regs,
- int num_regs)
+ size_t num_regs)
{
- int i, ret;
+ 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;
+ }
+ 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 (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++) {
- if (regs[i].reg % map->reg_stride)
- return -EINVAL;
- ret = _regmap_write(map, regs[i].reg, regs[i].def);
- if (ret != 0) {
- dev_err(map->dev, "Failed to write %x = %x: %d\n",
- regs[i].reg, regs[i].def, ret);
+ unsigned int reg = regs[i].reg;
+ struct regmap_range_node *range;
+ range = _regmap_range_lookup(map, reg);
+ if (range) {
+ size_t len = sizeof(struct reg_default)*num_regs;
+ struct reg_default *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 0;
+ return _regmap_raw_multi_reg_write(map, regs, num_regs);
}
/*
* regmap_multi_reg_write(): Write multiple registers to the device
*
- * where the set of register are supplied in any order
+ * where the set of register,value pairs are supplied in any order,
+ * possibly not all in a single range.
*
* @map: Register map to write to
* @regs: Array of structures containing register,value to be written
* @num_regs: Number of registers to write
*
- * This function is intended to be used for writing a large block of data
- * atomically to the device in single transfer for those I2C client devices
- * that implement this alternative block write mode.
+ * The 'normal' block write mode will send ultimately send data on the
+ * target bus as R,V1,V2,V3,..,Vn where successively higer registers are
+ * addressed. However, this alternative block multi write mode will send
+ * the data as R1,V1,R2,V2,..,Rn,Vn on the target bus. The target device
+ * must of course support the mode.
*
- * A value of zero will be returned on success, a negative errno will
- * be returned in error cases.
+ * A value of zero will be returned on success, a negative errno will be
+ * returned in error cases.
*/
int regmap_multi_reg_write(struct regmap *map, const struct reg_default *regs,
int num_regs)