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author | Opensource [Anthony Olech] <anthony.olech.opensource@diasemi.com> | 2014-03-04 13:54:02 (GMT) |
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committer | Mark Brown <broonie@linaro.org> | 2014-03-10 17:09:32 (GMT) |
commit | e894c3f46c302716d2f156b1f3339e2f96ceb65c (patch) | |
tree | d051cf7865aa21b8af4dd6a921c71efde418cfa1 /drivers/base | |
parent | 1c18d2ca104c36fc2ce147cce053c62f61d2ea68 (diff) | |
download | linux-e894c3f46c302716d2f156b1f3339e2f96ceb65c.tar.xz |
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.h | 2 | ||||
-rw-r--r-- | drivers/base/regmap/regmap.c | 188 |
2 files changed, 174 insertions, 16 deletions
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h index 33414b1..7d13269 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 35ab7ba..c69bbc0 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) |