regmap: 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.

Change-Id: I578b88aceef495add0f527eec4e8c8b7c4a922cc
Signed-off-by: Anthony Olech <anthony.olech.opensource@diasemi.com>
Signed-off-by: Santosh Mardi <gsantosh@codeaurora.org>
This commit is contained in:
Santosh Mardi 2015-09-16 11:29:33 +05:30 committed by Laxminath Kasam
parent 453a266ef0
commit d6d7103607
3 changed files with 187 additions and 21 deletions

View file

@ -135,7 +135,8 @@ 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 */
};

View file

@ -440,6 +440,7 @@ 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;
@ -1319,41 +1320,203 @@ out:
}
EXPORT_SYMBOL_GPL(regmap_bulk_write);
static int _regmap_multi_reg_write(struct regmap *map,
const struct reg_default *regs,
int num_regs)
/*
* _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 necessary.
*/
static int _regmap_raw_multi_reg_write(struct regmap *map,
const struct reg_default *regs,
size_t num_regs)
{
int i, ret;
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++) {
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);
return ret;
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,
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;
}
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;
}
}
return 0;
WARN_ON(!map->bus);
for (i = 0; i < num_regs; i++) {
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 _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)

View file

@ -162,7 +162,9 @@ typedef void (*regmap_unlock)(void *);
* @use_single_rw: If set, converts the bulk read and write operations into
* a series of single read and write operations. This is useful
* for device that does not support bulk read and write.
*
* @can_multi_write: If set, the device supports the multi write mode of bulk
* write operations, if clear multi write requests will be
* split into individual write operations
* @cache_type: The actual cache type.
* @reg_defaults_raw: Power on reset values for registers (for use with
* register cache support).
@ -213,7 +215,7 @@ struct regmap_config {
u8 write_flag_mask;
bool use_single_rw;
bool can_multi_write;
enum regmap_endian reg_format_endian;
enum regmap_endian val_format_endian;