[PATCH V2 1/4] regmap: cache: Add "was_reset" argument to regcache_sync_region()
From: Kevin Cernekee
Date: Fri Apr 24 2015 - 18:37:17 EST
regcache_sync() and regcache_sync_region() currently assume that the
hardware has just emerged from a clean reset, and that all registers are
in their default states. But that isn't the only possibility; the device
may have been in a different state in which the registers were
inaccessible but have retained their contents, e.g. clock gating.
So we will extend the more versatile of the two functions,
regcache_sync_region(), to let the caller decide what assumptions should
be made.
One driver that can benefit from this is adau1977, which has hacks to
overwrite the registers that regcache_sync() might have missed. Also,
the powerdown pin on tas571x does not reset the register contents either,
so a similar feature will be required by that driver.
This commit just adds the new argument by changing the function
declarations and call sites, but doesn't wire it up yet.
Signed-off-by: Kevin Cernekee <cernekee@xxxxxxxxxxxx>
---
drivers/base/regmap/internal.h | 5 ++-
drivers/base/regmap/regcache-lzo.c | 2 +-
drivers/base/regmap/regcache-rbtree.c | 5 ++-
drivers/base/regmap/regcache.c | 75 ++++++++++++++++++++---------------
drivers/media/radio/radio-si476x.c | 18 ++++++---
drivers/mfd/wm8994-core.c | 5 ++-
include/linux/regmap.h | 4 +-
include/sound/hda_regmap.h | 3 +-
sound/soc/codecs/wm8962.c | 3 +-
9 files changed, 72 insertions(+), 48 deletions(-)
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index a13587b5c2be..89dfefeb168e 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -155,7 +155,8 @@ struct regcache_ops {
#endif
int (*read)(struct regmap *map, unsigned int reg, unsigned int *value);
int (*write)(struct regmap *map, unsigned int reg, unsigned int value);
- int (*sync)(struct regmap *map, unsigned int min, unsigned int max);
+ int (*sync)(struct regmap *map, unsigned int min, unsigned int max,
+ bool was_reset);
int (*drop)(struct regmap *map, unsigned int min, unsigned int max);
};
@@ -215,7 +216,7 @@ int regcache_sync(struct regmap *map);
int regcache_sync_block(struct regmap *map, void *block,
unsigned long *cache_present,
unsigned int block_base, unsigned int start,
- unsigned int end);
+ unsigned int end, bool was_reset);
static inline const void *regcache_get_val_addr(struct regmap *map,
const void *base,
diff --git a/drivers/base/regmap/regcache-lzo.c b/drivers/base/regmap/regcache-lzo.c
index 2d53f6f138e1..52ed0d03ce69 100644
--- a/drivers/base/regmap/regcache-lzo.c
+++ b/drivers/base/regmap/regcache-lzo.c
@@ -332,7 +332,7 @@ out:
}
static int regcache_lzo_sync(struct regmap *map, unsigned int min,
- unsigned int max)
+ unsigned int max, bool was_reset)
{
struct regcache_lzo_ctx **lzo_blocks;
unsigned int val;
diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
index 81751a49d8bf..8fc1727e635c 100644
--- a/drivers/base/regmap/regcache-rbtree.c
+++ b/drivers/base/regmap/regcache-rbtree.c
@@ -445,7 +445,7 @@ static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
}
static int regcache_rbtree_sync(struct regmap *map, unsigned int min,
- unsigned int max)
+ unsigned int max, bool was_reset)
{
struct regcache_rbtree_ctx *rbtree_ctx;
struct rb_node *node;
@@ -477,7 +477,8 @@ static int regcache_rbtree_sync(struct regmap *map, unsigned int min,
ret = regcache_sync_block(map, rbnode->block,
rbnode->cache_present,
- rbnode->base_reg, start, end);
+ rbnode->base_reg, start, end,
+ was_reset);
if (ret != 0)
return ret;
}
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 7eb7b3b98794..d27b45f50497 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -250,7 +250,7 @@ int regcache_write(struct regmap *map,
}
static int regcache_default_sync(struct regmap *map, unsigned int min,
- unsigned int max)
+ unsigned int max, bool was_reset)
{
unsigned int reg;
@@ -266,10 +266,12 @@ static int regcache_default_sync(struct regmap *map, unsigned int min,
if (ret)
return ret;
- /* Is this the hardware default? If so skip. */
- ret = regcache_lookup_reg(map, reg);
- if (ret >= 0 && val == map->reg_defaults[ret].def)
- continue;
+ if (was_reset) {
+ /* Is this the hardware default? If so skip. */
+ ret = regcache_lookup_reg(map, reg);
+ if (ret >= 0 && val == map->reg_defaults[ret].def)
+ continue;
+ }
map->cache_bypass = 1;
ret = _regmap_write(map, reg, val);
@@ -294,6 +296,10 @@ static int regcache_default_sync(struct regmap *map, unsigned int min,
* volatile. In general drivers can choose not to use the provided
* syncing functionality if they so require.
*
+ * This assumes that the hardware registers contain their default values.
+ * If the cached value matches the default value for a register, the write
+ * operation will be skipped.
+ *
* Return a negative value on failure, 0 on success.
*/
int regcache_sync(struct regmap *map)
@@ -331,9 +337,9 @@ int regcache_sync(struct regmap *map)
map->cache_bypass = 0;
if (map->cache_ops->sync)
- ret = map->cache_ops->sync(map, 0, map->max_register);
+ ret = map->cache_ops->sync(map, 0, map->max_register, true);
else
- ret = regcache_default_sync(map, 0, map->max_register);
+ ret = regcache_default_sync(map, 0, map->max_register, true);
if (ret == 0)
map->cache_dirty = false;
@@ -353,19 +359,18 @@ out:
EXPORT_SYMBOL_GPL(regcache_sync);
/**
- * regcache_sync_region: Sync part of the register cache with the hardware.
+ * regcache_sync_region: Sync part of the register cache with the hardware.
*
* @map: map to sync.
* @min: first register to sync
* @max: last register to sync
- *
- * Write all non-default register values in the specified region to
- * the hardware.
+ * @was_reset: true if the hardware is known to contain default register values
+ * in the given range; false otherwise
*
* Return a negative value on failure, 0 on success.
*/
int regcache_sync_region(struct regmap *map, unsigned int min,
- unsigned int max)
+ unsigned int max, bool was_reset)
{
int ret = 0;
const char *name;
@@ -389,9 +394,9 @@ int regcache_sync_region(struct regmap *map, unsigned int min,
map->async = true;
if (map->cache_ops->sync)
- ret = map->cache_ops->sync(map, min, max);
+ ret = map->cache_ops->sync(map, min, max, was_reset);
else
- ret = regcache_default_sync(map, min, max);
+ ret = regcache_default_sync(map, min, max, was_reset);
out:
/* Restore the bypass state */
@@ -600,7 +605,8 @@ static bool regcache_reg_present(unsigned long *cache_present, unsigned int idx)
static int regcache_sync_block_single(struct regmap *map, void *block,
unsigned long *cache_present,
unsigned int block_base,
- unsigned int start, unsigned int end)
+ unsigned int start, unsigned int end,
+ bool was_reset)
{
unsigned int i, regtmp, val;
int ret;
@@ -614,10 +620,12 @@ static int regcache_sync_block_single(struct regmap *map, void *block,
val = regcache_get_val(map, block, i);
- /* Is this the hardware default? If so skip. */
- ret = regcache_lookup_reg(map, regtmp);
- if (ret >= 0 && val == map->reg_defaults[ret].def)
- continue;
+ if (was_reset) {
+ /* Is this the hardware default? If so skip. */
+ ret = regcache_lookup_reg(map, regtmp);
+ if (ret >= 0 && val == map->reg_defaults[ret].def)
+ continue;
+ }
map->cache_bypass = 1;
@@ -667,7 +675,7 @@ static int regcache_sync_block_raw_flush(struct regmap *map, const void **data,
static int regcache_sync_block_raw(struct regmap *map, void *block,
unsigned long *cache_present,
unsigned int block_base, unsigned int start,
- unsigned int end)
+ unsigned int end, bool was_reset)
{
unsigned int i, val;
unsigned int regtmp = 0;
@@ -689,14 +697,17 @@ static int regcache_sync_block_raw(struct regmap *map, void *block,
val = regcache_get_val(map, block, i);
- /* Is this the hardware default? If so skip. */
- ret = regcache_lookup_reg(map, regtmp);
- if (ret >= 0 && val == map->reg_defaults[ret].def) {
- ret = regcache_sync_block_raw_flush(map, &data,
- base, regtmp);
- if (ret != 0)
- return ret;
- continue;
+ if (was_reset) {
+ /* Is this the hardware default? If so skip. */
+ ret = regcache_lookup_reg(map, regtmp);
+ if (ret >= 0 && val == map->reg_defaults[ret].def) {
+ ret = regcache_sync_block_raw_flush(map, &data,
+ base,
+ regtmp);
+ if (ret != 0)
+ return ret;
+ continue;
+ }
}
if (!data) {
@@ -712,12 +723,14 @@ static int regcache_sync_block_raw(struct regmap *map, void *block,
int regcache_sync_block(struct regmap *map, void *block,
unsigned long *cache_present,
unsigned int block_base, unsigned int start,
- unsigned int end)
+ unsigned int end, bool was_reset)
{
if (regmap_can_raw_write(map) && !map->use_single_rw)
return regcache_sync_block_raw(map, block, cache_present,
- block_base, start, end);
+ block_base, start, end,
+ was_reset);
else
return regcache_sync_block_single(map, block, cache_present,
- block_base, start, end);
+ block_base, start, end,
+ was_reset);
}
diff --git a/drivers/media/radio/radio-si476x.c b/drivers/media/radio/radio-si476x.c
index dccf58691650..ff4785f0416d 100644
--- a/drivers/media/radio/radio-si476x.c
+++ b/drivers/media/radio/radio-si476x.c
@@ -567,19 +567,22 @@ static int si476x_radio_do_post_powerup_init(struct si476x_radio *radio,
/* regcache_mark_dirty(radio->core->regmap); */
err = regcache_sync_region(radio->core->regmap,
SI476X_PROP_DIGITAL_IO_INPUT_SAMPLE_RATE,
- SI476X_PROP_DIGITAL_IO_OUTPUT_FORMAT);
+ SI476X_PROP_DIGITAL_IO_OUTPUT_FORMAT,
+ true);
if (err < 0)
return err;
err = regcache_sync_region(radio->core->regmap,
SI476X_PROP_AUDIO_DEEMPHASIS,
- SI476X_PROP_AUDIO_PWR_LINE_FILTER);
+ SI476X_PROP_AUDIO_PWR_LINE_FILTER,
+ true);
if (err < 0)
return err;
err = regcache_sync_region(radio->core->regmap,
SI476X_PROP_INT_CTL_ENABLE,
- SI476X_PROP_INT_CTL_ENABLE);
+ SI476X_PROP_INT_CTL_ENABLE,
+ true);
if (err < 0)
return err;
@@ -589,13 +592,15 @@ static int si476x_radio_do_post_powerup_init(struct si476x_radio *radio,
*/
err = regcache_sync_region(radio->core->regmap,
SI476X_PROP_VALID_MAX_TUNE_ERROR,
- SI476X_PROP_VALID_MAX_TUNE_ERROR);
+ SI476X_PROP_VALID_MAX_TUNE_ERROR,
+ true);
if (err < 0)
return err;
err = regcache_sync_region(radio->core->regmap,
SI476X_PROP_VALID_SNR_THRESHOLD,
- SI476X_PROP_VALID_RSSI_THRESHOLD);
+ SI476X_PROP_VALID_RSSI_THRESHOLD,
+ true);
if (err < 0)
return err;
@@ -609,7 +614,8 @@ static int si476x_radio_do_post_powerup_init(struct si476x_radio *radio,
err = regcache_sync_region(radio->core->regmap,
SI476X_PROP_FM_RDS_INTERRUPT_SOURCE,
- SI476X_PROP_FM_RDS_CONFIG);
+ SI476X_PROP_FM_RDS_CONFIG,
+ true);
if (err < 0)
return err;
}
diff --git a/drivers/mfd/wm8994-core.c b/drivers/mfd/wm8994-core.c
index 53ae5af5d6e4..d5632634a362 100644
--- a/drivers/mfd/wm8994-core.c
+++ b/drivers/mfd/wm8994-core.c
@@ -158,14 +158,15 @@ static int wm8994_suspend(struct device *dev)
* pin configurations.
*/
ret = regcache_sync_region(wm8994->regmap, WM8994_GPIO_1,
- WM8994_GPIO_11);
+ WM8994_GPIO_11, true);
if (ret != 0)
dev_err(dev, "Failed to restore GPIO registers: %d\n", ret);
/* In case one of the GPIOs is used as a wake input. */
ret = regcache_sync_region(wm8994->regmap,
WM8994_INTERRUPT_STATUS_1_MASK,
- WM8994_INTERRUPT_STATUS_1_MASK);
+ WM8994_INTERRUPT_STATUS_1_MASK,
+ true);
if (ret != 0)
dev_err(dev, "Failed to restore interrupt mask: %d\n", ret);
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 116655d92269..ece122a6fdeb 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -438,7 +438,7 @@ bool regmap_can_raw_write(struct regmap *map);
int regcache_sync(struct regmap *map);
int regcache_sync_region(struct regmap *map, unsigned int min,
- unsigned int max);
+ unsigned int max, bool was_reset);
int regcache_drop_region(struct regmap *map, unsigned int min,
unsigned int max);
void regcache_cache_only(struct regmap *map, bool enable);
@@ -683,7 +683,7 @@ static inline int regcache_sync(struct regmap *map)
}
static inline int regcache_sync_region(struct regmap *map, unsigned int min,
- unsigned int max)
+ unsigned int max, bool was_reset)
{
WARN_ONCE(1, "regmap API is disabled");
return -EINVAL;
diff --git a/include/sound/hda_regmap.h b/include/sound/hda_regmap.h
index 53a18b3635e2..f6bb68137ca4 100644
--- a/include/sound/hda_regmap.h
+++ b/include/sound/hda_regmap.h
@@ -211,7 +211,8 @@ static inline void
snd_hdac_regmap_sync_node(struct hdac_device *codec, hda_nid_t nid)
{
regcache_mark_dirty(codec->regmap);
- regcache_sync_region(codec->regmap, nid << 20, ((nid + 1) << 20) - 1);
+ regcache_sync_region(codec->regmap, nid << 20,
+ ((nid + 1) << 20) - 1, true);
}
#endif /* __SOUND_HDA_REGMAP_H */
diff --git a/sound/soc/codecs/wm8962.c b/sound/soc/codecs/wm8962.c
index 118b0034ba23..3a25d2d93705 100644
--- a/sound/soc/codecs/wm8962.c
+++ b/sound/soc/codecs/wm8962.c
@@ -1483,7 +1483,8 @@ static int wm8962_dsp2_write_config(struct snd_soc_codec *codec)
struct wm8962_priv *wm8962 = snd_soc_codec_get_drvdata(codec);
return regcache_sync_region(wm8962->regmap,
- WM8962_HDBASS_AI_1, WM8962_MAX_REGISTER);
+ WM8962_HDBASS_AI_1, WM8962_MAX_REGISTER,
+ true);
}
static int wm8962_dsp2_set_enable(struct snd_soc_codec *codec, u16 val)
--
2.2.0.rc0.207.ga3a616c
--
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