On Mon, Nov 28, 2016 at 05:32:26PM +0000, Richard Fitzgerald wrote:
It's often the case that a codec driver will need to control its own pins. However, if a name_prefix has been applied to this codec it must be included in the name passed to any of the snd_soc_dapm_x_pin() functions.
The behaviour of the existing pin control functions is reasonable, since you may want to search for a fully-specified name within the scope of an entire card. This means that we can't apply the prefix in these functions because it will break card-scope searches.
Constructing a prefixed string "manually" in codec drivers leads to a lot of repetition of the same code.
To make this tidier in codec drivers this patch adds a new set of equivalent functions that take a struct snd_soc_component instead of a dapm context and automatically add the component's name_prefix to the given name. This makes it a simple change in codec drivers to be prefix-safe.
The new functions are not quite trivial enough to be inlines and the compiler won't be able to compile-away any part of them.
Although it looks somewhat inefficient to have to allocate a temporary buffer and combine strings, the current design of the widget list doesn't lend itself to a more optimized implementation - it's a single list of all widgets on a card and is searched linearly for a matching string. As pin state changes are generally low-frequency events it's unlikely to be a significant issue - at least not enough to rewrite the widget list handling just for this.
Signed-off-by: Richard Fitzgerald rf@opensource.wolfsonmicro.com
include/sound/soc.h | 25 +++++++ sound/soc/soc-utils.c | 199 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 224 insertions(+)
diff --git a/include/sound/soc.h b/include/sound/soc.h index 795e6c4..a46d0774 100644 --- a/include/sound/soc.h +++ b/include/sound/soc.h @@ -1718,4 +1718,29 @@ static inline void snd_soc_dapm_mutex_unlock(struct snd_soc_dapm_context *dapm) mutex_unlock(&dapm->card->dapm_mutex); }
+extern int snd_soc_component_enable_pin(struct snd_soc_component *component,
const char *pin);+extern int snd_soc_component_enable_pin_unlocked(
struct snd_soc_component *component,const char *pin);+extern int snd_soc_component_disable_pin(struct snd_soc_component *component,
const char *pin);+extern int snd_soc_component_disable_pin_unlocked(
struct snd_soc_component *component,const char *pin);+extern int snd_soc_component_nc_pin(struct snd_soc_component *component,
const char *pin);+extern int snd_soc_component_nc_pin_unlocked(
struct snd_soc_component *component,const char *pin);+extern int snd_soc_component_get_pin_status(struct snd_soc_component *component,
const char *pin);+extern int snd_soc_component_force_enable_pin(
struct snd_soc_component *component,const char *pin);+extern int snd_soc_component_force_enable_pin_unlocked(
struct snd_soc_component *component,const char *pin);
I don't believe we need these extern's C defaults to external linkage.
Thanks, Charles