On Tue, 21 Jul 2015 21:53:00 +0200, Lars-Peter Clausen wrote:
There is currently a lot of code duplication in ASoC drivers regarding the reset handling of devices. This patch introduces a new generic reset function in the generic AC'97 framework that can be used to replace most the custom reset functions.
Signed-off-by: Lars-Peter Clausen lars@metafoo.de
Reviewed-by: Takashi Iwai tiwai@suse.de
One possible improvement would be to allow to pass id_mask=0 as the full bit, so that you don't have to define the mask 0xffffffff at each time.
thanks,
Takashi
include/sound/ac97_codec.h | 2 ++ sound/ac97_bus.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 64 insertions(+)
diff --git a/include/sound/ac97_codec.h b/include/sound/ac97_codec.h index 0e9d75b..74bc8547 100644 --- a/include/sound/ac97_codec.h +++ b/include/sound/ac97_codec.h @@ -584,6 +584,8 @@ static inline int snd_ac97_update_power(struct snd_ac97 *ac97, int reg, void snd_ac97_suspend(struct snd_ac97 *ac97); void snd_ac97_resume(struct snd_ac97 *ac97); #endif +int snd_ac97_reset(struct snd_ac97 *ac97, bool try_warm, unsigned int id,
- unsigned int id_mask);
/* quirk types */ enum { diff --git a/sound/ac97_bus.c b/sound/ac97_bus.c index 2b50cbe..55791a0 100644 --- a/sound/ac97_bus.c +++ b/sound/ac97_bus.c @@ -18,6 +18,68 @@ #include <sound/ac97_codec.h>
/*
- snd_ac97_check_id() - Reads and checks the vendor ID of the device
- @ac97: The AC97 device to check
- @id: The ID to compare to
- @id_mask: Mask that is applied to the device ID before comparing to @id
- If @id is 0 this function returns true if the read device vendor ID is
- a valid ID. If @id is non 0 this functions returns true if @id
- matches the read vendor ID. Otherwise the function returns false.
- */
+static bool snd_ac97_check_id(struct snd_ac97 *ac97, unsigned int id,
- unsigned int id_mask)
+{
- ac97->id = ac97->bus->ops->read(ac97, AC97_VENDOR_ID1) << 16;
- ac97->id |= ac97->bus->ops->read(ac97, AC97_VENDOR_ID2);
- if (ac97->id == 0x0 || ac97->id == 0xffffffff)
return false;- if (id != 0 && id != (ac97->id & id_mask))
return false;- return true;
+}
+/**
- snd_ac97_reset() - Reset AC'97 device
- @ac97: The AC'97 device to reset
- @try_warm: Try a warm reset first
- @id: Expected device vendor ID
- @id_mask: Mask that is applied to the device ID before comparing to @id
- This function resets the AC'97 device. If @try_warm is true the function
- first performs a warm reset. If the warm reset is successful the function
- returns 1. Otherwise or if @try_warm is false the function issues cold reset
- followed by a warm reset. If this is successful the function returns 0,
- otherwise a negative error code. If @id is 0 any valid device ID will be
- accepted, otherwise only the ID that matches @id and @id_mask is accepted.
- */
+int snd_ac97_reset(struct snd_ac97 *ac97, bool try_warm, unsigned int id,
- unsigned int id_mask)
+{
- struct snd_ac97_bus_ops *ops = ac97->bus->ops;
- if (try_warm && ops->warm_reset) {
ops->warm_reset(ac97);if (snd_ac97_check_id(ac97, id, id_mask))return 1;- }
- if (ops->reset)
ops->reset(ac97);- if (ops->warm_reset)
ops->warm_reset(ac97);- if (snd_ac97_check_id(ac97, id, id_mask))
return 0;- return -ENODEV;
+} +EXPORT_SYMBOL_GPL(snd_ac97_reset);
+/*
- Let drivers decide whether they want to support given codec from their
- probe method. Drivers have direct access to the struct snd_ac97
- structure and may decide based on the id field amongst other things.
-- 2.1.4