Re: [PATCH 1/2] extcon: arizona: Deobfuscate arizona_extcon_do_magic

Lee Jones
2015-02-16T16:50:13Z

On Mon, 16 Feb 2015, Charles Keepax wrote:

> arizona_extcon_do_magic does not lend a lot of clarity to the purpose
> of the function, and as all the registers used are described in the
> datasheet there is no need to obfuscate the code. This patch renames the
> function to arizona_extcon_hp_clamp, as it controls clamping on the
> headphone output.
>
> Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
> ---
> drivers/extcon/extcon-arizona.c | 36 ++++++++++++++++++++----------------
> include/linux/mfd/arizona/core.h | 2 +-

Acked-by: Lee Jones <lee.jones@linaro.org>

> sound/soc/codecs/arizona.c | 4 ++--
> 3 files changed, 23 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/extcon/extcon-arizona.c b/drivers/extcon/extcon-arizona.c
> index 63f01c4..95cf7f8 100644
> --- a/drivers/extcon/extcon-arizona.c
> +++ b/drivers/extcon/extcon-arizona.c
> @@ -136,18 +136,22 @@ static const char *arizona_cable[] = {
>
> static void arizona_start_hpdet_acc_id(struct arizona_extcon_info *info);
>
> -static void arizona_extcon_do_magic(struct arizona_extcon_info *info,
> - unsigned int magic)
> +static void arizona_extcon_hp_clamp(struct arizona_extcon_info *info,
> + bool clamp)
> {
> struct arizona *arizona = info->arizona;
> + unsigned int val = 0;
> int ret;
>
> + if (clamp)
> + val = ARIZONA_RMV_SHRT_HP1L;
> +
> mutex_lock(&arizona->dapm->card->dapm_mutex);
>
> - arizona->hpdet_magic = magic;
> + arizona->hpdet_clamp = clamp;
>
> - /* Keep the HP output stages disabled while doing the magic */
> - if (magic) {
> + /* Keep the HP output stages disabled while doing the clamp */
> + if (clamp) {
> ret = regmap_update_bits(arizona->regmap,
> ARIZONA_OUTPUT_ENABLES_1,
> ARIZONA_OUT1L_ENA |
> @@ -158,20 +162,20 @@ static void arizona_extcon_do_magic(struct arizona_extcon_info *info,
> ret);
> }
>
> - ret = regmap_update_bits(arizona->regmap, 0x225, 0x4000,
> - magic);
> + ret = regmap_update_bits(arizona->regmap, ARIZONA_HP_CTRL_1L,
> + ARIZONA_RMV_SHRT_HP1L, val);
> if (ret != 0)
> - dev_warn(arizona->dev, "Failed to do magic: %d\n",
> + dev_warn(arizona->dev, "Failed to do clamp: %d\n",
> ret);
>
> - ret = regmap_update_bits(arizona->regmap, 0x226, 0x4000,
> - magic);
> + ret = regmap_update_bits(arizona->regmap, ARIZONA_HP_CTRL_1R,
> + ARIZONA_RMV_SHRT_HP1R, val);
> if (ret != 0)
> - dev_warn(arizona->dev, "Failed to do magic: %d\n",
> + dev_warn(arizona->dev, "Failed to do clamp: %d\n",
> ret);
>
> - /* Restore the desired state while not doing the magic */
> - if (!magic) {
> + /* Restore the desired state while not doing the clamp */
> + if (!clamp) {
> ret = regmap_update_bits(arizona->regmap,
> ARIZONA_OUTPUT_ENABLES_1,
> ARIZONA_OUT1L_ENA |
> @@ -603,7 +607,7 @@ done:
> ARIZONA_HP_IMPEDANCE_RANGE_MASK | ARIZONA_HP_POLL,
> 0);
>
> - arizona_extcon_do_magic(info, 0);
> + arizona_extcon_hp_clamp(info, false);
>
> if (id_gpio)
> gpio_set_value_cansleep(id_gpio, 0);
> @@ -648,7 +652,7 @@ static void arizona_identify_headphone(struct arizona_extcon_info *info)
> if (info->mic)
> arizona_stop_mic(info);
>
> - arizona_extcon_do_magic(info, 0x4000);
> + arizona_extcon_hp_clamp(info, true);
>
> ret = regmap_update_bits(arizona->regmap,
> ARIZONA_ACCESSORY_DETECT_MODE_1,
> @@ -699,7 +703,7 @@ static void arizona_start_hpdet_acc_id(struct arizona_extcon_info *info)
>
> info->hpdet_active = true;
>
> - arizona_extcon_do_magic(info, 0x4000);
> + arizona_extcon_hp_clamp(info, true);
>
> ret = regmap_update_bits(arizona->regmap,
> ARIZONA_ACCESSORY_DETECT_MODE_1,
> diff --git a/include/linux/mfd/arizona/core.h b/include/linux/mfd/arizona/core.h
> index 910e3aa..4863548 100644
> --- a/include/linux/mfd/arizona/core.h
> +++ b/include/linux/mfd/arizona/core.h
> @@ -126,7 +126,7 @@ struct arizona {
> struct regmap_irq_chip_data *aod_irq_chip;
> struct regmap_irq_chip_data *irq_chip;
>
> - bool hpdet_magic;
> + bool hpdet_clamp;
> unsigned int hp_ena;
>
> struct mutex clk_lock;
> diff --git a/sound/soc/codecs/arizona.c b/sound/soc/codecs/arizona.c
> index 9550d74..a6e5c70 100644
> --- a/sound/soc/codecs/arizona.c
> +++ b/sound/soc/codecs/arizona.c
> @@ -780,8 +780,8 @@ int arizona_hp_ev(struct snd_soc_dapm_widget *w,
> priv->arizona->hp_ena &= ~mask;
> priv->arizona->hp_ena |= val;
>
> - /* Force off if HPDET magic is active */
> - if (priv->arizona->hpdet_magic)
> + /* Force off if HPDET clamp is active */
> + if (priv->arizona->hpdet_clamp)
> val = 0;
>
> regmap_update_bits_async(arizona->regmap, ARIZONA_OUTPUT_ENABLES_1,

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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