Hi Mark, Do you have any concern about this patch ?
Thanks! On Thu, Sep 13, 2018 at 12:47 AM Rohit Kumar rohitkr@codeaurora.org wrote:
On 9/12/2018 5:49 PM, Cheng-Yi Chiang wrote:
Toggle reset line in max98927_i2c_probe. Use a list to store max98927 instances so we do not toggle reset line again if more than one instances share the same reset line.
Signed-off-by: Cheng-Yi Chiang cychiang@chromium.org
Reviewed-and-tested-by: Rohit kumar rohitkr@codeaurora.org
sound/soc/codecs/max98927.c | 78 +++++++++++++++++++++++++++++++++++++++++++++ sound/soc/codecs/max98927.h | 2 ++ 2 files changed, 80 insertions(+)
diff --git a/sound/soc/codecs/max98927.c b/sound/soc/codecs/max98927.c index 941712058a8f5..789b27cdfd9e0 100644 --- a/sound/soc/codecs/max98927.c +++ b/sound/soc/codecs/max98927.c @@ -11,6 +11,7 @@ */
#include <linux/acpi.h> +#include <linux/delay.h> #include <linux/i2c.h> #include <linux/module.h> #include <linux/regmap.h> @@ -24,6 +25,11 @@ #include <sound/tlv.h> #include "max98927.h"
+#define MAX98927_MIN_RESET_US 1 +#define MAX98927_RELEASE_RESET_DELAY_US 500
+static LIST_HEAD(reset_list);
- static struct reg_default max98927_reg[] = { {MAX98927_R0001_INT_RAW1, 0x00}, {MAX98927_R0002_INT_RAW2, 0x00},
@@ -877,6 +883,54 @@ static void max98927_slot_config(struct i2c_client *i2c, max98927->i_l_slot = 1; }
+static int max98927_i2c_toggle_reset(struct device *dev,
struct max98927_priv *max98927)+{
/** If we do not have reset gpio, assume platform firmware* controls the regulator and toggles it for us.*/if (!max98927->reset_gpio)return 0;gpiod_set_value_cansleep(max98927->reset_gpio, 1);/** We need to wait a bit before we are allowed to release reset GPIO.*/usleep_range(MAX98927_MIN_RESET_US, MAX98927_MIN_RESET_US + 5);gpiod_set_value_cansleep(max98927->reset_gpio, 0);/** We need to wait a bit before I2C communication is available.*/usleep_range(MAX98927_RELEASE_RESET_DELAY_US,MAX98927_RELEASE_RESET_DELAY_US + 5);/** Release reset GPIO because we are not going to use it.*/devm_gpiod_put(dev, max98927->reset_gpio);return 0;+}
+static bool max98927_is_first_to_reset(struct max98927_priv *max98927) +{
struct max98927_priv *p;if (!max98927->reset_gpio)return false;list_for_each_entry(p, &reset_list, list) {if (max98927->reset_gpio == p->reset_gpio)return false;}return true;+}
- static int max98927_i2c_probe(struct i2c_client *i2c, const struct i2c_device_id *id) {
@@ -904,6 +958,28 @@ static int max98927_i2c_probe(struct i2c_client *i2c, } else max98927->interleave_mode = 0;
/* Gets optional GPIO for reset line. */max98927->reset_gpio = devm_gpiod_get_optional(&i2c->dev, "reset", GPIOD_OUT_LOW);if (IS_ERR(max98927->reset_gpio)) {ret = PTR_ERR(max98927->reset_gpio);dev_err(&i2c->dev, "error getting reset gpio: %d\n", ret);return ret;}/** Only toggle reset line for the first instance when the* reset line is shared among instances. For example,* left and right amplifier share the same reset line, and* we should only toggle the reset line once.*/if (max98927_is_first_to_reset(max98927)) {dev_info(&i2c->dev, "%s: toggle reset line\n", __func__);ret = max98927_i2c_toggle_reset(&i2c->dev, max98927);if (ret)return ret;}/* regmap initialization */ max98927->regmap = devm_regmap_init_i2c(i2c, &max98927_regmap);@@ -934,6 +1010,8 @@ static int max98927_i2c_probe(struct i2c_client *i2c, if (ret < 0) dev_err(&i2c->dev, "Failed to register component: %d\n", ret);
list_add(&max98927->list, &reset_list);return ret;diff --git a/sound/soc/codecs/max98927.h b/sound/soc/codecs/max98927.h index 538992a238b28..d48f61f6c3ba5 100644 --- a/sound/soc/codecs/max98927.h +++ b/sound/soc/codecs/max98927.h @@ -275,5 +275,7 @@ struct max98927_priv { unsigned int master; unsigned int digital_gain; bool tdm_mode;
struct gpio_desc *reset_gpio;struct list_head list;