Re: [PATCH 2/2] iio: imu: mpu6050: Add support for vdd-supply regulator

[Jean-Baptiste Maneyrol <JManeyrol@invensense.com>]

Hello Stephan,

nice patch but I have an important concern.

We are calling the core_enable/disable_regulator functions when going into suspend and resume. With your changes, we are going to power down the chip when going into suspend and then power it up again. This way we will loose all already set configuration, like FSR, sampling rate, init values, ... The chip will not be able to work correctly anymore after a suspend-resume cycle.

You need to change the resume/suspend handlers to only disable/enable the vddio regulator, not the vdd one.

Thanks.

Best regards,
JB

From: Stephan Gerhold <stephan@gerhold.net>

Sent: Wednesday, November 6, 2019 19:35

To: Jonathan Cameron <jic23@kernel.org>

Cc: Hartmut Knaack <knaack.h@gmx.de>; Lars-Peter Clausen <lars@metafoo.de>; Peter Meerwald-Stadler <pmeerw@pmeerw.net>; Rob Herring <robh+dt@kernel.org>; Mark Rutland <mark.rutland@arm.com>; Linus Walleij <linus.walleij@linaro.org>; Brian Masney <masneyb@onstation.org>;
 Jonathan Marek <jonathan@marek.ca>; Jean-Baptiste Maneyrol <JManeyrol@invensense.com>; linux-iio@vger.kernel.org <linux-iio@vger.kernel.org>; devicetree@vger.kernel.org <devicetree@vger.kernel.org>; linux-kernel@vger.kernel.org <linux-kernel@vger.kernel.org>;
 Stephan Gerhold <stephan@gerhold.net>

Subject: [PATCH 2/2] iio: imu: mpu6050: Add support for vdd-supply regulator

 


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MPU6050 has two power supply pins: VDD and VLOGIC, but the mpu6050

only supports enabling one of them at the moment. In some cases,

they may need to be enabled separately.



Add an additional "vdd-supply", but keep the code simple by making

the driver use the regulator bulk API. This actually allows further

simplifying the code since regulator_bulk_* already logs the errors

for us.



Signed-off-by: Stephan Gerhold <stephan@gerhold.net>

---

 drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 30 +++++++---------------

 drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h  |  5 ++--

 2 files changed, 12 insertions(+), 23 deletions(-)



diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c

index 354030e9bed5..8e50dbcd730b 100644

--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c

+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c

@@ -1144,11 +1144,8 @@ static int inv_mpu_core_enable_regulator(struct inv_mpu6050_state *st)

 {

         int result;

 

-       result = regulator_enable(st->vddio_supply);

-       if (result) {

-               dev_err(regmap_get_device(st->map),

-                       "Failed to enable regulator: %d\n", result);

-       } else {

+       result = regulator_bulk_enable(ARRAY_SIZE(st->supplies), st->supplies);

+       if (result == 0) {

                 /* Give the device a little bit of time to start up. */

                 usleep_range(35000, 70000);

         }

@@ -1158,14 +1155,7 @@ static int inv_mpu_core_enable_regulator(struct inv_mpu6050_state *st)

 

 static int inv_mpu_core_disable_regulator(struct inv_mpu6050_state *st)

 {

-       int result;

-

-       result = regulator_disable(st->vddio_supply);

-       if (result)

-               dev_err(regmap_get_device(st->map),

-                       "Failed to disable regulator: %d\n", result);

-

-       return result;

+       return regulator_bulk_disable(ARRAY_SIZE(st->supplies), st->supplies);

 }

 

 static void inv_mpu_core_disable_regulator_action(void *_data)

@@ -1239,14 +1229,12 @@ int inv_mpu_core_probe(struct regmap *regmap, int irq, const char *name,

                 return -EINVAL;

         }

 

-       st->vddio_supply = devm_regulator_get(dev, "vddio");

-       if (IS_ERR(st->vddio_supply)) {

-               if (PTR_ERR(st->vddio_supply) != -EPROBE_DEFER)

-                       dev_err(dev, "Failed to get vddio regulator %d\n",

-                               (int)PTR_ERR(st->vddio_supply));

-

-               return PTR_ERR(st->vddio_supply);

-       }

+       st->supplies[0].supply = "vdd";

+       st->supplies[1].supply = "vddio";

+       result = devm_regulator_bulk_get(dev, ARRAY_SIZE(st->supplies),

+                                        st->supplies);

+       if (result)

+               return result;

 

         result = inv_mpu_core_enable_regulator(st);

         if (result)

diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h

index 52fcf45050a5..96cbd7f2b4b3 100644

--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h

+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h

@@ -12,6 +12,7 @@

 #include <linux/iio/iio.h>

 #include <linux/iio/buffer.h>

 #include <linux/regmap.h>

+#include <linux/regulator/consumer.h>

 #include <linux/iio/sysfs.h>

 #include <linux/iio/kfifo_buf.h>

 #include <linux/iio/trigger.h>

@@ -130,7 +131,7 @@ struct inv_mpu6050_hw {

  *  @chip_period:      chip internal period estimation (~1kHz).

  *  @it_timestamp:     timestamp from previous interrupt.

  *  @data_timestamp:   timestamp for next data sample.

- *  @vddio_supply      voltage regulator for the chip.

+ *  @supplies:         voltage regulators for the chip.

  *  @magn_disabled:     magnetometer disabled for backward compatibility reason.

  *  @magn_raw_to_gauss:        coefficient to convert mag raw value to Gauss.

  *  @magn_orient:       magnetometer sensor chip orientation if available.

@@ -154,7 +155,7 @@ struct inv_mpu6050_state {

         s64 chip_period;

         s64 it_timestamp;

         s64 data_timestamp;

-       struct regulator *vddio_supply;

+       struct regulator_bulk_data supplies[2];

         bool magn_disabled;

         s32 magn_raw_to_gauss[3];

         struct iio_mount_matrix magn_orient;

-- 

2.23.0