2023-03-20 18:02:28

by Lin, Meng-Bo

[permalink] [raw]
Subject: [PATCH v2 2/2] leds: aw2013: Add vddio regulator

Some LEDs controllers are used with external pull-up for the interrupt
line and the I2C lines, so we might need to enable a regulator to bring
the lines into usable state. Otherwise, this might cause spurious
interrupts and reading from I2C will fail.

Implement support for "vddio-supply" that is enabled by the aw2013 driver
so that the regulator gets enabled when needed.

Signed-off-by: Lin, Meng-Bo <[email protected]>
---
drivers/leds/leds-aw2013.c | 26 +++++++++++++++++---------
1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/leds/leds-aw2013.c b/drivers/leds/leds-aw2013.c
index 0b52fc9097c6..95f2f9bf95ee 100644
--- a/drivers/leds/leds-aw2013.c
+++ b/drivers/leds/leds-aw2013.c
@@ -62,7 +62,7 @@ struct aw2013_led {

struct aw2013 {
struct mutex mutex; /* held when writing to registers */
- struct regulator *vcc_regulator;
+ struct regulator_bulk_data regulators[2];
struct i2c_client *client;
struct aw2013_led leds[AW2013_MAX_LEDS];
struct regmap *regmap;
@@ -106,7 +106,8 @@ static void aw2013_chip_disable(struct aw2013 *chip)

regmap_write(chip->regmap, AW2013_GCR, 0);

- ret = regulator_disable(chip->vcc_regulator);
+ ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
+ chip->regulators);
if (ret) {
dev_err(&chip->client->dev,
"Failed to disable regulator: %d\n", ret);
@@ -123,7 +124,8 @@ static int aw2013_chip_enable(struct aw2013 *chip)
if (chip->enabled)
return 0;

- ret = regulator_enable(chip->vcc_regulator);
+ ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators),
+ chip->regulators);
if (ret) {
dev_err(&chip->client->dev,
"Failed to enable regulator: %d\n", ret);
@@ -348,16 +350,20 @@ static int aw2013_probe(struct i2c_client *client)
goto error;
}

- chip->vcc_regulator = devm_regulator_get(&client->dev, "vcc");
- ret = PTR_ERR_OR_ZERO(chip->vcc_regulator);
- if (ret) {
+ chip->regulators[0].supply = "vcc";
+ chip->regulators[1].supply = "vddio";
+ ret = devm_regulator_bulk_get(&client->dev,
+ ARRAY_SIZE(chip->regulators),
+ chip->regulators);
+ if (ret < 0) {
if (ret != -EPROBE_DEFER)
dev_err(&client->dev,
"Failed to request regulator: %d\n", ret);
goto error;
}

- ret = regulator_enable(chip->vcc_regulator);
+ ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators),
+ chip->regulators);
if (ret) {
dev_err(&client->dev,
"Failed to enable regulator: %d\n", ret);
@@ -382,7 +388,8 @@ static int aw2013_probe(struct i2c_client *client)
if (ret < 0)
goto error_reg;

- ret = regulator_disable(chip->vcc_regulator);
+ ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
+ chip->regulators);
if (ret) {
dev_err(&client->dev,
"Failed to disable regulator: %d\n", ret);
@@ -394,7 +401,8 @@ static int aw2013_probe(struct i2c_client *client)
return 0;

error_reg:
- regulator_disable(chip->vcc_regulator);
+ regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
+ chip->regulators);

error:
mutex_destroy(&chip->mutex);
--
2.30.2




2023-03-23 19:35:52

by Pavel Machek

[permalink] [raw]
Subject: Re: [PATCH v2 2/2] leds: aw2013: Add vddio regulator

Hi!

> Some LEDs controllers are used with external pull-up for the interrupt
> line and the I2C lines, so we might need to enable a regulator to bring
> the lines into usable state. Otherwise, this might cause spurious
> interrupts and reading from I2C will fail.
>
> Implement support for "vddio-supply" that is enabled by the aw2013 driver
> so that the regulator gets enabled when needed.
>
> Signed-off-by: Lin, Meng-Bo <[email protected]>

> @@ -348,16 +350,20 @@ static int aw2013_probe(struct i2c_client *client)
> goto error;
> }
>
> - chip->vcc_regulator = devm_regulator_get(&client->dev, "vcc");
> - ret = PTR_ERR_OR_ZERO(chip->vcc_regulator);
> - if (ret) {
> + chip->regulators[0].supply = "vcc";
> + chip->regulators[1].supply = "vddio";
> + ret = devm_regulator_bulk_get(&client->dev,
> + ARRAY_SIZE(chip->regulators),
> + chip->regulators);
> + if (ret < 0) {
> if (ret != -EPROBE_DEFER)
> dev_err(&client->dev,
> "Failed to request regulator: %d\n", ret);
> goto error;

Won't this cause failures when optional vddio is unavailable?

BR,
Pavel

--
People of Russia, stop Putin before his war on Ukraine escalates.


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2023-03-29 17:07:02

by Luca Weiss

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Subject: Re: [PATCH v2 2/2] leds: aw2013: Add vddio regulator

On Freitag, 24. M?rz 2023 09:32:52 CEST Stephan Gerhold wrote:
> Hi Pavel,
>
> On Thu, Mar 23, 2023 at 08:35:02PM +0100, Pavel Machek wrote:
> > > Some LEDs controllers are used with external pull-up for the interrupt
> > > line and the I2C lines, so we might need to enable a regulator to bring
> > > the lines into usable state. Otherwise, this might cause spurious
> > > interrupts and reading from I2C will fail.
> > >
> > > Implement support for "vddio-supply" that is enabled by the aw2013
> > > driver
> > > so that the regulator gets enabled when needed.
> > >
> > > Signed-off-by: Lin, Meng-Bo <[email protected]>
> > >
> > > @@ -348,16 +350,20 @@ static int aw2013_probe(struct i2c_client *client)
> > >
> > > goto error;
> > >
> > > }
> > >
> > > - chip->vcc_regulator = devm_regulator_get(&client->dev, "vcc");
> > > - ret = PTR_ERR_OR_ZERO(chip->vcc_regulator);
> > > - if (ret) {
> > > + chip->regulators[0].supply = "vcc";
> > > + chip->regulators[1].supply = "vddio";
> > > + ret = devm_regulator_bulk_get(&client->dev,
> > > + ARRAY_SIZE(chip->regulators),
> > > + chip->regulators);
> > > + if (ret < 0) {
> > >
> > > if (ret != -EPROBE_DEFER)
> > >
> > > dev_err(&client->dev,
> > >
> > > "Failed to request regulator: %d\n",
ret);
> > >
> > > goto error;
> >
> > Won't this cause failures when optional vddio is unavailable?
>
> The regulator core should print a warning "supply vddio not found, using
> dummy regulator" but then proceed normally.
>
> I think in almost all cases a separate I/O supply should actually exist
> that could be described in the device tree. It was likely just omitted
> because it's always-on or indirectly being enabled by other devices.
> So perhaps having this warning is even a good thing?

Just briefly jumping in, there was some activity adding bus_regulator to the
i2c-core a while back, maybe that can be revived instead? For CCI (camera i2c)
we also need pull-ups and I don't think adding vddio or whatever to all
sensors is a good idea long term...

https://lore.kernel.org/lkml/[email protected]/

Regards
Luca

>
> Thanks,
> Stephan