* [PATCH v7 5/5] iio: magnetometer: ak8975: Add gpio reset support
@ 2020-05-28 15:01 Jonathan Albrieux
2020-05-31 11:02 ` Jonathan Cameron
0 siblings, 1 reply; 3+ messages in thread
From: Jonathan Albrieux @ 2020-05-28 15:01 UTC (permalink / raw)
To: linux-kernel
Cc: ~postmarketos/upstreaming, Jonathan Albrieux, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald-Stadler,
Andy Shevchenko, Linus Walleij,
open list:IIO SUBSYSTEM AND DRIVERS
According to AK09911 datasheet, if reset gpio is provided then
deassert reset on ak8975_power_on() and assert reset on ak8975_power_off().
Without reset's deassertion during ak8975_power_on(), driver's probe fails
on ak8975_who_i_am() while checking for device identity for AK09911 chip.
AK09911 has an active low reset gpio to handle register's reset.
AK09911 datasheet says that, if not used, reset pin should be connected
to VID. This patch emulates this situation.
Signed-off-by: Jonathan Albrieux <jonathan.albrieux@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Stephan Gerhold <stephan@gerhold.net>
---
drivers/iio/magnetometer/ak8975.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index fd368455cd7b..a23422aad97d 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -358,6 +358,7 @@ struct ak8975_data {
u8 asa[3];
long raw_to_gauss[3];
struct gpio_desc *eoc_gpiod;
+ struct gpio_desc *reset_gpiod;
int eoc_irq;
wait_queue_head_t data_ready_queue;
unsigned long flags;
@@ -384,6 +385,9 @@ static int ak8975_power_on(const struct ak8975_data *data)
"Failed to enable specified Vid supply\n");
return ret;
}
+
+ gpiod_set_value_cansleep(data->reset_gpiod, 0);
+
/*
* According to the datasheet the power supply rise time is 200us
* and the minimum wait time before mode setting is 100us, in
@@ -396,6 +400,8 @@ static int ak8975_power_on(const struct ak8975_data *data)
/* Disable attached power regulator if any. */
static void ak8975_power_off(const struct ak8975_data *data)
{
+ gpiod_set_value_cansleep(data->reset_gpiod, 1);
+
regulator_disable(data->vid);
regulator_disable(data->vdd);
}
@@ -839,6 +845,7 @@ static int ak8975_probe(struct i2c_client *client,
struct ak8975_data *data;
struct iio_dev *indio_dev;
struct gpio_desc *eoc_gpiod;
+ struct gpio_desc *reset_gpiod;
const void *match;
unsigned int i;
int err;
@@ -856,6 +863,16 @@ static int ak8975_probe(struct i2c_client *client,
if (eoc_gpiod)
gpiod_set_consumer_name(eoc_gpiod, "ak_8975");
+ /*
+ * According to AK09911 datasheet, if reset GPIO is provided then
+ * deassert reset on ak8975_power_on() and assert reset on
+ * ak8975_power_off().
+ */
+ reset_gpiod = devm_gpiod_get_optional(&client->dev,
+ "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(reset_gpiod))
+ return PTR_ERR(reset_gpiod);
+
/* Register with IIO */
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (indio_dev == NULL)
@@ -866,6 +883,7 @@ static int ak8975_probe(struct i2c_client *client,
data->client = client;
data->eoc_gpiod = eoc_gpiod;
+ data->reset_gpiod = reset_gpiod;
data->eoc_irq = 0;
err = iio_read_mount_matrix(&client->dev, "mount-matrix", &data->orientation);
--
2.17.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v7 5/5] iio: magnetometer: ak8975: Add gpio reset support
2020-05-28 15:01 [PATCH v7 5/5] iio: magnetometer: ak8975: Add gpio reset support Jonathan Albrieux
@ 2020-05-31 11:02 ` Jonathan Cameron
2020-05-31 16:07 ` Jonathan Albrieux
0 siblings, 1 reply; 3+ messages in thread
From: Jonathan Cameron @ 2020-05-31 11:02 UTC (permalink / raw)
To: Jonathan Albrieux
Cc: linux-kernel, ~postmarketos/upstreaming, Hartmut Knaack,
Lars-Peter Clausen, Peter Meerwald-Stadler, Andy Shevchenko,
Linus Walleij, open list:IIO SUBSYSTEM AND DRIVERS
On Thu, 28 May 2020 17:01:05 +0200
Jonathan Albrieux <jonathan.albrieux@gmail.com> wrote:
> According to AK09911 datasheet, if reset gpio is provided then
> deassert reset on ak8975_power_on() and assert reset on ak8975_power_off().
>
> Without reset's deassertion during ak8975_power_on(), driver's probe fails
> on ak8975_who_i_am() while checking for device identity for AK09911 chip.
>
> AK09911 has an active low reset gpio to handle register's reset.
> AK09911 datasheet says that, if not used, reset pin should be connected
> to VID. This patch emulates this situation.
>
> Signed-off-by: Jonathan Albrieux <jonathan.albrieux@gmail.com>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Reviewed-by: Stephan Gerhold <stephan@gerhold.net>
Applied. Thanks,
Jonathan
> ---
> drivers/iio/magnetometer/ak8975.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
> index fd368455cd7b..a23422aad97d 100644
> --- a/drivers/iio/magnetometer/ak8975.c
> +++ b/drivers/iio/magnetometer/ak8975.c
> @@ -358,6 +358,7 @@ struct ak8975_data {
> u8 asa[3];
> long raw_to_gauss[3];
> struct gpio_desc *eoc_gpiod;
> + struct gpio_desc *reset_gpiod;
> int eoc_irq;
> wait_queue_head_t data_ready_queue;
> unsigned long flags;
> @@ -384,6 +385,9 @@ static int ak8975_power_on(const struct ak8975_data *data)
> "Failed to enable specified Vid supply\n");
> return ret;
> }
> +
> + gpiod_set_value_cansleep(data->reset_gpiod, 0);
> +
> /*
> * According to the datasheet the power supply rise time is 200us
> * and the minimum wait time before mode setting is 100us, in
> @@ -396,6 +400,8 @@ static int ak8975_power_on(const struct ak8975_data *data)
> /* Disable attached power regulator if any. */
> static void ak8975_power_off(const struct ak8975_data *data)
> {
> + gpiod_set_value_cansleep(data->reset_gpiod, 1);
> +
> regulator_disable(data->vid);
> regulator_disable(data->vdd);
> }
> @@ -839,6 +845,7 @@ static int ak8975_probe(struct i2c_client *client,
> struct ak8975_data *data;
> struct iio_dev *indio_dev;
> struct gpio_desc *eoc_gpiod;
> + struct gpio_desc *reset_gpiod;
> const void *match;
> unsigned int i;
> int err;
> @@ -856,6 +863,16 @@ static int ak8975_probe(struct i2c_client *client,
> if (eoc_gpiod)
> gpiod_set_consumer_name(eoc_gpiod, "ak_8975");
>
> + /*
> + * According to AK09911 datasheet, if reset GPIO is provided then
> + * deassert reset on ak8975_power_on() and assert reset on
> + * ak8975_power_off().
> + */
> + reset_gpiod = devm_gpiod_get_optional(&client->dev,
> + "reset", GPIOD_OUT_HIGH);
> + if (IS_ERR(reset_gpiod))
> + return PTR_ERR(reset_gpiod);
> +
> /* Register with IIO */
> indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> if (indio_dev == NULL)
> @@ -866,6 +883,7 @@ static int ak8975_probe(struct i2c_client *client,
>
> data->client = client;
> data->eoc_gpiod = eoc_gpiod;
> + data->reset_gpiod = reset_gpiod;
> data->eoc_irq = 0;
>
> err = iio_read_mount_matrix(&client->dev, "mount-matrix", &data->orientation);
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v7 5/5] iio: magnetometer: ak8975: Add gpio reset support
2020-05-31 11:02 ` Jonathan Cameron
@ 2020-05-31 16:07 ` Jonathan Albrieux
0 siblings, 0 replies; 3+ messages in thread
From: Jonathan Albrieux @ 2020-05-31 16:07 UTC (permalink / raw)
To: Jonathan Cameron
Cc: linux-kernel, ~postmarketos/upstreaming, Hartmut Knaack,
Lars-Peter Clausen, Peter Meerwald-Stadler, Andy Shevchenko,
Linus Walleij, open list:IIO SUBSYSTEM AND DRIVERS
On Sun, May 31, 2020 at 12:02:30PM +0100, Jonathan Cameron wrote:
> On Thu, 28 May 2020 17:01:05 +0200
> Jonathan Albrieux <jonathan.albrieux@gmail.com> wrote:
>
> > According to AK09911 datasheet, if reset gpio is provided then
> > deassert reset on ak8975_power_on() and assert reset on ak8975_power_off().
> >
> > Without reset's deassertion during ak8975_power_on(), driver's probe fails
> > on ak8975_who_i_am() while checking for device identity for AK09911 chip.
> >
> > AK09911 has an active low reset gpio to handle register's reset.
> > AK09911 datasheet says that, if not used, reset pin should be connected
> > to VID. This patch emulates this situation.
> >
> > Signed-off-by: Jonathan Albrieux <jonathan.albrieux@gmail.com>
> > Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > Reviewed-by: Stephan Gerhold <stephan@gerhold.net>
>
> Applied. Thanks,
>
> Jonathan
>
Thank you!
Best regards,
Jonathan Albrieux
> > ---
> > drivers/iio/magnetometer/ak8975.c | 18 ++++++++++++++++++
> > 1 file changed, 18 insertions(+)
> >
> > diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
> > index fd368455cd7b..a23422aad97d 100644
> > --- a/drivers/iio/magnetometer/ak8975.c
> > +++ b/drivers/iio/magnetometer/ak8975.c
> > @@ -358,6 +358,7 @@ struct ak8975_data {
> > u8 asa[3];
> > long raw_to_gauss[3];
> > struct gpio_desc *eoc_gpiod;
> > + struct gpio_desc *reset_gpiod;
> > int eoc_irq;
> > wait_queue_head_t data_ready_queue;
> > unsigned long flags;
> > @@ -384,6 +385,9 @@ static int ak8975_power_on(const struct ak8975_data *data)
> > "Failed to enable specified Vid supply\n");
> > return ret;
> > }
> > +
> > + gpiod_set_value_cansleep(data->reset_gpiod, 0);
> > +
> > /*
> > * According to the datasheet the power supply rise time is 200us
> > * and the minimum wait time before mode setting is 100us, in
> > @@ -396,6 +400,8 @@ static int ak8975_power_on(const struct ak8975_data *data)
> > /* Disable attached power regulator if any. */
> > static void ak8975_power_off(const struct ak8975_data *data)
> > {
> > + gpiod_set_value_cansleep(data->reset_gpiod, 1);
> > +
> > regulator_disable(data->vid);
> > regulator_disable(data->vdd);
> > }
> > @@ -839,6 +845,7 @@ static int ak8975_probe(struct i2c_client *client,
> > struct ak8975_data *data;
> > struct iio_dev *indio_dev;
> > struct gpio_desc *eoc_gpiod;
> > + struct gpio_desc *reset_gpiod;
> > const void *match;
> > unsigned int i;
> > int err;
> > @@ -856,6 +863,16 @@ static int ak8975_probe(struct i2c_client *client,
> > if (eoc_gpiod)
> > gpiod_set_consumer_name(eoc_gpiod, "ak_8975");
> >
> > + /*
> > + * According to AK09911 datasheet, if reset GPIO is provided then
> > + * deassert reset on ak8975_power_on() and assert reset on
> > + * ak8975_power_off().
> > + */
> > + reset_gpiod = devm_gpiod_get_optional(&client->dev,
> > + "reset", GPIOD_OUT_HIGH);
> > + if (IS_ERR(reset_gpiod))
> > + return PTR_ERR(reset_gpiod);
> > +
> > /* Register with IIO */
> > indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> > if (indio_dev == NULL)
> > @@ -866,6 +883,7 @@ static int ak8975_probe(struct i2c_client *client,
> >
> > data->client = client;
> > data->eoc_gpiod = eoc_gpiod;
> > + data->reset_gpiod = reset_gpiod;
> > data->eoc_irq = 0;
> >
> > err = iio_read_mount_matrix(&client->dev, "mount-matrix", &data->orientation);
>
^ permalink raw reply [flat|nested] 3+ messages in thread
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2020-05-28 15:01 [PATCH v7 5/5] iio: magnetometer: ak8975: Add gpio reset support Jonathan Albrieux
2020-05-31 11:02 ` Jonathan Cameron
2020-05-31 16:07 ` Jonathan Albrieux
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