From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com ([134.134.136.65]:51662 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751080AbbKJM0j (ORCPT ); Tue, 10 Nov 2015 07:26:39 -0500 Subject: Re: [PATCH v4 1/1] iio: pulsedlight-lidar-lite: add runtime PM To: Matt Ranostay , jic23@kernel.org References: <1447014418-27849-1-git-send-email-mranostay@gmail.com> <1447014418-27849-2-git-send-email-mranostay@gmail.com> Cc: linux-iio@vger.kernel.org, linux-pm@vger.kernel.org, k.kozlowski@samsung.com From: Adriana Reus Message-ID: <5641E267.6010204@intel.com> Date: Tue, 10 Nov 2015 14:26:15 +0200 MIME-Version: 1.0 In-Reply-To: <1447014418-27849-2-git-send-email-mranostay@gmail.com> Content-Type: text/plain; charset=windows-1252; format=flowed Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 08.11.2015 22:26, Matt Ranostay wrote: > Add runtime PM support for the lidar-lite module to enable low power > mode when last device requested reading is over a second. > > Signed-off-by: Matt Ranostay > --- > drivers/iio/proximity/pulsedlight-lidar-lite-v2.c | 54 ++++++++++++++++++++++- > 1 file changed, 53 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c b/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c > index 961f9f99..1a5481f 100644 > --- a/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c > +++ b/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c > @@ -13,7 +13,7 @@ > * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > * GNU General Public License for more details. > * > - * TODO: runtime pm, interrupt mode, and signal strength reporting > + * TODO: interrupt mode, and signal strength reporting > */ > > #include > @@ -21,6 +21,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -37,6 +38,7 @@ > > #define LIDAR_REG_DATA_HBYTE 0x0f > #define LIDAR_REG_DATA_LBYTE 0x10 > +#define LIDAR_REG_PWR_CONTROL 0x65 > > #define LIDAR_DRV_NAME "lidar" > > @@ -90,6 +92,12 @@ static inline int lidar_write_control(struct lidar_data *data, int val) > return i2c_smbus_write_byte_data(data->client, LIDAR_REG_CONTROL, val); > } > > +static inline int lidar_write_power(struct lidar_data *data, int val) > +{ > + return i2c_smbus_write_byte_data(data->client, > + LIDAR_REG_PWR_CONTROL, val); > +} > + > static int lidar_read_measurement(struct lidar_data *data, u16 *reg) > { > int ret; > @@ -116,6 +124,8 @@ static int lidar_get_measurement(struct lidar_data *data, u16 *reg) > int tries = 10; > int ret; > > + pm_runtime_get_sync(&client->dev); > + > /* start sample */ > ret = lidar_write_control(data, LIDAR_REG_CONTROL_ACQUIRE); > if (ret < 0) { > @@ -144,6 +154,8 @@ static int lidar_get_measurement(struct lidar_data *data, u16 *reg) > } > ret = -EIO; > } > + pm_runtime_mark_last_busy(&client->dev); > + pm_runtime_put_autosuspend(&client->dev); > > return ret; > } > @@ -243,6 +255,15 @@ static int lidar_probe(struct i2c_client *client, > if (ret) > goto error_unreg_buffer; > > + pm_runtime_set_autosuspend_delay(&client->dev, 1000); > + pm_runtime_use_autosuspend(&client->dev); > + > + pm_runtime_set_active(&client->dev); pm_runtime_set_active ^ may return an error code. > + pm_runtime_enable(&client->dev); > + > + pm_runtime_mark_last_busy(&client->dev); > + pm_runtime_idle(&client->dev); > + > return 0; > > error_unreg_buffer: > @@ -258,6 +279,9 @@ static int lidar_remove(struct i2c_client *client) > iio_device_unregister(indio_dev); > iio_triggered_buffer_cleanup(indio_dev); > > + pm_runtime_disable(&client->dev); > + pm_runtime_set_suspended(&client->dev); > + > return 0; > } > > @@ -273,10 +297,38 @@ static const struct of_device_id lidar_dt_ids[] = { > }; > MODULE_DEVICE_TABLE(of, lidar_dt_ids); > > +#ifdef CONFIG_PM > +static int lidar_pm_runtime_suspend(struct device *dev) > +{ > + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); > + struct lidar_data *data = iio_priv(indio_dev); > + > + return lidar_write_power(data, 0x0f); > +} > + > +static int lidar_pm_runtime_resume(struct device *dev) > +{ > + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); > + struct lidar_data *data = iio_priv(indio_dev); > + int ret = lidar_write_power(data, 0); > + > + /* regulator and FPGA needs settling time */ > + usleep_range(15000, 20000); > + > + return ret; > +} > +#endif > + > +static const struct dev_pm_ops lidar_pm_ops = { > + SET_RUNTIME_PM_OPS(lidar_pm_runtime_suspend, > + lidar_pm_runtime_resume, NULL) > +}; > + > static struct i2c_driver lidar_driver = { > .driver = { > .name = LIDAR_DRV_NAME, > .of_match_table = of_match_ptr(lidar_dt_ids), > + .pm = &lidar_pm_ops, > }, > .probe = lidar_probe, > .remove = lidar_remove, >