Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754497AbcDJNQZ (ORCPT ); Sun, 10 Apr 2016 09:16:25 -0400 Received: from saturn.retrosnub.co.uk ([178.18.118.26]:43770 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753714AbcDJNQW (ORCPT ); Sun, 10 Apr 2016 09:16:22 -0400 Subject: Re: [PATCH 3/5] max44000: Support controlling LED current output To: Crestez Dan Leonard , linux-iio@vger.kernel.org References: <1f9ec5350bd3349236887ed89378c319eddc005f.1460045763.git.leonard.crestez@intel.com> Cc: linux-kernel@vger.kernel.org, Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Daniel Baluta From: Jonathan Cameron Message-ID: <570A5219.9040802@kernel.org> Date: Sun, 10 Apr 2016 14:16:09 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.7.1 MIME-Version: 1.0 In-Reply-To: <1f9ec5350bd3349236887ed89378c319eddc005f.1460045763.git.leonard.crestez@intel.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3411 Lines: 111 On 07/04/16 17:21, Crestez Dan Leonard wrote: > This is exposed as an output channel with "led" as an extend_name. > > Other sensors also have support for controlling an external LED. It's > not clear that simply exposing an undecorated output channel is the > correct approach. Agreed that this is less than ideal. Other suggestions welcome. It gets complicated as some devices have multiple LEDs and they aren't necessarily directly associated with a particular sensor. > > Signed-off-by: Crestez Dan Leonard > --- > drivers/iio/light/max44000.c | 53 ++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 53 insertions(+) > > diff --git a/drivers/iio/light/max44000.c b/drivers/iio/light/max44000.c > index 10a0fe8..1dc10b9 100644 > --- a/drivers/iio/light/max44000.c > +++ b/drivers/iio/light/max44000.c > @@ -85,6 +85,13 @@ static const struct iio_chan_spec max44000_channels[] = { > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), > .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), > }, > + { > + .type = IIO_CURRENT, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | > + BIT(IIO_CHAN_INFO_SCALE), > + .extend_name = "led", > + .output = 1, > + }, > }; > > static inline int max44000_read_alsval(struct max44000_data *data) > @@ -124,6 +131,20 @@ static inline int max44000_write_led_current_raw(struct max44000_data *data, int > MAX44000_LED_CURRENT_MASK, val); > } > > +static inline int max44000_read_led_current_raw(struct max44000_data *data) > +{ > + unsigned int regval; > + int ret; > + > + ret = regmap_read(data->regmap, MAX44000_REG_CFG_TX, ®val); > + if (ret < 0) > + return ret; > + regval &= MAX44000_LED_CURRENT_MASK; > + if (regval >= 8) > + regval -= 4; > + return regval; > +} > + > static int max44000_read_raw(struct iio_dev *indio_dev, > struct iio_chan_spec const *chan, > int *val, int *val2, long mask) > @@ -153,12 +174,26 @@ static int max44000_read_raw(struct iio_dev *indio_dev, > *val = regval; > return IIO_VAL_INT; > > + case IIO_CURRENT: > + mutex_lock(&data->lock); > + ret = max44000_read_led_current_raw(data); > + mutex_unlock(&data->lock); > + if (ret < 0) > + return ret; > + *val = ret; > + return IIO_VAL_INT; > + > default: > return -EINVAL; > } > > case IIO_CHAN_INFO_SCALE: > switch (chan->type) { > + case IIO_CURRENT: > + /* Output register is in 10s of miliamps */ > + *val = 10; > + return IIO_VAL_INT; > + > case IIO_LIGHT: > *val = 1; > *val2 = MAX44000_ALS_TO_LUX_DEFAULT_FRACTION_LOG2; > @@ -173,9 +208,27 @@ static int max44000_read_raw(struct iio_dev *indio_dev, > } > } > > +static int max44000_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int val, int val2, long mask) > +{ > + struct max44000_data *data = iio_priv(indio_dev); > + int ret; > + > + if (mask == IIO_CHAN_INFO_RAW && chan->type == IIO_CURRENT) { > + mutex_lock(&data->lock); > + ret = max44000_write_led_current_raw(data, val); > + mutex_unlock(&data->lock); > + return ret; > + } > + > + return -EINVAL; > +} > + > static const struct iio_info max44000_info = { > .driver_module = THIS_MODULE, > .read_raw = max44000_read_raw, > + .write_raw = max44000_write_raw, > }; > > static bool max44000_readable_reg(struct device *dev, unsigned int reg) >