From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752307AbcFKPse (ORCPT ); Sat, 11 Jun 2016 11:48:34 -0400 Received: from saturn.retrosnub.co.uk ([178.18.118.26]:51996 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751301AbcFKPsc (ORCPT ); Sat, 11 Jun 2016 11:48:32 -0400 Subject: Re: [PATCH v2 2/4] iio: adc: mxs-lradc: Add support for adc driver To: Ksenija Stanojevic , linux-kernel@vger.kernel.org References: Cc: lee.jones@linaro.org, dmitry.torokhov@gmail.com, linux-input@vger.kernel.org, knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, marex@denx.de, linux-iio@vger.kernel.org, harald@ccbib.org, stefan.wahren@i2se.com, fabio.estevam@freescale.com From: Jonathan Cameron Message-ID: Date: Sat, 11 Jun 2016 16:48:27 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0 MIME-Version: 1.0 In-Reply-To: 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 On 08/06/16 15:47, Ksenija Stanojevic wrote: > Add support for sixteen-channel 12-bit resolution ADC and its functions, > which include general-purpose ADC readings, battery voltage measurement, > and die temperature measurement. > > Signed-off-by: Ksenija Stanojevic Some really trivial white space comments inline... + I think you need to add 2 to the number of elements in your buffer array. Fix that and you can add Acked-by: Jonathan Cameron > --- > Changes in v2: > - improve commit message > - do not change spacing in Kconfig > - impove formating > - remove wrapper show_scale_avail > - use correct syntax for comments > - use devm_iio_trigger_alloc > - do not allocate buffer dynamically > - use iio_device_claim_*_mode helpers > - add spinlock in struct mxs_lradc_ts to enable locking in interrupt handler > - only grab irqs that are relevant to adc > - remove blank line at the end of the file > - change licence to GPL > - add copyright > > drivers/iio/adc/Kconfig | 13 + > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/mxs-lradc-adc.c | 813 ++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 827 insertions(+) > create mode 100644 drivers/iio/adc/mxs-lradc-adc.c > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 932de1f..4ef3ad1 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -194,6 +194,19 @@ config EXYNOS_ADC > To compile this driver as a module, choose M here: the module will be > called exynos_adc. > > +config MXS_LRADC_ADC > + tristate "Freescale i.MX23/i.MX28 LRADC ADC" > + depends on MFD_MXS_LRADC > + select IIO_BUFFER > + select IIO_TRIGGERED_BUFFER > + help > + Say yes here to build support for the ADC functions of the > + i.MX23/i.MX28 LRADC. This includes general-purpose ADC readings, > + battery voltage measurement, and die temperature measurement. > + > + This driver can also be built as a module. If so, the module will be > + called mxs-lradc-adc. > + > config HI8435 > tristate "Holt Integrated Circuits HI-8435 threshold detector" > select IIO_TRIGGERED_EVENT > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index b1aa456..9bb35c4 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -29,6 +29,7 @@ obj-$(CONFIG_MAX1363) += max1363.o > obj-$(CONFIG_MCP320X) += mcp320x.o > obj-$(CONFIG_MCP3422) += mcp3422.o > obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o > +obj-$(CONFIG_MXS_LRADC_ADC) += mxs-lradc-adc.o > obj-$(CONFIG_MXS_LRADC) += mxs-lradc.o > obj-$(CONFIG_NAU7802) += nau7802.o > obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o > diff --git a/drivers/iio/adc/mxs-lradc-adc.c b/drivers/iio/adc/mxs-lradc-adc.c > new file mode 100644 > index 0000000..3b00bc0 > --- /dev/null > +++ b/drivers/iio/adc/mxs-lradc-adc.c > @@ -0,0 +1,813 @@ > +/* > + * Freescale MXS LRADC ADC driver > + * > + * Copyright (c) 2012 DENX Software Engineering, GmbH. > + * Marek Vasut > + * Ksenija Stanojevic > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* > + * Make this runtime configurable if necessary. Currently, if the buffered mode > + * is enabled, the LRADC takes LRADC_DELAY_TIMER_LOOP samples of data before > + * triggering IRQ. The sampling happens every (LRADC_DELAY_TIMER_PER / 2000) > + * seconds. The result is that the samples arrive every 500mS. > + */ > +#define LRADC_DELAY_TIMER_PER 200 > +#define LRADC_DELAY_TIMER_LOOP 5 > + > +#define VREF_MV_BASE 1850 > + > +#define IMX23_NUM_IRQ 6 > +#define IMX28_NUM_IRQ 10 > + > +static const int mx23_lradc_adc_irq[] = {1, 2, 3, 4, 5, 6}; > +static const int mx28_lradc_adc_irq[] = {1, 2, 3, 4, 5, 6, 7, 8, 11, 12}; > + > +static const u32 mxs_lradc_adc_vref_mv[][LRADC_MAX_TOTAL_CHANS] = { > + [IMX23_LRADC] = { > + VREF_MV_BASE, /* CH0 */ > + VREF_MV_BASE, /* CH1 */ > + VREF_MV_BASE, /* CH2 */ > + VREF_MV_BASE, /* CH3 */ > + VREF_MV_BASE, /* CH4 */ > + VREF_MV_BASE, /* CH5 */ > + VREF_MV_BASE * 2, /* CH6 VDDIO */ > + VREF_MV_BASE * 4, /* CH7 VBATT */ > + VREF_MV_BASE, /* CH8 Temp sense 0 */ > + VREF_MV_BASE, /* CH9 Temp sense 1 */ > + VREF_MV_BASE, /* CH10 */ > + VREF_MV_BASE, /* CH11 */ > + VREF_MV_BASE, /* CH12 USB_DP */ > + VREF_MV_BASE, /* CH13 USB_DN */ > + VREF_MV_BASE, /* CH14 VBG */ > + VREF_MV_BASE * 4, /* CH15 VDD5V */ > + }, > + [IMX28_LRADC] = { > + VREF_MV_BASE, /* CH0 */ > + VREF_MV_BASE, /* CH1 */ > + VREF_MV_BASE, /* CH2 */ > + VREF_MV_BASE, /* CH3 */ > + VREF_MV_BASE, /* CH4 */ > + VREF_MV_BASE, /* CH5 */ > + VREF_MV_BASE, /* CH6 */ > + VREF_MV_BASE * 4, /* CH7 VBATT */ > + VREF_MV_BASE, /* CH8 Temp sense 0 */ > + VREF_MV_BASE, /* CH9 Temp sense 1 */ > + VREF_MV_BASE * 2, /* CH10 VDDIO */ > + VREF_MV_BASE, /* CH11 VTH */ > + VREF_MV_BASE * 2, /* CH12 VDDA */ > + VREF_MV_BASE, /* CH13 VDDD */ > + VREF_MV_BASE, /* CH14 VBG */ > + VREF_MV_BASE * 4, /* CH15 VDD5V */ > + }, > +}; > + > +enum mxs_lradc_divbytwo { > + MXS_LRADC_DIV_DISABLED = 0, > + MXS_LRADC_DIV_ENABLED, > +}; > + > +struct mxs_lradc_scale { > + unsigned int integer; > + unsigned int nano; > +}; > + > +struct mxs_lradc_adc { > + struct mxs_lradc *lradc; > + struct device *dev; > + > + u32 buffer[8]; Is this big enough? Check the docs for iio_push_to_buffers_with_timestamp (need space for the timestamp as well as the channels). So I think it should be buffer[10]; > + struct iio_trigger *trig; > + struct completion completion; > + spinlock_t lock; > + > + const u32 *vref_mv; > + struct mxs_lradc_scale scale_avail[LRADC_MAX_TOTAL_CHANS][2]; > + unsigned long is_divided; > +}; > + > + > +/* Raw I/O operations */ > +static int mxs_lradc_adc_read_single(struct iio_dev *iio_dev, int chan, > + int *val) > +{ > + struct mxs_lradc_adc *adc = iio_priv(iio_dev); > + struct mxs_lradc *lradc = adc->lradc; > + int ret; > + > + /* > + * See if there is no buffered operation in progress. If there is simply > + * bail out. This can be improved to support both buffered and raw IO at > + * the same time, yet the code becomes horribly complicated. Therefore I > + * applied KISS principle here. > + */ > + ret = iio_device_claim_direct_mode(iio_dev); > + if (ret) > + return ret; > + > + reinit_completion(&adc->completion); > + > + /* > + * No buffered operation in progress, map the channel and trigger it. > + * Virtual channel 0 is always used here as the others are always not > + * used if doing raw sampling. > + */ > + if (lradc->soc == IMX28_LRADC) > + mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), > + LRADC_CTRL1); > + mxs_lradc_reg_clear(lradc, 0x1, LRADC_CTRL0); > + > + /* Enable / disable the divider per requirement */ > + if (test_bit(chan, &adc->is_divided)) > + mxs_lradc_reg_set(lradc, > + 1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET, > + LRADC_CTRL2); > + else > + mxs_lradc_reg_clear(lradc, > + 1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET, > + LRADC_CTRL2); > + > + /* Clean the slot's previous content, then set new one. */ > + mxs_lradc_reg_clear(lradc, LRADC_CTRL4_LRADCSELECT_MASK(0), > + LRADC_CTRL4); > + mxs_lradc_reg_set(lradc, chan, LRADC_CTRL4); > + > + mxs_lradc_reg_wrt(lradc, 0, LRADC_CH(0)); > + > + /* Enable the IRQ and start sampling the channel. */ > + mxs_lradc_reg_set(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1); > + mxs_lradc_reg_set(lradc, BIT(0), LRADC_CTRL0); > + > + /* Wait for completion on the channel, 1 second max. */ > + ret = wait_for_completion_killable_timeout(&adc->completion, HZ); > + if (!ret) > + ret = -ETIMEDOUT; > + if (ret < 0) > + goto err; > + > + /* Read the data. */ > + *val = readl(lradc->base + LRADC_CH(0)) & LRADC_CH_VALUE_MASK; > + ret = IIO_VAL_INT; > + > +err: > + mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1); > + > + iio_device_release_direct_mode(iio_dev); > + > + return ret; > +} > + > +static int mxs_lradc_adc_read_temp(struct iio_dev *iio_dev, int *val) > +{ > + int ret, min, max; > + > + ret = mxs_lradc_adc_read_single(iio_dev, 8, &min); > + if (ret != IIO_VAL_INT) > + return ret; > + > + ret = mxs_lradc_adc_read_single(iio_dev, 9, &max); > + if (ret != IIO_VAL_INT) > + return ret; > + > + *val = max - min; > + > + return IIO_VAL_INT; > +} > + > +static int mxs_lradc_adc_read_raw(struct iio_dev *iio_dev, > + const struct iio_chan_spec *chan, > + int *val, int *val2, long m) > +{ > + struct mxs_lradc_adc *adc = iio_priv(iio_dev); > + > + switch (m) { > + case IIO_CHAN_INFO_RAW: > + if (chan->type == IIO_TEMP) > + return mxs_lradc_adc_read_temp(iio_dev, val); > + > + return mxs_lradc_adc_read_single(iio_dev, chan->channel, val); > + > + case IIO_CHAN_INFO_SCALE: > + if (chan->type == IIO_TEMP) { > + /* > + * From the datasheet, we have to multiply by 1.012 and > + * divide by 4 > + */ > + *val = 0; > + *val2 = 253000; > + return IIO_VAL_INT_PLUS_MICRO; > + } > + > + *val = adc->vref_mv[chan->channel]; > + *val2 = chan->scan_type.realbits - > + test_bit(chan->channel, &adc->is_divided); > + return IIO_VAL_FRACTIONAL_LOG2; > + > + case IIO_CHAN_INFO_OFFSET: > + if (chan->type == IIO_TEMP) { > + /* > + * The calculated value from the ADC is in Kelvin, we > + * want Celsius for hwmon so the offset is -273.15 > + * The offset is applied before scaling so it is > + * actually -213.15 * 4 / 1.012 = -1079.644268 > + */ > + *val = -1079; > + *val2 = 644268; > + > + return IIO_VAL_INT_PLUS_MICRO; > + } > + > + return -EINVAL; > + > + default: > + break; > + } > + > + return -EINVAL; > +} > + > +static int mxs_lradc_adc_write_raw(struct iio_dev *iio_dev, > + const struct iio_chan_spec *chan, > + int val, int val2, long m) > +{ > + struct mxs_lradc_adc *adc = iio_priv(iio_dev); > + struct mxs_lradc_scale *scale_avail = > + adc->scale_avail[chan->channel]; > + int ret; > + > + ret = iio_device_claim_direct_mode(iio_dev); > + if (ret) > + return ret; > + > + switch (m) { > + case IIO_CHAN_INFO_SCALE: > + ret = -EINVAL; > + if (val == scale_avail[MXS_LRADC_DIV_DISABLED].integer && > + val2 == scale_avail[MXS_LRADC_DIV_DISABLED].nano) { > + /* divider by two disabled */ > + clear_bit(chan->channel, &adc->is_divided); > + ret = 0; > + } else if (val == scale_avail[MXS_LRADC_DIV_ENABLED].integer && > + val2 == scale_avail[MXS_LRADC_DIV_ENABLED].nano) { > + /* divider by two enabled */ > + set_bit(chan->channel, &adc->is_divided); > + ret = 0; > + } > + > + break; > + default: > + ret = -EINVAL; > + break; > + } > + > + iio_device_release_direct_mode(iio_dev); > + > + return ret; > +} > + > +static int mxs_lradc_adc_write_raw_get_fmt(struct iio_dev *iio_dev, > + const struct iio_chan_spec *chan, > + long m) > +{ > + return IIO_VAL_INT_PLUS_NANO; > +} > + > +static ssize_t mxs_lradc_adc_show_scale_avail(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct iio_dev *iio = dev_to_iio_dev(dev); > + struct mxs_lradc_adc *adc = iio_priv(iio); > + struct iio_dev_attr *iio_attr = to_iio_dev_attr(attr); > + int i, ch, len = 0; > + > + ch = iio_attr->address; > + for (i = 0; i < ARRAY_SIZE(adc->scale_avail[ch]); i++) > + len += sprintf(buf + len, "%u.%09u ", > + adc->scale_avail[ch][i].integer, > + adc->scale_avail[ch][i].nano); > + > + len += sprintf(buf + len, "\n"); > + > + return len; > +} > + > +#define SHOW_SCALE_AVAILABLE_ATTR(ch) \ > +static IIO_DEVICE_ATTR(in_voltage##ch##_scale_available, S_IRUGO, \ > + mxs_lradc_adc_show_scale_avail, NULL, ch) > + > +SHOW_SCALE_AVAILABLE_ATTR(0); > +SHOW_SCALE_AVAILABLE_ATTR(1); > +SHOW_SCALE_AVAILABLE_ATTR(2); > +SHOW_SCALE_AVAILABLE_ATTR(3); > +SHOW_SCALE_AVAILABLE_ATTR(4); > +SHOW_SCALE_AVAILABLE_ATTR(5); > +SHOW_SCALE_AVAILABLE_ATTR(6); > +SHOW_SCALE_AVAILABLE_ATTR(7); > +SHOW_SCALE_AVAILABLE_ATTR(10); > +SHOW_SCALE_AVAILABLE_ATTR(11); > +SHOW_SCALE_AVAILABLE_ATTR(12); > +SHOW_SCALE_AVAILABLE_ATTR(13); > +SHOW_SCALE_AVAILABLE_ATTR(14); > +SHOW_SCALE_AVAILABLE_ATTR(15); > + > +static struct attribute *mxs_lradc_adc_attributes[] = { > + &iio_dev_attr_in_voltage0_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage1_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage2_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage3_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage4_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage5_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage6_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage7_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage10_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage11_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage12_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage13_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage14_scale_available.dev_attr.attr, > + &iio_dev_attr_in_voltage15_scale_available.dev_attr.attr, > + NULL > +}; > + > +static const struct attribute_group mxs_lradc_adc_attribute_group = { > + .attrs = mxs_lradc_adc_attributes, > +}; > + > +static const struct iio_info mxs_lradc_adc_iio_info = { > + .driver_module = THIS_MODULE, > + .read_raw = mxs_lradc_adc_read_raw, > + .write_raw = mxs_lradc_adc_write_raw, > + .write_raw_get_fmt = mxs_lradc_adc_write_raw_get_fmt, > + .attrs = &mxs_lradc_adc_attribute_group, > +}; > + > + one blank line only preferered. > +/* IRQ Handling */ > +static irqreturn_t mxs_lradc_adc_handle_irq(int irq, void *data) > +{ > + struct iio_dev *iio = data; > + struct mxs_lradc_adc *adc = iio_priv(iio); > + struct mxs_lradc *lradc = adc->lradc; > + unsigned long reg = readl(lradc->base + LRADC_CTRL1); > + unsigned long flags; > + > + if (!(reg & mxs_lradc_irq_mask(lradc))) > + return IRQ_NONE; > + > + if (iio_buffer_enabled(iio)) { > + if (reg & lradc->buffer_vchans) { > + spin_lock_irqsave(&adc->lock, flags); > + iio_trigger_poll(iio->trig); > + spin_unlock_irqrestore(&adc->lock, flags); > + } > + } else if (reg & LRADC_CTRL1_LRADC_IRQ(0)) { > + complete(&adc->completion); > + } > + > + mxs_lradc_reg_clear(lradc, reg & mxs_lradc_irq_mask(lradc), > + LRADC_CTRL1); > + > + return IRQ_HANDLED; > +} > + > + > +/* Trigger handling */ > +static irqreturn_t mxs_lradc_adc_trigger_handler(int irq, void *p) > +{ > + struct iio_poll_func *pf = p; > + struct iio_dev *iio = pf->indio_dev; > + struct mxs_lradc_adc *adc = iio_priv(iio); > + const u32 chan_value = LRADC_CH_ACCUMULATE | > + ((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET); > + unsigned int i, j = 0; > + > + for_each_set_bit(i, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) { > + adc->buffer[j] = readl(adc->lradc->base + LRADC_CH(j)); > + mxs_lradc_reg_wrt(adc->lradc, chan_value, LRADC_CH(j)); > + adc->buffer[j] &= LRADC_CH_VALUE_MASK; > + adc->buffer[j] /= LRADC_DELAY_TIMER_LOOP; > + j++; > + } > + > + iio_push_to_buffers_with_timestamp(iio, adc->buffer, pf->timestamp); > + > + iio_trigger_notify_done(iio->trig); > + > + return IRQ_HANDLED; > +} > + > +static int mxs_lradc_adc_configure_trigger(struct iio_trigger *trig, bool state) > +{ > + struct iio_dev *iio = iio_trigger_get_drvdata(trig); > + struct mxs_lradc_adc *adc = iio_priv(iio); > + const u32 st = state ? STMP_OFFSET_REG_SET : STMP_OFFSET_REG_CLR; > + > + mxs_lradc_reg_wrt(adc->lradc, LRADC_DELAY_KICK, LRADC_DELAY(0) + st); > + > + return 0; > +} > + > +static const struct iio_trigger_ops mxs_lradc_adc_trigger_ops = { > + .owner = THIS_MODULE, > + .set_trigger_state = &mxs_lradc_adc_configure_trigger, > +}; > + > +static int mxs_lradc_adc_trigger_init(struct iio_dev *iio) > +{ > + int ret; > + struct iio_trigger *trig; > + struct mxs_lradc_adc *adc = iio_priv(iio); > + > + trig = devm_iio_trigger_alloc(&iio->dev, "%s-dev%i", iio->name, > + iio->id); > + > + trig->dev.parent = adc->dev; > + iio_trigger_set_drvdata(trig, iio); > + trig->ops = &mxs_lradc_adc_trigger_ops; > + > + ret = iio_trigger_register(trig); > + if (ret) > + return ret; > + > + adc->trig = trig; > + > + return 0; > +} > + > +static void mxs_lradc_adc_trigger_remove(struct iio_dev *iio) > +{ > + struct mxs_lradc_adc *adc = iio_priv(iio); > + > + iio_trigger_unregister(adc->trig); > +} > + > +static int mxs_lradc_adc_buffer_preenable(struct iio_dev *iio) > +{ > + struct mxs_lradc_adc *adc = iio_priv(iio); > + struct mxs_lradc *lradc = adc->lradc; > + int chan, ofs = 0; > + unsigned long enable = 0; > + u32 ctrl4_set = 0; > + u32 ctrl4_clr = 0; > + u32 ctrl1_irq = 0; > + const u32 chan_value = LRADC_CH_ACCUMULATE | > + ((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET); > + > + if (lradc->soc == IMX28_LRADC) > + mxs_lradc_reg_clear(lradc, > + lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET, > + LRADC_CTRL1); > + mxs_lradc_reg_clear(lradc, lradc->buffer_vchans, LRADC_CTRL0); > + > + for_each_set_bit(chan, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) { > + ctrl4_set |= chan << LRADC_CTRL4_LRADCSELECT_OFFSET(ofs); > + ctrl4_clr |= LRADC_CTRL4_LRADCSELECT_MASK(ofs); > + ctrl1_irq |= LRADC_CTRL1_LRADC_IRQ_EN(ofs); > + mxs_lradc_reg_wrt(lradc, chan_value, LRADC_CH(ofs)); > + bitmap_set(&enable, ofs, 1); > + ofs++; > + } > + > + mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK | > + LRADC_DELAY_KICK, LRADC_DELAY(0)); > + mxs_lradc_reg_clear(lradc, ctrl4_clr, LRADC_CTRL4); > + mxs_lradc_reg_set(lradc, ctrl4_set, LRADC_CTRL4); > + mxs_lradc_reg_set(lradc, ctrl1_irq, LRADC_CTRL1); > + mxs_lradc_reg_set(lradc, enable << LRADC_DELAY_TRIGGER_LRADCS_OFFSET, > + LRADC_DELAY(0)); > + > + return 0; > +} > + > +static int mxs_lradc_adc_buffer_postdisable(struct iio_dev *iio) > +{ > + struct mxs_lradc_adc *adc = iio_priv(iio); > + struct mxs_lradc *lradc = adc->lradc; > + > + mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK | > + LRADC_DELAY_KICK, LRADC_DELAY(0)); > + > + mxs_lradc_reg_clear(lradc, lradc->buffer_vchans, LRADC_CTRL0); > + if (lradc->soc == IMX28_LRADC) > + mxs_lradc_reg_clear(lradc, > + lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET, > + LRADC_CTRL1); > + > + return 0; > +} > + > +static bool mxs_lradc_adc_validate_scan_mask(struct iio_dev *iio, > + const unsigned long *mask) > +{ > + struct mxs_lradc_adc *adc = iio_priv(iio); > + struct mxs_lradc *lradc = adc->lradc; > + const int map_chans = bitmap_weight(mask, LRADC_MAX_TOTAL_CHANS); > + int rsvd_chans = 0; > + unsigned long rsvd_mask = 0; > + > + if (lradc->use_touchbutton) > + rsvd_mask |= CHAN_MASK_TOUCHBUTTON; > + if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_4WIRE) > + rsvd_mask |= CHAN_MASK_TOUCHSCREEN_4WIRE; > + if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE) > + rsvd_mask |= CHAN_MASK_TOUCHSCREEN_5WIRE; > + > + if (lradc->use_touchbutton) > + rsvd_chans++; > + if (lradc->use_touchscreen) > + rsvd_chans += 2; > + > + /* Test for attempts to map channels with special mode of operation. */ > + if (bitmap_intersects(mask, &rsvd_mask, LRADC_MAX_TOTAL_CHANS)) > + return false; > + > + /* Test for attempts to map more channels then available slots. */ > + if (map_chans + rsvd_chans > LRADC_MAX_MAPPED_CHANS) > + return false; > + > + return true; > +} > + > +static const struct iio_buffer_setup_ops mxs_lradc_adc_buffer_ops = { > + .preenable = &mxs_lradc_adc_buffer_preenable, > + .postenable = &iio_triggered_buffer_postenable, > + .predisable = &iio_triggered_buffer_predisable, > + .postdisable = &mxs_lradc_adc_buffer_postdisable, > + .validate_scan_mask = &mxs_lradc_adc_validate_scan_mask, > +}; > + > +/* Driver initialization */ > +#define MXS_ADC_CHAN(idx, chan_type, name) { \ > + .type = (chan_type), \ > + .indexed = 1, \ > + .scan_index = (idx), \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ > + BIT(IIO_CHAN_INFO_SCALE), \ > + .channel = (idx), \ > + .address = (idx), \ > + .scan_type = { \ > + .sign = 'u', \ > + .realbits = LRADC_RESOLUTION, \ > + .storagebits = 32, \ > + }, \ > + .datasheet_name = (name), \ > +} > + > +static const struct iio_chan_spec mx23_lradc_chan_spec[] = { > + MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"), > + MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"), > + MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"), > + MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"), > + MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"), > + MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"), > + MXS_ADC_CHAN(6, IIO_VOLTAGE, "VDDIO"), > + MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"), > + /* Combined Temperature sensors */ > + { > + .type = IIO_TEMP, > + .indexed = 1, > + .scan_index = 8, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | > + BIT(IIO_CHAN_INFO_OFFSET) | > + BIT(IIO_CHAN_INFO_SCALE), > + .channel = 8, > + .scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,}, > + .datasheet_name = "TEMP_DIE", > + }, > + /* Hidden channel to keep indexes */ > + { > + .type = IIO_TEMP, > + .indexed = 1, > + .scan_index = -1, > + .channel = 9, > + }, > + MXS_ADC_CHAN(10, IIO_VOLTAGE, NULL), > + MXS_ADC_CHAN(11, IIO_VOLTAGE, NULL), > + MXS_ADC_CHAN(12, IIO_VOLTAGE, "USB_DP"), > + MXS_ADC_CHAN(13, IIO_VOLTAGE, "USB_DN"), > + MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"), > + MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"), > +}; > + > +static const struct iio_chan_spec mx28_lradc_chan_spec[] = { > + MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"), > + MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"), > + MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"), > + MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"), > + MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"), > + MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"), > + MXS_ADC_CHAN(6, IIO_VOLTAGE, "LRADC6"), > + MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"), > + /* Combined Temperature sensors */ > + { > + .type = IIO_TEMP, > + .indexed = 1, > + .scan_index = 8, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | > + BIT(IIO_CHAN_INFO_OFFSET) | > + BIT(IIO_CHAN_INFO_SCALE), > + .channel = 8, > + .scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,}, > + .datasheet_name = "TEMP_DIE", > + }, > + /* Hidden channel to keep indexes */ > + { > + .type = IIO_TEMP, > + .indexed = 1, > + .scan_index = -1, > + .channel = 9, > + }, > + MXS_ADC_CHAN(10, IIO_VOLTAGE, "VDDIO"), > + MXS_ADC_CHAN(11, IIO_VOLTAGE, "VTH"), > + MXS_ADC_CHAN(12, IIO_VOLTAGE, "VDDA"), > + MXS_ADC_CHAN(13, IIO_VOLTAGE, "VDDD"), > + MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"), > + MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"), > +}; > + > +static void mxs_lradc_adc_hw_init(struct mxs_lradc_adc *adc) > +{ > + struct mxs_lradc *lradc = adc->lradc; > + > + /* The ADC always uses DELAY CHANNEL 0. */ > + const u32 adc_cfg = > + (1 << (LRADC_DELAY_TRIGGER_DELAYS_OFFSET + 0)) | > + (LRADC_DELAY_TIMER_PER << LRADC_DELAY_DELAY_OFFSET); > + > + /* Configure DELAY CHANNEL 0 for generic ADC sampling. */ > + mxs_lradc_reg_wrt(lradc, adc_cfg, LRADC_DELAY(0)); > + > + /* > + * Start internal temperature sensing by clearing bit > + * HW_LRADC_CTRL2_TEMPSENSE_PWD. This bit can be left cleared > + * after power up. > + */ > + mxs_lradc_reg_wrt(lradc, 0, LRADC_CTRL2); > +} > + > +static void mxs_lradc_adc_hw_stop(struct mxs_lradc_adc *adc) > +{ > + mxs_lradc_reg_wrt(adc->lradc, 0, LRADC_DELAY(0)); > +} > + > +static int mxs_lradc_adc_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct mxs_lradc *lradc = dev_get_platdata(dev); > + struct mxs_lradc_adc *adc; > + struct iio_dev *iio; > + int ret, i, j, s, n; > + u64 scale_uv; > + const int *irq; > + > + One blank line only prefered. > + /* Allocate the IIO device. */ > + iio = devm_iio_device_alloc(dev, sizeof(*adc)); > + if (!iio) { > + dev_err(dev, "Failed to allocate IIO device\n"); > + return -ENOMEM; > + } > + > + adc = iio_priv(iio); > + adc->lradc = lradc; > + adc->dev = dev; > + > + init_completion(&adc->completion); > + spin_lock_init(&adc->lock); > + > + platform_set_drvdata(pdev, iio); > + > + iio->name = pdev->name; > + iio->dev.parent = dev; > + iio->dev.of_node = dev->parent->of_node; > + iio->info = &mxs_lradc_adc_iio_info; > + iio->modes = INDIO_DIRECT_MODE; > + iio->masklength = LRADC_MAX_TOTAL_CHANS; > + > + if (lradc->soc == IMX23_LRADC) { > + iio->channels = mx23_lradc_chan_spec; > + iio->num_channels = ARRAY_SIZE(mx23_lradc_chan_spec); > + irq = mx23_lradc_adc_irq; > + n = IMX23_NUM_IRQ; > + } else { > + iio->channels = mx28_lradc_chan_spec; > + iio->num_channels = ARRAY_SIZE(mx28_lradc_chan_spec); > + irq = mx28_lradc_adc_irq; > + n = IMX28_NUM_IRQ; > + } > + > + for (i = 0; i < n; i++) { > + j = irq[i]; > + ret = devm_request_irq(dev, lradc->irq[j], > + mxs_lradc_adc_handle_irq, > + 0, lradc->irq_name[j], iio); > + if (ret) > + return ret; > + } > + > + ret = mxs_lradc_adc_trigger_init(iio); > + if (ret) > + goto err_trig; > + > + ret = iio_triggered_buffer_setup(iio, &iio_pollfunc_store_time, > + &mxs_lradc_adc_trigger_handler, > + &mxs_lradc_adc_buffer_ops); > + if (ret) > + return ret; > + > + adc->vref_mv = mxs_lradc_adc_vref_mv[lradc->soc]; > + > + /* Populate available ADC input ranges */ > + for (i = 0; i < LRADC_MAX_TOTAL_CHANS; i++) { > + for (s = 0; s < ARRAY_SIZE(adc->scale_avail[i]); s++) { > + /* > + * [s=0] = optional divider by two disabled (default) > + * [s=1] = optional divider by two enabled > + * > + * The scale is calculated by doing: > + * Vref >> (realbits - s) > + * which multiplies by two on the second component > + * of the array. > + */ > + scale_uv = ((u64)adc->vref_mv[i] * 100000000) >> > + (LRADC_RESOLUTION - s); > + adc->scale_avail[i][s].nano = > + do_div(scale_uv, 100000000) * 10; > + adc->scale_avail[i][s].integer = scale_uv; > + } > + } > + > + /* Configure the hardware. */ > + mxs_lradc_adc_hw_init(adc); > + > + /* Register IIO device. */ > + ret = iio_device_register(iio); > + if (ret) { > + dev_err(dev, "Failed to register IIO device\n"); > + goto err_dev; > + } > + > + return 0; > + > +err_dev: > + mxs_lradc_adc_hw_stop(adc); > + mxs_lradc_adc_trigger_remove(iio); > +err_trig: > + iio_triggered_buffer_cleanup(iio); > + return ret; > +} > + > +static int mxs_lradc_adc_remove(struct platform_device *pdev) > +{ > + struct iio_dev *iio = platform_get_drvdata(pdev); > + struct mxs_lradc_adc *adc = iio_priv(iio); > + > + iio_device_unregister(iio); > + mxs_lradc_adc_hw_stop(adc); > + mxs_lradc_adc_trigger_remove(iio); > + iio_triggered_buffer_cleanup(iio); > + > + return 0; > +} > + > +static struct platform_driver mxs_lradc_adc_driver = { > + .driver = { > + .name = DRIVER_NAME_ADC, > + }, > + .probe = mxs_lradc_adc_probe, > + .remove = mxs_lradc_adc_remove, > +}; > + > +module_platform_driver(mxs_lradc_adc_driver); > + > +MODULE_AUTHOR("Marek Vasut "); > +MODULE_DESCRIPTION("Freescale MXS LRADC driver general purpose ADC driver"); > +MODULE_LICENSE("GPL"); > +MODULE_ALIAS("platform:" DRIVER_NAME_ADC); >