From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S941933AbcJYQ1f (ORCPT ); Tue, 25 Oct 2016 12:27:35 -0400 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:14523 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S941921AbcJYQ13 (ORCPT ); Tue, 25 Oct 2016 12:27:29 -0400 From: Fabrice Gasnier To: , , , CC: , , , , , , , , , Subject: [PATCH 02/10] iio: adc: Add stm32 support Date: Tue, 25 Oct 2016 18:25:14 +0200 Message-ID: <1477412722-24061-3-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1477412722-24061-1-git-send-email-fabrice.gasnier@st.com> References: <1477412722-24061-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.48.0.167] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-10-25_15:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch adds support for STMicroelectronics STM32 MCU's analog to digital converter. Signed-off-by: Fabrice Gasnier --- drivers/iio/adc/Kconfig | 2 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/stm32/Kconfig | 34 ++ drivers/iio/adc/stm32/Makefile | 4 + drivers/iio/adc/stm32/stm32-adc.c | 999 ++++++++++++++++++++++++++++++++++++ drivers/iio/adc/stm32/stm32-adc.h | 442 ++++++++++++++++ drivers/iio/adc/stm32/stm32f4-adc.c | 574 +++++++++++++++++++++ 7 files changed, 2056 insertions(+) create mode 100644 drivers/iio/adc/stm32/Kconfig create mode 100644 drivers/iio/adc/stm32/Makefile create mode 100644 drivers/iio/adc/stm32/stm32-adc.c create mode 100644 drivers/iio/adc/stm32/stm32-adc.h create mode 100644 drivers/iio/adc/stm32/stm32f4-adc.c diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 7edcf32..5c96a55 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -583,4 +583,6 @@ config XILINX_XADC The driver can also be build as a module. If so, the module will be called xilinx-xadc. +source "drivers/iio/adc/stm32/Kconfig" + endmenu diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 7a40c04..a9dbf3a 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_AD7791) += ad7791.o obj-$(CONFIG_AD7793) += ad7793.o obj-$(CONFIG_AD7887) += ad7887.o obj-$(CONFIG_AD799X) += ad799x.o +obj-$(CONFIG_ARCH_STM32) += stm32/ obj-$(CONFIG_AT91_ADC) += at91_adc.o obj-$(CONFIG_AT91_SAMA5D2_ADC) += at91-sama5d2_adc.o obj-$(CONFIG_AXP288_ADC) += axp288_adc.o diff --git a/drivers/iio/adc/stm32/Kconfig b/drivers/iio/adc/stm32/Kconfig new file mode 100644 index 0000000..245d037 --- /dev/null +++ b/drivers/iio/adc/stm32/Kconfig @@ -0,0 +1,34 @@ +# +# STM32 familly ADC drivers +# + +config STM32_ADC + tristate + select REGULATOR + select REGULATOR_FIXED_VOLTAGE + select IIO_BUFFER + select IIO_TRIGGERED_BUFFER + help + Say yes here to build the driver for the STMicroelectronics + STM32 analog-to-digital converter (ADC). + + This driver can also be built as a module. If so, the module + will be called stm32-adc. + +config STM32F4_ADC + tristate "STMicroelectronics STM32F4 adc" + depends on ARCH_STM32 || COMPILE_TEST + depends on OF + select STM32_ADC + help + Say yes here to build support for STMicroelectronics stm32f4 Analog + to Digital Converter (ADC). + + This driver can also be built as a module. If so, the module + will be called stm32f4-adc. + +config STM32_ADC_DEBUG + bool "Enable debug for stm32 ADC drivers" + depends on STM32_ADC + help + Say "yes" to enable debug messages, on stm32 ADC drivers. diff --git a/drivers/iio/adc/stm32/Makefile b/drivers/iio/adc/stm32/Makefile new file mode 100644 index 0000000..83e8154 --- /dev/null +++ b/drivers/iio/adc/stm32/Makefile @@ -0,0 +1,4 @@ +# Core +subdir-ccflags-$(CONFIG_STM32_ADC_DEBUG) := -DDEBUG +obj-$(CONFIG_STM32_ADC) += stm32-adc.o +obj-$(CONFIG_STM32F4_ADC) += stm32f4-adc.o diff --git a/drivers/iio/adc/stm32/stm32-adc.c b/drivers/iio/adc/stm32/stm32-adc.c new file mode 100644 index 0000000..1e0850d --- /dev/null +++ b/drivers/iio/adc/stm32/stm32-adc.c @@ -0,0 +1,999 @@ +/* + * This file is part of STM32 ADC driver + * + * Copyright (C) 2016, STMicroelectronics - All Rights Reserved + * Author: Fabrice Gasnier . + * + * License type: GPLv2 + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * 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. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see . + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "stm32-adc.h" + +/** + * stm32_adc_conf_scan_seq() - Build regular or injected channels scan sequence + * @indio_dev: IIO device + * @scan_mask: channels to be converted + * + * Conversion sequence : + * Configure ADC scan sequence based on selected channels in scan_mask. + * Add channels to SQR or JSQR registers, from scan_mask LSB to MSB, then + * program sequence len. + * + * Note: This can be done only when ADC enabled and no conversion is ongoing. + */ +static int stm32_adc_conf_scan_seq(struct iio_dev *indio_dev, + const unsigned long *scan_mask) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + const struct stm32_adc_regs *sq; + const struct iio_chan_spec *chan; + u32 val, bit; + int sq_max, i = 0; + + if (!stm32_adc_is_enabled(adc)) + return -EBUSY; + + if (adc->injected) { + if (stm32_adc_injected_started(adc)) + return -EBUSY; + + sq = adc->common->data->adc_reginfo->jsqr_reg; + sq_max = STM32_ADC_MAX_JSQ; + } else { + if (stm32_adc_regular_started(adc)) + return -EBUSY; + + sq = adc->common->data->adc_reginfo->sqr_regs; + sq_max = STM32_ADC_MAX_SQ; + } + + /* Build sequence for regular or injected channels */ + for_each_set_bit(bit, scan_mask, indio_dev->masklength) { + chan = indio_dev->channels + bit; + /* + * Assign one channel per SQ/JSQ entry in regular/injected + * sequence, starting with SQ1/JSQ1. + */ + i++; + if (i > sq_max) + return -EINVAL; + + dev_dbg(adc->common->dev, "%s chan %d to %s%d\n", + __func__, chan->channel, adc->injected ? "JSQ" : "SQ", + i); + + val = stm32_adc_readl(adc, sq[i].reg); + val &= ~sq[i].mask; + val |= (chan->channel << sq[i].shift) & sq[i].mask; + stm32_adc_writel(adc, sq[i].reg, val); + } + + if (!i) + return -EINVAL; + + /* Sequence len */ + val = stm32_adc_readl(adc, sq[0].reg); + val &= ~sq[0].mask; + val |= ((i - 1) << sq[0].shift) & sq[0].mask; + stm32_adc_writel(adc, sq[0].reg, val); + + return 0; +} + +static int stm32_adc_conf_scan(struct iio_dev *indio_dev, + const unsigned long *scan_mask) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + int ret; + + ret = stm32_adc_clk_sel(adc); + if (ret) { + dev_err(&indio_dev->dev, "Clock sel failed\n"); + return ret; + } + + ret = stm32_adc_enable(adc); + if (ret) { + dev_err(&indio_dev->dev, "Failed to enable adc\n"); + return ret; + } + + ret = stm32_adc_conf_scan_seq(indio_dev, scan_mask); + if (ret) { + dev_err(&indio_dev->dev, "Failed to configure sequence\n"); + goto err_dis; + } + + return 0; + +err_dis: + stm32_adc_disable(adc); + + return ret; +} + +/** + * stm32_adc_get_trig_index() - Get trigger index + * @indio_dev: IIO device + * @trig: trigger + * + * Returns trigger index, if trig matches one of the triggers registered by + * stm32 adc driver, -EINVAL otherwise. + */ +static int stm32_adc_get_trig_index(struct iio_dev *indio_dev, + struct iio_trigger *trig) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + struct iio_trigger *tr; + int i = 0; + + list_for_each_entry(tr, &adc->extrig_list, alloc_list) { + if (tr == trig) + return i; + i++; + } + + return -EINVAL; +} + +/** + * stm32_adc_set_trig() - Set a regular or injected trigger + * @indio_dev: IIO device + * @trig: IIO trigger + * + * Set trigger source/polarity (e.g. SW, or HW with polarity) : + * - if HW trigger disabled (e.g. trig == NULL, conversion launched by sw) + * - if HW trigger enabled, set source & polarity (trigger_pol / jtrigger_pol) + * + * Note: must be called when ADC is enabled + */ +static int stm32_adc_set_trig(struct iio_dev *indio_dev, + struct iio_trigger *trig) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + const struct stm32_adc_trig_info *trig_info; + const struct stm32_adc_trig_reginfo *reginfo; + u32 val, extsel = 0, exten = STM32_EXTEN_SWTRIG; + unsigned long flags; + int ret; + + if (!stm32_adc_is_enabled(adc)) + return -EBUSY; + + if (adc->injected) { + if (stm32_adc_injected_started(adc)) + return -EBUSY; + reginfo = adc->common->data->adc_reginfo->jtrig_reginfo; + trig_info = adc->common->data->jext_triggers; + } else { + if (stm32_adc_regular_started(adc)) + return -EBUSY; + reginfo = adc->common->data->adc_reginfo->trig_reginfo; + trig_info = adc->common->data->ext_triggers; + } + + if (trig) { + ret = stm32_adc_get_trig_index(indio_dev, trig); + if (ret < 0) + return ret; + + /* trigger source */ + extsel = trig_info[ret].extsel; + exten = STM32_EXTEN_HWTRIG_RISING_EDGE; + } + + spin_lock_irqsave(&adc->lock, flags); + val = stm32_adc_readl(adc, reginfo->reg); + val &= ~(reginfo->exten_mask | reginfo->extsel_mask); + val |= (exten << reginfo->exten_shift) & reginfo->exten_mask; + val |= (extsel << reginfo->extsel_shift) & reginfo->extsel_mask; + stm32_adc_writel(adc, reginfo->reg, val); + spin_unlock_irqrestore(&adc->lock, flags); + + return 0; +} + +/** + * stm32_adc_conv_irq_enable() - Unmask end of conversion irq + * @adc: stm32 adc instance + * + * Unmask either eoc or jeoc, depending on injected configuration. + */ +static void stm32_adc_conv_irq_enable(struct stm32_adc *adc) +{ + const struct stm32_adc_reginfo *reginfo = + adc->common->data->adc_reginfo; + u32 mask; + + if (adc->injected) + mask = reginfo->jeocie; + else + mask = reginfo->eocie; + + stm32_adc_set_bits(adc, reginfo->ier, mask); +} + +/** + * stm32_adc_conv_irq_disable() - Mask end of conversion irq + * @adc: stm32 adc instance + * + * Mask either eoc or jeoc, depending on injected configuration. + */ +static void stm32_adc_conv_irq_disable(struct stm32_adc *adc) +{ + const struct stm32_adc_reginfo *reginfo = + adc->common->data->adc_reginfo; + u32 mask; + + if (adc->injected) + mask = reginfo->jeocie; + else + mask = reginfo->eocie; + + stm32_adc_clr_bits(adc, reginfo->ier, mask); +} + +/** + * stm32_adc_single_conv() - perform a single conversion + * @indio_dev: IIO device + * @chan: IIO channel + * @result: conversion result + * + * The function performs a single conversion on a given channel, by + * by: + * - creating scan mask with only one channel + * - using SW trigger + * - then start single conv + */ +static int stm32_adc_single_conv(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + int *val) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + unsigned long *scan_mask; + long timeout; + u16 result; + int ret; + + scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), sizeof(long), + GFP_KERNEL); + if (!scan_mask) + return -ENOMEM; + + set_bit(chan->scan_index, scan_mask); + + reinit_completion(&adc->completion); + + adc->bufi = 0; + adc->num_conv = 1; + adc->buffer = &result; + + ret = stm32_adc_conf_scan(indio_dev, scan_mask); + if (ret) + goto free; + + /* No HW trigger: conversion can be launched in SW */ + ret = stm32_adc_set_trig(indio_dev, NULL); + if (ret) { + dev_err(&indio_dev->dev, "Can't set SW trigger\n"); + goto adc_disable; + } + + stm32_adc_conv_irq_enable(adc); + + ret = stm32_adc_start_conv(adc); + if (ret) { + dev_err(&indio_dev->dev, "Failed to start single conv\n"); + goto irq_disable; + } + + timeout = wait_for_completion_interruptible_timeout( + &adc->completion, STM32_ADC_TIMEOUT); + if (timeout == 0) { + dev_warn(&indio_dev->dev, "Conversion timed out!\n"); + ret = -ETIMEDOUT; + } else if (timeout < 0) { + dev_warn(&indio_dev->dev, "Interrupted conversion!\n"); + ret = -EINTR; + } else { + *val = result & STM32_RESULT_MASK; + ret = IIO_VAL_INT; + } + + if (stm32_adc_stop_conv(adc)) + dev_err(&indio_dev->dev, "stop failed\n"); + +irq_disable: + stm32_adc_conv_irq_disable(adc); + +adc_disable: + stm32_adc_disable(adc); + +free: + kfree(scan_mask); + adc->buffer = NULL; + + return ret; +} + +static int stm32_adc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + int ret = -EINVAL; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + if (chan->type == IIO_VOLTAGE) + ret = stm32_adc_single_conv(indio_dev, chan, val); + iio_device_release_direct_mode(indio_dev); + break; + case IIO_CHAN_INFO_SCALE: + *val = adc->common->vref_mv; + *val2 = chan->scan_type.realbits; + ret = IIO_VAL_FRACTIONAL_LOG2; + break; + default: + break; + } + + return ret; +} + +/** + * stm32_adc_isr() - Treat interrupt for one ADC instance within ADC block + */ +static irqreturn_t stm32_adc_isr(struct stm32_adc *adc) +{ + struct iio_dev *indio_dev = iio_priv_to_dev(adc); + const struct stm32_adc_reginfo *reginfo = + adc->common->data->adc_reginfo; + u32 mask, clr_mask, status = stm32_adc_readl(adc, reginfo->isr); + + if (adc->injected) { + mask = reginfo->jeoc; + clr_mask = mask; + } else { + mask = reginfo->eoc; + /* don't clear 'eoc' as it is cleared when reading 'dr' */ + clr_mask = 0; + } + + /* clear irq */ + stm32_adc_writel(adc, reginfo->isr, status & ~clr_mask); + status &= mask; + + /* Regular data */ + if (status & reginfo->eoc) { + adc->buffer[adc->bufi] = stm32_adc_readl(adc, reginfo->dr); + if (iio_buffer_enabled(indio_dev)) { + adc->bufi++; + if (adc->bufi >= adc->num_conv) { + stm32_adc_conv_irq_disable(adc); + iio_trigger_poll(indio_dev->trig); + } + } else { + complete(&adc->completion); + } + } + + /* Injected data */ + if (status & reginfo->jeoc) { + int i; + + for (i = 0; i < adc->num_conv; i++) { + adc->buffer[i] = stm32_adc_readl(adc, reginfo->jdr[i]); + adc->bufi++; + } + + if (iio_buffer_enabled(indio_dev)) { + stm32_adc_conv_irq_disable(adc); + iio_trigger_poll(indio_dev->trig); + } else { + complete(&adc->completion); + } + } + + /* + * In case end of conversion flags have been handled, this has been + * handled for this ADC instance + */ + if (status) + return IRQ_HANDLED; + + /* This adc instance didn't trigger this interrupt */ + return IRQ_NONE; +} + +/** + * stm32_adc_common_isr() - Common isr for the whole ADC block + * + * There is one IRQ for all ADCs in ADC block, check all instances. + */ +static irqreturn_t stm32_adc_common_isr(int irq, void *data) +{ + struct stm32_adc_common *common = data; + irqreturn_t ret = IRQ_NONE; + struct stm32_adc *adc; + + list_for_each_entry(adc, &common->adc_list, adc_list) + ret |= stm32_adc_isr(adc); + + return ret; +} + +/** + * stm32_adc_validate_trigger() - validate trigger for stm32 adc + * @indio_dev: IIO device + * @trig: new trigger + * + * Returns: 0 if trig matches one of the triggers registered by stm32 adc + * driver, -EINVAL otherwise. + */ +static int stm32_adc_validate_trigger(struct iio_dev *indio_dev, + struct iio_trigger *trig) +{ + return stm32_adc_get_trig_index(indio_dev, trig) < 0 ? -EINVAL : 0; +} + +static int stm32_adc_update_scan_mode(struct iio_dev *indio_dev, + const unsigned long *scan_mask) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + int ret; + u32 bit; + + adc->num_conv = 0; + for_each_set_bit(bit, scan_mask, indio_dev->masklength) + adc->num_conv++; + + ret = stm32_adc_conf_scan(indio_dev, scan_mask); + if (ret) + return ret; + + return 0; +} + +static int stm32_adc_of_xlate(struct iio_dev *indio_dev, + const struct of_phandle_args *iiospec) +{ + int i; + + for (i = 0; i < indio_dev->num_channels; i++) + if (indio_dev->channels[i].channel == iiospec->args[0]) + return i; + + return -EINVAL; +} + +/** + * stm32_adc_debugfs_reg_access - read or write register value + * + * To read a value from an ADC register: + * echo [ADC reg offset] > direct_reg_access + * cat direct_reg_access + * + * To write a value in a ADC register: + * echo [ADC_reg_offset] [value] > direct_reg_access + */ +static int stm32_adc_debugfs_reg_access(struct iio_dev *indio_dev, + unsigned reg, unsigned writeval, + unsigned *readval) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + + if (!readval) + stm32_adc_writel(adc, reg, writeval); + else + *readval = stm32_adc_readl(adc, reg); + + return 0; +} + +static const struct iio_info stm32_adc_iio_info = { + .read_raw = stm32_adc_read_raw, + .validate_trigger = stm32_adc_validate_trigger, + .update_scan_mode = stm32_adc_update_scan_mode, + .debugfs_reg_access = stm32_adc_debugfs_reg_access, + .of_xlate = stm32_adc_of_xlate, + .driver_module = THIS_MODULE, +}; + +static int stm32_adc_buffer_postdisable(struct iio_dev *indio_dev) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + + stm32_adc_disable(adc); + + return 0; +} + +static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = { + .postenable = &iio_triggered_buffer_postenable, + .predisable = &iio_triggered_buffer_predisable, + .postdisable = &stm32_adc_buffer_postdisable, +}; + +static int stm32_adc_validate_device(struct iio_trigger *trig, + struct iio_dev *indio_dev) +{ + struct iio_dev *indio = iio_trigger_get_drvdata(trig); + + return indio != indio_dev ? -EINVAL : 0; +} + +static int stm32_adc_set_trigger_state(struct iio_trigger *trig, + bool state) +{ + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); + struct stm32_adc *adc = iio_priv(indio_dev); + int ret; + + if (state) { + /* Reset adc buffer index */ + adc->bufi = 0; + + /* Allocate adc buffer */ + adc->buffer = kzalloc(indio_dev->scan_bytes, GFP_KERNEL); + if (!adc->buffer) + return -ENOMEM; + + ret = stm32_adc_set_trig(indio_dev, trig); + if (ret) { + dev_err(&indio_dev->dev, "Can't set trigger\n"); + goto err_buffer_free; + } + + stm32_adc_conv_irq_enable(adc); + + ret = stm32_adc_start_conv(adc); + if (ret) { + dev_err(&indio_dev->dev, "Failed to start\n"); + goto err_irq_trig_disable; + } + } else { + ret = stm32_adc_stop_conv(adc); + if (ret < 0) { + dev_err(&indio_dev->dev, "Failed to stop\n"); + return ret; + } + + stm32_adc_conv_irq_disable(adc); + + ret = stm32_adc_set_trig(indio_dev, NULL); + if (ret) + dev_warn(&indio_dev->dev, "Can't clear trigger\n"); + + kfree(adc->buffer); + adc->buffer = NULL; + } + + return 0; + +err_irq_trig_disable: + stm32_adc_conv_irq_disable(adc); + stm32_adc_set_trig(indio_dev, NULL); + +err_buffer_free: + kfree(adc->buffer); + adc->buffer = NULL; + + return ret; +} + +static const struct iio_trigger_ops stm32_adc_trigger_ops = { + .owner = THIS_MODULE, + .validate_device = stm32_adc_validate_device, + .set_trigger_state = stm32_adc_set_trigger_state, +}; + +static irqreturn_t stm32_adc_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct stm32_adc *adc = iio_priv(indio_dev); + + dev_dbg(&indio_dev->dev, "%s bufi=%d\n", __func__, adc->bufi); + + /* reset buffer index */ + adc->bufi = 0; + iio_push_to_buffers_with_timestamp(indio_dev, adc->buffer, + pf->timestamp); + + iio_trigger_notify_done(indio_dev->trig); + + /* re-enable eoc irq */ + stm32_adc_conv_irq_enable(adc); + + return IRQ_HANDLED; +} + +static void stm32_adc_trig_unregister(struct iio_dev *indio_dev) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + struct iio_trigger *trig, *_t; + + list_for_each_entry_safe(trig, _t, &adc->extrig_list, alloc_list) { + iio_trigger_unregister(trig); + list_del(&trig->alloc_list); + } +} + +static int stm32_adc_trig_register(struct iio_dev *indio_dev) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + struct stm32_adc_common *common = adc->common; + const struct stm32_adc_trig_info *ext = common->data->ext_triggers; + struct iio_trigger *trig; + int i, ret = 0; + + if (adc->injected) + ext = common->data->jext_triggers; + else + ext = common->data->ext_triggers; + + for (i = 0; ext && ext[i].name; i++) { + trig = devm_iio_trigger_alloc(common->dev, "%s_%s%d_%s", + indio_dev->name, + adc->injected ? "jext" : "ext", + ext[i].extsel, ext[i].name); + if (!trig) { + dev_err(common->dev, "trig %s_%s%d_%s alloc failed\n", + indio_dev->name, + adc->injected ? "jext" : "ext", + ext[i].extsel, ext[i].name); + ret = -ENOMEM; + goto err; + } + + trig->dev.parent = common->dev; + trig->ops = &stm32_adc_trigger_ops; + iio_trigger_set_drvdata(trig, indio_dev); + + ret = iio_trigger_register(trig); + if (ret) { + dev_err(common->dev, + "trig %s_%s%d_%s register failed\n", + indio_dev->name, + adc->injected ? "jext" : "ext", + ext[i].extsel, ext[i].name); + goto err; + } + + list_add_tail(&trig->alloc_list, &adc->extrig_list); + } + + return 0; +err: + stm32_adc_trig_unregister(indio_dev); + + return ret; +} + +static void stm32_adc_chan_init_one(struct iio_dev *indio_dev, + struct iio_chan_spec *chan, + const struct stm32_adc_chan_spec *channel, + int scan_index) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + + chan->type = channel->type; + chan->channel = channel->channel; + chan->datasheet_name = channel->name; + chan->extend_name = channel->name; + chan->scan_index = scan_index; + chan->indexed = 1; + chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); + chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE); + chan->scan_type.sign = 'u'; + chan->scan_type.realbits = adc->common->data->highres; + chan->scan_type.storagebits = STM32_STORAGEBITS; + chan->scan_type.shift = 0; +} + +static int stm32_adc_chan_of_init(struct iio_dev *indio_dev, + const struct stm32_adc_info *adc_info) +{ + struct stm32_adc *adc = iio_priv(indio_dev); + struct device_node *node = indio_dev->dev.of_node; + struct property *prop; + const __be32 *cur; + struct iio_chan_spec *channels; + int scan_index = 0, num_channels = 0; + u32 val; + + of_property_for_each_u32(node, "st,adc-channels", prop, cur, val) + num_channels++; + + channels = devm_kcalloc(&indio_dev->dev, num_channels, + sizeof(struct iio_chan_spec), GFP_KERNEL); + if (!channels) + return -ENOMEM; + + of_property_for_each_u32(node, "st,adc-channels", prop, cur, val) { + stm32_adc_chan_init_one(indio_dev, &channels[scan_index], + &adc_info->channels[val], + scan_index); + scan_index++; + } + + adc->max_channels = adc_info->max_channels; + indio_dev->num_channels = scan_index; + indio_dev->channels = channels; + + return 0; +} + +static int stm32_adc_register(struct stm32_adc_common *common, + struct device_node *child) +{ + struct iio_dev *indio_dev; + struct stm32_adc *adc; + int i, ret; + u32 reg; + + ret = of_property_read_u32(child, "reg", ®); + if (ret != 0) { + dev_err(common->dev, "missing reg property\n"); + return -EINVAL; + } + + for (i = 0; common->data->adc_info[i].channels; i++) + if (common->data->adc_info[i].reg == reg) + break; + + if (i >= STM32_ADC_ID_MAX || !common->data->adc_info[i].channels) { + dev_err(common->dev, "bad adc reg offset\n"); + return -ENOENT; + } + + indio_dev = devm_iio_device_alloc(common->dev, sizeof(*adc)); + if (!indio_dev) { + dev_err(common->dev, "iio device allocation failed\n"); + return -ENOMEM; + } + + adc = iio_priv(indio_dev); + adc->id = i; + adc->offset = reg; + adc->common = common; + INIT_LIST_HEAD(&adc->extrig_list); + spin_lock_init(&adc->lock); + init_completion(&adc->completion); + + if (child->name) + indio_dev->name = child->name; + else + indio_dev->name = common->data->adc_info[i].name; + indio_dev->dev.parent = common->dev; + indio_dev->dev.of_node = child; + indio_dev->info = &stm32_adc_iio_info; + indio_dev->modes = INDIO_DIRECT_MODE; + + if (of_property_read_bool(child, "st,injected")) { + dev_dbg(common->dev, "%s Configured to use injected\n", + indio_dev->name); + adc->injected = true; + } + + adc->clk = of_clk_get(child, 0); + if (IS_ERR(adc->clk)) { + adc->clk = NULL; + dev_dbg(common->dev, "No child clk found\n"); + } else { + ret = clk_prepare_enable(adc->clk); + if (ret < 0) + goto err_clk_put; + } + + ret = stm32_adc_chan_of_init(indio_dev, &common->data->adc_info[i]); + if (ret < 0) { + dev_err(common->dev, "iio channels init failed\n"); + goto err_clk_disable; + } + + ret = stm32_adc_trig_register(indio_dev); + if (ret) + goto err_clk_disable; + + ret = iio_triggered_buffer_setup(indio_dev, + &iio_pollfunc_store_time, + &stm32_adc_trigger_handler, + &iio_triggered_buffer_setup_ops); + if (ret) { + dev_err(common->dev, "buffer setup failed\n"); + goto err_trig_unregister; + } + + ret = iio_device_register(indio_dev); + if (ret) { + dev_err(common->dev, "iio dev register failed\n"); + goto err_buffer_cleanup; + } + + list_add_tail(&adc->adc_list, &common->adc_list); + + return 0; + +err_buffer_cleanup: + iio_triggered_buffer_cleanup(indio_dev); + +err_trig_unregister: + stm32_adc_trig_unregister(indio_dev); + +err_clk_disable: + if (adc->clk) + clk_disable_unprepare(adc->clk); + +err_clk_put: + if (adc->clk) + clk_put(adc->clk); + + return ret; +} + +static void stm32_adc_unregister(struct stm32_adc *adc) +{ + struct iio_dev *indio_dev = iio_priv_to_dev(adc); + + iio_device_unregister(indio_dev); + iio_triggered_buffer_cleanup(indio_dev); + stm32_adc_trig_unregister(indio_dev); + if (adc->clk) { + clk_disable_unprepare(adc->clk); + clk_put(adc->clk); + } +} + +int stm32_adc_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node, *child; + struct device *dev = &pdev->dev; + const struct of_device_id *match; + struct stm32_adc_common *common; + struct stm32_adc *adc; + struct resource *res; + int ret; + + match = of_match_device(dev->driver->of_match_table, &pdev->dev); + if (!match || !match->data) { + dev_err(&pdev->dev, "compatible data not provided\n"); + return -EINVAL; + } + + common = devm_kzalloc(&pdev->dev, sizeof(*common), GFP_KERNEL); + if (!common) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + common->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(common->base)) + return PTR_ERR(common->base); + + common->data = match->data; + common->dev = &pdev->dev; + platform_set_drvdata(pdev, common); + mutex_init(&common->lock); + INIT_LIST_HEAD(&common->adc_list); + + common->vref = devm_regulator_get(&pdev->dev, "vref"); + if (IS_ERR(common->vref)) { + ret = PTR_ERR(common->vref); + dev_err(&pdev->dev, "vref get failed, %d\n", ret); + return ret; + } + + ret = regulator_enable(common->vref); + if (ret < 0) { + dev_err(&pdev->dev, "vref enable failed\n"); + return ret; + } + + ret = regulator_get_voltage(common->vref); + if (ret < 0) { + dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret); + goto err_regulator_disable; + } + common->vref_mv = ret / 1000; + dev_dbg(&pdev->dev, "vref+=%dmV\n", common->vref_mv); + + common->aclk = devm_clk_get(&pdev->dev, "adc"); + if (IS_ERR(common->aclk)) { + ret = PTR_ERR(common->aclk); + dev_err(&pdev->dev, "Can't get 'adc' clock\n"); + goto err_regulator_disable; + } + + ret = clk_prepare_enable(common->aclk); + if (ret < 0) { + dev_err(common->dev, "adc clk enable failed\n"); + goto err_regulator_disable; + } + + common->irq = platform_get_irq(pdev, 0); + if (common->irq < 0) { + dev_err(&pdev->dev, "failed to get irq\n"); + ret = common->irq; + goto err_clk_disable; + } + + ret = devm_request_irq(&pdev->dev, common->irq, stm32_adc_common_isr, + 0, pdev->name, common); + if (ret) { + dev_err(&pdev->dev, "failed to request irq\n"); + goto err_clk_disable; + } + + /* Parse adc child nodes to retrieve master/slave instances data */ + for_each_available_child_of_node(np, child) { + ret = stm32_adc_register(common, child); + if (ret) + goto err_unregister; + } + + dev_info(&pdev->dev, "registered\n"); + + return 0; + +err_unregister: + list_for_each_entry(adc, &common->adc_list, adc_list) + stm32_adc_unregister(adc); + +err_clk_disable: + clk_disable_unprepare(common->aclk); + +err_regulator_disable: + regulator_disable(common->vref); + + return ret; +} +EXPORT_SYMBOL_GPL(stm32_adc_probe); + +int stm32_adc_remove(struct platform_device *pdev) +{ + struct stm32_adc_common *common = platform_get_drvdata(pdev); + struct stm32_adc *adc; + + list_for_each_entry(adc, &common->adc_list, adc_list) + stm32_adc_unregister(adc); + clk_disable_unprepare(common->aclk); + regulator_disable(common->vref); + + return 0; +} +EXPORT_SYMBOL_GPL(stm32_adc_remove); + +MODULE_AUTHOR("Fabrice Gasnier "); +MODULE_DESCRIPTION("STMicroelectronics STM32 ADC driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/iio/adc/stm32/stm32-adc.h b/drivers/iio/adc/stm32/stm32-adc.h new file mode 100644 index 0000000..0be603c --- /dev/null +++ b/drivers/iio/adc/stm32/stm32-adc.h @@ -0,0 +1,442 @@ +/* + * This file is part of STM32 ADC driver + * + * Copyright (C) 2016, STMicroelectronics - All Rights Reserved + * Author: Fabrice Gasnier . + * + * License type: GPLv2 + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * 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. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see . + */ + +#ifndef __STM32_ADC_H +#define __STM32_ADC_H + +/* + * STM32 - ADC global register map + * ________________________________________________________ + * | Offset | Register | + * -------------------------------------------------------- + * | 0x000 | Master ADC1 | + * -------------------------------------------------------- + * | 0x100 | Slave ADC2 | + * -------------------------------------------------------- + * | 0x200 | Slave ADC3 | + * -------------------------------------------------------- + * | 0x300 | Master & Slave common regs | + * -------------------------------------------------------- + */ +#define STM32_ADCX_COMN_OFFSET 0x300 +#define STM32_ADC_ID_MAX 3 +#define STM32_ADC_MAX_SQ 16 /* SQ1..SQ16 */ +#define STM32_ADC_MAX_JSQ 4 /* JSQ1..JSQ4 */ + +/* STM32 value masks */ +#define STM32_RESULT_MASK GENMASK(15, 0) +#define STM32_STORAGEBITS 16 + +/* External trigger enable for regular or injected channels (exten/jexten) */ +enum stm32_adc_exten { + STM32_EXTEN_SWTRIG, + STM32_EXTEN_HWTRIG_RISING_EDGE, + STM32_EXTEN_HWTRIG_FALLING_EDGE, + STM32_EXTEN_HWTRIG_BOTH_EDGES, +}; + +enum stm32_adc_extsel { + STM32_EXT0, + STM32_EXT1, + STM32_EXT2, + STM32_EXT3, + STM32_EXT4, + STM32_EXT5, + STM32_EXT6, + STM32_EXT7, + STM32_EXT8, + STM32_EXT9, + STM32_EXT10, + STM32_EXT11, + STM32_EXT12, + STM32_EXT13, + STM32_EXT14, + STM32_EXT15, + STM32_EXT16, + STM32_EXT17, + STM32_EXT18, + STM32_EXT19, + STM32_EXT20, + STM32_EXT21, + STM32_EXT22, + STM32_EXT23, + STM32_EXT24, + STM32_EXT25, + STM32_EXT26, + STM32_EXT27, + STM32_EXT28, + STM32_EXT29, + STM32_EXT30, + STM32_EXT31, +}; + +enum stm32_adc_jextsel { + STM32_JEXT0, + STM32_JEXT1, + STM32_JEXT2, + STM32_JEXT3, + STM32_JEXT4, + STM32_JEXT5, + STM32_JEXT6, + STM32_JEXT7, + STM32_JEXT8, + STM32_JEXT9, + STM32_JEXT10, + STM32_JEXT11, + STM32_JEXT12, + STM32_JEXT13, + STM32_JEXT14, + STM32_JEXT15, + STM32_JEXT16, + STM32_JEXT17, + STM32_JEXT18, + STM32_JEXT19, + STM32_JEXT20, + STM32_JEXT21, + STM32_JEXT22, + STM32_JEXT23, + STM32_JEXT24, + STM32_JEXT25, + STM32_JEXT26, + STM32_JEXT27, + STM32_JEXT28, + STM32_JEXT29, + STM32_JEXT30, + STM32_JEXT31, +}; + +#define STM32_ADC_TIMEOUT_US 100000 +#define STM32_ADC_TIMEOUT (msecs_to_jiffies(STM32_ADC_TIMEOUT_US / 1000)) + +/** + * struct stm32_adc_chan_spec - specification of stm32 adc channel + * @type: IIO channel type + * @channel: channel number (single ended) + * @name: channel name (single ended) + */ +struct stm32_adc_chan_spec { + enum iio_chan_type type; + int channel; + const char *name; +}; + +/** + * struct stm32_adc_trig_info - ADC trigger info + * @extsel: trigger selection for regular or injected + * @name: name of the trigger, corresponding to its source + */ +struct stm32_adc_trig_info { + u32 extsel; + const char *name; +}; + +/** + * struct stm32_adc_info - stm32 ADC, per instance config data + * @name: default name for this instance (like "adc1") + * @reg: reg offset for this instance (e.g. 0x0 for adc1...) + * @channels: Reference to stm32 channels spec + * @max_channels: Number of single ended channels + */ +struct stm32_adc_info { + const char *name; + u32 reg; + const struct stm32_adc_chan_spec *channels; + int max_channels; +}; + +/** + * stm32_adc_regs - stm32 ADC misc registers & bitfield desc + * @reg: register offset + * @mask: bitfield mask + * @shift: left shift + */ +struct stm32_adc_regs { + int reg; + int mask; + int shift; +}; + +/** + * stm32_adc_trig_reginfo - stm32 ADC trigger control registers description + * @reg: trigger control register offset (exten/jexten) + * @exten_mask: external trigger en/polarity mask in @reg + * @exten_shift: external trigger en/polarity shift in @reg + * @extsel_mask: external trigger source mask in @reg + * @extsel_shift: external trigger source shift in @reg + */ +struct stm32_adc_trig_reginfo { + u32 reg; + u32 exten_mask; + u32 exten_shift; + u32 extsel_mask; + u32 extsel_shift; +}; + +/** + * struct stm32_adc_reginfo - stm32 ADC registers description + * @isr: interrupt status register offset + * @eoc: end of conversion mask in @isr + * @jeoc: end of injected conversion sequence mask in @isr + * @ier: interrupt enable register offset + * @eocie: end of conversion interrupt enable mask in @ier + * @jeocie: end of injected conversion sequence interrupt en mask + * @dr: data register offset + * @jdr: injected data registers offsets + * @sqr_regs: Regular sequence registers description + * @jsqr_reg: Injected sequence register description + * @trig_reginfo: regular trigger control registers description + * @jtrig_reginfo: injected trigger control registers description + */ +struct stm32_adc_reginfo { + u32 isr; + u32 eoc; + u32 jeoc; + u32 ier; + u32 eocie; + u32 jeocie; + u32 dr; + u32 jdr[4]; + const struct stm32_adc_regs *sqr_regs; + const struct stm32_adc_regs *jsqr_reg; + const struct stm32_adc_trig_reginfo *trig_reginfo; + const struct stm32_adc_trig_reginfo *jtrig_reginfo; +}; + +struct stm32_adc; + +/** + * struct stm32_adc_ops - stm32 ADC, compatible dependent data + * - stm32 ADC may work as single ADC, or as tightly coupled master/slave ADCs. + * + * @adc_info: Array spec for stm32 adc master/slaves instances + * @ext_triggers: Reference to trigger info for regular channels + * @jext_triggers: Reference to trigger info for injected channels + * @adc_reginfo: stm32 ADC registers description + * @highres: Max resolution + * @max_clock_rate: Max input clock rate + * @clk_sel: routine to select common clock and prescaler + * @start_conv: routine to start conversions + * @stop_conv: routine to stop conversions + * @is_started: routine to get adc 'started' state + * @regular_started routine to check regular conversions status + * @injected_started routine to check injected conversions status + * @enable: optional routine to enable stm32 adc + * @disable: optional routine to disable stm32 adc + * @is_enabled reports enabled state + */ +struct stm32_adc_ops { + const struct stm32_adc_info *adc_info; + const struct stm32_adc_trig_info *ext_triggers; + const struct stm32_adc_trig_info *jext_triggers; + const struct stm32_adc_reginfo *adc_reginfo; + int highres; + unsigned long max_clock_rate; + int (*clk_sel)(struct stm32_adc *adc); + int (*start_conv)(struct stm32_adc *adc); + int (*stop_conv)(struct stm32_adc *adc); + bool (*is_started)(struct stm32_adc *adc); + bool (*regular_started)(struct stm32_adc *adc); + bool (*injected_started)(struct stm32_adc *adc); + int (*enable)(struct stm32_adc *adc); + void (*disable)(struct stm32_adc *adc); + bool (*is_enabled)(struct stm32_adc *adc); +}; + +struct stm32_adc_common; + +/** + * struct stm32_adc - private data of each ADC IIO instance + * @common: reference to ADC block common data + * @adc_list: current ADC entry in common ADC list + * @id: ADC instance number (e.g. adc 1, 2 or 3) + * @offset: ADC instance register offset in ADC block + * @max_channels: Max channels number for this ADC. + * @extrig_list: External trigger list (for regular channel) + * @completion: end of single conversion completion + * @buffer: data buffer + * @bufi: data buffer index + * @num_conv: expected number of scan conversions + * @injected: use injected channels on this adc + * @lock: spinlock + * @clk: optional adc clock, for this adc instance + * @calib: optional calibration data + * @en: emulates enabled state on some stm32 adc + */ +struct stm32_adc { + struct stm32_adc_common *common; + struct list_head adc_list; + int id; + int offset; + int max_channels; + struct list_head extrig_list; + struct completion completion; + u16 *buffer; + int bufi; + int num_conv; + bool injected; + spinlock_t lock; /* interrupt lock */ + struct clk *clk; + void *calib; + bool en; +}; + +/** + * struct stm32_adc_common - private data of ADC driver, common to all + * ADC instances (ADC block) + * @dev: device for this controller + * @base: control registers base cpu addr + * @irq: Common irq line for all adc instances + * @data: STM32 dependent data from compatible + * @adc_list: list of all stm32 ADC in this ADC block + * @aclk: common clock for the analog circuitry + * @vref: regulator reference + * @vref_mv: vref voltage (mv) + * @lock: mutex + */ +struct stm32_adc_common { + struct device *dev; + void __iomem *base; + int irq; + const struct stm32_adc_ops *data; + struct list_head adc_list; + struct clk *aclk; + struct regulator *vref; + int vref_mv; + struct mutex lock; /* read_raw lock */ +}; + +/* Helper routines */ +static inline int stm32_adc_start_conv(struct stm32_adc *adc) +{ + return adc->common->data->start_conv(adc); +} + +static inline int stm32_adc_stop_conv(struct stm32_adc *adc) +{ + return adc->common->data->stop_conv(adc); +} + +static inline bool stm32_adc_is_started(struct stm32_adc *adc) +{ + return adc->common->data->is_started(adc); +} + +static inline bool stm32_adc_regular_started(struct stm32_adc *adc) +{ + return adc->common->data->regular_started(adc); +} + +static inline bool stm32_adc_injected_started(struct stm32_adc *adc) +{ + return adc->common->data->injected_started(adc); +} + +static inline bool stm32_adc_clk_sel(struct stm32_adc *adc) +{ + return adc->common->data->clk_sel(adc); +} + +static inline int stm32_adc_enable(struct stm32_adc *adc) +{ + if (adc->common->data->enable) + return adc->common->data->enable(adc); + + adc->en = true; + + return 0; +} + +static inline bool stm32_adc_is_enabled(struct stm32_adc *adc) +{ + if (adc->common->data->is_enabled) + return adc->common->data->is_enabled(adc); + else + return adc->en; +} + +static inline void stm32_adc_disable(struct stm32_adc *adc) +{ + /* Check there is no regular or injected on-going conversions */ + if (stm32_adc_is_started(adc)) + return; + + if (adc->common->data->disable) + adc->common->data->disable(adc); + else + adc->en = false; +} + +/* STM32 ADC registers access routines */ +static inline u32 stm32_adc_common_readl(struct stm32_adc_common *com, u32 reg) +{ + u32 val = readl_relaxed(com->base + reg); + + return val; +} + +static inline void stm32_adc_common_writel(struct stm32_adc_common *com, + u32 reg, u32 val) +{ + writel_relaxed(val, com->base + reg); +} + +static inline u32 stm32_adc_readl(struct stm32_adc *adc, u32 reg) +{ + u32 val = readl_relaxed(adc->common->base + adc->offset + reg); + + return val; +} + +#define stm32_adc_readl_addr(addr) stm32_adc_readl(adc, addr) + +#define stm32_adc_readl_poll_timeout(reg, val, cond, sleep_us, timeout_us) \ + readx_poll_timeout(stm32_adc_readl_addr, reg, val, \ + cond, sleep_us, timeout_us) + +static inline void stm32_adc_writel(struct stm32_adc *adc, u32 reg, u32 val) +{ + writel_relaxed(val, adc->common->base + adc->offset + reg); +} + +static inline void stm32_adc_set_bits(struct stm32_adc *adc, u32 reg, u32 bits) +{ + unsigned long flags; + + spin_lock_irqsave(&adc->lock, flags); + stm32_adc_writel(adc, reg, stm32_adc_readl(adc, reg) | bits); + spin_unlock_irqrestore(&adc->lock, flags); +} + +static inline void stm32_adc_clr_bits(struct stm32_adc *adc, u32 reg, u32 bits) +{ + unsigned long flags; + + spin_lock_irqsave(&adc->lock, flags); + stm32_adc_writel(adc, reg, stm32_adc_readl(adc, reg) & ~bits); + spin_unlock_irqrestore(&adc->lock, flags); +} + +/* STM32 common extended attributes */ +extern const struct iio_enum stm32_adc_trig_pol; +int stm32_adc_probe(struct platform_device *pdev); +int stm32_adc_remove(struct platform_device *pdev); + +#endif diff --git a/drivers/iio/adc/stm32/stm32f4-adc.c b/drivers/iio/adc/stm32/stm32f4-adc.c new file mode 100644 index 0000000..147fe9c --- /dev/null +++ b/drivers/iio/adc/stm32/stm32f4-adc.c @@ -0,0 +1,574 @@ +/* + * This file is part of STM32F4 ADC driver + * + * Copyright (C) 2016, STMicroelectronics - All Rights Reserved + * Author: Fabrice Gasnier . + * + * License type: GPLv2 + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * 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. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see . + */ + +#include +#include +#include +#include +#include +#include "stm32-adc.h" + +/* + * STM32F4 - ADC global register map + * ________________________________________________________ + * | Offset | Register | + * -------------------------------------------------------- + * | 0x000 | Master ADC1 | + * -------------------------------------------------------- + * | 0x100 | Slave ADC2 | + * -------------------------------------------------------- + * | 0x200 | Slave ADC3 | + * -------------------------------------------------------- + * | 0x300 | Master & Slave common regs | + * -------------------------------------------------------- + */ + +/* STM32F4 - Registers for each ADC instance */ +#define STM32F4_ADCX_SR 0x00 +#define STM32F4_ADCX_CR1 0x04 +#define STM32F4_ADCX_CR2 0x08 +#define STM32F4_ADCX_SMPR1 0x0C +#define STM32F4_ADCX_SMPR2 0x10 +#define STM32F4_ADCX_HTR 0x24 +#define STM32F4_ADCX_LTR 0x28 +#define STM32F4_ADCX_SQR1 0x2C +#define STM32F4_ADCX_SQR2 0x30 +#define STM32F4_ADCX_SQR3 0x34 +#define STM32F4_ADCX_JSQR 0x38 +#define STM32F4_ADCX_JDR1 0x3C +#define STM32F4_ADCX_JDR2 0x40 +#define STM32F4_ADCX_JDR3 0x44 +#define STM32F4_ADCX_JDR4 0x48 +#define STM32F4_ADCX_DR 0x4C + +/* STM32 - Master & slave registers (common for all instances: 1, 2 & 3) */ +#define STM32F4_ADC_CSR (STM32_ADCX_COMN_OFFSET + 0x00) +#define STM32F4_ADC_CCR (STM32_ADCX_COMN_OFFSET + 0x04) +#define STM32F4_ADC_CDR (STM32_ADCX_COMN_OFFSET + 0x08) + +/* STM32F4_ADCX_SR - bit fields */ +#define STM32F4_OVR BIT(5) +#define STM32F4_STRT BIT(4) +#define STM32F4_JSTRT BIT(3) +#define STM32F4_JEOC BIT(2) +#define STM32F4_EOC BIT(1) +#define STM32F4_AWD BIT(0) + +/* STM32F4_ADCX_CR1 - bit fields */ +#define STM32F4_OVRIE BIT(26) +#define STM32F4_RES_SHIFT 24 +#define STM32F4_RES_MASK GENMASK(25, 24) +#define STM32F4_AWDEN BIT(23) +#define STM32F4_JAWDEN BIT(22) +#define STM32F4_DISCNUM_SHIFT 13 +#define STM32F4_DISCNUM_MASK GENMASK(15, 13) +#define STM32F4_JDISCEN BIT(12) +#define STM32F4_DISCEN BIT(11) +#define STM32F4_JAUTO BIT(10) +#define STM32F4_AWDSGL BIT(9) +#define STM32F4_SCAN BIT(8) +#define STM32F4_JEOCIE BIT(7) +#define STM32F4_AWDIE BIT(6) +#define STM32F4_EOCIE BIT(5) +#define STM32F4_AWDCH_SHIFT 0 +#define STM32F4_AWDCH_MASK GENMASK(4, 0) + +/* STM32F4_ADCX_CR2 - bit fields */ +#define STM32F4_SWSTART BIT(30) +#define STM32F4_EXTEN_SHIFT 28 +#define STM32F4_EXTEN_MASK GENMASK(29, 28) +#define STM32F4_EXTSEL_SHIFT 24 +#define STM32F4_EXTSEL_MASK GENMASK(27, 24) +#define STM32F4_JSWSTART BIT(22) +#define STM32F4_JEXTEN_SHIFT 20 +#define STM32F4_JEXTEN_MASK GENMASK(21, 20) +#define STM32F4_JEXTSEL_SHIFT 16 +#define STM32F4_JEXTSEL_MASK GENMASK(19, 16) +#define STM32F4_ALIGN BIT(11) +#define STM32F4_EOCS BIT(10) +#define STM32F4_DDS BIT(9) +#define STM32F4_DMA BIT(8) +#define STM32F4_CONT BIT(1) +#define STM32F4_ADON BIT(0) + +/* STM32F4_ADCX_SMPR1 - bit fields */ +#define STM32F4_SMP18_SHIFT 24 +#define STM32F4_SMP18_MASK GENMASK(26, 24) +#define STM32F4_SMP17_SHIFT 21 +#define STM32F4_SMP17_MASK GENMASK(23, 21) +#define STM32F4_SMP16_SHIFT 18 +#define STM32F4_SMP16_MASK GENMASK(20, 18) +#define STM32F4_SMP15_SHIFT 15 +#define STM32F4_SMP15_MASK GENMASK(17, 15) +#define STM32F4_SMP14_SHIFT 12 +#define STM32F4_SMP14_MASK GENMASK(14, 12) +#define STM32F4_SMP13_SHIFT 9 +#define STM32F4_SMP13_MASK GENMASK(11, 9) +#define STM32F4_SMP12_SHIFT 6 +#define STM32F4_SMP12_MASK GENMASK(8, 6) +#define STM32F4_SMP11_SHIFT 3 +#define STM32F4_SMP11_MASK GENMASK(5, 3) +#define STM32F4_SMP10_SHIFT 0 +#define STM32F4_SMP10_MASK GENMASK(2, 0) + +/* STM32F4_ADCX_SMPR2 - bit fields */ +#define STM32F4_SMP9_SHIFT 27 +#define STM32F4_SMP9_MASK GENMASK(29, 27) +#define STM32F4_SMP8_SHIFT 24 +#define STM32F4_SMP8_MASK GENMASK(26, 24) +#define STM32F4_SMP7_SHIFT 21 +#define STM32F4_SMP7_MASK GENMASK(23, 21) +#define STM32F4_SMP6_SHIFT 18 +#define STM32F4_SMP6_MASK GENMASK(20, 18) +#define STM32F4_SMP5_SHIFT 15 +#define STM32F4_SMP5_MASK GENMASK(17, 15) +#define STM32F4_SMP4_SHIFT 12 +#define STM32F4_SMP4_MASK GENMASK(14, 12) +#define STM32F4_SMP3_SHIFT 9 +#define STM32F4_SMP3_MASK GENMASK(11, 9) +#define STM32F4_SMP2_SHIFT 6 +#define STM32F4_SMP2_MASK GENMASK(8, 6) +#define STM32F4_SMP1_SHIFT 3 +#define STM32F4_SMP1_MASK GENMASK(5, 3) +#define STM32F4_SMP0_SHIFT 0 +#define STM32F4_SMP0_MASK GENMASK(2, 0) +enum stm32f4_adc_smpr { + STM32F4_SMPR_3_CK_CYCLES, + STM32F4_SMPR_15_CK_CYCLES, + STM32F4_SMPR_28_CK_CYCLES, + STM32F4_SMPR_56_CK_CYCLES, + STM32F4_SMPR_84_CK_CYCLES, + STM32F4_SMPR_112_CK_CYCLES, + STM32F4_SMPR_144_CK_CYCLES, + STM32F4_SMPR_480_CK_CYCLES, +}; + +/* STM32F4_ADCX_SQR1 - bit fields */ +#define STM32F4_L_SHIFT 20 +#define STM32F4_L_MASK GENMASK(23, 20) +#define STM32F4_SQ16_SHIFT 15 +#define STM32F4_SQ16_MASK GENMASK(19, 15) +#define STM32F4_SQ15_SHIFT 10 +#define STM32F4_SQ15_MASK GENMASK(14, 10) +#define STM32F4_SQ14_SHIFT 5 +#define STM32F4_SQ14_MASK GENMASK(9, 5) +#define STM32F4_SQ13_SHIFT 0 +#define STM32F4_SQ13_MASK GENMASK(4, 0) + +/* STM32F4_ADCX_SQR2 - bit fields */ +#define STM32F4_SQ12_SHIFT 25 +#define STM32F4_SQ12_MASK GENMASK(29, 25) +#define STM32F4_SQ11_SHIFT 20 +#define STM32F4_SQ11_MASK GENMASK(24, 20) +#define STM32F4_SQ10_SHIFT 15 +#define STM32F4_SQ10_MASK GENMASK(19, 15) +#define STM32F4_SQ9_SHIFT 10 +#define STM32F4_SQ9_MASK GENMASK(14, 10) +#define STM32F4_SQ8_SHIFT 5 +#define STM32F4_SQ8_MASK GENMASK(9, 5) +#define STM32F4_SQ7_SHIFT 0 +#define STM32F4_SQ7_MASK GENMASK(4, 0) + +/* STM32F4_ADCX_SQR3 - bit fields */ +#define STM32F4_SQ6_SHIFT 25 +#define STM32F4_SQ6_MASK GENMASK(29, 25) +#define STM32F4_SQ5_SHIFT 20 +#define STM32F4_SQ5_MASK GENMASK(24, 20) +#define STM32F4_SQ4_SHIFT 15 +#define STM32F4_SQ4_MASK GENMASK(19, 15) +#define STM32F4_SQ3_SHIFT 10 +#define STM32F4_SQ3_MASK GENMASK(14, 10) +#define STM32F4_SQ2_SHIFT 5 +#define STM32F4_SQ2_MASK GENMASK(9, 5) +#define STM32F4_SQ1_SHIFT 0 +#define STM32F4_SQ1_MASK GENMASK(4, 0) + +/* STM32F4_ADCX_JSQR - bit fields */ +#define STM32F4_JL_SHIFT 20 +#define STM32F4_JL_MASK GENMASK(21, 20) +#define STM32F4_JSQ4_SHIFT 15 +#define STM32F4_JSQ4_MASK GENMASK(19, 15) +#define STM32F4_JSQ3_SHIFT 10 +#define STM32F4_JSQ3_MASK GENMASK(14, 10) +#define STM32F4_JSQ2_SHIFT 5 +#define STM32F4_JSQ2_MASK GENMASK(9, 5) +#define STM32F4_JSQ1_SHIFT 0 +#define STM32F4_JSQ1_MASK GENMASK(4, 0) + +/* STM32F4_ADC_CCR - bit fields */ +#define STM32F4_ADC_ADCPRE_SHIFT 16 +#define STM32F4_ADC_ADCPRE_MASK GENMASK(17, 16) + +/* + * stm32 ADC1, ADC2 & ADC3 are tightly coupled and may be used in multi mode + * Define here all inputs for all ADC instances + */ +static const struct stm32_adc_chan_spec stm32f4_adc1_channels[] = { + /* master ADC1 */ + { IIO_VOLTAGE, 0, "in0" }, + { IIO_VOLTAGE, 1, "in1" }, + { IIO_VOLTAGE, 2, "in2" }, + { IIO_VOLTAGE, 3, "in3" }, + { IIO_VOLTAGE, 4, "in4" }, + { IIO_VOLTAGE, 5, "in5" }, + { IIO_VOLTAGE, 6, "in6" }, + { IIO_VOLTAGE, 7, "in7" }, + { IIO_VOLTAGE, 8, "in8" }, + { IIO_VOLTAGE, 9, "in9" }, + { IIO_VOLTAGE, 10, "in10" }, + { IIO_VOLTAGE, 11, "in11" }, + { IIO_VOLTAGE, 12, "in12" }, + { IIO_VOLTAGE, 13, "in13" }, + { IIO_VOLTAGE, 14, "in14" }, + { IIO_VOLTAGE, 15, "in15" }, + /* internal analog sources available on input 16 to 18 */ + { IIO_VOLTAGE, 16, "in16" }, + { IIO_VOLTAGE, 17, "in17" }, + { IIO_VOLTAGE, 18, "in18" }, +}; + +static const struct stm32_adc_chan_spec stm32f4_adc23_channels[] = { + /* slave ADC2 / ADC3 */ + { IIO_VOLTAGE, 0, "in0" }, + { IIO_VOLTAGE, 1, "in1" }, + { IIO_VOLTAGE, 2, "in2" }, + { IIO_VOLTAGE, 3, "in3" }, + { IIO_VOLTAGE, 4, "in4" }, + { IIO_VOLTAGE, 5, "in5" }, + { IIO_VOLTAGE, 6, "in6" }, + { IIO_VOLTAGE, 7, "in7" }, + { IIO_VOLTAGE, 8, "in8" }, + { IIO_VOLTAGE, 9, "in9" }, + { IIO_VOLTAGE, 10, "in10" }, + { IIO_VOLTAGE, 11, "in11" }, + { IIO_VOLTAGE, 12, "in12" }, + { IIO_VOLTAGE, 13, "in13" }, + { IIO_VOLTAGE, 14, "in14" }, + { IIO_VOLTAGE, 15, "in15" }, +}; + +/* Triggers for regular channels */ +static const struct stm32_adc_trig_info stm32f4_adc_ext_triggers[] = { + { STM32_EXT0, "TIM1_CH1" }, + { STM32_EXT1, "TIM1_CH2" }, + { STM32_EXT2, "TIM1_CH3" }, + { STM32_EXT3, "TIM2_CH2" }, + { STM32_EXT4, "TIM2_CH3" }, + { STM32_EXT5, "TIM2_CH4" }, + { STM32_EXT6, "TIM2_TRGO" }, + { STM32_EXT7, "TIM3_CH1" }, + { STM32_EXT8, "TIM3_TRGO" }, + { STM32_EXT9, "TIM4_CH4" }, + { STM32_EXT10, "TIM5_CH1" }, + { STM32_EXT11, "TIM5_CH2" }, + { STM32_EXT12, "TIM5_CH3" }, + { STM32_EXT13, "TIM8_CH1" }, + { STM32_EXT14, "TIM8_TRGO" }, + { STM32_EXT15, "EXTI_11" }, + {}, +}; + +/* Triggers for injected channels */ +static const struct stm32_adc_trig_info stm32f4_adc_jext_triggers[] = { + { STM32_JEXT0, "TIM1_CH4" }, + { STM32_JEXT1, "TIM1_TRGO" }, + { STM32_JEXT2, "TIM2_CH1" }, + { STM32_JEXT3, "TIM2_TRGO" }, + { STM32_JEXT4, "TIM3_CH2" }, + { STM32_JEXT5, "TIM3_CH4" }, + { STM32_JEXT6, "TIM4_CH1" }, + { STM32_JEXT7, "TIM4_CH2" }, + { STM32_JEXT8, "TIM4_CH3" }, + { STM32_JEXT9, "TIM4_TRGO" }, + { STM32_JEXT10, "TIM5_CH4" }, + { STM32_JEXT11, "TIM5_TRGO" }, + { STM32_JEXT12, "TIM8_CH2" }, + { STM32_JEXT13, "TIM8_CH3" }, + { STM32_JEXT14, "TIM8_CH4" }, + { STM32_JEXT15, "EXTI_15" }, + {}, +}; + +static const struct stm32_adc_info stm32f4_adc_info[] = { + { + .name = "adc1-master", + .reg = 0x0, + .channels = stm32f4_adc1_channels, + .max_channels = ARRAY_SIZE(stm32f4_adc1_channels), + }, + { + .name = "adc2-slave", + .reg = 0x100, + .channels = stm32f4_adc23_channels, + .max_channels = ARRAY_SIZE(stm32f4_adc23_channels), + }, + { + .name = "adc3-slave", + .reg = 0x200, + .channels = stm32f4_adc23_channels, + .max_channels = ARRAY_SIZE(stm32f4_adc23_channels), + }, + {}, +}; + +/** + * stm32f4_sqr_regs - describe regular sequence registers + * - L: sequence len (register & bit field) + * - SQ1..SQ16: sequence entries (register & bit field) + */ +static const struct stm32_adc_regs stm32f4_sqr_regs[STM32_ADC_MAX_SQ + 1] = { + /* L: len bit field description to be kept as first element */ + { STM32F4_ADCX_SQR1, STM32F4_L_MASK, STM32F4_L_SHIFT }, + /* SQ1..SQ16 registers & bit fields */ + { STM32F4_ADCX_SQR3, STM32F4_SQ1_MASK, STM32F4_SQ1_SHIFT }, + { STM32F4_ADCX_SQR3, STM32F4_SQ2_MASK, STM32F4_SQ2_SHIFT }, + { STM32F4_ADCX_SQR3, STM32F4_SQ3_MASK, STM32F4_SQ3_SHIFT }, + { STM32F4_ADCX_SQR3, STM32F4_SQ4_MASK, STM32F4_SQ4_SHIFT }, + { STM32F4_ADCX_SQR3, STM32F4_SQ5_MASK, STM32F4_SQ5_SHIFT }, + { STM32F4_ADCX_SQR3, STM32F4_SQ6_MASK, STM32F4_SQ6_SHIFT }, + { STM32F4_ADCX_SQR2, STM32F4_SQ7_MASK, STM32F4_SQ7_SHIFT }, + { STM32F4_ADCX_SQR2, STM32F4_SQ8_MASK, STM32F4_SQ8_SHIFT }, + { STM32F4_ADCX_SQR2, STM32F4_SQ9_MASK, STM32F4_SQ9_SHIFT }, + { STM32F4_ADCX_SQR2, STM32F4_SQ10_MASK, STM32F4_SQ10_SHIFT }, + { STM32F4_ADCX_SQR2, STM32F4_SQ11_MASK, STM32F4_SQ11_SHIFT }, + { STM32F4_ADCX_SQR2, STM32F4_SQ12_MASK, STM32F4_SQ12_SHIFT }, + { STM32F4_ADCX_SQR1, STM32F4_SQ13_MASK, STM32F4_SQ13_SHIFT }, + { STM32F4_ADCX_SQR1, STM32F4_SQ14_MASK, STM32F4_SQ14_SHIFT }, + { STM32F4_ADCX_SQR1, STM32F4_SQ15_MASK, STM32F4_SQ15_SHIFT }, + { STM32F4_ADCX_SQR1, STM32F4_SQ16_MASK, STM32F4_SQ16_SHIFT }, +}; + +/** + * stm32f4_jsqr_reg - describe injected sequence register: + * - JL: injected sequence len + * - JSQ4..SQ1: sequence entries + * When JL == 3, ADC converts JSQ1, JSQ2, JSQ3, JSQ4 + * When JL == 2, ADC converts JSQ2, JSQ3, JSQ4 + * When JL == 1, ADC converts JSQ3, JSQ4 + * When JL == 0, ADC converts JSQ4 + */ +static const struct stm32_adc_regs stm32f4_jsqr_reg[STM32_ADC_MAX_JSQ + 1] = { + /* JL: len bit field description to be kept as first element */ + {STM32F4_ADCX_JSQR, STM32F4_JL_MASK, STM32F4_JL_SHIFT}, + /* JSQ4..JSQ1 registers & bit fields */ + {STM32F4_ADCX_JSQR, STM32F4_JSQ4_MASK, STM32F4_JSQ4_SHIFT}, + {STM32F4_ADCX_JSQR, STM32F4_JSQ3_MASK, STM32F4_JSQ3_SHIFT}, + {STM32F4_ADCX_JSQR, STM32F4_JSQ2_MASK, STM32F4_JSQ2_SHIFT}, + {STM32F4_ADCX_JSQR, STM32F4_JSQ1_MASK, STM32F4_JSQ1_SHIFT}, +}; + +static const struct stm32_adc_trig_reginfo stm32f4_adc_trig_reginfo = { + .reg = STM32F4_ADCX_CR2, + .exten_mask = STM32F4_EXTEN_MASK, + .exten_shift = STM32F4_EXTEN_SHIFT, + .extsel_mask = STM32F4_EXTSEL_MASK, + .extsel_shift = STM32F4_EXTSEL_SHIFT, +}; + +static const struct stm32_adc_trig_reginfo stm32f4_adc_jtrig_reginfo = { + .reg = STM32F4_ADCX_CR2, + .exten_mask = STM32F4_JEXTEN_MASK, + .exten_shift = STM32F4_JEXTEN_SHIFT, + .extsel_mask = STM32F4_JEXTSEL_MASK, + .extsel_shift = STM32F4_JEXTSEL_SHIFT, +}; + +static const struct stm32_adc_reginfo stm32f4_adc_reginfo = { + .isr = STM32F4_ADCX_SR, + .eoc = STM32F4_EOC, + .jeoc = STM32F4_JEOC, + .ier = STM32F4_ADCX_CR1, + .eocie = STM32F4_EOCIE, + .jeocie = STM32F4_JEOCIE, + .dr = STM32F4_ADCX_DR, + .jdr = { + STM32F4_ADCX_JDR1, + STM32F4_ADCX_JDR2, + STM32F4_ADCX_JDR3, + STM32F4_ADCX_JDR4, + }, + .sqr_regs = stm32f4_sqr_regs, + .jsqr_reg = stm32f4_jsqr_reg, + .trig_reginfo = &stm32f4_adc_trig_reginfo, + .jtrig_reginfo = &stm32f4_adc_jtrig_reginfo, +}; + +static bool stm32f4_adc_is_started(struct stm32_adc *adc) +{ + u32 val = stm32_adc_readl(adc, STM32F4_ADCX_CR2) & STM32F4_ADON; + + return !!val; +} + +static bool stm32f4_adc_regular_started(struct stm32_adc *adc) +{ + u32 val = stm32_adc_readl(adc, STM32F4_ADCX_SR) & STM32F4_STRT; + + return !!val; +} + +static bool stm32f4_adc_injected_started(struct stm32_adc *adc) +{ + u32 val = stm32_adc_readl(adc, STM32F4_ADCX_SR) & STM32F4_JSTRT; + + return !!val; +} + +/** + * stm32f4_adc_start_conv() - Start regular or injected conversions + * @adc: stm32 adc instance + * + * Start single conversions for regular or injected channels. + */ +static int stm32f4_adc_start_conv(struct stm32_adc *adc) +{ + u32 trig_msk, start_msk; + + dev_dbg(adc->common->dev, "%s %s\n", __func__, + adc->injected ? "injected" : "regular"); + + stm32_adc_set_bits(adc, STM32F4_ADCX_CR1, STM32F4_SCAN); + + if (!stm32f4_adc_is_started(adc)) { + stm32_adc_set_bits(adc, STM32F4_ADCX_CR2, + STM32F4_EOCS | STM32F4_ADON); + + /* Wait for Power-up time (tSTAB from datasheet) */ + usleep_range(2, 3); + } + + if (adc->injected) { + trig_msk = STM32F4_JEXTEN_MASK; + start_msk = STM32F4_JSWSTART; + } else { + trig_msk = STM32F4_EXTEN_MASK; + start_msk = STM32F4_SWSTART; + } + + /* Software start ? (e.g. trigger detection disabled ?) */ + if (!(stm32_adc_readl(adc, STM32F4_ADCX_CR2) & trig_msk)) + stm32_adc_set_bits(adc, STM32F4_ADCX_CR2, start_msk); + + return 0; +} + +static int stm32f4_adc_stop_conv(struct stm32_adc *adc) +{ + u32 val; + + dev_dbg(adc->common->dev, "%s %s\n", __func__, + adc->injected ? "injected" : "regular"); + + /* First disable trigger for either regular or injected channels */ + if (adc->injected) { + stm32_adc_clr_bits(adc, STM32F4_ADCX_CR2, STM32F4_JEXTEN_MASK); + stm32_adc_clr_bits(adc, STM32F4_ADCX_SR, STM32F4_JSTRT); + } else { + stm32_adc_clr_bits(adc, STM32F4_ADCX_CR2, STM32F4_EXTEN_MASK); + stm32_adc_clr_bits(adc, STM32F4_ADCX_SR, STM32F4_STRT); + } + + /* Disable adc when all triggered conversion have been disabled */ + val = stm32_adc_readl(adc, STM32F4_ADCX_CR2); + val &= STM32F4_EXTEN_MASK | STM32F4_JEXTEN_MASK; + if (!val) { + stm32_adc_clr_bits(adc, STM32F4_ADCX_CR1, STM32F4_SCAN); + stm32_adc_clr_bits(adc, STM32F4_ADCX_CR2, STM32F4_ADON); + } + + return 0; +} + +/* ADC internal common clock prescaler division ratios */ +static int stm32f4_pclk_div[] = {2, 4, 6, 8}; + +/** + * stm32f4_adc_clk_sel() - Select ADC common clock prescaler + * @adc: stm32 adc instance + * Select clock prescaler used for analog conversions. + */ +static int stm32f4_adc_clk_sel(struct stm32_adc *adc) +{ + struct stm32_adc_common *common = adc->common; + unsigned long rate; + u32 val; + int i; + + /* Common prescaler is set only once, when 1st ADC instance starts */ + list_for_each_entry(adc, &common->adc_list, adc_list) + if (stm32f4_adc_is_started(adc)) + return 0; + + rate = clk_get_rate(common->aclk); + for (i = 0; i < ARRAY_SIZE(stm32f4_pclk_div); i++) { + if ((rate / stm32f4_pclk_div[i]) <= + common->data->max_clock_rate) + break; + } + if (i >= ARRAY_SIZE(stm32f4_pclk_div)) + return -EINVAL; + + val = stm32_adc_common_readl(common, STM32F4_ADC_CCR); + val &= ~STM32F4_ADC_ADCPRE_MASK; + val |= i << STM32F4_ADC_ADCPRE_SHIFT; + stm32_adc_common_writel(common, STM32F4_ADC_CCR, val); + + dev_dbg(common->dev, "Using analog clock source at %ld kHz\n", + rate / (stm32f4_pclk_div[i] * 1000)); + + return 0; +} + +static const struct stm32_adc_ops stm32f4_adc_ops = { + .adc_info = stm32f4_adc_info, + .ext_triggers = stm32f4_adc_ext_triggers, + .jext_triggers = stm32f4_adc_jext_triggers, + .adc_reginfo = &stm32f4_adc_reginfo, + .highres = 12, + .max_clock_rate = 36000000, + .clk_sel = stm32f4_adc_clk_sel, + .start_conv = stm32f4_adc_start_conv, + .stop_conv = stm32f4_adc_stop_conv, + .is_started = stm32f4_adc_is_started, + .regular_started = stm32f4_adc_regular_started, + .injected_started = stm32f4_adc_injected_started, +}; + +static const struct of_device_id stm32f4_adc_of_match[] = { + { .compatible = "st,stm32f4-adc", .data = (void *)&stm32f4_adc_ops}, + {}, +}; +MODULE_DEVICE_TABLE(of, stm32f4_adc_of_match); + +static struct platform_driver stm32f4_adc_driver = { + .probe = stm32_adc_probe, + .remove = stm32_adc_remove, + .driver = { + .name = "stm32f4-adc", + .of_match_table = stm32f4_adc_of_match, + }, +}; + +module_platform_driver(stm32f4_adc_driver); + +MODULE_AUTHOR("Fabrice Gasnier "); +MODULE_DESCRIPTION("STMicroelectronics STM32F4 ADC driver"); +MODULE_LICENSE("GPL v2"); -- 1.9.1