cregit-Linux how code gets into the kernel

Release 4.11 drivers/staging/iio/adc/lpc32xx_adc.c

/*
 *  lpc32xx_adc.c - Support for ADC in LPC32XX
 *
 *  3-channel, 10-bit ADC
 *
 *  Copyright (C) 2011, 2012 Roland Stigge <stigge@antcom.de>
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/completion.h>
#include <linux/of.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

/*
 * LPC32XX registers definitions
 */

#define LPC32XX_ADC_SELECT(x)	((x) + 0x04)

#define LPC32XX_ADC_CTRL(x)	((x) + 0x08)

#define LPC32XX_ADC_VALUE(x)	((x) + 0x48)

/* Bit definitions for LPC32XX_ADC_SELECT: */

#define AD_REFm         0x00000200 
/* constant, always write this value! */

#define AD_REFp		0x00000080 
/* constant, always write this value! */

#define AD_IN		0x00000010 
/* multiple of this is the */
				   /* channel number: 0, 1, 2 */

#define AD_INTERNAL	0x00000004 
/* constant, always write this value! */

/* Bit definitions for LPC32XX_ADC_CTRL: */

#define AD_STROBE	0x00000002

#define AD_PDN_CTRL	0x00000004

/* Bit definitions for LPC32XX_ADC_VALUE: */

#define ADC_VALUE_MASK	0x000003FF


#define MOD_NAME "lpc32xx-adc"


struct lpc32xx_adc_info {
	
void __iomem *adc_base;
	
struct clk *clk;
	
struct completion completion;

	
u32 value;
};


static int lpc32xx_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct lpc32xx_adc_info *info = iio_priv(indio_dev); if (mask == IIO_CHAN_INFO_RAW) { mutex_lock(&indio_dev->mlock); clk_prepare_enable(info->clk); /* Measurement setup */ __raw_writel(AD_INTERNAL | (chan->address) | AD_REFp | AD_REFm, LPC32XX_ADC_SELECT(info->adc_base)); /* Trigger conversion */ __raw_writel(AD_PDN_CTRL | AD_STROBE, LPC32XX_ADC_CTRL(info->adc_base)); wait_for_completion(&info->completion); /* set by ISR */ clk_disable_unprepare(info->clk); *val = info->value; mutex_unlock(&indio_dev->mlock); return IIO_VAL_INT; } return -EINVAL; }

Contributors

PersonTokensPropCommitsCommitProp
Roland Stigge13497.81%133.33%
Vladimir Zapolskiy21.46%133.33%
Jonathan Cameron10.73%133.33%
Total137100.00%3100.00%

static const struct iio_info lpc32xx_adc_iio_info = { .read_raw = &lpc32xx_read_raw, .driver_module = THIS_MODULE, }; #define LPC32XX_ADC_CHANNEL(_index) { \ .type = IIO_VOLTAGE, \ .indexed = 1, \ .channel = _index, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .address = AD_IN * _index, \ .scan_index = _index, \ } static const struct iio_chan_spec lpc32xx_adc_iio_channels[] = { LPC32XX_ADC_CHANNEL(0), LPC32XX_ADC_CHANNEL(1), LPC32XX_ADC_CHANNEL(2), };
static irqreturn_t lpc32xx_adc_isr(int irq, void *dev_id) { struct lpc32xx_adc_info *info = dev_id; /* Read value and clear irq */ info->value = __raw_readl(LPC32XX_ADC_VALUE(info->adc_base)) & ADC_VALUE_MASK; complete(&info->completion); return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Roland Stigge48100.00%1100.00%
Total48100.00%1100.00%


static int lpc32xx_adc_probe(struct platform_device *pdev) { struct lpc32xx_adc_info *info = NULL; struct resource *res; int retval = -ENODEV; struct iio_dev *iodev = NULL; int irq; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(&pdev->dev, "failed to get platform I/O memory\n"); return -ENXIO; } iodev = devm_iio_device_alloc(&pdev->dev, sizeof(*info)); if (!iodev) return -ENOMEM; info = iio_priv(iodev); info->adc_base = devm_ioremap(&pdev->dev, res->start, resource_size(res)); if (!info->adc_base) { dev_err(&pdev->dev, "failed mapping memory\n"); return -EBUSY; } info->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(info->clk)) { dev_err(&pdev->dev, "failed getting clock\n"); return PTR_ERR(info->clk); } irq = platform_get_irq(pdev, 0); if (irq <= 0) { dev_err(&pdev->dev, "failed getting interrupt resource\n"); return -ENXIO; } retval = devm_request_irq(&pdev->dev, irq, lpc32xx_adc_isr, 0, MOD_NAME, info); if (retval < 0) { dev_err(&pdev->dev, "failed requesting interrupt\n"); return retval; } platform_set_drvdata(pdev, iodev); init_completion(&info->completion); iodev->name = MOD_NAME; iodev->dev.parent = &pdev->dev; iodev->info = &lpc32xx_adc_iio_info; iodev->modes = INDIO_DIRECT_MODE; iodev->channels = lpc32xx_adc_iio_channels; iodev->num_channels = ARRAY_SIZE(lpc32xx_adc_iio_channels); retval = devm_iio_device_register(&pdev->dev, iodev); if (retval) return retval; dev_info(&pdev->dev, "LPC32XX ADC driver loaded, IRQ %d\n", irq); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Roland Stigge30184.55%116.67%
Sachin Kamat4913.76%233.33%
Lars-Peter Clausen41.12%233.33%
Peng Fan20.56%116.67%
Total356100.00%6100.00%

#ifdef CONFIG_OF static const struct of_device_id lpc32xx_adc_match[] = { { .compatible = "nxp,lpc3220-adc" }, {}, }; MODULE_DEVICE_TABLE(of, lpc32xx_adc_match); #endif static struct platform_driver lpc32xx_adc_driver = { .probe = lpc32xx_adc_probe, .driver = { .name = MOD_NAME, .of_match_table = of_match_ptr(lpc32xx_adc_match), }, }; module_platform_driver(lpc32xx_adc_driver); MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>"); MODULE_DESCRIPTION("LPC32XX ADC driver"); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
Roland Stigge73392.20%216.67%
Sachin Kamat496.16%216.67%
Lars-Peter Clausen50.63%325.00%
Jonathan Cameron40.50%325.00%
Vladimir Zapolskiy20.25%18.33%
Peng Fan20.25%18.33%
Total795100.00%12100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.