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Release 4.7 drivers/iio/adc/ti_am335x_adc.c

Directory: drivers/iio/adc
/*
 * TI ADC MFD driver
 *
 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
 *
 * 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 version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/iio/iio.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/iio/machine.h>
#include <linux/iio/driver.h>

#include <linux/mfd/ti_am335x_tscadc.h>
#include <linux/iio/buffer.h>
#include <linux/iio/kfifo_buf.h>


struct tiadc_device {
	
struct ti_tscadc_dev *mfd_tscadc;
	
int channels;
	
u8 channel_line[8];
	
u8 channel_step[8];
	
int buffer_en_ch_steps;
	
u16 data[8];
	


u32 open_delay[8], sample_delay[8], step_avg[8];
};


static unsigned int tiadc_readl(struct tiadc_device *adc, unsigned int reg) { return readl(adc->mfd_tscadc->tscadc_base + reg); }

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static void tiadc_writel(struct tiadc_device *adc, unsigned int reg, unsigned int val) { writel(val, adc->mfd_tscadc->tscadc_base + reg); }

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static u32 get_adc_step_mask(struct tiadc_device *adc_dev) { u32 step_en; step_en = ((1 << adc_dev->channels) - 1); step_en <<= TOTAL_STEPS - adc_dev->channels + 1; return step_en; }

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Total41100.00%2100.00%


static u32 get_adc_chan_step_mask(struct tiadc_device *adc_dev, struct iio_chan_spec const *chan) { int i; for (i = 0; i < ARRAY_SIZE(adc_dev->channel_step); i++) { if (chan->channel == adc_dev->channel_line[i]) { u32 step; step = adc_dev->channel_step[i]; /* +1 for the charger */ return 1 << (step + 1); } } WARN_ON(1); return 0; }

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static u32 get_adc_step_bit(struct tiadc_device *adc_dev, int chan) { return 1 << adc_dev->channel_step[chan]; }

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static void tiadc_step_config(struct iio_dev *indio_dev) { struct tiadc_device *adc_dev = iio_priv(indio_dev); struct device *dev = adc_dev->mfd_tscadc->dev; unsigned int stepconfig; int i, steps = 0; /* * There are 16 configurable steps and 8 analog input * lines available which are shared between Touchscreen and ADC. * * Steps forwards i.e. from 0 towards 16 are used by ADC * depending on number of input lines needed. * Channel would represent which analog input * needs to be given to ADC to digitalize data. */ for (i = 0; i < adc_dev->channels; i++) { int chan; chan = adc_dev->channel_line[i]; if (adc_dev->step_avg[i] > STEPCONFIG_AVG_16) { dev_warn(dev, "chan %d step_avg truncating to %d\n", chan, STEPCONFIG_AVG_16); adc_dev->step_avg[i] = STEPCONFIG_AVG_16; } if (adc_dev->step_avg[i]) stepconfig = STEPCONFIG_AVG(ffs(adc_dev->step_avg[i]) - 1) | STEPCONFIG_FIFO1; else stepconfig = STEPCONFIG_FIFO1; if (iio_buffer_enabled(indio_dev)) stepconfig |= STEPCONFIG_MODE_SWCNT; tiadc_writel(adc_dev, REG_STEPCONFIG(steps), stepconfig | STEPCONFIG_INP(chan)); if (adc_dev->open_delay[i] > STEPDELAY_OPEN_MASK) { dev_warn(dev, "chan %d open delay truncating to 0x3FFFF\n", chan); adc_dev->open_delay[i] = STEPDELAY_OPEN_MASK; } if (adc_dev->sample_delay[i] > 0xFF) { dev_warn(dev, "chan %d sample delay truncating to 0xFF\n", chan); adc_dev->sample_delay[i] = 0xFF; } tiadc_writel(adc_dev, REG_STEPDELAY(steps), STEPDELAY_OPEN(adc_dev->open_delay[i]) | STEPDELAY_SAMPLE(adc_dev->sample_delay[i])); adc_dev->channel_step[i] = steps; steps++; } }

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brad griffisbrad griffis31.11%133.33%
Total271100.00%3100.00%


static irqreturn_t tiadc_irq_h(int irq, void *private) { struct iio_dev *indio_dev = private; struct tiadc_device *adc_dev = iio_priv(indio_dev); unsigned int status, config; status = tiadc_readl(adc_dev, REG_IRQSTATUS); /* * ADC and touchscreen share the IRQ line. * FIFO0 interrupts are used by TSC. Handle FIFO1 IRQs here only */ if (status & IRQENB_FIFO1OVRRUN) { /* FIFO Overrun. Clear flag. Disable/Enable ADC to recover */ config = tiadc_readl(adc_dev, REG_CTRL); config &= ~(CNTRLREG_TSCSSENB); tiadc_writel(adc_dev, REG_CTRL, config); tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW | IRQENB_FIFO1THRES); tiadc_writel(adc_dev, REG_CTRL, (config | CNTRLREG_TSCSSENB)); return IRQ_HANDLED; } else if (status & IRQENB_FIFO1THRES) { /* Disable irq and wake worker thread */ tiadc_writel(adc_dev, REG_IRQCLR, IRQENB_FIFO1THRES); return IRQ_WAKE_THREAD; } return IRQ_NONE; }

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static irqreturn_t tiadc_worker_h(int irq, void *private) { struct iio_dev *indio_dev = private; struct tiadc_device *adc_dev = iio_priv(indio_dev); int i, k, fifo1count, read; u16 *data = adc_dev->data; fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT); for (k = 0; k < fifo1count; k = k + i) { for (i = 0; i < (indio_dev->scan_bytes)/2; i++) { read = tiadc_readl(adc_dev, REG_FIFO1); data[i] = read & FIFOREAD_DATA_MASK; } iio_push_to_buffers(indio_dev, (u8 *) data); } tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1THRES); tiadc_writel(adc_dev, REG_IRQENABLE, IRQENB_FIFO1THRES); return IRQ_HANDLED; }

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static int tiadc_buffer_preenable(struct iio_dev *indio_dev) { struct tiadc_device *adc_dev = iio_priv(indio_dev); int i, fifo1count, read; tiadc_writel(adc_dev, REG_IRQCLR, (IRQENB_FIFO1THRES | IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW)); /* Flush FIFO. Needed in corner cases in simultaneous tsc/adc use */ fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT); for (i = 0; i < fifo1count; i++) read = tiadc_readl(adc_dev, REG_FIFO1); return 0; }

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Total78100.00%2100.00%


static int tiadc_buffer_postenable(struct iio_dev *indio_dev) { struct tiadc_device *adc_dev = iio_priv(indio_dev); unsigned int enb = 0; u8 bit; tiadc_step_config(indio_dev); for_each_set_bit(bit, indio_dev->active_scan_mask, adc_dev->channels) enb |= (get_adc_step_bit(adc_dev, bit) << 1); adc_dev->buffer_en_ch_steps = enb; am335x_tsc_se_set_cache(adc_dev->mfd_tscadc, enb); tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1THRES | IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW); tiadc_writel(adc_dev, REG_IRQENABLE, IRQENB_FIFO1THRES | IRQENB_FIFO1OVRRUN); return 0; }

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zubair lutfullahzubair lutfullah9697.96%133.33%
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sebastian andrzej siewiorsebastian andrzej siewior11.02%133.33%
Total98100.00%3100.00%


static int tiadc_buffer_predisable(struct iio_dev *indio_dev) { struct tiadc_device *adc_dev = iio_priv(indio_dev); int fifo1count, i, read; tiadc_writel(adc_dev, REG_IRQCLR, (IRQENB_FIFO1THRES | IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW)); am335x_tsc_se_clr(adc_dev->mfd_tscadc, adc_dev->buffer_en_ch_steps); adc_dev->buffer_en_ch_steps = 0; /* Flush FIFO of leftover data in the time it takes to disable adc */ fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT); for (i = 0; i < fifo1count; i++) read = tiadc_readl(adc_dev, REG_FIFO1); return 0; }

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Total95100.00%2100.00%


static int tiadc_buffer_postdisable(struct iio_dev *indio_dev) { tiadc_step_config(indio_dev); return 0; }

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static const struct iio_buffer_setup_ops tiadc_buffer_setup_ops = { .preenable = &tiadc_buffer_preenable, .postenable = &tiadc_buffer_postenable, .predisable = &tiadc_buffer_predisable, .postdisable = &tiadc_buffer_postdisable, };
static int tiadc_iio_buffered_hardware_setup(struct iio_dev *indio_dev, irqreturn_t (*pollfunc_bh)(int irq, void *p), irqreturn_t (*pollfunc_th)(int irq, void *p), int irq, unsigned long flags, const struct iio_buffer_setup_ops *setup_ops) { struct iio_buffer *buffer; int ret; buffer = iio_kfifo_allocate(); if (!buffer) return -ENOMEM; iio_device_attach_buffer(indio_dev, buffer); ret = request_threaded_irq(irq, pollfunc_th, pollfunc_bh, flags, indio_dev->name, indio_dev); if (ret) goto error_kfifo_free; indio_dev->setup_ops = setup_ops; indio_dev->modes |= INDIO_BUFFER_SOFTWARE; return 0; error_kfifo_free: iio_kfifo_free(indio_dev->buffer); return ret; }

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zubair lutfullahzubair lutfullah11082.09%233.33%
lars-peter clausenlars-peter clausen128.96%116.67%
rachna patilrachna patil107.46%116.67%
jonathan cameronjonathan cameron10.75%116.67%
karol wronakarol wrona10.75%116.67%
Total134100.00%6100.00%


static void tiadc_iio_buffered_hardware_remove(struct iio_dev *indio_dev) { struct tiadc_device *adc_dev = iio_priv(indio_dev); free_irq(adc_dev->mfd_tscadc->irq, indio_dev); iio_kfifo_free(indio_dev->buffer); }

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zubair lutfullahzubair lutfullah2256.41%133.33%
rachna patilrachna patil1538.46%133.33%
sebastian andrzej siewiorsebastian andrzej siewior25.13%133.33%
Total39100.00%3100.00%

static const char * const chan_name_ain[] = { "AIN0", "AIN1", "AIN2", "AIN3", "AIN4", "AIN5", "AIN6", "AIN7", };
static int tiadc_channel_init(struct iio_dev *indio_dev, int channels) { struct tiadc_device *adc_dev = iio_priv(indio_dev); struct iio_chan_spec *chan_array; struct iio_chan_spec *chan; int i; indio_dev->num_channels = channels; chan_array = kcalloc(channels, sizeof(struct iio_chan_spec), GFP_KERNEL); if (chan_array == NULL) return -ENOMEM; chan = chan_array; for (i = 0; i < channels; i++, chan++) { chan->type = IIO_VOLTAGE; chan->indexed = 1; chan->channel = adc_dev->channel_line[i]; chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); chan->datasheet_name = chan_name_ain[chan->channel]; chan->scan_index = i; chan->scan_type.sign = 'u'; chan->scan_type.realbits = 12; chan->scan_type.storagebits = 16; } indio_dev->channels = chan_array; return 0; }

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rachna patilrachna patil9655.81%116.67%
pantelis antonioupantelis antoniou5632.56%116.67%
sebastian andrzej siewiorsebastian andrzej siewior84.65%116.67%
zubair lutfullahzubair lutfullah74.07%233.33%
jonathan cameronjonathan cameron52.91%116.67%
Total172100.00%6100.00%


static void tiadc_channels_remove(struct iio_dev *indio_dev) { kfree(indio_dev->channels); }

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static int tiadc_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct tiadc_device *adc_dev = iio_priv(indio_dev); int i, map_val; unsigned int fifo1count, read, stepid; bool found = false; u32 step_en; unsigned long timeout; if (iio_buffer_enabled(indio_dev)) return -EBUSY; step_en = get_adc_chan_step_mask(adc_dev, chan); if (!step_en) return -EINVAL; fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT); while (fifo1count--) tiadc_readl(adc_dev, REG_FIFO1); am335x_tsc_se_set_once(adc_dev->mfd_tscadc, step_en); timeout = jiffies + usecs_to_jiffies (IDLE_TIMEOUT * adc_dev->channels); /* Wait for Fifo threshold interrupt */ while (1) { fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT); if (fifo1count) break; if (time_after(jiffies, timeout)) { am335x_tsc_se_adc_done(adc_dev->mfd_tscadc); return -EAGAIN; } } map_val = adc_dev->channel_step[chan->scan_index]; /* * We check the complete FIFO. We programmed just one entry but in case * something went wrong we left empty handed (-EAGAIN previously) and * then the value apeared somehow in the FIFO we would have two entries. * Therefore we read every item and keep only the latest version of the * requested channel. */ for (i = 0; i < fifo1count; i++) { read = tiadc_readl(adc_dev, REG_FIFO1); stepid = read & FIFOREAD_CHNLID_MASK; stepid = stepid >> 0x10; if (stepid == map_val) { read = read & FIFOREAD_DATA_MASK; found = true; *val = (u16) read; } } am335x_tsc_se_adc_done(adc_dev->mfd_tscadc); if (found == false) return -EBUSY; return IIO_VAL_INT; }

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rachna patilrachna patil15155.51%222.22%
sebastian andrzej siewiorsebastian andrzej siewior10137.13%444.44%
zubair lutfullahzubair lutfullah145.15%222.22%
jan kardelljan kardell62.21%111.11%
Total272100.00%9100.00%

static const struct iio_info tiadc_info = { .read_raw = &tiadc_read_raw, .driver_module = THIS_MODULE, };
static int tiadc_parse_dt(struct platform_device *pdev, struct tiadc_device *adc_dev) { struct device_node *node = pdev->dev.of_node; struct property *prop; const __be32 *cur; int channels = 0; u32 val; of_property_for_each_u32(node, "ti,adc-channels", prop, cur, val) { adc_dev->channel_line[channels] = val; /* Set Default values for optional DT parameters */ adc_dev->open_delay[channels] = STEPCONFIG_OPENDLY; adc_dev->sample_delay[channels] = STEPCONFIG_SAMPLEDLY; adc_dev->step_avg[channels] = 16; channels++; } of_property_read_u32_array(node, "ti,chan-step-avg", adc_dev->step_avg, channels); of_property_read_u32_array(node, "ti,chan-step-opendelay", adc_dev->open_delay, channels); of_property_read_u32_array(node, "ti,chan-step-sampledelay", adc_dev->sample_delay, channels); adc_dev->channels = channels; return 0; }

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sebastian andrzej siewiorsebastian andrzej siewior149.52%120.00%
Total147100.00%5100.00%


static int tiadc_probe(struct platform_device *pdev) { struct iio_dev *indio_dev; struct tiadc_device *adc_dev; struct device_node *node = pdev->dev.of_node; int err; if (!node) { dev_err(&pdev->dev, "Could not find valid DT data.\n"); return -EINVAL; } indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct tiadc_device)); if (indio_dev == NULL) { dev_err(&pdev->dev, "failed to allocate iio device\n"); return -ENOMEM; } adc_dev = iio_priv(indio_dev); adc_dev->mfd_tscadc = ti_tscadc_dev_get(pdev); tiadc_parse_dt(pdev, adc_dev); indio_dev->dev.parent = &pdev->dev; indio_dev->name = dev_name(&pdev->dev); indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->info = &tiadc_info; tiadc_step_config(indio_dev); tiadc_writel(adc_dev, REG_FIFO1THR, FIFO1_THRESHOLD); err = tiadc_channel_init(indio_dev, adc_dev->channels); if (err < 0) return err; err = tiadc_iio_buffered_hardware_setup(indio_dev, &tiadc_worker_h, &tiadc_irq_h, adc_dev->mfd_tscadc->irq, IRQF_SHARED, &tiadc_buffer_setup_ops); if (err) goto err_free_channels; err = iio_device_register(indio_dev); if (err) goto err_buffer_unregister; platform_set_drvdata(pdev, indio_dev); return 0; err_buffer_unregister: tiadc_iio_buffered_hardware_remove(indio_dev); err_free_channels: tiadc_channels_remove(indio_dev); return err; }

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rachna patilrachna patil16162.16%228.57%
zubair lutfullahzubair lutfullah4818.53%114.29%
vignesh rvignesh r3613.90%114.29%
sachin kamatsachin kamat114.25%114.29%
sebastian andrzej siewiorsebastian andrzej siewior31.16%228.57%
Total259100.00%7100.00%


static int tiadc_remove(struct platform_device *pdev) { struct iio_dev *indio_dev = platform_get_drvdata(pdev); struct tiadc_device *adc_dev = iio_priv(indio_dev); u32 step_en; iio_device_unregister(indio_dev); tiadc_iio_buffered_hardware_remove(indio_dev); tiadc_channels_remove(indio_dev); step_en = get_adc_step_mask(adc_dev); am335x_tsc_se_clr(adc_dev->mfd_tscadc, step_en); return 0; }

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rachna patilrachna patil6392.65%266.67%
zubair lutfullahzubair lutfullah57.35%133.33%
Total68100.00%3100.00%

#ifdef CONFIG_PM
static int tiadc_suspend(struct device *dev) { struct iio_dev *indio_dev = dev_get_drvdata(dev); struct tiadc_device *adc_dev = iio_priv(indio_dev); struct ti_tscadc_dev *tscadc_dev; unsigned int idle; tscadc_dev = ti_tscadc_dev_get(to_platform_device(dev)); if (!device_may_wakeup(tscadc_dev->dev)) { idle = tiadc_readl(adc_dev, REG_CTRL); idle &= ~(CNTRLREG_TSCSSENB); tiadc_writel(adc_dev, REG_CTRL, (idle | CNTRLREG_POWERDOWN)); } return 0; }

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sebastian andrzej siewiorsebastian andrzej siewior1010.64%150.00%
Total94100.00%2100.00%


static int tiadc_resume(struct device *dev) { struct iio_dev *indio_dev = dev_get_drvdata(dev); struct tiadc_device *adc_dev = iio_priv(indio_dev); unsigned int restore; /* Make sure ADC is powered up */ restore = tiadc_readl(adc_dev, REG_CTRL); restore &= ~(CNTRLREG_POWERDOWN); tiadc_writel(adc_dev, REG_CTRL, restore); tiadc_step_config(indio_dev); am335x_tsc_se_set_cache(adc_dev->mfd_tscadc, adc_dev->buffer_en_ch_steps); return 0; }

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rachna patilrachna patil6885.00%125.00%
sebastian andrzej siewiorsebastian andrzej siewior1113.75%250.00%
zubair lutfullahzubair lutfullah11.25%125.00%
Total80100.00%4100.00%

static const struct dev_pm_ops tiadc_pm_ops = { .suspend = tiadc_suspend, .resume = tiadc_resume, }; #define TIADC_PM_OPS (&tiadc_pm_ops) #else #define TIADC_PM_OPS NULL #endif static const struct of_device_id ti_adc_dt_ids[] = { { .compatible = "ti,am3359-adc", }, { } }; MODULE_DEVICE_TABLE(of, ti_adc_dt_ids); static struct platform_driver tiadc_driver = { .driver = { .name = "TI-am335x-adc", .pm = TIADC_PM_OPS, .of_match_table = ti_adc_dt_ids, }, .probe = tiadc_probe, .remove = tiadc_remove, }; module_platform_driver(tiadc_driver); MODULE_DESCRIPTION("TI ADC controller driver"); MODULE_AUTHOR("Rachna Patil <rachna@ti.com>"); MODULE_LICENSE("GPL");

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zubair lutfullahzubair lutfullah97337.12%310.71%
rachna patilrachna patil93135.52%414.29%
vignesh rvignesh r32912.55%27.14%
sebastian andrzej siewiorsebastian andrzej siewior2549.69%828.57%
pantelis antonioupantelis antoniou883.36%13.57%
lars-peter clausenlars-peter clausen130.50%27.14%
sachin kamatsachin kamat110.42%13.57%
jonathan cameronjonathan cameron60.23%27.14%
jan kardelljan kardell60.23%13.57%
wei yongjunwei yongjun50.19%13.57%
brad griffisbrad griffis30.11%13.57%
karol wronakarol wrona10.04%13.57%
octavian purdilaoctavian purdila10.04%13.57%
Total2621100.00%28100.00%
Directory: drivers/iio/adc
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