On 09/26/2012 06:20 AM, Patil, Rachna wrote: > This patch adds support for TI's ADC driver. > This is a multifunctional device. > Analog input lines are provided on which > voltage measurements can be carried out. > You can have upto 8 input lines. > > Signed-off-by: Patil, Rachna <rac...@ti.com> Acked-by: Jonathan Cameron <ji...@kernel.org>
Note I cannot build test and it won't apply to staging-next without some merge fixes. I wonder if this driver is a case for a small tree that gets pulled into input/iio/mfd in the next cycle. It's a fiddly merge at best right now as there have been changes that effect it in all 3 subsystems earlier in this cycle (iio ones may just be fuzz, I haven't gotten to a state to check it hasn't hit anything else!) > --- > Changes in v2: > Addressed review comments from Matthias Kaehlcke > > Changes in v3: > Addressed review comments from Jonathan Cameron. > Added comments, new line appropriately. > > Changes in v4: > Removed extra comments and variables. > rename idev to indio_dev throughout the driver. > Renamed structs for better readability. > > drivers/iio/adc/Kconfig | 7 + > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/ti_am335x_adc.c | 216 > +++++++++++++++++++++++++++ > drivers/mfd/ti_am335x_tscadc.c | 18 ++- > include/linux/mfd/ti_am335x_tscadc.h | 9 +- > include/linux/platform_data/ti_am335x_adc.h | 14 ++ > 6 files changed, 263 insertions(+), 2 deletions(-) > create mode 100644 drivers/iio/adc/ti_am335x_adc.c > create mode 100644 include/linux/platform_data/ti_am335x_adc.h > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 8a78b4f..59db45f 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -22,4 +22,11 @@ config AT91_ADC > help > Say yes here to build support for Atmel AT91 ADC. > > +config TI_AM335X_ADC > + tristate "TI's ADC driver" > + depends on ARCH_OMAP2PLUS > + help > + Say yes here to build support for Texas Instruments ADC > + driver which is also a MFD client. > + > endmenu > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index 52eec25..e716588 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -4,3 +4,4 @@ > > obj-$(CONFIG_AD7266) += ad7266.o > obj-$(CONFIG_AT91_ADC) += at91_adc.o > +obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o > diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c > new file mode 100644 > index 0000000..9e1b3ac > --- /dev/null > +++ b/drivers/iio/adc/ti_am335x_adc.c > @@ -0,0 +1,216 @@ > +/* > + * 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/init.h> > +#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/mfd/ti_am335x_tscadc.h> > +#include <linux/platform_data/ti_am335x_adc.h> > + > +struct tiadc_device { > + struct ti_tscadc_dev *mfd_tscadc; > + int channels; > +}; > + > +static unsigned int adc_readl(struct tiadc_device *adc, unsigned int reg) > +{ > + return readl(adc->mfd_tscadc->tscadc_base + reg); > +} > + > +static void adc_writel(struct tiadc_device *adc, unsigned int reg, > + unsigned int val) > +{ > + writel(val, adc->mfd_tscadc->tscadc_base + reg); > +} > + > +static void adc_step_config(struct tiadc_device *adc_dev) > +{ > + unsigned int stepconfig; > + int i, channels = 0, steps; > + > + /* > + * There are 16 configurable steps and 8 analog input > + * lines available which are shared between Touchscreen and ADC. > + * > + * Steps backwards i.e. from 16 towards 0 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. > + */ > + > + steps = TOTAL_STEPS - adc_dev->channels; > + channels = TOTAL_CHANNELS - adc_dev->channels; > + > + stepconfig = STEPCONFIG_AVG_16 | STEPCONFIG_FIFO1; > + > + for (i = (steps + 1); i <= TOTAL_STEPS; i++) { > + adc_writel(adc_dev, REG_STEPCONFIG(i), > + stepconfig | STEPCONFIG_INP(channels)); > + adc_writel(adc_dev, REG_STEPDELAY(i), > + STEPCONFIG_OPENDLY); > + channels++; > + } > + adc_writel(adc_dev, REG_SE, STPENB_STEPENB); > +} > + > +static int tiadc_channel_init(struct iio_dev *indio_dev, int channels) > +{ > + struct iio_chan_spec *chan_array; > + int i; > + > + indio_dev->num_channels = channels; > + chan_array = kcalloc(indio_dev->num_channels, > + sizeof(struct iio_chan_spec), GFP_KERNEL); > + > + if (chan_array == NULL) > + return -ENOMEM; > + > + for (i = 0; i < (indio_dev->num_channels); i++) { > + struct iio_chan_spec *chan = chan_array + i; > + chan->type = IIO_VOLTAGE; > + chan->indexed = 1; > + chan->channel = i; > + chan->info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT; > + } > + > + indio_dev->channels = chan_array; > + > + return indio_dev->num_channels; > +} > + > +static void tiadc_channels_remove(struct iio_dev *indio_dev) > +{ > + kfree(indio_dev->channels); > +} > + > +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; > + unsigned int fifo1count, readx1; > + > + /* > + * When the sub-system is first enabled, > + * the sequencer will always start with the > + * lowest step (1) and continue until step (16). > + * For ex: If we have enabled 4 ADC channels and > + * currently use only 1 out of them, the > + * sequencer still configures all the 4 steps, > + * leading to 3 unwanted data. > + * Hence we need to flush out this data. > + */ > + > + fifo1count = adc_readl(adc_dev, REG_FIFO1CNT); > + for (i = 0; i < fifo1count; i++) { > + readx1 = adc_readl(adc_dev, REG_FIFO1); > + if (i == chan->channel) > + *val = readx1 & 0xfff; > + } > + adc_writel(adc_dev, REG_SE, STPENB_STEPENB); > + > + return IIO_VAL_INT; > +} > + > +static const struct iio_info tiadc_info = { > + .read_raw = &tiadc_read_raw, > +}; > + > +static int __devinit tiadc_probe(struct platform_device *pdev) > +{ > + struct iio_dev *indio_dev; > + struct tiadc_device *adc_dev; > + struct ti_tscadc_dev *tscadc_dev = pdev->dev.platform_data; > + struct mfd_tscadc_board *pdata; > + int err; > + > + pdata = tscadc_dev->dev->platform_data; > + if (!pdata || !pdata->adc_init) { > + dev_err(&pdev->dev, "Could not find platform data\n"); > + return -EINVAL; > + } > + > + indio_dev = iio_device_alloc(sizeof(struct tiadc_device)); > + if (indio_dev == NULL) { > + dev_err(&pdev->dev, "failed to allocate iio device\n"); > + err = -ENOMEM; > + goto err_ret; > + } > + adc_dev = iio_priv(indio_dev); > + > + adc_dev->mfd_tscadc = tscadc_dev; > + adc_dev->channels = pdata->adc_init->adc_channels; > + > + indio_dev->dev.parent = &pdev->dev; > + indio_dev->name = dev_name(&pdev->dev); > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->info = &tiadc_info; > + > + adc_step_config(adc_dev); > + > + err = tiadc_channel_init(indio_dev, adc_dev->channels); > + if (err < 0) > + goto err_free_device; > + > + err = iio_device_register(indio_dev); > + if (err) > + goto err_free_channels; > + > + platform_set_drvdata(pdev, indio_dev); > + > + return 0; > + > +err_free_channels: > + tiadc_channels_remove(indio_dev); > +err_free_device: > + iio_device_free(indio_dev); > +err_ret: > + return err; > +} > + > +static int __devexit tiadc_remove(struct platform_device *pdev) > +{ > + struct iio_dev *indio_dev = platform_get_drvdata(pdev); > + > + iio_device_unregister(indio_dev); > + tiadc_channels_remove(indio_dev); > + > + iio_device_free(indio_dev); > + > + return 0; > +} > + > +static struct platform_driver tiadc_driver = { > + .driver = { > + .name = "tiadc", > + .owner = THIS_MODULE, > + }, > + .probe = tiadc_probe, > + .remove = __devexit_p(tiadc_remove), > +}; > + > +module_platform_driver(tiadc_driver); > + > +MODULE_DESCRIPTION("TI ADC controller driver"); > +MODULE_AUTHOR("Rachna Patil <rac...@ti.com>"); > +MODULE_LICENSE("GPL"); > diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c > index 168313e..45d66e5 100644 > --- a/drivers/mfd/ti_am335x_tscadc.c > +++ b/drivers/mfd/ti_am335x_tscadc.c > @@ -23,6 +23,7 @@ > #include <linux/pm_runtime.h> > #include <linux/mfd/ti_am335x_tscadc.h> > #include <linux/input/ti_am335x_tsc.h> > +#include <linux/platform_data/ti_am335x_adc.h> > > static unsigned int tscadc_readl(struct ti_tscadc_dev *tsadc, unsigned int > reg) > { > @@ -55,14 +56,23 @@ static int __devinit ti_tscadc_probe(struct > platform_device *pdev) > int irq; > int err, ctrl; > int clk_value, clock_rate; > - int tsc_wires; > + int tsc_wires, adc_channels = 0, total_channels; > > if (!pdata) { > dev_err(&pdev->dev, "Could not find platform data\n"); > return -EINVAL; > } > > + if (pdata->adc_init) > + adc_channels = pdata->adc_init->adc_channels; > + > tsc_wires = pdata->tsc_init->wires; > + total_channels = tsc_wires + adc_channels; > + > + if (total_channels > 8) { > + dev_err(&pdev->dev, "Number of i/p channels more than 8\n"); > + return -EINVAL; > + } > > res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > if (!res) { > @@ -149,6 +159,12 @@ static int __devinit ti_tscadc_probe(struct > platform_device *pdev) > cell->platform_data = tscadc; > cell->pdata_size = sizeof(*tscadc); > > + /* ADC Cell */ > + cell = &tscadc->cells[ADC_CELL]; > + cell->name = "tiadc"; > + cell->platform_data = tscadc; > + cell->pdata_size = sizeof(*tscadc); > + > err = mfd_add_devices(&pdev->dev, pdev->id, tscadc->cells, > TSCADC_CELLS, NULL, 0, NULL); > if (err < 0) > diff --git a/include/linux/mfd/ti_am335x_tscadc.h > b/include/linux/mfd/ti_am335x_tscadc.h > index 458accd..bd9fe1d 100644 > --- a/include/linux/mfd/ti_am335x_tscadc.h > +++ b/include/linux/mfd/ti_am335x_tscadc.h > @@ -117,15 +117,19 @@ > > #define ADC_CLK 3000000 > #define MAX_CLK_DIV 7 > +#define TOTAL_STEPS 16 > +#define TOTAL_CHANNELS 8 > > -#define TSCADC_CELLS 1 > +#define TSCADC_CELLS 2 > > enum tscadc_cells { > TSC_CELL, > + ADC_CELL, > }; > > struct mfd_tscadc_board { > struct tsc_data *tsc_init; > + struct adc_data *adc_init; > }; > > struct ti_tscadc_dev { > @@ -136,6 +140,9 @@ struct ti_tscadc_dev { > > /* tsc device */ > struct tscadc *tsc; > + > + /* adc device */ > + struct adc_device *adc; > }; > > #endif > diff --git a/include/linux/platform_data/ti_am335x_adc.h > b/include/linux/platform_data/ti_am335x_adc.h > new file mode 100644 > index 0000000..e41d583 > --- /dev/null > +++ b/include/linux/platform_data/ti_am335x_adc.h > @@ -0,0 +1,14 @@ > +#ifndef __LINUX_TI_AM335X_ADC_H > +#define __LINUX_TI_AM335X_ADC_H > + > +/** > + * struct adc_data ADC Input information > + * @adc_channels: Number of analog inputs > + * available for ADC. > + */ > + > +struct adc_data { > + unsigned int adc_channels; > +}; > + > +#endif > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
