diff options
Diffstat (limited to 'drivers/iio/adc/vf610_adc.c')
| -rw-r--r-- | drivers/iio/adc/vf610_adc.c | 997 |
1 files changed, 997 insertions, 0 deletions
diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c new file mode 100644 index 000000000..3e480244a --- /dev/null +++ b/drivers/iio/adc/vf610_adc.c @@ -0,0 +1,997 @@ +/* + * Freescale Vybrid vf610 ADC driver + * + * Copyright 2013 Freescale Semiconductor, Inc. + * + * 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/delay.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/regulator/consumer.h> +#include <linux/of_platform.h> +#include <linux/err.h> + +#include <linux/iio/iio.h> +#include <linux/iio/buffer.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/trigger.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> + +/* This will be the driver name the kernel reports */ +#define DRIVER_NAME "vf610-adc" + +/* Vybrid/IMX ADC registers */ +#define VF610_REG_ADC_HC0 0x00 +#define VF610_REG_ADC_HC1 0x04 +#define VF610_REG_ADC_HS 0x08 +#define VF610_REG_ADC_R0 0x0c +#define VF610_REG_ADC_R1 0x10 +#define VF610_REG_ADC_CFG 0x14 +#define VF610_REG_ADC_GC 0x18 +#define VF610_REG_ADC_GS 0x1c +#define VF610_REG_ADC_CV 0x20 +#define VF610_REG_ADC_OFS 0x24 +#define VF610_REG_ADC_CAL 0x28 +#define VF610_REG_ADC_PCTL 0x30 + +/* Configuration register field define */ +#define VF610_ADC_MODE_BIT8 0x00 +#define VF610_ADC_MODE_BIT10 0x04 +#define VF610_ADC_MODE_BIT12 0x08 +#define VF610_ADC_MODE_MASK 0x0c +#define VF610_ADC_BUSCLK2_SEL 0x01 +#define VF610_ADC_ALTCLK_SEL 0x02 +#define VF610_ADC_ADACK_SEL 0x03 +#define VF610_ADC_ADCCLK_MASK 0x03 +#define VF610_ADC_CLK_DIV2 0x20 +#define VF610_ADC_CLK_DIV4 0x40 +#define VF610_ADC_CLK_DIV8 0x60 +#define VF610_ADC_CLK_MASK 0x60 +#define VF610_ADC_ADLSMP_LONG 0x10 +#define VF610_ADC_ADSTS_SHORT 0x100 +#define VF610_ADC_ADSTS_NORMAL 0x200 +#define VF610_ADC_ADSTS_LONG 0x300 +#define VF610_ADC_ADSTS_MASK 0x300 +#define VF610_ADC_ADLPC_EN 0x80 +#define VF610_ADC_ADHSC_EN 0x400 +#define VF610_ADC_REFSEL_VALT 0x800 +#define VF610_ADC_REFSEL_VBG 0x1000 +#define VF610_ADC_ADTRG_HARD 0x2000 +#define VF610_ADC_AVGS_8 0x4000 +#define VF610_ADC_AVGS_16 0x8000 +#define VF610_ADC_AVGS_32 0xC000 +#define VF610_ADC_AVGS_MASK 0xC000 +#define VF610_ADC_OVWREN 0x10000 + +/* General control register field define */ +#define VF610_ADC_ADACKEN 0x1 +#define VF610_ADC_DMAEN 0x2 +#define VF610_ADC_ACREN 0x4 +#define VF610_ADC_ACFGT 0x8 +#define VF610_ADC_ACFE 0x10 +#define VF610_ADC_AVGEN 0x20 +#define VF610_ADC_ADCON 0x40 +#define VF610_ADC_CAL 0x80 + +/* Other field define */ +#define VF610_ADC_ADCHC(x) ((x) & 0x1F) +#define VF610_ADC_AIEN (0x1 << 7) +#define VF610_ADC_CONV_DISABLE 0x1F +#define VF610_ADC_HS_COCO0 0x1 +#define VF610_ADC_CALF 0x2 +#define VF610_ADC_TIMEOUT msecs_to_jiffies(100) + +#define DEFAULT_SAMPLE_TIME 1000 + +/* V at 25°C of 696 mV */ +#define VF610_VTEMP25_3V0 950 +/* V at 25°C of 699 mV */ +#define VF610_VTEMP25_3V3 867 +/* Typical sensor slope coefficient at all temperatures */ +#define VF610_TEMP_SLOPE_COEFF 1840 + +enum clk_sel { + VF610_ADCIOC_BUSCLK_SET, + VF610_ADCIOC_ALTCLK_SET, + VF610_ADCIOC_ADACK_SET, +}; + +enum vol_ref { + VF610_ADCIOC_VR_VREF_SET, + VF610_ADCIOC_VR_VALT_SET, + VF610_ADCIOC_VR_VBG_SET, +}; + +enum average_sel { + VF610_ADC_SAMPLE_1, + VF610_ADC_SAMPLE_4, + VF610_ADC_SAMPLE_8, + VF610_ADC_SAMPLE_16, + VF610_ADC_SAMPLE_32, +}; + +enum conversion_mode_sel { + VF610_ADC_CONV_NORMAL, + VF610_ADC_CONV_HIGH_SPEED, + VF610_ADC_CONV_LOW_POWER, +}; + +enum lst_adder_sel { + VF610_ADCK_CYCLES_3, + VF610_ADCK_CYCLES_5, + VF610_ADCK_CYCLES_7, + VF610_ADCK_CYCLES_9, + VF610_ADCK_CYCLES_13, + VF610_ADCK_CYCLES_17, + VF610_ADCK_CYCLES_21, + VF610_ADCK_CYCLES_25, +}; + +struct vf610_adc_feature { + enum clk_sel clk_sel; + enum vol_ref vol_ref; + enum conversion_mode_sel conv_mode; + + int clk_div; + int sample_rate; + int res_mode; + u32 lst_adder_index; + u32 default_sample_time; + + bool calibration; + bool ovwren; +}; + +struct vf610_adc { + struct device *dev; + void __iomem *regs; + struct clk *clk; + + u32 vref_uv; + u32 value; + struct regulator *vref; + + u32 max_adck_rate[3]; + struct vf610_adc_feature adc_feature; + + u32 sample_freq_avail[5]; + + struct completion completion; + /* Ensure the timestamp is naturally aligned */ + struct { + u16 chan; + s64 timestamp __aligned(8); + } scan; +}; + +static const u32 vf610_hw_avgs[] = { 1, 4, 8, 16, 32 }; +static const u32 vf610_lst_adder[] = { 3, 5, 7, 9, 13, 17, 21, 25 }; + +static inline void vf610_adc_calculate_rates(struct vf610_adc *info) +{ + struct vf610_adc_feature *adc_feature = &info->adc_feature; + unsigned long adck_rate, ipg_rate = clk_get_rate(info->clk); + u32 adck_period, lst_addr_min; + int divisor, i; + + adck_rate = info->max_adck_rate[adc_feature->conv_mode]; + + if (adck_rate) { + /* calculate clk divider which is within specification */ + divisor = ipg_rate / adck_rate; + adc_feature->clk_div = 1 << fls(divisor + 1); + } else { + /* fall-back value using a safe divisor */ + adc_feature->clk_div = 8; + } + + adck_rate = ipg_rate / adc_feature->clk_div; + + /* + * Determine the long sample time adder value to be used based + * on the default minimum sample time provided. + */ + adck_period = NSEC_PER_SEC / adck_rate; + lst_addr_min = adc_feature->default_sample_time / adck_period; + for (i = 0; i < ARRAY_SIZE(vf610_lst_adder); i++) { + if (vf610_lst_adder[i] > lst_addr_min) { + adc_feature->lst_adder_index = i; + break; + } + } + + /* + * Calculate ADC sample frequencies + * Sample time unit is ADCK cycles. ADCK clk source is ipg clock, + * which is the same as bus clock. + * + * ADC conversion time = SFCAdder + AverageNum x (BCT + LSTAdder) + * SFCAdder: fixed to 6 ADCK cycles + * AverageNum: 1, 4, 8, 16, 32 samples for hardware average. + * BCT (Base Conversion Time): fixed to 25 ADCK cycles for 12 bit mode + * LSTAdder(Long Sample Time): 3, 5, 7, 9, 13, 17, 21, 25 ADCK cycles + */ + for (i = 0; i < ARRAY_SIZE(vf610_hw_avgs); i++) + info->sample_freq_avail[i] = + adck_rate / (6 + vf610_hw_avgs[i] * + (25 + vf610_lst_adder[adc_feature->lst_adder_index])); +} + +static inline void vf610_adc_cfg_init(struct vf610_adc *info) +{ + struct vf610_adc_feature *adc_feature = &info->adc_feature; + + /* set default Configuration for ADC controller */ + adc_feature->clk_sel = VF610_ADCIOC_BUSCLK_SET; + adc_feature->vol_ref = VF610_ADCIOC_VR_VREF_SET; + + adc_feature->calibration = true; + adc_feature->ovwren = true; + + adc_feature->res_mode = 12; + adc_feature->sample_rate = 1; + + adc_feature->conv_mode = VF610_ADC_CONV_LOW_POWER; + + vf610_adc_calculate_rates(info); +} + +static void vf610_adc_cfg_post_set(struct vf610_adc *info) +{ + struct vf610_adc_feature *adc_feature = &info->adc_feature; + int cfg_data = 0; + int gc_data = 0; + + switch (adc_feature->clk_sel) { + case VF610_ADCIOC_ALTCLK_SET: + cfg_data |= VF610_ADC_ALTCLK_SEL; + break; + case VF610_ADCIOC_ADACK_SET: + cfg_data |= VF610_ADC_ADACK_SEL; + break; + default: + break; + } + + /* low power set for calibration */ + cfg_data |= VF610_ADC_ADLPC_EN; + + /* enable high speed for calibration */ + cfg_data |= VF610_ADC_ADHSC_EN; + + /* voltage reference */ + switch (adc_feature->vol_ref) { + case VF610_ADCIOC_VR_VREF_SET: + break; + case VF610_ADCIOC_VR_VALT_SET: + cfg_data |= VF610_ADC_REFSEL_VALT; + break; + case VF610_ADCIOC_VR_VBG_SET: + cfg_data |= VF610_ADC_REFSEL_VBG; + break; + default: + dev_err(info->dev, "error voltage reference\n"); + } + + /* data overwrite enable */ + if (adc_feature->ovwren) + cfg_data |= VF610_ADC_OVWREN; + + writel(cfg_data, info->regs + VF610_REG_ADC_CFG); + writel(gc_data, info->regs + VF610_REG_ADC_GC); +} + +static void vf610_adc_calibration(struct vf610_adc *info) +{ + int adc_gc, hc_cfg; + + if (!info->adc_feature.calibration) + return; + + /* enable calibration interrupt */ + hc_cfg = VF610_ADC_AIEN | VF610_ADC_CONV_DISABLE; + writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); + + adc_gc = readl(info->regs + VF610_REG_ADC_GC); + writel(adc_gc | VF610_ADC_CAL, info->regs + VF610_REG_ADC_GC); + + if (!wait_for_completion_timeout(&info->completion, VF610_ADC_TIMEOUT)) + dev_err(info->dev, "Timeout for adc calibration\n"); + + adc_gc = readl(info->regs + VF610_REG_ADC_GS); + if (adc_gc & VF610_ADC_CALF) + dev_err(info->dev, "ADC calibration failed\n"); + + info->adc_feature.calibration = false; +} + +static void vf610_adc_cfg_set(struct vf610_adc *info) +{ + struct vf610_adc_feature *adc_feature = &(info->adc_feature); + int cfg_data; + + cfg_data = readl(info->regs + VF610_REG_ADC_CFG); + + cfg_data &= ~VF610_ADC_ADLPC_EN; + if (adc_feature->conv_mode == VF610_ADC_CONV_LOW_POWER) + cfg_data |= VF610_ADC_ADLPC_EN; + + cfg_data &= ~VF610_ADC_ADHSC_EN; + if (adc_feature->conv_mode == VF610_ADC_CONV_HIGH_SPEED) + cfg_data |= VF610_ADC_ADHSC_EN; + + writel(cfg_data, info->regs + VF610_REG_ADC_CFG); +} + +static void vf610_adc_sample_set(struct vf610_adc *info) +{ + struct vf610_adc_feature *adc_feature = &(info->adc_feature); + int cfg_data, gc_data; + + cfg_data = readl(info->regs + VF610_REG_ADC_CFG); + gc_data = readl(info->regs + VF610_REG_ADC_GC); + + /* resolution mode */ + cfg_data &= ~VF610_ADC_MODE_MASK; + switch (adc_feature->res_mode) { + case 8: + cfg_data |= VF610_ADC_MODE_BIT8; + break; + case 10: + cfg_data |= VF610_ADC_MODE_BIT10; + break; + case 12: + cfg_data |= VF610_ADC_MODE_BIT12; + break; + default: + dev_err(info->dev, "error resolution mode\n"); + break; + } + + /* clock select and clock divider */ + cfg_data &= ~(VF610_ADC_CLK_MASK | VF610_ADC_ADCCLK_MASK); + switch (adc_feature->clk_div) { + case 1: + break; + case 2: + cfg_data |= VF610_ADC_CLK_DIV2; + break; + case 4: + cfg_data |= VF610_ADC_CLK_DIV4; + break; + case 8: + cfg_data |= VF610_ADC_CLK_DIV8; + break; + case 16: + switch (adc_feature->clk_sel) { + case VF610_ADCIOC_BUSCLK_SET: + cfg_data |= VF610_ADC_BUSCLK2_SEL | VF610_ADC_CLK_DIV8; + break; + default: + dev_err(info->dev, "error clk divider\n"); + break; + } + break; + } + + /* + * Set ADLSMP and ADSTS based on the Long Sample Time Adder value + * determined. + */ + switch (adc_feature->lst_adder_index) { + case VF610_ADCK_CYCLES_3: + break; + case VF610_ADCK_CYCLES_5: + cfg_data |= VF610_ADC_ADSTS_SHORT; + break; + case VF610_ADCK_CYCLES_7: + cfg_data |= VF610_ADC_ADSTS_NORMAL; + break; + case VF610_ADCK_CYCLES_9: + cfg_data |= VF610_ADC_ADSTS_LONG; + break; + case VF610_ADCK_CYCLES_13: + cfg_data |= VF610_ADC_ADLSMP_LONG; + break; + case VF610_ADCK_CYCLES_17: + cfg_data |= VF610_ADC_ADLSMP_LONG; + cfg_data |= VF610_ADC_ADSTS_SHORT; + break; + case VF610_ADCK_CYCLES_21: + cfg_data |= VF610_ADC_ADLSMP_LONG; + cfg_data |= VF610_ADC_ADSTS_NORMAL; + break; + case VF610_ADCK_CYCLES_25: + cfg_data |= VF610_ADC_ADLSMP_LONG; + cfg_data |= VF610_ADC_ADSTS_NORMAL; + break; + default: + dev_err(info->dev, "error in sample time select\n"); + } + + /* update hardware average selection */ + cfg_data &= ~VF610_ADC_AVGS_MASK; + gc_data &= ~VF610_ADC_AVGEN; + switch (adc_feature->sample_rate) { + case VF610_ADC_SAMPLE_1: + break; + case VF610_ADC_SAMPLE_4: + gc_data |= VF610_ADC_AVGEN; + break; + case VF610_ADC_SAMPLE_8: + gc_data |= VF610_ADC_AVGEN; + cfg_data |= VF610_ADC_AVGS_8; + break; + case VF610_ADC_SAMPLE_16: + gc_data |= VF610_ADC_AVGEN; + cfg_data |= VF610_ADC_AVGS_16; + break; + case VF610_ADC_SAMPLE_32: + gc_data |= VF610_ADC_AVGEN; + cfg_data |= VF610_ADC_AVGS_32; + break; + default: + dev_err(info->dev, + "error hardware sample average select\n"); + } + + writel(cfg_data, info->regs + VF610_REG_ADC_CFG); + writel(gc_data, info->regs + VF610_REG_ADC_GC); +} + +static void vf610_adc_hw_init(struct vf610_adc *info) +{ + /* CFG: Feature set */ + vf610_adc_cfg_post_set(info); + vf610_adc_sample_set(info); + + /* adc calibration */ + vf610_adc_calibration(info); + + /* CFG: power and speed set */ + vf610_adc_cfg_set(info); +} + +static int vf610_set_conversion_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + unsigned int mode) +{ + struct vf610_adc *info = iio_priv(indio_dev); + + mutex_lock(&indio_dev->mlock); + info->adc_feature.conv_mode = mode; + vf610_adc_calculate_rates(info); + vf610_adc_hw_init(info); + mutex_unlock(&indio_dev->mlock); + + return 0; +} + +static int vf610_get_conversion_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct vf610_adc *info = iio_priv(indio_dev); + + return info->adc_feature.conv_mode; +} + +static const char * const vf610_conv_modes[] = { "normal", "high-speed", + "low-power" }; + +static const struct iio_enum vf610_conversion_mode = { + .items = vf610_conv_modes, + .num_items = ARRAY_SIZE(vf610_conv_modes), + .get = vf610_get_conversion_mode, + .set = vf610_set_conversion_mode, +}; + +static const struct iio_chan_spec_ext_info vf610_ext_info[] = { + IIO_ENUM("conversion_mode", IIO_SHARED_BY_DIR, &vf610_conversion_mode), + {}, +}; + +#define VF610_ADC_CHAN(_idx, _chan_type) { \ + .type = (_chan_type), \ + .indexed = 1, \ + .channel = (_idx), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .ext_info = vf610_ext_info, \ + .scan_index = (_idx), \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 12, \ + .storagebits = 16, \ + }, \ +} + +#define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) { \ + .type = (_chan_type), \ + .channel = (_idx), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \ + .scan_index = (_idx), \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 12, \ + .storagebits = 16, \ + }, \ +} + +static const struct iio_chan_spec vf610_adc_iio_channels[] = { + VF610_ADC_CHAN(0, IIO_VOLTAGE), + VF610_ADC_CHAN(1, IIO_VOLTAGE), + VF610_ADC_CHAN(2, IIO_VOLTAGE), + VF610_ADC_CHAN(3, IIO_VOLTAGE), + VF610_ADC_CHAN(4, IIO_VOLTAGE), + VF610_ADC_CHAN(5, IIO_VOLTAGE), + VF610_ADC_CHAN(6, IIO_VOLTAGE), + VF610_ADC_CHAN(7, IIO_VOLTAGE), + VF610_ADC_CHAN(8, IIO_VOLTAGE), + VF610_ADC_CHAN(9, IIO_VOLTAGE), + VF610_ADC_CHAN(10, IIO_VOLTAGE), + VF610_ADC_CHAN(11, IIO_VOLTAGE), + VF610_ADC_CHAN(12, IIO_VOLTAGE), + VF610_ADC_CHAN(13, IIO_VOLTAGE), + VF610_ADC_CHAN(14, IIO_VOLTAGE), + VF610_ADC_CHAN(15, IIO_VOLTAGE), + VF610_ADC_TEMPERATURE_CHAN(26, IIO_TEMP), + IIO_CHAN_SOFT_TIMESTAMP(32), + /* sentinel */ +}; + +static int vf610_adc_read_data(struct vf610_adc *info) +{ + int result; + + result = readl(info->regs + VF610_REG_ADC_R0); + + switch (info->adc_feature.res_mode) { + case 8: + result &= 0xFF; + break; + case 10: + result &= 0x3FF; + break; + case 12: + result &= 0xFFF; + break; + default: + break; + } + + return result; +} + +static irqreturn_t vf610_adc_isr(int irq, void *dev_id) +{ + struct iio_dev *indio_dev = dev_id; + struct vf610_adc *info = iio_priv(indio_dev); + int coco; + + coco = readl(info->regs + VF610_REG_ADC_HS); + if (coco & VF610_ADC_HS_COCO0) { + info->value = vf610_adc_read_data(info); + if (iio_buffer_enabled(indio_dev)) { + info->scan.chan = info->value; + iio_push_to_buffers_with_timestamp(indio_dev, + &info->scan, + iio_get_time_ns(indio_dev)); + iio_trigger_notify_done(indio_dev->trig); + } else + complete(&info->completion); + } + + return IRQ_HANDLED; +} + +static ssize_t vf610_show_samp_freq_avail(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct vf610_adc *info = iio_priv(dev_to_iio_dev(dev)); + size_t len = 0; + int i; + + for (i = 0; i < ARRAY_SIZE(info->sample_freq_avail); i++) + len += scnprintf(buf + len, PAGE_SIZE - len, + "%u ", info->sample_freq_avail[i]); + + /* replace trailing space by newline */ + buf[len - 1] = '\n'; + + return len; +} + +static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(vf610_show_samp_freq_avail); + +static struct attribute *vf610_attributes[] = { + &iio_dev_attr_sampling_frequency_available.dev_attr.attr, + NULL +}; + +static const struct attribute_group vf610_attribute_group = { + .attrs = vf610_attributes, +}; + +static int vf610_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long mask) +{ + struct vf610_adc *info = iio_priv(indio_dev); + unsigned int hc_cfg; + long ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + case IIO_CHAN_INFO_PROCESSED: + mutex_lock(&indio_dev->mlock); + if (iio_buffer_enabled(indio_dev)) { + mutex_unlock(&indio_dev->mlock); + return -EBUSY; + } + + reinit_completion(&info->completion); + hc_cfg = VF610_ADC_ADCHC(chan->channel); + hc_cfg |= VF610_ADC_AIEN; + writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); + ret = wait_for_completion_interruptible_timeout + (&info->completion, VF610_ADC_TIMEOUT); + if (ret == 0) { + mutex_unlock(&indio_dev->mlock); + return -ETIMEDOUT; + } + if (ret < 0) { + mutex_unlock(&indio_dev->mlock); + return ret; + } + + switch (chan->type) { + case IIO_VOLTAGE: + *val = info->value; + break; + case IIO_TEMP: + /* + * Calculate in degree Celsius times 1000 + * Using the typical sensor slope of 1.84 mV/°C + * and VREFH_ADC at 3.3V, V at 25°C of 699 mV + */ + *val = 25000 - ((int)info->value - VF610_VTEMP25_3V3) * + 1000000 / VF610_TEMP_SLOPE_COEFF; + + break; + default: + mutex_unlock(&indio_dev->mlock); + return -EINVAL; + } + + mutex_unlock(&indio_dev->mlock); + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + *val = info->vref_uv / 1000; + *val2 = info->adc_feature.res_mode; + return IIO_VAL_FRACTIONAL_LOG2; + + case IIO_CHAN_INFO_SAMP_FREQ: + *val = info->sample_freq_avail[info->adc_feature.sample_rate]; + *val2 = 0; + return IIO_VAL_INT; + + default: + break; + } + + return -EINVAL; +} + +static int vf610_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, + int val2, + long mask) +{ + struct vf610_adc *info = iio_priv(indio_dev); + int i; + + switch (mask) { + case IIO_CHAN_INFO_SAMP_FREQ: + for (i = 0; + i < ARRAY_SIZE(info->sample_freq_avail); + i++) + if (val == info->sample_freq_avail[i]) { + info->adc_feature.sample_rate = i; + vf610_adc_sample_set(info); + return 0; + } + break; + + default: + break; + } + + return -EINVAL; +} + +static int vf610_adc_buffer_postenable(struct iio_dev *indio_dev) +{ + struct vf610_adc *info = iio_priv(indio_dev); + unsigned int channel; + int ret; + int val; + + ret = iio_triggered_buffer_postenable(indio_dev); + if (ret) + return ret; + + val = readl(info->regs + VF610_REG_ADC_GC); + val |= VF610_ADC_ADCON; + writel(val, info->regs + VF610_REG_ADC_GC); + + channel = find_first_bit(indio_dev->active_scan_mask, + indio_dev->masklength); + + val = VF610_ADC_ADCHC(channel); + val |= VF610_ADC_AIEN; + + writel(val, info->regs + VF610_REG_ADC_HC0); + + return 0; +} + +static int vf610_adc_buffer_predisable(struct iio_dev *indio_dev) +{ + struct vf610_adc *info = iio_priv(indio_dev); + unsigned int hc_cfg = 0; + int val; + + val = readl(info->regs + VF610_REG_ADC_GC); + val &= ~VF610_ADC_ADCON; + writel(val, info->regs + VF610_REG_ADC_GC); + + hc_cfg |= VF610_ADC_CONV_DISABLE; + hc_cfg &= ~VF610_ADC_AIEN; + + writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); + + return iio_triggered_buffer_predisable(indio_dev); +} + +static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = { + .postenable = &vf610_adc_buffer_postenable, + .predisable = &vf610_adc_buffer_predisable, + .validate_scan_mask = &iio_validate_scan_mask_onehot, +}; + +static int vf610_adc_reg_access(struct iio_dev *indio_dev, + unsigned reg, unsigned writeval, + unsigned *readval) +{ + struct vf610_adc *info = iio_priv(indio_dev); + + if ((readval == NULL) || + ((reg % 4) || (reg > VF610_REG_ADC_PCTL))) + return -EINVAL; + + *readval = readl(info->regs + reg); + + return 0; +} + +static const struct iio_info vf610_adc_iio_info = { + .read_raw = &vf610_read_raw, + .write_raw = &vf610_write_raw, + .debugfs_reg_access = &vf610_adc_reg_access, + .attrs = &vf610_attribute_group, +}; + +static const struct of_device_id vf610_adc_match[] = { + { .compatible = "fsl,vf610-adc", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, vf610_adc_match); + +static int vf610_adc_probe(struct platform_device *pdev) +{ + struct vf610_adc *info; + struct iio_dev *indio_dev; + struct resource *mem; + int irq; + int ret; + + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct vf610_adc)); + if (!indio_dev) { + dev_err(&pdev->dev, "Failed allocating iio device\n"); + return -ENOMEM; + } + + info = iio_priv(indio_dev); + info->dev = &pdev->dev; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + info->regs = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(info->regs)) + return PTR_ERR(info->regs); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "no irq resource?\n"); + return irq; + } + + ret = devm_request_irq(info->dev, irq, + vf610_adc_isr, 0, + dev_name(&pdev->dev), indio_dev); + if (ret < 0) { + dev_err(&pdev->dev, "failed requesting irq, irq = %d\n", irq); + return ret; + } + + info->clk = devm_clk_get(&pdev->dev, "adc"); + if (IS_ERR(info->clk)) { + dev_err(&pdev->dev, "failed getting clock, err = %ld\n", + PTR_ERR(info->clk)); + return PTR_ERR(info->clk); + } + + info->vref = devm_regulator_get(&pdev->dev, "vref"); + if (IS_ERR(info->vref)) + return PTR_ERR(info->vref); + + ret = regulator_enable(info->vref); + if (ret) + return ret; + + info->vref_uv = regulator_get_voltage(info->vref); + + of_property_read_u32_array(pdev->dev.of_node, "fsl,adck-max-frequency", + info->max_adck_rate, 3); + + ret = of_property_read_u32(pdev->dev.of_node, "min-sample-time", + &info->adc_feature.default_sample_time); + if (ret) + info->adc_feature.default_sample_time = DEFAULT_SAMPLE_TIME; + + platform_set_drvdata(pdev, indio_dev); + + init_completion(&info->completion); + + indio_dev->name = dev_name(&pdev->dev); + indio_dev->dev.parent = &pdev->dev; + indio_dev->dev.of_node = pdev->dev.of_node; + indio_dev->info = &vf610_adc_iio_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = vf610_adc_iio_channels; + indio_dev->num_channels = ARRAY_SIZE(vf610_adc_iio_channels); + + ret = clk_prepare_enable(info->clk); + if (ret) { + dev_err(&pdev->dev, + "Could not prepare or enable the clock.\n"); + goto error_adc_clk_enable; + } + + vf610_adc_cfg_init(info); + vf610_adc_hw_init(info); + + ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, + NULL, &iio_triggered_buffer_setup_ops); + if (ret < 0) { + dev_err(&pdev->dev, "Couldn't initialise the buffer\n"); + goto error_iio_device_register; + } + + ret = iio_device_register(indio_dev); + if (ret) { + dev_err(&pdev->dev, "Couldn't register the device.\n"); + goto error_adc_buffer_init; + } + + return 0; + +error_adc_buffer_init: + iio_triggered_buffer_cleanup(indio_dev); +error_iio_device_register: + clk_disable_unprepare(info->clk); +error_adc_clk_enable: + regulator_disable(info->vref); + + return ret; +} + +static int vf610_adc_remove(struct platform_device *pdev) +{ + struct iio_dev *indio_dev = platform_get_drvdata(pdev); + struct vf610_adc *info = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + iio_triggered_buffer_cleanup(indio_dev); + regulator_disable(info->vref); + clk_disable_unprepare(info->clk); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int vf610_adc_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct vf610_adc *info = iio_priv(indio_dev); + int hc_cfg; + + /* ADC controller enters to stop mode */ + hc_cfg = readl(info->regs + VF610_REG_ADC_HC0); + hc_cfg |= VF610_ADC_CONV_DISABLE; + writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); + + clk_disable_unprepare(info->clk); + regulator_disable(info->vref); + + return 0; +} + +static int vf610_adc_resume(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct vf610_adc *info = iio_priv(indio_dev); + int ret; + + ret = regulator_enable(info->vref); + if (ret) + return ret; + + ret = clk_prepare_enable(info->clk); + if (ret) + goto disable_reg; + + vf610_adc_hw_init(info); + + return 0; + +disable_reg: + regulator_disable(info->vref); + return ret; +} +#endif + +static SIMPLE_DEV_PM_OPS(vf610_adc_pm_ops, vf610_adc_suspend, vf610_adc_resume); + +static struct platform_driver vf610_adc_driver = { + .probe = vf610_adc_probe, + .remove = vf610_adc_remove, + .driver = { + .name = DRIVER_NAME, + .of_match_table = vf610_adc_match, + .pm = &vf610_adc_pm_ops, + }, +}; + +module_platform_driver(vf610_adc_driver); + +MODULE_AUTHOR("Fugang Duan <B38611@freescale.com>"); +MODULE_DESCRIPTION("Freescale VF610 ADC driver"); +MODULE_LICENSE("GPL v2"); |