| /* |
| * 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"); |