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-rw-r--r--drivers/iio/adc/vf610_adc.c989
1 files changed, 989 insertions, 0 deletions
diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c
new file mode 100644
index 0000000000..ae31aafd26
--- /dev/null
+++ b/drivers/iio/adc/vf610_adc.c
@@ -0,0 +1,989 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Freescale Vybrid vf610 ADC driver
+ *
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ */
+
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/property.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/regulator/consumer.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;
+
+ /* lock to protect against multiple access to the device */
+ struct mutex lock;
+
+ 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(&info->lock);
+ info->adc_feature.conv_mode = mode;
+ vf610_adc_calculate_rates(info);
+ vf610_adc_hw_init(info);
+ mutex_unlock(&info->lock);
+
+ 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_sample(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val)
+{
+ struct vf610_adc *info = iio_priv(indio_dev);
+ unsigned int hc_cfg;
+ int ret;
+
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+
+ mutex_lock(&info->lock);
+ 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) {
+ ret = -ETIMEDOUT;
+ goto out_unlock;
+ }
+
+ if (ret < 0)
+ goto out_unlock;
+
+ 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:
+ ret = -EINVAL;
+ break;
+ }
+
+out_unlock:
+ mutex_unlock(&info->lock);
+ iio_device_release_direct_mode(indio_dev);
+
+ return ret;
+}
+
+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);
+ long ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ case IIO_CHAN_INFO_PROCESSED:
+ ret = vf610_read_sample(indio_dev, chan, val);
+ if (ret < 0)
+ return ret;
+
+ 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 val;
+
+ 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 0;
+}
+
+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 device *dev = &pdev->dev;
+ struct vf610_adc *info;
+ struct iio_dev *indio_dev;
+ 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;
+
+ info->regs = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(info->regs))
+ return PTR_ERR(info->regs);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ 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);
+
+ device_property_read_u32_array(dev, "fsl,adck-max-frequency", info->max_adck_rate, 3);
+
+ info->adc_feature.default_sample_time = DEFAULT_SAMPLE_TIME;
+ device_property_read_u32(dev, "min-sample-time", &info->adc_feature.default_sample_time);
+
+ platform_set_drvdata(pdev, indio_dev);
+
+ init_completion(&info->completion);
+
+ indio_dev->name = dev_name(&pdev->dev);
+ 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;
+ }
+
+ mutex_init(&info->lock);
+
+ 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;
+}
+
+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;
+}
+
+static DEFINE_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 = pm_sleep_ptr(&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");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-25 03:46:08 +0000