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Diffstat (limited to 'drivers/staging/iio/adc/mxs-lradc.c')
-rw-r--r--drivers/staging/iio/adc/mxs-lradc.c311
1 files changed, 296 insertions, 15 deletions
diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c
index e2dd7830b320..df71669bb60e 100644
--- a/drivers/staging/iio/adc/mxs-lradc.c
+++ b/drivers/staging/iio/adc/mxs-lradc.c
@@ -38,6 +38,7 @@
#include <linux/clk.h>
#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
@@ -111,16 +112,59 @@ static const char * const mx28_lradc_irq_names[] = {
struct mxs_lradc_of_config {
const int irq_count;
const char * const *irq_name;
+ const uint32_t *vref_mv;
+};
+
+#define VREF_MV_BASE 1850
+
+static const uint32_t mx23_vref_mv[LRADC_MAX_TOTAL_CHANS] = {
+ VREF_MV_BASE, /* CH0 */
+ VREF_MV_BASE, /* CH1 */
+ VREF_MV_BASE, /* CH2 */
+ VREF_MV_BASE, /* CH3 */
+ VREF_MV_BASE, /* CH4 */
+ VREF_MV_BASE, /* CH5 */
+ VREF_MV_BASE * 2, /* CH6 VDDIO */
+ VREF_MV_BASE * 4, /* CH7 VBATT */
+ VREF_MV_BASE, /* CH8 Temp sense 0 */
+ VREF_MV_BASE, /* CH9 Temp sense 1 */
+ VREF_MV_BASE, /* CH10 */
+ VREF_MV_BASE, /* CH11 */
+ VREF_MV_BASE, /* CH12 USB_DP */
+ VREF_MV_BASE, /* CH13 USB_DN */
+ VREF_MV_BASE, /* CH14 VBG */
+ VREF_MV_BASE * 4, /* CH15 VDD5V */
+};
+
+static const uint32_t mx28_vref_mv[LRADC_MAX_TOTAL_CHANS] = {
+ VREF_MV_BASE, /* CH0 */
+ VREF_MV_BASE, /* CH1 */
+ VREF_MV_BASE, /* CH2 */
+ VREF_MV_BASE, /* CH3 */
+ VREF_MV_BASE, /* CH4 */
+ VREF_MV_BASE, /* CH5 */
+ VREF_MV_BASE, /* CH6 */
+ VREF_MV_BASE * 4, /* CH7 VBATT */
+ VREF_MV_BASE, /* CH8 Temp sense 0 */
+ VREF_MV_BASE, /* CH9 Temp sense 1 */
+ VREF_MV_BASE * 2, /* CH10 VDDIO */
+ VREF_MV_BASE, /* CH11 VTH */
+ VREF_MV_BASE * 2, /* CH12 VDDA */
+ VREF_MV_BASE, /* CH13 VDDD */
+ VREF_MV_BASE, /* CH14 VBG */
+ VREF_MV_BASE * 4, /* CH15 VDD5V */
};
static const struct mxs_lradc_of_config mxs_lradc_of_config[] = {
[IMX23_LRADC] = {
.irq_count = ARRAY_SIZE(mx23_lradc_irq_names),
.irq_name = mx23_lradc_irq_names,
+ .vref_mv = mx23_vref_mv,
},
[IMX28_LRADC] = {
.irq_count = ARRAY_SIZE(mx28_lradc_irq_names),
.irq_name = mx28_lradc_irq_names,
+ .vref_mv = mx28_vref_mv,
},
};
@@ -141,6 +185,16 @@ enum lradc_ts_plate {
LRADC_SAMPLE_VALID,
};
+enum mxs_lradc_divbytwo {
+ MXS_LRADC_DIV_DISABLED = 0,
+ MXS_LRADC_DIV_ENABLED,
+};
+
+struct mxs_lradc_scale {
+ unsigned int integer;
+ unsigned int nano;
+};
+
struct mxs_lradc {
struct device *dev;
void __iomem *base;
@@ -155,6 +209,10 @@ struct mxs_lradc {
struct completion completion;
+ const uint32_t *vref_mv;
+ struct mxs_lradc_scale scale_avail[LRADC_MAX_TOTAL_CHANS][2];
+ unsigned long is_divided;
+
/*
* Touchscreen LRADC channels receives a private slot in the CTRL4
* register, the slot #7. Therefore only 7 slots instead of 8 in the
@@ -243,6 +301,7 @@ struct mxs_lradc {
#define LRADC_CTRL1_LRADC_IRQ_OFFSET 0
#define LRADC_CTRL2 0x20
+#define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET 24
#define LRADC_CTRL2_TEMPSENSE_PWD (1 << 15)
#define LRADC_STATUS 0x40
@@ -759,20 +818,11 @@ static void mxs_lradc_handle_touch(struct mxs_lradc *lradc)
/*
* Raw I/O operations
*/
-static int mxs_lradc_read_raw(struct iio_dev *iio_dev,
- const struct iio_chan_spec *chan,
- int *val, int *val2, long m)
+static int mxs_lradc_read_single(struct iio_dev *iio_dev, int chan, int *val)
{
struct mxs_lradc *lradc = iio_priv(iio_dev);
int ret;
- if (m != IIO_CHAN_INFO_RAW)
- return -EINVAL;
-
- /* Check for invalid channel */
- if (chan->channel > LRADC_MAX_TOTAL_CHANS)
- return -EINVAL;
-
/*
* See if there is no buffered operation in progess. If there is, simply
* bail out. This can be improved to support both buffered and raw IO at
@@ -797,7 +847,7 @@ static int mxs_lradc_read_raw(struct iio_dev *iio_dev,
/* Clean the slot's previous content, then set new one. */
mxs_lradc_reg_clear(lradc, LRADC_CTRL4_LRADCSELECT_MASK(0), LRADC_CTRL4);
- mxs_lradc_reg_set(lradc, chan->channel, LRADC_CTRL4);
+ mxs_lradc_reg_set(lradc, chan, LRADC_CTRL4);
mxs_lradc_reg_wrt(lradc, 0, LRADC_CH(0));
@@ -824,9 +874,206 @@ err:
return ret;
}
+static int mxs_lradc_read_temp(struct iio_dev *iio_dev, int *val)
+{
+ int ret, min, max;
+
+ ret = mxs_lradc_read_single(iio_dev, 8, &min);
+ if (ret != IIO_VAL_INT)
+ return ret;
+
+ ret = mxs_lradc_read_single(iio_dev, 9, &max);
+ if (ret != IIO_VAL_INT)
+ return ret;
+
+ *val = max - min;
+
+ return IIO_VAL_INT;
+}
+
+static int mxs_lradc_read_raw(struct iio_dev *iio_dev,
+ const struct iio_chan_spec *chan,
+ int *val, int *val2, long m)
+{
+ struct mxs_lradc *lradc = iio_priv(iio_dev);
+
+ /* Check for invalid channel */
+ if (chan->channel > LRADC_MAX_TOTAL_CHANS)
+ return -EINVAL;
+
+ switch (m) {
+ case IIO_CHAN_INFO_RAW:
+ if (chan->type == IIO_TEMP)
+ return mxs_lradc_read_temp(iio_dev, val);
+
+ return mxs_lradc_read_single(iio_dev, chan->channel, val);
+
+ case IIO_CHAN_INFO_SCALE:
+ if (chan->type == IIO_TEMP) {
+ /* From the datasheet, we have to multiply by 1.012 and
+ * divide by 4
+ */
+ *val = 0;
+ *val2 = 253000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+
+ *val = lradc->vref_mv[chan->channel];
+ *val2 = chan->scan_type.realbits -
+ test_bit(chan->channel, &lradc->is_divided);
+ return IIO_VAL_FRACTIONAL_LOG2;
+
+ case IIO_CHAN_INFO_OFFSET:
+ if (chan->type == IIO_TEMP) {
+ /* The calculated value from the ADC is in Kelvin, we
+ * want Celsius for hwmon so the offset is
+ * -272.15 * scale
+ */
+ *val = -1075;
+ *val2 = 691699;
+
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+
+ return -EINVAL;
+
+ default:
+ break;
+ }
+
+ return -EINVAL;
+}
+
+static int mxs_lradc_write_raw(struct iio_dev *iio_dev,
+ const struct iio_chan_spec *chan,
+ int val, int val2, long m)
+{
+ struct mxs_lradc *lradc = iio_priv(iio_dev);
+ struct mxs_lradc_scale *scale_avail =
+ lradc->scale_avail[chan->channel];
+ int ret;
+
+ ret = mutex_trylock(&lradc->lock);
+ if (!ret)
+ return -EBUSY;
+
+ switch (m) {
+ case IIO_CHAN_INFO_SCALE:
+ ret = -EINVAL;
+ if (val == scale_avail[MXS_LRADC_DIV_DISABLED].integer &&
+ val2 == scale_avail[MXS_LRADC_DIV_DISABLED].nano) {
+ /* divider by two disabled */
+ writel(1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
+ lradc->base + LRADC_CTRL2 + STMP_OFFSET_REG_CLR);
+ clear_bit(chan->channel, &lradc->is_divided);
+ ret = 0;
+ } else if (val == scale_avail[MXS_LRADC_DIV_ENABLED].integer &&
+ val2 == scale_avail[MXS_LRADC_DIV_ENABLED].nano) {
+ /* divider by two enabled */
+ writel(1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
+ lradc->base + LRADC_CTRL2 + STMP_OFFSET_REG_SET);
+ set_bit(chan->channel, &lradc->is_divided);
+ ret = 0;
+ }
+
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ mutex_unlock(&lradc->lock);
+
+ return ret;
+}
+
+static int mxs_lradc_write_raw_get_fmt(struct iio_dev *iio_dev,
+ const struct iio_chan_spec *chan,
+ long m)
+{
+ return IIO_VAL_INT_PLUS_NANO;
+}
+
+static ssize_t mxs_lradc_show_scale_available_ch(struct device *dev,
+ struct device_attribute *attr,
+ char *buf,
+ int ch)
+{
+ struct iio_dev *iio = dev_to_iio_dev(dev);
+ struct mxs_lradc *lradc = iio_priv(iio);
+ int i, len = 0;
+
+ for (i = 0; i < ARRAY_SIZE(lradc->scale_avail[ch]); i++)
+ len += sprintf(buf + len, "%d.%09u ",
+ lradc->scale_avail[ch][i].integer,
+ lradc->scale_avail[ch][i].nano);
+
+ len += sprintf(buf + len, "\n");
+
+ return len;
+}
+
+static ssize_t mxs_lradc_show_scale_available(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev_attr *iio_attr = to_iio_dev_attr(attr);
+
+ return mxs_lradc_show_scale_available_ch(dev, attr, buf,
+ iio_attr->address);
+}
+
+#define SHOW_SCALE_AVAILABLE_ATTR(ch) \
+static IIO_DEVICE_ATTR(in_voltage##ch##_scale_available, S_IRUGO, \
+ mxs_lradc_show_scale_available, NULL, ch)
+
+SHOW_SCALE_AVAILABLE_ATTR(0);
+SHOW_SCALE_AVAILABLE_ATTR(1);
+SHOW_SCALE_AVAILABLE_ATTR(2);
+SHOW_SCALE_AVAILABLE_ATTR(3);
+SHOW_SCALE_AVAILABLE_ATTR(4);
+SHOW_SCALE_AVAILABLE_ATTR(5);
+SHOW_SCALE_AVAILABLE_ATTR(6);
+SHOW_SCALE_AVAILABLE_ATTR(7);
+SHOW_SCALE_AVAILABLE_ATTR(8);
+SHOW_SCALE_AVAILABLE_ATTR(9);
+SHOW_SCALE_AVAILABLE_ATTR(10);
+SHOW_SCALE_AVAILABLE_ATTR(11);
+SHOW_SCALE_AVAILABLE_ATTR(12);
+SHOW_SCALE_AVAILABLE_ATTR(13);
+SHOW_SCALE_AVAILABLE_ATTR(14);
+SHOW_SCALE_AVAILABLE_ATTR(15);
+
+static struct attribute *mxs_lradc_attributes[] = {
+ &iio_dev_attr_in_voltage0_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage1_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage2_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage3_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage4_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage5_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage6_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage7_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage8_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage9_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage10_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage11_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage12_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage13_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage14_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_voltage15_scale_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group mxs_lradc_attribute_group = {
+ .attrs = mxs_lradc_attributes,
+};
+
static const struct iio_info mxs_lradc_iio_info = {
.driver_module = THIS_MODULE,
.read_raw = mxs_lradc_read_raw,
+ .write_raw = mxs_lradc_write_raw,
+ .write_raw_get_fmt = mxs_lradc_write_raw_get_fmt,
+ .attrs = &mxs_lradc_attribute_group,
};
static int mxs_lradc_ts_open(struct input_dev *dev)
@@ -1133,8 +1380,10 @@ static const struct iio_buffer_setup_ops mxs_lradc_buffer_ops = {
.type = (chan_type), \
.indexed = 1, \
.scan_index = (idx), \
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
.channel = (idx), \
+ .address = (idx), \
.scan_type = { \
.sign = 'u', \
.realbits = LRADC_RESOLUTION, \
@@ -1151,8 +1400,17 @@ static const struct iio_chan_spec mxs_lradc_chan_spec[] = {
MXS_ADC_CHAN(5, IIO_VOLTAGE),
MXS_ADC_CHAN(6, IIO_VOLTAGE),
MXS_ADC_CHAN(7, IIO_VOLTAGE), /* VBATT */
- MXS_ADC_CHAN(8, IIO_TEMP), /* Temp sense 0 */
- MXS_ADC_CHAN(9, IIO_TEMP), /* Temp sense 1 */
+ /* Combined Temperature sensors */
+ {
+ .type = IIO_TEMP,
+ .indexed = 1,
+ .scan_index = 8,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_OFFSET) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ .channel = 8,
+ .scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
+ },
MXS_ADC_CHAN(10, IIO_VOLTAGE), /* VDDIO */
MXS_ADC_CHAN(11, IIO_VOLTAGE), /* VTH */
MXS_ADC_CHAN(12, IIO_VOLTAGE), /* VDDA */
@@ -1271,7 +1529,8 @@ static int mxs_lradc_probe(struct platform_device *pdev)
struct iio_dev *iio;
struct resource *iores;
int ret = 0, touch_ret;
- int i;
+ int i, s;
+ unsigned int scale_uv;
/* Allocate the IIO device. */
iio = devm_iio_device_alloc(dev, sizeof(*lradc));
@@ -1316,6 +1575,8 @@ static int mxs_lradc_probe(struct platform_device *pdev)
return ret;
}
+ lradc->vref_mv = of_cfg->vref_mv;
+
platform_set_drvdata(pdev, iio);
init_completion(&lradc->completion);
@@ -1339,6 +1600,26 @@ static int mxs_lradc_probe(struct platform_device *pdev)
if (ret)
goto err_trig;
+ /* Populate available ADC input ranges */
+ for (i = 0; i < LRADC_MAX_TOTAL_CHANS; i++) {
+ for (s = 0; s < ARRAY_SIZE(lradc->scale_avail[i]); s++) {
+ /*
+ * [s=0] = optional divider by two disabled (default)
+ * [s=1] = optional divider by two enabled
+ *
+ * The scale is calculated by doing:
+ * Vref >> (realbits - s)
+ * which multiplies by two on the second component
+ * of the array.
+ */
+ scale_uv = ((u64)lradc->vref_mv[i] * 100000000) >>
+ (iio->channels[i].scan_type.realbits - s);
+ lradc->scale_avail[i][s].nano =
+ do_div(scale_uv, 100000000) * 10;
+ lradc->scale_avail[i][s].integer = scale_uv;
+ }
+ }
+
/* Configure the hardware. */
ret = mxs_lradc_hw_init(lradc);
if (ret)