From d5acf5942bf6c7b7b73c7d40466a8478afe284fe Mon Sep 17 00:00:00 2001 From: Hector Palacios Date: Mon, 23 Dec 2013 17:48:00 +0000 Subject: [PATCH] iio: mxs-lradc: add scale_available file to channels Adds in_voltageX_scale_available file for every channel to read the different available scales. There are two scales per channel: [0] = divider_by_two disabled (default) [1] = divider_by_two enabled The scale is a struct made of integer and nano parts to build a long decimal number. Signed-off-by: Hector Palacios Signed-off-by: Alexandre Belloni Acked-by: Marek Vasut Signed-off-by: Jonathan Cameron --- drivers/staging/iio/adc/mxs-lradc.c | 106 +++++++++++++++++++++++++++++++++++- 1 file changed, 105 insertions(+), 1 deletion(-) diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c index 22fef0a..c63b312 100644 --- a/drivers/staging/iio/adc/mxs-lradc.c +++ b/drivers/staging/iio/adc/mxs-lradc.c @@ -38,6 +38,7 @@ #include #include +#include #include #include #include @@ -184,6 +185,11 @@ enum lradc_ts_plate { LRADC_SAMPLE_VALID, }; +struct mxs_lradc_scale { + unsigned int integer; + unsigned int nano; +}; + struct mxs_lradc { struct device *dev; void __iomem *base; @@ -199,6 +205,7 @@ struct mxs_lradc { struct completion completion; const uint32_t *vref_mv; + struct mxs_lradc_scale scale_avail[LRADC_MAX_TOTAL_CHANS][2]; /* * Touchscreen LRADC channels receives a private slot in the CTRL4 @@ -929,9 +936,84 @@ static int mxs_lradc_read_raw(struct iio_dev *iio_dev, return -EINVAL; } +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, + .attrs = &mxs_lradc_attribute_group, }; static int mxs_lradc_ts_open(struct input_dev *dev) @@ -1241,6 +1323,7 @@ static const struct iio_buffer_setup_ops mxs_lradc_buffer_ops = { .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ BIT(IIO_CHAN_INFO_SCALE), \ .channel = (idx), \ + .address = (idx), \ .scan_type = { \ .sign = 'u', \ .realbits = LRADC_RESOLUTION, \ @@ -1386,7 +1469,8 @@ 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)); @@ -1456,6 +1540,26 @@ 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) -- 2.7.4