From: William Breathitt Gray william.gray@linaro.org
[ Upstream commit 6cfd14c54b1f42f29097244c1b6208f8268d7d5b ]
Reduce magic numbers and improve code readability by implementing and utilizing named register data structures.
Tested-by: Fred Eckert Frede@cmslaser.com Signed-off-by: William Breathitt Gray william.gray@linaro.org Link: https://lore.kernel.org/r/8cb91d5b53e57b066120e42ea07000d6c7ef5543.165721374... Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com Stable-dep-of: 4f9b80aefb9e ("iio: addac: stx104: Fix race condition when converting analog-to-digital") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iio/adc/stx104.c | 74 +++++++++++++++++++++++++++------------- 1 file changed, 50 insertions(+), 24 deletions(-)
diff --git a/drivers/iio/adc/stx104.c b/drivers/iio/adc/stx104.c index 7552351bfed9e..48a91a95e597b 100644 --- a/drivers/iio/adc/stx104.c +++ b/drivers/iio/adc/stx104.c @@ -16,6 +16,7 @@ #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/spinlock.h> +#include <linux/types.h>
#define STX104_OUT_CHAN(chan) { \ .type = IIO_VOLTAGE, \ @@ -44,14 +45,36 @@ static unsigned int num_stx104; module_param_hw_array(base, uint, ioport, &num_stx104, 0); MODULE_PARM_DESC(base, "Apex Embedded Systems STX104 base addresses");
+/** + * struct stx104_reg - device register structure + * @ssr_ad: Software Strobe Register and ADC Data + * @achan: ADC Channel + * @dio: Digital I/O + * @dac: DAC Channels + * @cir_asr: Clear Interrupts and ADC Status + * @acr: ADC Control + * @pccr_fsh: Pacer Clock Control and FIFO Status MSB + * @acfg: ADC Configuration + */ +struct stx104_reg { + u16 ssr_ad; + u8 achan; + u8 dio; + u16 dac[2]; + u8 cir_asr; + u8 acr; + u8 pccr_fsh; + u8 acfg; +}; + /** * struct stx104_iio - IIO device private data structure * @chan_out_states: channels' output states - * @base: base port address of the IIO device + * @reg: I/O address offset for the device registers */ struct stx104_iio { unsigned int chan_out_states[STX104_NUM_OUT_CHAN]; - void __iomem *base; + struct stx104_reg __iomem *reg; };
/** @@ -64,7 +87,7 @@ struct stx104_iio { struct stx104_gpio { struct gpio_chip chip; spinlock_t lock; - void __iomem *base; + u8 __iomem *base; unsigned int out_state; };
@@ -72,6 +95,7 @@ static int stx104_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct stx104_iio *const priv = iio_priv(indio_dev); + struct stx104_reg __iomem *const reg = priv->reg; unsigned int adc_config; int adbu; int gain; @@ -79,7 +103,7 @@ static int stx104_read_raw(struct iio_dev *indio_dev, switch (mask) { case IIO_CHAN_INFO_HARDWAREGAIN: /* get gain configuration */ - adc_config = ioread8(priv->base + 11); + adc_config = ioread8(®->acfg); gain = adc_config & 0x3;
*val = 1 << gain; @@ -91,24 +115,26 @@ static int stx104_read_raw(struct iio_dev *indio_dev, }
/* select ADC channel */ - iowrite8(chan->channel | (chan->channel << 4), priv->base + 2); + iowrite8(chan->channel | (chan->channel << 4), ®->achan);
- /* trigger ADC sample capture and wait for completion */ - iowrite8(0, priv->base); - while (ioread8(priv->base + 8) & BIT(7)); + /* trigger ADC sample capture by writing to the 8-bit + * Software Strobe Register and wait for completion + */ + iowrite8(0, ®->ssr_ad); + while (ioread8(®->cir_asr) & BIT(7));
- *val = ioread16(priv->base); + *val = ioread16(®->ssr_ad); return IIO_VAL_INT; case IIO_CHAN_INFO_OFFSET: /* get ADC bipolar/unipolar configuration */ - adc_config = ioread8(priv->base + 11); + adc_config = ioread8(®->acfg); adbu = !(adc_config & BIT(2));
*val = -32768 * adbu; return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: /* get ADC bipolar/unipolar and gain configuration */ - adc_config = ioread8(priv->base + 11); + adc_config = ioread8(®->acfg); adbu = !(adc_config & BIT(2)); gain = adc_config & 0x3;
@@ -130,16 +156,16 @@ static int stx104_write_raw(struct iio_dev *indio_dev, /* Only four gain states (x1, x2, x4, x8) */ switch (val) { case 1: - iowrite8(0, priv->base + 11); + iowrite8(0, &priv->reg->acfg); break; case 2: - iowrite8(1, priv->base + 11); + iowrite8(1, &priv->reg->acfg); break; case 4: - iowrite8(2, priv->base + 11); + iowrite8(2, &priv->reg->acfg); break; case 8: - iowrite8(3, priv->base + 11); + iowrite8(3, &priv->reg->acfg); break; default: return -EINVAL; @@ -153,7 +179,7 @@ static int stx104_write_raw(struct iio_dev *indio_dev, return -EINVAL;
priv->chan_out_states[chan->channel] = val; - iowrite16(val, priv->base + 4 + 2 * chan->channel); + iowrite16(val, &priv->reg->dac[chan->channel]);
return 0; } @@ -307,15 +333,15 @@ static int stx104_probe(struct device *dev, unsigned int id) }
priv = iio_priv(indio_dev); - priv->base = devm_ioport_map(dev, base[id], STX104_EXTENT); - if (!priv->base) + priv->reg = devm_ioport_map(dev, base[id], STX104_EXTENT); + if (!priv->reg) return -ENOMEM;
indio_dev->info = &stx104_info; indio_dev->modes = INDIO_DIRECT_MODE;
/* determine if differential inputs */ - if (ioread8(priv->base + 8) & BIT(5)) { + if (ioread8(&priv->reg->cir_asr) & BIT(5)) { indio_dev->num_channels = ARRAY_SIZE(stx104_channels_diff); indio_dev->channels = stx104_channels_diff; } else { @@ -326,14 +352,14 @@ static int stx104_probe(struct device *dev, unsigned int id) indio_dev->name = dev_name(dev);
/* configure device for software trigger operation */ - iowrite8(0, priv->base + 9); + iowrite8(0, &priv->reg->acr);
/* initialize gain setting to x1 */ - iowrite8(0, priv->base + 11); + iowrite8(0, &priv->reg->acfg);
/* initialize DAC output to 0V */ - iowrite16(0, priv->base + 4); - iowrite16(0, priv->base + 6); + iowrite16(0, &priv->reg->dac[0]); + iowrite16(0, &priv->reg->dac[1]);
stx104gpio->chip.label = dev_name(dev); stx104gpio->chip.parent = dev; @@ -348,7 +374,7 @@ static int stx104_probe(struct device *dev, unsigned int id) stx104gpio->chip.get_multiple = stx104_gpio_get_multiple; stx104gpio->chip.set = stx104_gpio_set; stx104gpio->chip.set_multiple = stx104_gpio_set_multiple; - stx104gpio->base = priv->base + 3; + stx104gpio->base = &priv->reg->dio; stx104gpio->out_state = 0x0;
spin_lock_init(&stx104gpio->lock);