On 14/01/16 15:38, Ludovic Desroches wrote: > This driver supports the new version of the Atmel ADC device introduced > with the SAMA5D2 SoC family. > > Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx> > Acked-by: Rob Herring <robh@xxxxxxxxxx> Looks good to me. One totally trivial note inline (which I'm not even going to bother changing whilst applying the patch - a good measure of how trivial ;) Applied to the togreg branch of iio.git - initially pushed out as testing for the autobuilders to play with it. Thanks, Jonathan > --- > .../bindings/iio/adc/at91-sama5d2_adc.txt | 28 ++ > drivers/iio/adc/Kconfig | 11 + > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/at91-sama5d2_adc.c | 509 +++++++++++++++++++++ > 4 files changed, 549 insertions(+) > create mode 100644 Documentation/devicetree/bindings/iio/adc/at91-sama5d2_adc.txt > create mode 100644 drivers/iio/adc/at91-sama5d2_adc.c > > diff --git a/Documentation/devicetree/bindings/iio/adc/at91-sama5d2_adc.txt b/Documentation/devicetree/bindings/iio/adc/at91-sama5d2_adc.txt > new file mode 100644 > index 0000000..3223684 > --- /dev/null > +++ b/Documentation/devicetree/bindings/iio/adc/at91-sama5d2_adc.txt > @@ -0,0 +1,28 @@ > +* AT91 SAMA5D2 Analog to Digital Converter (ADC) > + > +Required properties: > + - compatible: Should be "atmel,sama5d2-adc". > + - reg: Should contain ADC registers location and length. > + - interrupts: Should contain the IRQ line for the ADC. > + - clocks: phandle to device clock. > + - clock-names: Must be "adc_clk". > + - vref-supply: Supply used as reference for conversions. > + - vddana-supply: Supply for the adc device. > + - atmel,min-sample-rate-hz: Minimum sampling rate, it depends on SoC. > + - atmel,max-sample-rate-hz: Maximum sampling rate, it depends on SoC. > + - atmel,startup-time-ms: Startup time expressed in ms, it depends on SoC. > + > +Example: > + > +adc: adc@fc030000 { > + compatible = "atmel,sama5d2-adc"; > + reg = <0xfc030000 0x100>; > + interrupts = <40 IRQ_TYPE_LEVEL_HIGH 7>; > + clocks = <&adc_clk>; > + clock-names = "adc_clk"; > + atmel,min-sample-rate-hz = <200000>; > + atmel,max-sample-rate-hz = <20000000>; > + atmel,startup-time-ms = <4>; > + vddana-supply = <&vdd_3v3_lp_reg>; > + vref-supply = <&vdd_3v3_lp_reg>; > +} > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 605ff42..f57b4ea 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -131,6 +131,17 @@ config AT91_ADC > To compile this driver as a module, choose M here: the module will be > called at91_adc. > > +config AT91_SAMA5D2_ADC > + tristate "Atmel AT91 SAMA5D2 ADC" > + depends on ARCH_AT91 > + depends on INPUT > + help > + Say yes here to build support for Atmel SAMA5D2 ADC which is > + available on SAMA5D2 SoC family. > + > + To compile this driver as a module, choose M here: the module will be > + called at91-sama5d2_adc. > + > config AXP288_ADC > tristate "X-Powers AXP288 ADC driver" > depends on MFD_AXP20X > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index 6435780..fb57e12 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -14,6 +14,7 @@ obj-$(CONFIG_AD7793) += ad7793.o > obj-$(CONFIG_AD7887) += ad7887.o > obj-$(CONFIG_AD799X) += ad799x.o > obj-$(CONFIG_AT91_ADC) += at91_adc.o > +obj-$(CONFIG_AT91_SAMA5D2_ADC) += at91-sama5d2_adc.o > obj-$(CONFIG_AXP288_ADC) += axp288_adc.o > obj-$(CONFIG_BERLIN2_ADC) += berlin2-adc.o > obj-$(CONFIG_CC10001_ADC) += cc10001_adc.o > diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c > new file mode 100644 > index 0000000..ecb2d90 > --- /dev/null > +++ b/drivers/iio/adc/at91-sama5d2_adc.c > @@ -0,0 +1,509 @@ > +/* > + * Atmel ADC driver for SAMA5D2 devices and compatible. > + * > + * Copyright (C) 2015 Atmel, > + * 2015 Ludovic Desroches <ludovic.desroches@xxxxxxxxx> > + * > + * This software is licensed under the terms of the GNU General Public > + * License version 2, as published by the Free Software Foundation, and > + * may be copied, distributed, and modified under those terms. > + * > + * 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. > + */ > + > +#include <linux/bitops.h> > +#include <linux/clk.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/module.h> > +#include <linux/of_device.h> > +#include <linux/platform_device.h> > +#include <linux/sched.h> > +#include <linux/wait.h> > +#include <linux/iio/iio.h> > +#include <linux/iio/sysfs.h> > +#include <linux/regulator/consumer.h> > + > +/* Control Register */ > +#define AT91_SAMA5D2_CR 0x00 > +/* Software Reset */ > +#define AT91_SAMA5D2_CR_SWRST BIT(0) > +/* Start Conversion */ > +#define AT91_SAMA5D2_CR_START BIT(1) > +/* Touchscreen Calibration */ > +#define AT91_SAMA5D2_CR_TSCALIB BIT(2) > +/* Comparison Restart */ > +#define AT91_SAMA5D2_CR_CMPRST BIT(4) > + > +/* Mode Register */ > +#define AT91_SAMA5D2_MR 0x04 > +/* Trigger Selection */ > +#define AT91_SAMA5D2_MR_TRGSEL(v) ((v) << 1) > +/* ADTRG */ > +#define AT91_SAMA5D2_MR_TRGSEL_TRIG0 0 > +/* TIOA0 */ > +#define AT91_SAMA5D2_MR_TRGSEL_TRIG1 1 > +/* TIOA1 */ > +#define AT91_SAMA5D2_MR_TRGSEL_TRIG2 2 > +/* TIOA2 */ > +#define AT91_SAMA5D2_MR_TRGSEL_TRIG3 3 > +/* PWM event line 0 */ > +#define AT91_SAMA5D2_MR_TRGSEL_TRIG4 4 > +/* PWM event line 1 */ > +#define AT91_SAMA5D2_MR_TRGSEL_TRIG5 5 > +/* TIOA3 */ > +#define AT91_SAMA5D2_MR_TRGSEL_TRIG6 6 > +/* RTCOUT0 */ > +#define AT91_SAMA5D2_MR_TRGSEL_TRIG7 7 > +/* Sleep Mode */ > +#define AT91_SAMA5D2_MR_SLEEP BIT(5) > +/* Fast Wake Up */ > +#define AT91_SAMA5D2_MR_FWUP BIT(6) > +/* Prescaler Rate Selection */ > +#define AT91_SAMA5D2_MR_PRESCAL(v) ((v) << AT91_SAMA5D2_MR_PRESCAL_OFFSET) > +#define AT91_SAMA5D2_MR_PRESCAL_OFFSET 8 > +#define AT91_SAMA5D2_MR_PRESCAL_MAX 0xff > +/* Startup Time */ > +#define AT91_SAMA5D2_MR_STARTUP(v) ((v) << 16) > +/* Analog Change */ > +#define AT91_SAMA5D2_MR_ANACH BIT(23) > +/* Tracking Time */ > +#define AT91_SAMA5D2_MR_TRACKTIM(v) ((v) << 24) > +#define AT91_SAMA5D2_MR_TRACKTIM_MAX 0xff > +/* Transfer Time */ > +#define AT91_SAMA5D2_MR_TRANSFER(v) ((v) << 28) > +#define AT91_SAMA5D2_MR_TRANSFER_MAX 0x3 > +/* Use Sequence Enable */ > +#define AT91_SAMA5D2_MR_USEQ BIT(31) > + > +/* Channel Sequence Register 1 */ > +#define AT91_SAMA5D2_SEQR1 0x08 > +/* Channel Sequence Register 2 */ > +#define AT91_SAMA5D2_SEQR2 0x0c > +/* Channel Enable Register */ > +#define AT91_SAMA5D2_CHER 0x10 > +/* Channel Disable Register */ > +#define AT91_SAMA5D2_CHDR 0x14 > +/* Channel Status Register */ > +#define AT91_SAMA5D2_CHSR 0x18 > +/* Last Converted Data Register */ > +#define AT91_SAMA5D2_LCDR 0x20 > +/* Interrupt Enable Register */ > +#define AT91_SAMA5D2_IER 0x24 > +/* Interrupt Disable Register */ > +#define AT91_SAMA5D2_IDR 0x28 > +/* Interrupt Mask Register */ > +#define AT91_SAMA5D2_IMR 0x2c > +/* Interrupt Status Register */ > +#define AT91_SAMA5D2_ISR 0x30 > +/* Last Channel Trigger Mode Register */ > +#define AT91_SAMA5D2_LCTMR 0x34 > +/* Last Channel Compare Window Register */ > +#define AT91_SAMA5D2_LCCWR 0x38 > +/* Overrun Status Register */ > +#define AT91_SAMA5D2_OVER 0x3c > +/* Extended Mode Register */ > +#define AT91_SAMA5D2_EMR 0x40 > +/* Compare Window Register */ > +#define AT91_SAMA5D2_CWR 0x44 > +/* Channel Gain Register */ > +#define AT91_SAMA5D2_CGR 0x48 > +/* Channel Offset Register */ > +#define AT91_SAMA5D2_COR 0x4c > +/* Channel Data Register 0 */ > +#define AT91_SAMA5D2_CDR0 0x50 > +/* Analog Control Register */ > +#define AT91_SAMA5D2_ACR 0x94 > +/* Touchscreen Mode Register */ > +#define AT91_SAMA5D2_TSMR 0xb0 > +/* Touchscreen X Position Register */ > +#define AT91_SAMA5D2_XPOSR 0xb4 > +/* Touchscreen Y Position Register */ > +#define AT91_SAMA5D2_YPOSR 0xb8 > +/* Touchscreen Pressure Register */ > +#define AT91_SAMA5D2_PRESSR 0xbc > +/* Trigger Register */ > +#define AT91_SAMA5D2_TRGR 0xc0 > +/* Correction Select Register */ > +#define AT91_SAMA5D2_COSR 0xd0 > +/* Correction Value Register */ > +#define AT91_SAMA5D2_CVR 0xd4 > +/* Channel Error Correction Register */ > +#define AT91_SAMA5D2_CECR 0xd8 > +/* Write Protection Mode Register */ > +#define AT91_SAMA5D2_WPMR 0xe4 > +/* Write Protection Status Register */ > +#define AT91_SAMA5D2_WPSR 0xe8 > +/* Version Register */ > +#define AT91_SAMA5D2_VERSION 0xfc > + > +#define AT91_AT91_SAMA5D2_CHAN(num, addr) \ > + { \ > + .type = IIO_VOLTAGE, \ > + .channel = num, \ > + .address = addr, \ > + .scan_type = { \ > + .sign = 'u', \ > + .realbits = 12, \ > + }, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\ > + .datasheet_name = "CH"#num, \ > + .indexed = 1, \ > + } > + > +#define at91_adc_readl(st, reg) readl_relaxed(st->base + reg) > +#define at91_adc_writel(st, reg, val) writel_relaxed(val, st->base + reg) > + > +struct at91_adc_soc_info { > + unsigned startup_time; > + unsigned min_sample_rate; > + unsigned max_sample_rate; > +}; > + > +struct at91_adc_state { > + void __iomem *base; > + int irq; > + struct clk *per_clk; > + struct regulator *reg; > + struct regulator *vref; > + u32 vref_uv; > + const struct iio_chan_spec *chan; > + bool conversion_done; > + u32 conversion_value; > + struct at91_adc_soc_info soc_info; > + wait_queue_head_t wq_data_available; > + /* > + * lock to prevent concurrent 'single conversion' requests through > + * sysfs. > + */ > + struct mutex lock; > +}; > + > +static const struct iio_chan_spec at91_adc_channels[] = { > + AT91_AT91_SAMA5D2_CHAN(0, 0x50), > + AT91_AT91_SAMA5D2_CHAN(1, 0x54), > + AT91_AT91_SAMA5D2_CHAN(2, 0x58), > + AT91_AT91_SAMA5D2_CHAN(3, 0x5c), > + AT91_AT91_SAMA5D2_CHAN(4, 0x60), > + AT91_AT91_SAMA5D2_CHAN(5, 0x64), > + AT91_AT91_SAMA5D2_CHAN(6, 0x68), > + AT91_AT91_SAMA5D2_CHAN(7, 0x6c), > + AT91_AT91_SAMA5D2_CHAN(8, 0x70), > + AT91_AT91_SAMA5D2_CHAN(9, 0x74), > + AT91_AT91_SAMA5D2_CHAN(10, 0x78), > + AT91_AT91_SAMA5D2_CHAN(11, 0x7c), > +}; > + > +static unsigned at91_adc_startup_time(unsigned startup_time_min, > + unsigned adc_clk_khz) > +{ > + const unsigned startup_lookup[] = { > + 0, 8, 16, 24, > + 64, 80, 96, 112, > + 512, 576, 640, 704, > + 768, 832, 896, 960 > + }; > + unsigned ticks_min, i; > + > + /* > + * Since the adc frequency is checked before, there is no reason > + * to not meet the startup time constraint. > + */ > + > + ticks_min = startup_time_min * adc_clk_khz / 1000; > + for (i = 0; i < ARRAY_SIZE(startup_lookup); i++) > + if (startup_lookup[i] > ticks_min) > + break; > + > + return i; > +} > + > +static void at91_adc_setup_samp_freq(struct at91_adc_state *st, unsigned freq) > +{ > + struct iio_dev *indio_dev = iio_priv_to_dev(st); > + unsigned f_per, prescal, startup; > + > + f_per = clk_get_rate(st->per_clk); > + prescal = (f_per / (2 * freq)) - 1; > + > + startup = at91_adc_startup_time(st->soc_info.startup_time, > + freq / 1000); > + > + at91_adc_writel(st, AT91_SAMA5D2_MR, > + AT91_SAMA5D2_MR_TRANSFER(2) > + | AT91_SAMA5D2_MR_STARTUP(startup) > + | AT91_SAMA5D2_MR_PRESCAL(prescal)); > + > + dev_dbg(&indio_dev->dev, "freq: %u, startup: %u, prescal: %u\n", > + freq, startup, prescal); > +} > + > +static unsigned at91_adc_get_sample_freq(struct at91_adc_state *st) > +{ > + unsigned f_adc, f_per = clk_get_rate(st->per_clk); > + unsigned mr, prescal; > + > + mr = at91_adc_readl(st, AT91_SAMA5D2_MR); > + prescal = (mr >> AT91_SAMA5D2_MR_PRESCAL_OFFSET) > + & AT91_SAMA5D2_MR_PRESCAL_MAX; > + f_adc = f_per / (2 * (prescal + 1)); > + > + return f_adc; > +} > + > +static irqreturn_t at91_adc_interrupt(int irq, void *private) > +{ > + struct iio_dev *indio = private; > + struct at91_adc_state *st = iio_priv(indio); > + u32 status = at91_adc_readl(st, AT91_SAMA5D2_ISR); > + u32 imr = at91_adc_readl(st, AT91_SAMA5D2_IMR); > + > + if (status & imr) { > + st->conversion_value = at91_adc_readl(st, st->chan->address); > + st->conversion_done = true; > + wake_up_interruptible(&st->wq_data_available); > + return IRQ_HANDLED; > + } > + > + return IRQ_NONE; > +} > + > +static int at91_adc_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + struct at91_adc_state *st = iio_priv(indio_dev); > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + mutex_lock(&st->lock); > + > + st->chan = chan; > + > + at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel)); > + at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel)); > + at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_START); > + > + ret = wait_event_interruptible_timeout(st->wq_data_available, > + st->conversion_done, > + msecs_to_jiffies(1000)); > + if (ret == 0) > + ret = -ETIMEDOUT; > + > + if (ret > 0) { > + *val = st->conversion_value; > + ret = IIO_VAL_INT; > + st->conversion_done = false; > + } > + > + at91_adc_writel(st, AT91_SAMA5D2_IDR, BIT(chan->channel)); > + at91_adc_writel(st, AT91_SAMA5D2_CHDR, BIT(chan->channel)); > + > + mutex_unlock(&st->lock); > + return ret; > + > + case IIO_CHAN_INFO_SCALE: > + *val = st->vref_uv / 1000; > + *val2 = chan->scan_type.realbits; > + return IIO_VAL_FRACTIONAL_LOG2; > + > + case IIO_CHAN_INFO_SAMP_FREQ: > + *val = at91_adc_get_sample_freq(st); > + return IIO_VAL_INT; > + > + default: > + return -EINVAL; > + } > +} > + > +static int at91_adc_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int val, int val2, long mask) > +{ > + struct at91_adc_state *st = iio_priv(indio_dev); > + > + if (mask != IIO_CHAN_INFO_SAMP_FREQ) > + return -EINVAL; > + > + if (val < st->soc_info.min_sample_rate || > + val > st->soc_info.max_sample_rate) > + return -EINVAL; > + > + at91_adc_setup_samp_freq(st, val); > + > + return 0; > +} > + > +static const struct iio_info at91_adc_info = { > + .read_raw = &at91_adc_read_raw, > + .write_raw = &at91_adc_write_raw, > + .driver_module = THIS_MODULE, > +}; > + > +static int at91_adc_probe(struct platform_device *pdev) > +{ > + struct iio_dev *indio_dev; > + struct at91_adc_state *st; > + struct resource *res; > + int ret; > + > + indio_dev = devm_iio_device_alloc(&pdev->dev, > + sizeof(struct at91_adc_state)); Utter nitpick that isn't going to hold up the patch... I'd have done this as sizeof(*st)) but really doesn't matter. > + if (!indio_dev) > + return -ENOMEM; > + > + indio_dev->dev.parent = &pdev->dev; > + indio_dev->name = dev_name(&pdev->dev); > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->info = &at91_adc_info; > + indio_dev->channels = at91_adc_channels; > + indio_dev->num_channels = ARRAY_SIZE(at91_adc_channels); > + > + st = iio_priv(indio_dev); > + > + ret = of_property_read_u32(pdev->dev.of_node, > + "atmel,min-sample-rate-hz", > + &st->soc_info.min_sample_rate); > + if (ret) { > + dev_err(&pdev->dev, > + "invalid or missing value for atmel,min-sample-rate-hz\n"); > + return ret; > + } > + > + ret = of_property_read_u32(pdev->dev.of_node, > + "atmel,max-sample-rate-hz", > + &st->soc_info.max_sample_rate); > + if (ret) { > + dev_err(&pdev->dev, > + "invalid or missing value for atmel,max-sample-rate-hz\n"); > + return ret; > + } > + > + ret = of_property_read_u32(pdev->dev.of_node, "atmel,startup-time-ms", > + &st->soc_info.startup_time); > + if (ret) { > + dev_err(&pdev->dev, > + "invalid or missing value for atmel,startup-time-ms\n"); > + return ret; > + } > + > + init_waitqueue_head(&st->wq_data_available); > + mutex_init(&st->lock); > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!res) > + return -EINVAL; > + > + st->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(st->base)) > + return PTR_ERR(st->base); > + > + st->irq = platform_get_irq(pdev, 0); > + if (st->irq <= 0) { > + if (!st->irq) > + st->irq = -ENXIO; > + > + return st->irq; > + } > + > + st->per_clk = devm_clk_get(&pdev->dev, "adc_clk"); > + if (IS_ERR(st->per_clk)) > + return PTR_ERR(st->per_clk); > + > + st->reg = devm_regulator_get(&pdev->dev, "vddana"); > + if (IS_ERR(st->reg)) > + return PTR_ERR(st->reg); > + > + st->vref = devm_regulator_get(&pdev->dev, "vref"); > + if (IS_ERR(st->vref)) > + return PTR_ERR(st->vref); > + > + ret = devm_request_irq(&pdev->dev, st->irq, at91_adc_interrupt, 0, > + pdev->dev.driver->name, indio_dev); > + if (ret) > + return ret; > + > + ret = regulator_enable(st->reg); > + if (ret) > + return ret; > + > + ret = regulator_enable(st->vref); > + if (ret) > + goto reg_disable; > + > + st->vref_uv = regulator_get_voltage(st->vref); > + if (st->vref_uv <= 0) { > + ret = -EINVAL; > + goto vref_disable; > + } > + > + at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_SWRST); > + at91_adc_writel(st, AT91_SAMA5D2_IDR, 0xffffffff); > + > + at91_adc_setup_samp_freq(st, st->soc_info.min_sample_rate); > + > + ret = clk_prepare_enable(st->per_clk); > + if (ret) > + goto vref_disable; > + > + ret = iio_device_register(indio_dev); > + if (ret < 0) > + goto per_clk_disable_unprepare; > + > + dev_info(&pdev->dev, "version: %x\n", > + readl_relaxed(st->base + AT91_SAMA5D2_VERSION)); > + > + return 0; > + > +per_clk_disable_unprepare: > + clk_disable_unprepare(st->per_clk); > +vref_disable: > + regulator_disable(st->vref); > +reg_disable: > + regulator_disable(st->reg); > + return ret; > +} > + > +static int at91_adc_remove(struct platform_device *pdev) > +{ > + struct iio_dev *indio_dev = platform_get_drvdata(pdev); > + struct at91_adc_state *st = iio_priv(indio_dev); > + > + iio_device_unregister(indio_dev); > + > + clk_disable_unprepare(st->per_clk); > + > + regulator_disable(st->vref); > + regulator_disable(st->reg); > + > + return 0; > +} > + > +static const struct of_device_id at91_adc_dt_match[] = { > + { > + .compatible = "atmel,sama5d2-adc", > + }, { > + /* sentinel */ > + } > +}; > +MODULE_DEVICE_TABLE(of, at91_adc_dt_match); > + > +static struct platform_driver at91_adc_driver = { > + .probe = at91_adc_probe, > + .remove = at91_adc_remove, > + .driver = { > + .name = "at91-sama5d2_adc", > + .of_match_table = at91_adc_dt_match, > + }, > +}; > +module_platform_driver(at91_adc_driver) > + > +MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@xxxxxxxxx>"); > +MODULE_DESCRIPTION("Atmel AT91 SAMA5D2 ADC"); > +MODULE_LICENSE("GPL v2"); > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html