> Add IIO driver for the Renesas RCar GyroADC block. This block is a
> simple 4/8-channel ADC which samples 12/15/24 bits of data every
> cycle from all channels.
comments below
> Signed-off-by: Marek Vasut <marek.vasut@xxxxxxxxx>
> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> Cc: Simon Horman <horms+renesas@xxxxxxxxxxxx>
> ---
> .../bindings/iio/adc/renesas,gyroadc.txt | 38 +++
> MAINTAINERS | 6 +
> drivers/iio/adc/Kconfig | 10 +
> drivers/iio/adc/Makefile | 1 +
> drivers/iio/adc/rcar_gyro_adc.c | 379 +++++++++++++++++++++
> 5 files changed, 434 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/adc/renesas,gyroadc.txt
> create mode 100644 drivers/iio/adc/rcar_gyro_adc.c
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/renesas,gyroadc.txt b/Documentation/devicetree/bindings/iio/adc/renesas,gyroadc.txt
> new file mode 100644
> index 0000000..3fd5f57
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/renesas,gyroadc.txt
> @@ -0,0 +1,38 @@
> +* Renesas RCar GyroADC device driver
> +
> +Required properties:
> +- compatible: Should be "renesas,rcar-gyroadc" for regular GyroADC or
> + "renesas,rcar-gyroadc-r8a7792" for GyroADC without interrupt
> + block found in R8A7792.
> +- reg: Address and length of the register set for the device
> +- clocks: References to all the clocks specified in the clock-names
> + property as specified in
> + Documentation/devicetree/bindings/clock/clock-bindings.txt.
> +- clock-names: Shall contain "fck" and "if". The "fck" are the GyroADC block
"fck" is...
> + clock, the "if" are the interface clock.
"if" is ...
> + power-domains = <&sysc R8A7791_PD_ALWAYS_ON>;
this is just an example and not appropriate here?
> +- power-domains: Must contain a reference to the PM domain, if available.
> +- renesas,gyroadc-mode: GyroADC mode of operation, must be either of:
> + 1 - MB88101A mode, 12bit sampling, 4 channels
> + 2 - ADCS7476 mode, 15bit sampling, 8 channels
> + 3 - MAX1162 mode, 16bit sampling, 8 channels
> +- renesas,gyroadc-vref: Array of reference voltage values for each input to
> + the GyroADC, in uV. Array must have 4 elemenets for
elements
> + mode 1 and 8 elements for mode 2 and 3.
> +
> +Example:
> + &adc {
> + compatible = "renesas,rcar-gyroadc";
> + reg = <0 0xe6e54000 0 64>;
> + clocks = <&mstp9_clks R8A7791_CLK_GYROADC>, <&clk_65m>;
> + clock-names = "fck", "if";
> + power-domains = <&sysc R8A7791_PD_ALWAYS_ON>;
> +
> + pinctrl-0 = <&adc_pins>;
> + pinctrl-names = "default";
> +
> + renesas,gyroadc-vref = <4096000 4096000 4096000 4096000
> + 4096000 4096000 4096000 4096000>;
> + renesas,gyroadc-mode = <3>;
> + status = "okay";
> + };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 162d904..751e760 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -10271,6 +10271,12 @@ L: linux-renesas-soc@xxxxxxxxxxxxxxx
> F: drivers/net/ethernet/renesas/
> F: include/linux/sh_eth.h
>
> +RENESAS RCAR GYROADC DRIVER
> +M: Marek Vasut <marek.vasut@xxxxxxxxx>
> +L: linux-iio@xxxxxxxxxxxxxxx
> +S: Supported
> +F: drivers/iio/adc/rcar_gyro_adc.c
> +
> RENESAS USB2 PHY DRIVER
> M: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
> L: linux-renesas-soc@xxxxxxxxxxxxxxx
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> index 99c0514..4a4cac7 100644
> --- a/drivers/iio/adc/Kconfig
> +++ b/drivers/iio/adc/Kconfig
> @@ -408,6 +408,16 @@ config QCOM_SPMI_VADC
> To compile this driver as a module, choose M here: the module will
> be called qcom-spmi-vadc.
>
> +config RCAR_GYRO_ADC
> + tristate "Renesas RCAR GyroADC driver"
> + depends on ARCH_RCAR_GEN2 || (ARM && COMPILE_TEST)
> + help
> + Say yes here to build support for the GyroADC found in Renesas
> + RCar Gen2 SoCs.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called rcar-gyroadc.
called rcar_gyro_adc?
> +
> config ROCKCHIP_SARADC
> tristate "Rockchip SARADC driver"
> depends on ARCH_ROCKCHIP || (ARM && COMPILE_TEST)
> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
> index 7a40c04..253aeb2 100644
> --- a/drivers/iio/adc/Makefile
> +++ b/drivers/iio/adc/Makefile
> @@ -39,6 +39,7 @@ obj-$(CONFIG_NAU7802) += nau7802.o
> obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o
> obj-$(CONFIG_QCOM_SPMI_IADC) += qcom-spmi-iadc.o
> obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-spmi-vadc.o
> +obj-$(CONFIG_RCAR_GYRO_ADC) += rcar_gyro_adc.o
> obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o
> obj-$(CONFIG_STX104) += stx104.o
> obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
> diff --git a/drivers/iio/adc/rcar_gyro_adc.c b/drivers/iio/adc/rcar_gyro_adc.c
> new file mode 100644
> index 0000000..a74b148
> --- /dev/null
> +++ b/drivers/iio/adc/rcar_gyro_adc.c
> @@ -0,0 +1,379 @@
> +/*
> + * Renesas RCar GyroADC driver
> + *
> + * Copyright 2016 Marek Vasut <marek.vasut@xxxxxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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/module.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/of.h>
> +#include <linux/of_irq.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/of_platform.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>
> +
> +/* GyroADC registers. */
> +#define RCAR_GYROADC_MODE_SELECT 0x00
> +#define RCAR_GYROADC_MODE_SELECT_1_MB88101A 0x0
> +#define RCAR_GYROADC_MODE_SELECT_2_ADCS7476 0x1
> +#define RCAR_GYROADC_MODE_SELECT_3_MAX1162 0x3
> +
> +#define RCAR_GYROADC_START_STOP 0x04
> +#define RCAR_GYROADC_START_STOP_START BIT(0)
> +
> +#define RCAR_GYROADC_CLOCK_LENGTH 0x08
> +#define RCAR_GYROADC_1_25MS_LENGTH 0x0c
> +
> +#define RCAR_GYROADC_REALTIME_DATA(ch) (0x10 + ((ch) * 4))
> +#define RCAR_GYROADC_100MS_ADDED_DATA(ch) (0x30 + ((ch) * 4))
> +#define RCAR_GYROADC_10MS_AVG_DATA(ch) (0x50 + ((ch) * 4))
> +
> +#define RCAR_GYROADC_FIFO_STATUS 0x70
> +#define RCAR_GYROADC_FIFO_STATUS_EMPTY(ch) BIT(0 + (4 * (ch)))
FIFO_STATUS_... is not used (yet)
4*ch looks suspicious for ch==8??
> +#define RCAR_GYROADC_FIFO_STATUS_FULL(ch) BIT(1 + (4 * (ch)))
> +#define RCAR_GYROADC_FIFO_STATUS_ERROR(ch) BIT(2 + (4 * (ch)))
> +
> +#define RCAR_GYROADC_INTR 0x74
> +#define RCAR_GYROADC_INTR_INT BIT(0)
> +
> +#define RCAR_GYROADC_INTENR 0x78
> +#define RCAR_GYROADC_INTENR_INTEN BIT(0)
> +
> +#define RCAR_GYROADC_SAMPLE_RATE 800 /* Hz */
> +
> +enum rcar_gyroadc_model {
> + RCAR_GYROADC_MODEL_DEFAULT,
> + RCAR_GYROADC_MODEL_R8A7792,
> +};
> +
> +struct rcar_gyroadc {
> + struct device *dev;
> + void __iomem *regs;
> + struct clk *fclk;
> + struct clk *clk;
> + enum rcar_gyroadc_model model;
> + unsigned int mode;
> + u32 vref_uv[8];
> + u32 buffer[8];
> +};
> +
> +static void rcar_gyroadc_hw_init(struct rcar_gyroadc *priv)
> +{
> + unsigned long clk_mhz = clk_get_rate(priv->clk) / 1000000;
> +
> + /* Stop the GyroADC. */
> + writel(0, priv->regs + RCAR_GYROADC_START_STOP);
> +
> + /* Disable IRQ, except on V2H. */
> + if (priv->model != RCAR_GYROADC_MODEL_R8A7792)
> + writel(0, priv->regs + RCAR_GYROADC_INTENR);
> +
> + /* Set mode and timing. */
> + writel(priv->mode, priv->regs + RCAR_GYROADC_MODE_SELECT);
> +
> + if (priv->mode == RCAR_GYROADC_MODE_SELECT_1_MB88101A)
> + writel(clk_mhz * 10, priv->regs + RCAR_GYROADC_CLOCK_LENGTH);
> + else if (priv->mode == RCAR_GYROADC_MODE_SELECT_2_ADCS7476)
> + writel(clk_mhz * 5, priv->regs + RCAR_GYROADC_CLOCK_LENGTH);
> + else if (priv->mode == RCAR_GYROADC_MODE_SELECT_3_MAX1162)
> + writel(clk_mhz * 5, priv->regs + RCAR_GYROADC_CLOCK_LENGTH);
> + writel(clk_mhz * 1250, priv->regs + RCAR_GYROADC_1_25MS_LENGTH);
> +
> + /*
> + * We can possibly turn the sampling on/off on-demand to reduce power
> + * consumption, but for the sake of quick availability of samples, we
> + * don't do it now.
> + */
> + writel(RCAR_GYROADC_START_STOP_START,
> + priv->regs + RCAR_GYROADC_START_STOP);
> +
> + /* Wait for the first conversion to complete. */
> + udelay(1250);
> +}
> +
> +#define RCAR_GYROADC_CHAN(_idx, _chan_type, _realbits) { \
> + .type = (_chan_type), \
_chan_type is IIO_VOLTAGE always?
> + .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), \
> + .scan_index = (_idx), \
no buffered mode yet, so strictly no need for a scan_index and scan_type
> + .scan_type = { \
> + .sign = 'u', \
> + .realbits = (_realbits), \
> + .storagebits = 16, \
> + }, \
> +}
> +
> +static const struct iio_chan_spec rcar_gyroadc_iio_channels_1[] = {
> + RCAR_GYROADC_CHAN(0, IIO_VOLTAGE, 12),
> + RCAR_GYROADC_CHAN(1, IIO_VOLTAGE, 12),
> + RCAR_GYROADC_CHAN(2, IIO_VOLTAGE, 12),
> + RCAR_GYROADC_CHAN(3, IIO_VOLTAGE, 12),
> +};
> +
> +static const struct iio_chan_spec rcar_gyroadc_iio_channels_2[] = {
> + RCAR_GYROADC_CHAN(0, IIO_VOLTAGE, 15),
> + RCAR_GYROADC_CHAN(1, IIO_VOLTAGE, 15),
> + RCAR_GYROADC_CHAN(2, IIO_VOLTAGE, 15),
> + RCAR_GYROADC_CHAN(3, IIO_VOLTAGE, 15),
> + RCAR_GYROADC_CHAN(4, IIO_VOLTAGE, 15),
> + RCAR_GYROADC_CHAN(5, IIO_VOLTAGE, 15),
> + RCAR_GYROADC_CHAN(6, IIO_VOLTAGE, 15),
> + RCAR_GYROADC_CHAN(7, IIO_VOLTAGE, 15),
> +};
> +
> +/*
> + * NOTE: The data we receive in mode 3 from MAX1162 have MSByte = 0,
> + * therefore we only use 16bit realbits here instead of 24.
> + */
> +static const struct iio_chan_spec rcar_gyroadc_iio_channels_3[] = {
> + RCAR_GYROADC_CHAN(0, IIO_VOLTAGE, 16),
> + RCAR_GYROADC_CHAN(1, IIO_VOLTAGE, 16),
> + RCAR_GYROADC_CHAN(2, IIO_VOLTAGE, 16),
> + RCAR_GYROADC_CHAN(3, IIO_VOLTAGE, 16),
> + RCAR_GYROADC_CHAN(4, IIO_VOLTAGE, 16),
> + RCAR_GYROADC_CHAN(5, IIO_VOLTAGE, 16),
> + RCAR_GYROADC_CHAN(6, IIO_VOLTAGE, 16),
> + RCAR_GYROADC_CHAN(7, IIO_VOLTAGE, 16),
> +};
> +
> +static int rcar_gyroadc_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + struct rcar_gyroadc *priv = iio_priv(indio_dev);
> + unsigned int datareg = RCAR_GYROADC_REALTIME_DATA(chan->channel);
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + if (chan->type != IIO_VOLTAGE)
> + return -EINVAL;
> +
> + if (iio_buffer_enabled(indio_dev))
> + return -EBUSY;
use iio_device_claim_direct_mode()
> +
> + *val = readl(priv->regs + datareg);
> + *val &= BIT(chan->scan_type.realbits) - 1;
> +
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_SCALE:
> + *val = 0;
> + *val2 = (priv->vref_uv[chan->channel] * 1000) / 0x10000;
> + return IIO_VAL_INT_PLUS_NANO;
> + case IIO_CHAN_INFO_SAMP_FREQ:
> + *val = RCAR_GYROADC_SAMPLE_RATE;
> + *val2 = 0;
*val2 = 0 not needed
> + return IIO_VAL_INT;
> + default:
> + break;
return -EINVAL;
here directly
> + }
> +
> + return -EINVAL;
> +}
> +
> +static int rcar_gyroadc_reg_access(struct iio_dev *indio_dev,
> + unsigned int reg, unsigned int writeval,
> + unsigned int *readval)
> +{
> + struct rcar_gyroadc *priv = iio_priv(indio_dev);
> + unsigned int maxreg = RCAR_GYROADC_INTENR;
> +
> + if (readval == NULL)
> + return -EINVAL;
> +
> + if (reg % 4)
> + return -EINVAL;
> +
> + /* Handle the V2H case with missing interrupt block. */
> + if (priv->model == RCAR_GYROADC_MODEL_R8A7792)
> + maxreg = RCAR_GYROADC_FIFO_STATUS;
> +
> + if (reg > maxreg)
> + return -EINVAL;
> +
> + *readval = readl(priv->regs + reg);
> +
> + return 0;
> +}
> +
> +static const struct iio_info rcar_gyroadc_iio_info = {
> + .driver_module = THIS_MODULE,
> + .read_raw = rcar_gyroadc_read_raw,
> + .debugfs_reg_access = rcar_gyroadc_reg_access,
> +};
> +
> +static const struct of_device_id rcar_gyroadc_match[] = {
> + {
> + /* RCar Gen2 compatible GyroADC */
> + .compatible = "renesas,rcar-gyroadc",
> + .data = (void *)RCAR_GYROADC_MODEL_DEFAULT,
> + }, {
> + /* RCar V2H specialty without interrupt registers. */
> + .compatible = "renesas,rcar-gyroadc-r8a7792",
> + .data = (void *)RCAR_GYROADC_MODEL_R8A7792,
> + }, {
> + /* sentinel */
> + }
> +};
> +
> +MODULE_DEVICE_TABLE(of, rcar_gyroadc_match);
> +
> +static int rcar_gyroadc_probe(struct platform_device *pdev)
> +{
> + const struct of_device_id *of_id =
> + of_match_device(rcar_gyroadc_match, &pdev->dev);
> + struct device *dev = &pdev->dev;
> + struct rcar_gyroadc *priv;
> + struct iio_dev *indio_dev;
> + struct resource *mem;
> + int ret, mode;
> +
> + indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
> + if (!indio_dev) {
> + dev_err(dev, "Failed to allocate IIO device.\n");
> + return -ENOMEM;
> + }
> +
> + priv = iio_priv(indio_dev);
> + priv->dev = dev;
> +
> + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + priv->regs = devm_ioremap_resource(dev, mem);
> + if (IS_ERR(priv->regs))
> + return PTR_ERR(priv->regs);
> +
> + priv->fclk = devm_clk_get(dev, "fck");
> + if (IS_ERR(priv->fclk)) {
> + ret = PTR_ERR(priv->fclk);
> + dev_err(dev, "Failed to get FCK clock (ret=%i)\n", ret);
> + return ret;
> + }
> +
> + priv->clk = devm_clk_get(dev, "if");
> + if (IS_ERR(priv->clk)) {
> + ret = PTR_ERR(priv->clk);
> + dev_err(dev, "Failed to get IF clock (ret=%i)\n", ret);
> + return ret;
> + }
> +
> + ret = of_property_read_u32(pdev->dev.of_node, "renesas,gyroadc-mode",
> + &mode);
> + if (ret || (mode < 1) || (mode > 3)) {
the mode check could be a simple 'else' below?
> + dev_err(dev, "Failed to get GyroADC mode (ret=%i)\n", ret);
> + return ret;
> + }
> +
> + if (mode == 1)
> + priv->mode = RCAR_GYROADC_MODE_SELECT_1_MB88101A;
> + else if (mode == 2)
> + priv->mode = RCAR_GYROADC_MODE_SELECT_2_ADCS7476;
> + else if (mode == 3)
> + priv->mode = RCAR_GYROADC_MODE_SELECT_3_MAX1162;
> +
> + of_property_read_u32_array(pdev->dev.of_node, "renesas,gyroadc-vref",
> + priv->vref_uv, (mode == 1) ? 4 : 8);
> +
> + priv->model = (enum rcar_gyroadc_model)of_id->data;
> +
> + platform_set_drvdata(pdev, indio_dev);
> +
> + indio_dev->name = dev_name(dev);
> + indio_dev->dev.parent = dev;
> + indio_dev->dev.of_node = pdev->dev.of_node;
> + indio_dev->info = &rcar_gyroadc_iio_info;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> + if (mode == 1) {
maybe do the mode differentiation only once, any with a switch?
> + indio_dev->channels = rcar_gyroadc_iio_channels_1;
> + indio_dev->num_channels =
> + ARRAY_SIZE(rcar_gyroadc_iio_channels_1);
> + } else if (mode == 2) {
> + indio_dev->channels = rcar_gyroadc_iio_channels_2;
> + indio_dev->num_channels =
> + ARRAY_SIZE(rcar_gyroadc_iio_channels_2);
> + } else if (mode == 3) {
> + indio_dev->channels = rcar_gyroadc_iio_channels_3;
> + indio_dev->num_channels =
> + ARRAY_SIZE(rcar_gyroadc_iio_channels_3);
> + }
> +
> + ret = clk_prepare_enable(priv->fclk);
> + if (ret) {
> + dev_err(dev, "Could not prepare or enable the FCK clock.\n");
> + return ret;
> + }
> +
> + ret = clk_prepare_enable(priv->clk);
> + if (ret) {
> + dev_err(dev, "Could not prepare or enable the IF clock.\n");
> + goto error_clk_if_enable;
> + }
> +
> + rcar_gyroadc_hw_init(priv);
> +
> + ret = iio_device_register(indio_dev);
> + if (ret) {
> + dev_err(dev, "Couldn't register IIO device.\n");
> + goto error_iio_device_register;
> + }
> +
> + return 0;
> +
> +error_iio_device_register:
> + clk_disable_unprepare(priv->clk);
> +error_clk_if_enable:
> + clk_disable_unprepare(priv->fclk);
> + return ret;
> +}
> +
> +static int rcar_gyroadc_remove(struct platform_device *pdev)
> +{
> + struct iio_dev *indio_dev = platform_get_drvdata(pdev);
> + struct rcar_gyroadc *priv = iio_priv(indio_dev);
> +
> + /* Stop sampling */
> + writel(0, priv->regs + RCAR_GYROADC_START_STOP);
> +
> + iio_device_unregister(indio_dev);
> + clk_disable_unprepare(priv->clk);
> + clk_disable_unprepare(priv->fclk);
> +
> + return 0;
> +}
> +
> +static struct platform_driver rcar_gyroadc_driver = {
> + .probe = rcar_gyroadc_probe,
> + .remove = rcar_gyroadc_remove,
> + .driver = {
> + .name = "rcar-gyroadc",
> + .of_match_table = rcar_gyroadc_match,
> + },
> +};
> +
> +module_platform_driver(rcar_gyroadc_driver);
> +
> +MODULE_AUTHOR("Marek Vasut <marek.vasut@xxxxxxxxx>");
> +MODULE_DESCRIPTION("Renesas RCAR GyroADC driver");
> +MODULE_LICENSE("GPL v2");
>
--
Peter Meerwald-Stadler
+43-664-2444418 (mobile)
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