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.
Signed-off-by: Marek Vasut <marek.vasut@xxxxxxxxx>
Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Cc: Simon Horman <horms+renesas@xxxxxxxxxxxx>
Cc: Jonathan Cameron <jic23@xxxxxxxxxx>
Cc: linux-renesas-soc@xxxxxxxxxxxxxxx
---
V2: - Spelling fixes
- Rename the driver source file to rcar-gyroadc
- Rework the channel sample width handling
- Use iio_device_claim_mode_direct()
- Rename "renesas,rcar-gyroadc" to "renesas,r8a7791-gyroadc" and
rename "renesas,rcar-gyroadc-r8a7792" to "renesas,r8a7792-gyroadc"
to match the new naming scheme (WARNING: scif uses the old one!)
- Switch to using regulators for channel voltage reference, add new
properties renesas,gyroadc-vref-chN-supply for N in 0..7
- Handle vref regulators as optional to, make channels without
vref regulator return EINVAL on read.
- Fix module license to GPL
- Drop interrupt.h include
- Rename clk to iclk
- Rename RCar to R-Car
- Rework the invalid mode handling
- Don't print error message on EPROBE_DEFER
- Drop fclk handling, use runtime PM for that instead
V3: - More R-Car spelling fixes
- Flip checks for V2H, since that's the only one that has
interrupt registers
- Replace if-else statement with switch statement in init_mode
- Use unsigned types where applicable
- Rework timing calculation slightly to drop if-else block
- Use DIV_ROUND_CLOSEST
V4: - Add renesas,rcar-gyroadc fallback compatible string into the bindings
- Rework the ADC bindings to use per-channel subdevs
- Support more compatible ADC chips
V5: - Reword the DT bindings, improve the description of the modes
- Improve the description in Kconfig
- Implement special DT bindings for the MB88101A 4-channel ADC and
add special handling for this chip into the driver.
- Add missing ADC stop on failure, wrap it into a function
- Fail hard in case the DT properties are incorrect or missing
- Fix reporting of scale, so that channel * scale value is in mV
- Use fractional scale instead of int plus nano
- Use pm_runtime to disable the sampling 2 seconds after last used
---
.../bindings/iio/adc/renesas,gyroadc.txt | 93 +++
MAINTAINERS | 6 +
drivers/iio/adc/Kconfig | 13 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/rcar-gyroadc.c | 629 +++++++++++++++++++++
5 files changed, 742 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/adc/renesas,gyroadc.txt
create mode 100644 drivers/iio/adc/rcar-gyroadc.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 000000000000..081947367135
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/renesas,gyroadc.txt
@@ -0,0 +1,93 @@
+* Renesas RCar GyroADC device driver
+
+Required properties:
+- compatible: Should be "renesas,<chip>-gyroadc", "renesas,rcar-gyroadc".
+ Use "renesas,r8a7792-gyroadc" for a GyroADC with 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" is the GyroADC block
+ clock, the "if" is the interface clock.
+- power-domains: Must contain a reference to the PM domain, if available.
+- #address-cells: Should be <1> (setting for the subnodes) for all ADCs
+ except for "fujitsu,mb88101a". Should be <0> (setting for
+ only subnode) for "fujitsu,mb88101a".
+- #size-cells: Should be <0> (setting for the subnodes)
+
+Sub-nodes:
+Optionally you can define subnodes which select the connected ADC type and
+reference voltage for the GyroADC channels.
+
+Required properties for subnodes:
+- compatible: Should be either of:
+ "fujitsu,mb88101a"
+ - Fujitsu MB88101A compatible mode,
+ 12bit sampling, up to 4 channels can be sampled in
+ round-robin fashion. One Fujitsu chip supplies four
+ GyroADC channels with data as it contains four ADCs
+ on the chip and thus for 4-channel operation, single
+ MB88101A is required. The Cx chipselect lines of the
+ MB88101A connect directly to two CHS lines of the
+ GyroADC, no demuxer is required. The data out line
+ of each MB88101A connects to a shared input pin of
+ the GyroADC.
+ "ti,adcs7476" or "ti,adc121" or "adi,ad7476"
+ - TI ADCS7476 / TI ADC121 / ADI AD7476 compatible mode,
+ 15bit sampling, up to 8 channels can be sampled in
+ round-robin fashion. One TI/ADI chip supplies single
+ ADC channel with data, thus for 8-channel operation,
+ 8 chips are required. A 3:8 chipselect demuxer is
+ required to connect the nCS line of the TI/ADI chips
+ to the GyroADC, while MISO line of each TI/ADI ADC
+ connects to a shared input pin of the GyroADC.
+ "maxim,max1162" or "maxim,max11100"
+ - Maxim MAX1162 / Maxim MAX11100 compatible mode,
+ 16bit sampling, up to 8 channels can be sampled in
+ round-robin fashion. One Maxim chip supplies single
+ ADC channel with data, thus for 8-channel operation,
+ 8 chips are required. A 3:8 chipselect demuxer is
+ required to connect the nCS line of the MAX chips
+ to the GyroADC, while MISO line of each Maxim ADC
+ connects to a shared input pin of the GyroADC.
+- reg: Should be the number of the analog input. Should be present
+ for all ADCs except "fujitsu,mb88101a".
+- vref-supply: Reference to the channel reference voltage regulator.
+
+Example:
+ vref_max1162: regulator-vref-max1162 {
+ compatible = "regulator-fixed";
+
+ regulator-name = "MAX1162 Vref";
+ regulator-min-microvolt = <4096000>;
+ regulator-max-microvolt = <4096000>;
+ };
+
+ &adc {
+ compatible = "renesas,r8a7791-gyroadc", "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";
+
+ status = "okay";
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ adc@0 {
+ reg = <0>;
+ compatible = "maxim,max1162";
+ vref-supply = <&vref_max1162>;
+ };
+
+ adc@1 {
+ reg = <1>;
+ compatible = "maxim,max1162";
+ vref-supply = <&vref_max1162>;
+ };
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index 890fc9e3c191..498e8a755eb6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10276,6 +10276,12 @@ L: linux-renesas-soc@xxxxxxxxxxxxxxx
F: drivers/net/ethernet/renesas/
F: include/linux/sh_eth.h
+RENESAS R-CAR 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 99c051490eff..2fbc11f42740 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -408,6 +408,19 @@ 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 R-Car GyroADC driver"
+ depends on ARCH_RCAR_GEN2 || (ARM && COMPILE_TEST)
+ help
+ Say yes here to build support for the GyroADC found in Renesas
+ R-Car Gen2 SoCs. This block is a simple SPI offload engine for
+ reading data out of attached compatible ADCs in a round-robin
+ fashion. Up to 4 or 8 ADC channels are supported by this block,
+ depending on which ADCs are attached.
+
+ To compile this driver as a module, choose M here: the
+ module will be called rcar-gyroadc.
+
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 7a40c04c311f..13db7c2bffc8 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-$(CONFIG_RCAR_GYRO_ADC) += rcar-gyroadc.o
obj-$(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-gyroadc.c b/drivers/iio/adc/rcar-gyroadc.c
new file mode 100644
index 000000000000..2f67416fd396
--- /dev/null
+++ b/drivers/iio/adc/rcar-gyroadc.c
@@ -0,0 +1,629 @@
+/*
+ * Renesas R-Car 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/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/pm_runtime.h>
+
+#include <linux/iio/iio.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)))
+#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 */
+
+#define RCAR_GYROADC_RUNTIME_PM_DELAY_MS 2000
+
+enum rcar_gyroadc_model {
+ RCAR_GYROADC_MODEL_DEFAULT,
+ RCAR_GYROADC_MODEL_R8A7792,
+};
+
+struct rcar_gyroadc {
+ struct device *dev;
+ void __iomem *regs;
+ struct clk *iclk;
+ struct regulator *vref[8];
+ unsigned int num_channels;
+ enum rcar_gyroadc_model model;
+ unsigned int mode;
+ unsigned int sample_width;
+};
+
+static void rcar_gyroadc_hw_init(struct rcar_gyroadc *priv)
+{
+ const unsigned long clk_mhz = clk_get_rate(priv->iclk) / 1000000;
+ const unsigned long clk_mul =
+ (priv->mode == RCAR_GYROADC_MODE_SELECT_1_MB88101A) ? 10 : 5;
+ unsigned long clk_len = clk_mhz * clk_mul;
+
+ /*
+ * According to the R-Car Gen2 datasheet Rev. 1.01, Sept 08 2014,
+ * page 77-7, clock length must be even number. If it's odd number,
+ * add one.
+ */
+ if (clk_len & 1)
+ clk_len++;
+
+ /* Stop the GyroADC. */
+ writel(0, priv->regs + RCAR_GYROADC_START_STOP);
+
+ /* Disable IRQ 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);
+ writel(clk_len, priv->regs + RCAR_GYROADC_CLOCK_LENGTH);
+ writel(clk_mhz * 1250, priv->regs + RCAR_GYROADC_1_25MS_LENGTH);
+}
+
+static void rcar_gyroadc_hw_start(struct rcar_gyroadc *priv)
+{
+ /* Start sampling. */
+ writel(RCAR_GYROADC_START_STOP_START,
+ priv->regs + RCAR_GYROADC_START_STOP);
+
+ /*
+ * Wait for the first conversion to complete. This is longer than
+ * the 1.25 mS in the datasheet because 1.25 mS is not enough for
+ * the hardware to deliver the first sample and the hardware does
+ * then return zeroes instead of valid data.
+ */
+ mdelay(3);
+}
+
+static void rcar_gyroadc_hw_stop(struct rcar_gyroadc *priv)
+{
+ /* Stop the GyroADC. */
+ writel(0, priv->regs + RCAR_GYROADC_START_STOP);
+}
+
+#define RCAR_GYROADC_CHAN(_idx) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = (_idx), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+}
+
+static const struct iio_chan_spec rcar_gyroadc_iio_channels_1[] = {
+ RCAR_GYROADC_CHAN(0),
+ RCAR_GYROADC_CHAN(1),
+ RCAR_GYROADC_CHAN(2),
+ RCAR_GYROADC_CHAN(3),
+};
+
+static const struct iio_chan_spec rcar_gyroadc_iio_channels_2[] = {
+ RCAR_GYROADC_CHAN(0),
+ RCAR_GYROADC_CHAN(1),
+ RCAR_GYROADC_CHAN(2),
+ RCAR_GYROADC_CHAN(3),
+ RCAR_GYROADC_CHAN(4),
+ RCAR_GYROADC_CHAN(5),
+ RCAR_GYROADC_CHAN(6),
+ RCAR_GYROADC_CHAN(7),
+};
+
+static const struct iio_chan_spec rcar_gyroadc_iio_channels_3[] = {
+ RCAR_GYROADC_CHAN(0),
+ RCAR_GYROADC_CHAN(1),
+ RCAR_GYROADC_CHAN(2),
+ RCAR_GYROADC_CHAN(3),
+ RCAR_GYROADC_CHAN(4),
+ RCAR_GYROADC_CHAN(5),
+ RCAR_GYROADC_CHAN(6),
+ RCAR_GYROADC_CHAN(7),
+};
+
+static int rcar_gyroadc_set_power(struct rcar_gyroadc *priv, bool on)
+{
+ struct device *dev = priv->dev;
+ int ret;
+
+ if (on) {
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0)
+ pm_runtime_put_noidle(dev);
+ } else {
+ pm_runtime_mark_last_busy(dev);
+ ret = pm_runtime_put_autosuspend(dev);
+ }
+
+ return ret;
+}
+
+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);
+ struct regulator *consumer;
+ unsigned int datareg = RCAR_GYROADC_REALTIME_DATA(chan->channel);
+ unsigned int vref;
+ int ret;
+
+ /*
+ * MB88101 is special in that it has only single regulator for
+ * all four channels.
+ */
+ if (priv->mode == RCAR_GYROADC_MODE_SELECT_1_MB88101A)
+ consumer = priv->vref[0];
+ else
+ consumer = priv->vref[chan->channel];
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (chan->type != IIO_VOLTAGE)
+ return -EINVAL;
+
+ /* Channel not connected. */
+ if (!consumer)
+ return -EINVAL;
+
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+
+ ret = rcar_gyroadc_set_power(priv, true);
+ if (ret < 0) {
+ iio_device_release_direct_mode(indio_dev);
+ return ret;
+ }
+
+ *val = readl(priv->regs + datareg);
+ *val &= BIT(priv->sample_width) - 1;
+
+ ret = rcar_gyroadc_set_power(priv, false);
+ iio_device_release_direct_mode(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ /* Channel not connected. */
+ if (!consumer)
+ return -EINVAL;
+
+ vref = regulator_get_voltage(consumer);
+ *val = vref / 1000;
+ *val2 = 1 << priv->sample_width;
+
+ return IIO_VAL_FRACTIONAL;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = RCAR_GYROADC_SAMPLE_RATE;
+
+ return IIO_VAL_INT;
+ default:
+ 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_FIFO_STATUS;
+
+ if (readval == NULL)
+ return -EINVAL;
+
+ if (reg % 4)
+ return -EINVAL;
+
+ /* Handle the V2H case with extra interrupt block. */
+ if (priv->model == RCAR_GYROADC_MODEL_R8A7792)
+ maxreg = RCAR_GYROADC_INTENR;
+
+ 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[] = {
+ {
+ /* R-Car compatible GyroADC */
+ .compatible = "renesas,rcar-gyroadc",
+ .data = (void *)RCAR_GYROADC_MODEL_DEFAULT,
+ }, {
+ /* R-Car V2H specialty with interrupt registers. */
+ .compatible = "renesas,r8a7792-gyroadc",
+ .data = (void *)RCAR_GYROADC_MODEL_R8A7792,
+ }, {
+ /* sentinel */
+ }
+};
+
+MODULE_DEVICE_TABLE(of, rcar_gyroadc_match);
+
+static const struct of_device_id rcar_gyroadc_child_match[] = {
+ /* Mode 1 ADCs */
+ {
+ .compatible = "fujitsu,mb88101a",
+ .data = (void *)RCAR_GYROADC_MODE_SELECT_1_MB88101A,
+ },
+ /* Mode 2 ADCs */
+ {
+ .compatible = "ti,adcs7476",
+ .data = (void *)RCAR_GYROADC_MODE_SELECT_2_ADCS7476,
+ }, {
+ .compatible = "ti,adc121",
+ .data = (void *)RCAR_GYROADC_MODE_SELECT_2_ADCS7476,
+ }, {
+ .compatible = "adi,ad7476",
+ .data = (void *)RCAR_GYROADC_MODE_SELECT_2_ADCS7476,
+ },
+ /* Mode 3 ADCs */
+ {
+ .compatible = "maxim,max1162",
+ .data = (void *)RCAR_GYROADC_MODE_SELECT_3_MAX1162,
+ }, {
+ .compatible = "maxim,max11100",
+ .data = (void *)RCAR_GYROADC_MODE_SELECT_3_MAX1162,
+ },
+ { /* sentinel */ }
+};
+
+static int rcar_gyroadc_parse_subdevs(struct iio_dev *indio_dev)
+{
+ const struct of_device_id *of_id;
+ const struct iio_chan_spec *channels;
+ struct rcar_gyroadc *priv = iio_priv(indio_dev);
+ struct device *dev = priv->dev;
+ struct device_node *np = dev->of_node;
+ struct device_node *child;
+ struct regulator *vref;
+ unsigned int reg;
+ unsigned int adcmode, childmode;
+ unsigned int sample_width;
+ unsigned int num_channels;
+ int ret, first = 1;
+
+ for_each_child_of_node(np, child) {
+ of_id = of_match_node(rcar_gyroadc_child_match, child);
+ if (!of_id) {
+ dev_err(dev, "Ignoring unsupported ADC \"%s\".",
+ child->name);
+ continue;
+ }
+
+ childmode = (unsigned int)of_id->data;
+ switch (childmode) {
+ case RCAR_GYROADC_MODE_SELECT_1_MB88101A:
+ sample_width = 12;
+ channels = rcar_gyroadc_iio_channels_1;
+ num_channels = ARRAY_SIZE(rcar_gyroadc_iio_channels_1);
+ break;
+ case RCAR_GYROADC_MODE_SELECT_2_ADCS7476:
+ sample_width = 15;
+ channels = rcar_gyroadc_iio_channels_2;
+ num_channels = ARRAY_SIZE(rcar_gyroadc_iio_channels_2);
+ break;
+ case RCAR_GYROADC_MODE_SELECT_3_MAX1162:
+ sample_width = 16;
+ channels = rcar_gyroadc_iio_channels_3;
+ num_channels = ARRAY_SIZE(rcar_gyroadc_iio_channels_3);
+ break;
+ }
+
+ /*
+ * MB88101 is special in that it's only a single chip taking
+ * up all the CHS lines. Thus, the DT binding is also special
+ * and has no reg property. If we run into such ADC, handle
+ * it here.
+ */
+ if (childmode == RCAR_GYROADC_MODE_SELECT_1_MB88101A) {
+ reg = 0;
+ } else {
+ ret = of_property_read_u32(child, "reg", ®);
+ if (ret) {
+ dev_err(dev,
+ "Failed to get child reg property of ADC \"%s\".\n",
+ child->name);
+ return ret;
+ }
+
+ /* Channel number is too high. */
+ if (reg >= num_channels) {
+ dev_err(dev,
+ "Only %i channels supported with %s, but reg = <%i>.\n",
+ num_channels, child->name, reg);
+ return ret;
+ }
+ }
+
+ /* Child node selected different mode than the rest. */
+ if (!first && (adcmode != childmode)) {
+ dev_err(dev,
+ "Channel %i uses different ADC mode than the rest.\n",
+ reg);
+ return ret;
+ }
+
+ /* Channel is valid, grab the regulator. */
+ dev->of_node = child;
+ vref = devm_regulator_get(dev, "vref");
+ dev->of_node = np;
+ if (IS_ERR(vref)) {
+ dev_dbg(dev, "Channel %i 'vref' supply not connected.\n",
+ reg);
+ return PTR_ERR(vref);
+ }
+
+ priv->vref[reg] = vref;
+
+ if (!first)
+ continue;
+
+ /* First child node which passed sanity tests. */
+ adcmode = childmode;
+ first = 0;
+
+ priv->num_channels = num_channels;
+ priv->mode = childmode;
+ priv->sample_width = sample_width;
+
+ indio_dev->channels = channels;
+ indio_dev->num_channels = num_channels;
+
+ /*
+ * MB88101 is special and we only have one such device
+ * attached to the GyroADC at a time, so if we found it,
+ * we can stop parsing here.
+ */
+ if (childmode == RCAR_GYROADC_MODE_SELECT_1_MB88101A)
+ break;
+ }
+
+ if (first) {
+ dev_err(dev, "No valid ADC channels found, aborting.\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void rcar_gyroadc_deinit_supplies(struct iio_dev *indio_dev)
+{
+ struct rcar_gyroadc *priv = iio_priv(indio_dev);
+ unsigned int i;
+
+ for (i = 0; i < priv->num_channels; i++) {
+ if (!priv->vref[i])
+ continue;
+
+ regulator_disable(priv->vref[i]);
+ }
+}
+
+static int rcar_gyroadc_init_supplies(struct iio_dev *indio_dev)
+{
+ struct rcar_gyroadc *priv = iio_priv(indio_dev);
+ struct device *dev = priv->dev;
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < priv->num_channels; i++) {
+ if (!priv->vref[i])
+ continue;
+
+ ret = regulator_enable(priv->vref[i]);
+ if (ret) {
+ dev_err(dev, "Failed to enable regulator %i (ret=%i)\n",
+ i, ret);
+ goto err;
+ }
+ }
+
+ return 0;
+
+err:
+ rcar_gyroadc_deinit_supplies(indio_dev);
+ return ret;
+}
+
+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;
+
+ 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->iclk = devm_clk_get(dev, "if");
+ if (IS_ERR(priv->iclk)) {
+ ret = PTR_ERR(priv->iclk);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "Failed to get IF clock (ret=%i)\n", ret);
+ return ret;
+ }
+
+ ret = rcar_gyroadc_parse_subdevs(indio_dev);
+ if (ret)
+ return ret;
+
+ ret = rcar_gyroadc_init_supplies(indio_dev);
+ if (ret)
+ return ret;
+
+ 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;
+
+ ret = clk_prepare_enable(priv->iclk);
+ if (ret) {
+ dev_err(dev, "Could not prepare or enable the IF clock.\n");
+ goto err_clk_if_enable;
+ }
+
+ pm_runtime_set_autosuspend_delay(dev, RCAR_GYROADC_RUNTIME_PM_DELAY_MS);
+ pm_runtime_use_autosuspend(dev);
+ pm_runtime_enable(dev);
+
+ pm_runtime_get_sync(dev);
+ rcar_gyroadc_hw_init(priv);
+ rcar_gyroadc_hw_start(priv);
+
+ ret = iio_device_register(indio_dev);
+ if (ret) {
+ dev_err(dev, "Couldn't register IIO device.\n");
+ goto err_iio_device_register;
+ }
+
+ pm_runtime_put_sync(dev);
+
+ return 0;
+
+err_iio_device_register:
+ rcar_gyroadc_hw_stop(priv);
+ pm_runtime_put_sync(dev);
+ pm_runtime_disable(dev);
+ pm_runtime_set_suspended(dev);
+ clk_disable_unprepare(priv->iclk);
+err_clk_if_enable:
+ rcar_gyroadc_deinit_supplies(indio_dev);
+
+ 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);
+ struct device *dev = priv->dev;
+
+ iio_device_unregister(indio_dev);
+ pm_runtime_get_sync(dev);
+ rcar_gyroadc_hw_stop(priv);
+ pm_runtime_put_sync(dev);
+ pm_runtime_disable(dev);
+ pm_runtime_set_suspended(dev);
+ clk_disable_unprepare(priv->iclk);
+ rcar_gyroadc_deinit_supplies(indio_dev);
+
+ return 0;
+}
+
+#if defined(CONFIG_PM)
+static int rcar_gyroadc_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct rcar_gyroadc *priv = iio_priv(indio_dev);
+
+ rcar_gyroadc_hw_stop(priv);
+
+ return 0;
+}
+
+static int rcar_gyroadc_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct rcar_gyroadc *priv = iio_priv(indio_dev);
+
+ rcar_gyroadc_hw_start(priv);
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops rcar_gyroadc_pm_ops = {
+ SET_RUNTIME_PM_OPS(rcar_gyroadc_suspend, rcar_gyroadc_resume, NULL)
+};
+
+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,
+ .pm = &rcar_gyroadc_pm_ops,
+ },
+};
+
+module_platform_driver(rcar_gyroadc_driver);
+
+MODULE_AUTHOR("Marek Vasut <marek.vasut@xxxxxxxxx>");
+MODULE_DESCRIPTION("Renesas R-Car GyroADC driver");
+MODULE_LICENSE("GPL");
--
2.11.0
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