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>
---
.../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
+ clock, the "if" are the interface clock.
+ power-domains = <&sysc R8A7791_PD_ALWAYS_ON>;
+- 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
+ 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.
+
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)))
+#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), \
+ .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), \
+ .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;
+
+ *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;
+ return IIO_VAL_INT;
+ default:
+ break;
+ }
+
+ 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)) {
+ 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) {
+ 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");
--
2.10.2
--
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