[PATCH v3 2/3] iio: Add driver for Broadcom iproc-static-adc
From: Raveendra Padasalagi
Date: Wed Jun 22 2016 - 02:12:05 EST
This patch adds basic driver implementation for Broadcom's
static adc controller used in iProc SoC's family.
Signed-off-by: Raveendra Padasalagi <raveendra.padasalagi@xxxxxxxxxxxx>
Reviewed-by: Ray Jui <ray.jui@xxxxxxxxxxxx>
Reviewed-by: Scott Branden <scott.branden@xxxxxxxxxxxx>
---
drivers/iio/adc/Kconfig | 12 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/bcm_iproc_adc.c | 648 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 661 insertions(+)
create mode 100644 drivers/iio/adc/bcm_iproc_adc.c
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 25378c5..1de31bd 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -153,6 +153,18 @@ config AXP288_ADC
To compile this driver as a module, choose M here: the module will be
called axp288_adc.
+config BCM_IPROC_ADC
+ tristate "Broadcom IPROC ADC driver"
+ depends on ARCH_BCM_IPROC || COMPILE_TEST
+ depends on MFD_SYSCON
+ default ARCH_BCM_CYGNUS
+ help
+ Say Y here if you want to add support for the Broadcom static
+ ADC driver.
+
+ Broadcom iProc ADC driver. Broadcom iProc ADC controller has 8
+ channels. The driver allows the user to read voltage values.
+
config BERLIN2_ADC
tristate "Marvell Berlin2 ADC driver"
depends on ARCH_BERLIN
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 38638d4..0ba0d50 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -16,6 +16,7 @@ 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-$(CONFIG_BCM_IPROC_ADC) += bcm_iproc_adc.o
obj-$(CONFIG_BERLIN2_ADC) += berlin2-adc.o
obj-$(CONFIG_CC10001_ADC) += cc10001_adc.o
obj-$(CONFIG_DA9150_GPADC) += da9150-gpadc.o
diff --git a/drivers/iio/adc/bcm_iproc_adc.c b/drivers/iio/adc/bcm_iproc_adc.c
new file mode 100644
index 0000000..e10f6ce
--- /dev/null
+++ b/drivers/iio/adc/bcm_iproc_adc.c
@@ -0,0 +1,648 @@
+/*
+ * Copyright 2016 Broadcom
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation (the "GPL").
+ *
+ * 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 version 2 (GPLv2) for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 (GPLv2) along with this source code.
+ */
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+
+#include <linux/iio/iio.h>
+
+/* Below Register's are common to IPROC ADC and Touchscreen IP */
+#define IPROC_REGCTL1 0x00
+#define IPROC_REGCTL2 0x04
+#define IPROC_INTERRUPT_THRES 0x08
+#define IPROC_INTERRUPT_MASK 0x0c
+#define IPROC_INTERRUPT_STATUS 0x10
+#define IPROC_ANALOG_CONTROL 0x1c
+#define IPROC_CONTROLLER_STATUS 0x14
+#define IPROC_AUX_DATA 0x20
+#define IPROC_SOFT_BYPASS_CONTROL 0x38
+#define IPROC_SOFT_BYPASS_DATA 0x3C
+
+/* IPROC ADC Channel register offsets */
+#define IPROC_ADC_CHANNEL_REGCTL1 0x800
+#define IPROC_ADC_CHANNEL_REGCTL2 0x804
+#define IPROC_ADC_CHANNEL_STATUS 0x808
+#define IPROC_ADC_CHANNEL_INTERRUPT_STATUS 0x80c
+#define IPROC_ADC_CHANNEL_INTERRUPT_MASK 0x810
+#define IPROC_ADC_CHANNEL_DATA 0x814
+#define IPROC_ADC_CHANNEL_OFFSET 0x20
+
+/* Bit definitions for IPROC_REGCTL2 */
+#define IPROC_ADC_AUXIN_SCAN_ENA BIT(0)
+#define IPROC_ADC_PWR_LDO BIT(5)
+#define IPROC_ADC_PWR_ADC BIT(4)
+#define IPROC_ADC_PWR_BG BIT(3)
+#define IPROC_ADC_CONTROLLER_EN BIT(17)
+
+/* Bit definitions for IPROC_INTERRUPT_MASK and IPROC_INTERRUPT_STATUS */
+#define IPROC_ADC_AUXDATA_RDY_INTR BIT(3)
+#define IPROC_ADC_INTR 9
+#define IPROC_ADC_INTR_MASK (0xFF << IPROC_ADC_INTR)
+
+/* Bit definitions for IPROC_ANALOG_CONTROL */
+#define IPROC_ADC_CHANNEL_SEL 11
+#define IPROC_ADC_CHANNEL_SEL_MASK (0x7 << IPROC_ADC_CHANNEL_SEL)
+
+/* Bit definitions for IPROC_ADC_CHANNEL_REGCTL1 */
+#define IPROC_ADC_CHANNEL_ROUNDS 0x2
+#define IPROC_ADC_CHANNEL_ROUNDS_MASK (0x3F << IPROC_ADC_CHANNEL_ROUNDS)
+#define IPROC_ADC_CHANNEL_MODE 0x1
+#define IPROC_ADC_CHANNEL_MODE_MASK (0x1 << IPROC_ADC_CHANNEL_MODE)
+#define IPROC_ADC_CHANNEL_MODE_TDM 0x1
+#define IPROC_ADC_CHANNEL_MODE_SNAPSHOT 0x0
+#define IPROC_ADC_CHANNEL_ENABLE 0x0
+#define IPROC_ADC_CHANNEL_ENABLE_MASK 0x1
+
+/* Bit definitions for IPROC_ADC_CHANNEL_REGCTL2 */
+#define IPROC_ADC_CHANNEL_WATERMARK 0x0
+#define IPROC_ADC_CHANNEL_WATERMARK_MASK \
+ (0x3F << IPROC_ADC_CHANNEL_WATERMARK)
+
+#define IPROC_ADC_WATER_MARK_LEVEL 0x1
+
+/* Bit definitions for IPROC_ADC_CHANNEL_STATUS */
+#define IPROC_ADC_CHANNEL_DATA_LOST 0x0
+#define IPROC_ADC_CHANNEL_DATA_LOST_MASK \
+ (0x0 << IPROC_ADC_CHANNEL_DATA_LOST)
+#define IPROC_ADC_CHANNEL_VALID_ENTERIES 0x1
+#define IPROC_ADC_CHANNEL_VALID_ENTERIES_MASK \
+ (0xFF << IPROC_ADC_CHANNEL_VALID_ENTERIES)
+#define IPROC_ADC_CHANNEL_TOTAL_ENTERIES 0x9
+#define IPROC_ADC_CHANNEL_TOTAL_ENTERIES_MASK \
+ (0xFF << IPROC_ADC_CHANNEL_TOTAL_ENTERIES)
+
+/* Bit definitions for IPROC_ADC_CHANNEL_INTERRUPT_MASK */
+#define IPROC_ADC_CHANNEL_WTRMRK_INTR 0x0
+#define IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK \
+ (0x1 << IPROC_ADC_CHANNEL_WTRMRK_INTR)
+#define IPROC_ADC_CHANNEL_FULL_INTR 0x1
+#define IPROC_ADC_CHANNEL_FULL_INTR_MASK \
+ (0x1 << IPROC_ADC_IPROC_ADC_CHANNEL_FULL_INTR)
+#define IPROC_ADC_CHANNEL_EMPTY_INTR 0x2
+#define IPROC_ADC_CHANNEL_EMPTY_INTR_MASK \
+ (0x1 << IPROC_ADC_CHANNEL_EMPTY_INTR)
+
+#define IPROC_ADC_WATER_MARK_INTR_ENABLE 0x1
+
+/* Number of time to retry a set of the interrupt mask reg */
+#define IPROC_ADC_INTMASK_RETRY_ATTEMPTS 10
+
+#define IPROC_ADC_READ_TIMEOUT (HZ*2)
+
+#define iproc_adc_dbg_reg(dev, priv, reg) \
+do { \
+ u32 val; \
+ regmap_read(priv->regmap, reg, &val); \
+ dev_dbg(dev, "%20s= 0x%08x\n", #reg, val); \
+} while (0)
+
+struct iproc_adc_priv {
+ struct regmap *regmap;
+ struct clk *adc_clk;
+ struct mutex mutex;
+ int irqno;
+ int chan_val;
+ int chan_id;
+ struct completion completion;
+};
+
+static void iproc_adc_reg_dump(struct iio_dev *indio_dev)
+{
+ struct iproc_adc_priv *adc_priv;
+ struct device *dev = &indio_dev->dev;
+
+ adc_priv = iio_priv(indio_dev);
+
+ iproc_adc_dbg_reg(dev, adc_priv, IPROC_REGCTL1);
+ iproc_adc_dbg_reg(dev, adc_priv, IPROC_REGCTL2);
+ iproc_adc_dbg_reg(dev, adc_priv, IPROC_INTERRUPT_THRES);
+ iproc_adc_dbg_reg(dev, adc_priv, IPROC_INTERRUPT_MASK);
+ iproc_adc_dbg_reg(dev, adc_priv, IPROC_INTERRUPT_STATUS);
+ iproc_adc_dbg_reg(dev, adc_priv, IPROC_CONTROLLER_STATUS);
+ iproc_adc_dbg_reg(dev, adc_priv, IPROC_ANALOG_CONTROL);
+ iproc_adc_dbg_reg(dev, adc_priv, IPROC_AUX_DATA);
+ iproc_adc_dbg_reg(dev, adc_priv, IPROC_SOFT_BYPASS_CONTROL);
+ iproc_adc_dbg_reg(dev, adc_priv, IPROC_SOFT_BYPASS_DATA);
+}
+
+static irqreturn_t iproc_adc_interrupt_handler(int irq, void *data)
+{
+ u32 channel_intr_status;
+ u32 intr_status;
+ u32 intr_mask;
+ struct iio_dev *indio_dev = data;
+ struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
+
+ /*
+ * This interrupt is shared with the touchscreen driver.
+ * Make sure this interrupt is intended for us.
+ * Handle only ADC channel specific interrupts.
+ */
+ regmap_read(adc_priv->regmap, IPROC_INTERRUPT_STATUS, &intr_status);
+ regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &intr_mask);
+ intr_status = intr_status & intr_mask;
+ channel_intr_status = (intr_status & IPROC_ADC_INTR_MASK) >>
+ IPROC_ADC_INTR;
+ if (channel_intr_status)
+ return IRQ_WAKE_THREAD;
+
+ return IRQ_NONE;
+}
+
+static irqreturn_t iproc_adc_interrupt_thread(int irq, void *data)
+{
+ irqreturn_t retval = IRQ_NONE;
+ struct iproc_adc_priv *adc_priv;
+ struct iio_dev *indio_dev = data;
+ unsigned int valid_entries;
+ u32 intr_status;
+ u32 intr_channels;
+ u32 channel_status;
+ u32 ch_intr_status;
+
+ adc_priv = iio_priv(indio_dev);
+
+ regmap_read(adc_priv->regmap, IPROC_INTERRUPT_STATUS, &intr_status);
+ dev_dbg(&indio_dev->dev, "iproc_adc_interrupt_thread(),INTRPT_STS:%x\n",
+ intr_status);
+
+ intr_channels = (intr_status & IPROC_ADC_INTR_MASK) >> IPROC_ADC_INTR;
+ if (intr_channels) {
+ regmap_read(adc_priv->regmap,
+ IPROC_ADC_CHANNEL_INTERRUPT_STATUS +
+ IPROC_ADC_CHANNEL_OFFSET * adc_priv->chan_id,
+ &ch_intr_status);
+
+ if (ch_intr_status & IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK) {
+ regmap_read(adc_priv->regmap,
+ IPROC_ADC_CHANNEL_STATUS +
+ IPROC_ADC_CHANNEL_OFFSET *
+ adc_priv->chan_id,
+ &channel_status);
+
+ valid_entries = ((channel_status &
+ IPROC_ADC_CHANNEL_VALID_ENTERIES_MASK) >>
+ IPROC_ADC_CHANNEL_VALID_ENTERIES);
+ if (valid_entries >= 1) {
+ regmap_read(adc_priv->regmap,
+ IPROC_ADC_CHANNEL_DATA +
+ IPROC_ADC_CHANNEL_OFFSET *
+ adc_priv->chan_id,
+ &adc_priv->chan_val);
+ complete(&adc_priv->completion);
+ } else {
+ dev_err(&indio_dev->dev,
+ "No data rcvd on channel %d\n",
+ adc_priv->chan_id);
+ }
+ regmap_write(adc_priv->regmap,
+ IPROC_ADC_CHANNEL_INTERRUPT_MASK +
+ IPROC_ADC_CHANNEL_OFFSET *
+ adc_priv->chan_id,
+ (ch_intr_status &
+ ~(IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK)));
+ }
+ regmap_write(adc_priv->regmap,
+ IPROC_ADC_CHANNEL_INTERRUPT_STATUS +
+ IPROC_ADC_CHANNEL_OFFSET * adc_priv->chan_id,
+ ch_intr_status);
+ regmap_write(adc_priv->regmap, IPROC_INTERRUPT_STATUS,
+ intr_channels);
+ retval = IRQ_HANDLED;
+ }
+
+ return retval;
+}
+
+static int iproc_adc_do_read(struct iio_dev *indio_dev,
+ int channel,
+ u16 *p_adc_data)
+{
+ int read_len = 0;
+ u32 val;
+ u32 mask;
+ u32 val_check;
+ int failed_cnt = 0;
+ struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
+
+ mutex_lock(&adc_priv->mutex);
+
+ /*
+ * After a read is complete the ADC interrupts will be disabled so
+ * we can assume this section of code is safe from interrupts.
+ */
+ adc_priv->chan_val = -1;
+ adc_priv->chan_id = channel;
+
+ reinit_completion(&adc_priv->completion);
+ /* Clear any pending interrupt */
+ regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_STATUS,
+ IPROC_ADC_INTR_MASK | IPROC_ADC_AUXDATA_RDY_INTR,
+ ((0x0 << channel) << IPROC_ADC_INTR) |
+ IPROC_ADC_AUXDATA_RDY_INTR);
+
+ /* Configure channel for snapshot mode and enable */
+ val = (BIT(IPROC_ADC_CHANNEL_ROUNDS) |
+ (IPROC_ADC_CHANNEL_MODE_SNAPSHOT << IPROC_ADC_CHANNEL_MODE) |
+ (0x1 << IPROC_ADC_CHANNEL_ENABLE));
+
+ mask = IPROC_ADC_CHANNEL_ROUNDS_MASK | IPROC_ADC_CHANNEL_MODE_MASK |
+ IPROC_ADC_CHANNEL_ENABLE_MASK;
+ regmap_update_bits(adc_priv->regmap, (IPROC_ADC_CHANNEL_REGCTL1 +
+ IPROC_ADC_CHANNEL_OFFSET * channel),
+ mask, val);
+
+ /* Set the Watermark for a channel */
+ regmap_update_bits(adc_priv->regmap, (IPROC_ADC_CHANNEL_REGCTL2 +
+ IPROC_ADC_CHANNEL_OFFSET * channel),
+ IPROC_ADC_CHANNEL_WATERMARK_MASK,
+ 0x1);
+
+ /* Enable water mark interrupt */
+ regmap_update_bits(adc_priv->regmap, (IPROC_ADC_CHANNEL_INTERRUPT_MASK +
+ IPROC_ADC_CHANNEL_OFFSET *
+ channel),
+ IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK,
+ IPROC_ADC_WATER_MARK_INTR_ENABLE);
+ regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val);
+
+ /* Enable ADC interrupt for a channel */
+ val |= (BIT(channel) << IPROC_ADC_INTR);
+ regmap_write(adc_priv->regmap, IPROC_INTERRUPT_MASK, val);
+
+ /*
+ * There seems to be a very rare issue where writing to this register
+ * does not take effect. To work around the issue we will try multiple
+ * writes. In total we will spend about 10*10 = 100 us attempting this.
+ * Testing has shown that this may loop a few time, but we have never
+ * hit the full count.
+ */
+ regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val_check);
+ while (val_check != val) {
+ failed_cnt++;
+
+ if (failed_cnt > IPROC_ADC_INTMASK_RETRY_ATTEMPTS)
+ break;
+
+ udelay(10);
+ regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_MASK,
+ IPROC_ADC_INTR_MASK,
+ ((0x1 << channel) <<
+ IPROC_ADC_INTR));
+
+ regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val_check);
+ }
+
+ if (failed_cnt) {
+ dev_dbg(&indio_dev->dev,
+ "IntMask failed (%d times)", failed_cnt);
+ if (failed_cnt > IPROC_ADC_INTMASK_RETRY_ATTEMPTS) {
+ dev_err(&indio_dev->dev,
+ "IntMask set failed. Read will likely fail.");
+ read_len = -EIO;
+ goto adc_err;
+ };
+ }
+ regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val_check);
+
+ if (wait_for_completion_timeout(&adc_priv->completion,
+ IPROC_ADC_READ_TIMEOUT) > 0) {
+
+ /* Only the lower 16 bits are relevant */
+ *p_adc_data = adc_priv->chan_val & 0xFFFF;
+ read_len = sizeof(*p_adc_data);
+
+ } else {
+ /*
+ * We never got the interrupt, something went wrong.
+ * Perhaps the interrupt may still be coming, we do not want
+ * that now. Lets disable the ADC interrupt, and clear the
+ * status to put it back in to normal state.
+ */
+ read_len = -ETIMEDOUT;
+ goto adc_err;
+ }
+ mutex_unlock(&adc_priv->mutex);
+
+ return read_len;
+
+adc_err:
+ regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_MASK,
+ IPROC_ADC_INTR_MASK,
+ ((0x0 << channel) << IPROC_ADC_INTR));
+
+ regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_STATUS,
+ IPROC_ADC_INTR_MASK,
+ ((0x0 << channel) << IPROC_ADC_INTR));
+
+ dev_err(&indio_dev->dev, "Timed out waiting for ADC data!\n");
+ iproc_adc_reg_dump(indio_dev);
+ mutex_unlock(&adc_priv->mutex);
+
+ return read_len;
+}
+
+static int iproc_adc_enable(struct iio_dev *indio_dev)
+{
+ u32 val;
+ u32 channel_id;
+ struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
+ int ret;
+
+ /* Set i_amux = 3b'000, select channel 0 */
+ ret = regmap_update_bits(adc_priv->regmap, IPROC_ANALOG_CONTROL,
+ IPROC_ADC_CHANNEL_SEL_MASK, 0);
+ if (ret) {
+ dev_err(&indio_dev->dev,
+ "failed to write IPROC_ANALOG_CONTROL %d\n", ret);
+ return ret;
+ }
+ adc_priv->chan_val = -1;
+
+ /*
+ * PWR up LDO, ADC, and Band Gap (0 to enable)
+ * Also enable ADC controller (set high)
+ */
+ ret = regmap_read(adc_priv->regmap, IPROC_REGCTL2, &val);
+ if (ret) {
+ dev_err(&indio_dev->dev,
+ "failed to read IPROC_REGCTL2 %d\n", ret);
+ return ret;
+ }
+
+ val &= ~(IPROC_ADC_PWR_LDO | IPROC_ADC_PWR_ADC | IPROC_ADC_PWR_BG);
+
+ ret = regmap_write(adc_priv->regmap, IPROC_REGCTL2, val);
+ if (ret) {
+ dev_err(&indio_dev->dev,
+ "failed to write IPROC_REGCTL2 %d\n", ret);
+ return ret;
+ }
+
+ ret = regmap_read(adc_priv->regmap, IPROC_REGCTL2, &val);
+ if (ret) {
+ dev_err(&indio_dev->dev,
+ "failed to read IPROC_REGCTL2 %d\n", ret);
+ return ret;
+ }
+
+ val |= IPROC_ADC_CONTROLLER_EN;
+ ret = regmap_write(adc_priv->regmap, IPROC_REGCTL2, val);
+ if (ret) {
+ dev_err(&indio_dev->dev,
+ "failed to write IPROC_REGCTL2 %d\n", ret);
+ return ret;
+ }
+
+ for (channel_id = 0; channel_id < indio_dev->num_channels;
+ channel_id++) {
+ ret = regmap_write(adc_priv->regmap,
+ IPROC_ADC_CHANNEL_INTERRUPT_MASK +
+ IPROC_ADC_CHANNEL_OFFSET * channel_id, 0);
+ if (ret) {
+ dev_err(&indio_dev->dev,
+ "failed to write ADC_CHANNEL_INTERRUPT_MASK %d\n",
+ ret);
+ return ret;
+ }
+
+ ret = regmap_write(adc_priv->regmap,
+ IPROC_ADC_CHANNEL_INTERRUPT_STATUS +
+ IPROC_ADC_CHANNEL_OFFSET * channel_id, 0);
+ if (ret) {
+ dev_err(&indio_dev->dev,
+ "failed to write ADC_CHANNEL_INTERRUPT_STATUS %d\n",
+ ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static void iproc_adc_disable(struct iio_dev *indio_dev)
+{
+ u32 val;
+ int ret;
+ struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
+
+ ret = regmap_read(adc_priv->regmap, IPROC_REGCTL2, &val);
+ if (ret) {
+ dev_err(&indio_dev->dev,
+ "failed to read IPROC_REGCTL2 %d\n", ret);
+ return;
+ }
+
+ val &= ~IPROC_ADC_CONTROLLER_EN;
+ ret = regmap_write(adc_priv->regmap, IPROC_REGCTL2, val);
+ if (ret) {
+ dev_err(&indio_dev->dev,
+ "failed to write IPROC_REGCTL2 %d\n", ret);
+ return;
+ }
+}
+
+static int iproc_adc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long mask)
+{
+ u16 adc_data;
+ int err;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ err = iproc_adc_do_read(indio_dev, chan->channel, &adc_data);
+ if (err < 0)
+ return err;
+ *val = adc_data;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_VOLTAGE:
+ *val = 1800;
+ *val2 = 10;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ default:
+ return -EINVAL;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info iproc_adc_iio_info = {
+ .read_raw = &iproc_adc_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+#define IPROC_ADC_CHANNEL(_index, _id) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = _index, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .datasheet_name = _id, \
+}
+
+static const struct iio_chan_spec iproc_adc_iio_channels[] = {
+ IPROC_ADC_CHANNEL(0, "adc0"),
+ IPROC_ADC_CHANNEL(1, "adc1"),
+ IPROC_ADC_CHANNEL(2, "adc2"),
+ IPROC_ADC_CHANNEL(3, "adc3"),
+ IPROC_ADC_CHANNEL(4, "adc4"),
+ IPROC_ADC_CHANNEL(5, "adc5"),
+ IPROC_ADC_CHANNEL(6, "adc6"),
+ IPROC_ADC_CHANNEL(7, "adc7"),
+};
+
+static int iproc_adc_probe(struct platform_device *pdev)
+{
+ struct iproc_adc_priv *adc_priv;
+ struct iio_dev *indio_dev = NULL;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev,
+ sizeof(*adc_priv));
+ if (!indio_dev) {
+ dev_err(&pdev->dev, "failed to allocate iio device\n");
+ return -ENOMEM;
+ }
+
+ adc_priv = iio_priv(indio_dev);
+ platform_set_drvdata(pdev, indio_dev);
+
+ mutex_init(&adc_priv->mutex);
+
+ init_completion(&adc_priv->completion);
+
+ adc_priv->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
+ "adc-syscon");
+ if (IS_ERR(adc_priv->regmap)) {
+ dev_err(&pdev->dev, "failed to get handle for tsc syscon\n");
+ ret = PTR_ERR(adc_priv->regmap);
+ return ret;
+ }
+
+ adc_priv->adc_clk = devm_clk_get(&pdev->dev, "tsc_clk");
+ if (IS_ERR(adc_priv->adc_clk)) {
+ dev_err(&pdev->dev,
+ "failed getting clock tsc_clk\n");
+ ret = PTR_ERR(adc_priv->adc_clk);
+ return ret;
+ }
+
+ adc_priv->irqno = platform_get_irq(pdev, 0);
+ if (adc_priv->irqno <= 0) {
+ dev_err(&pdev->dev, "platform_get_irq failed\n");
+ ret = -ENODEV;
+ return ret;
+ }
+
+ ret = regmap_update_bits(adc_priv->regmap, IPROC_REGCTL2,
+ IPROC_ADC_AUXIN_SCAN_ENA, 0);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to write IPROC_REGCTL2 %d\n", ret);
+ return ret;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, adc_priv->irqno,
+ iproc_adc_interrupt_thread,
+ iproc_adc_interrupt_handler,
+ IRQF_SHARED, "iproc-adc", indio_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "request_irq error %d\n", ret);
+ return ret;
+ }
+
+ ret = clk_prepare_enable(adc_priv->adc_clk);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "clk_prepare_enable failed %d\n", ret);
+ return ret;
+ }
+
+ ret = iproc_adc_enable(indio_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to enable adc %d\n", ret);
+ goto err_adc_enable;
+ }
+
+ indio_dev->name = dev_name(&pdev->dev);
+ indio_dev->dev.parent = &pdev->dev;
+ indio_dev->dev.of_node = pdev->dev.of_node;
+ indio_dev->info = &iproc_adc_iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = iproc_adc_iio_channels;
+ indio_dev->num_channels = ARRAY_SIZE(iproc_adc_iio_channels);
+
+ ret = iio_device_register(indio_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "iio_device_register failed:err %d\n", ret);
+ goto err_clk;
+ }
+
+ return 0;
+
+err_clk:
+ iproc_adc_disable(indio_dev);
+err_adc_enable:
+ clk_disable_unprepare(adc_priv->adc_clk);
+
+ return ret;
+}
+
+static int iproc_adc_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ iproc_adc_disable(indio_dev);
+ clk_disable_unprepare(adc_priv->adc_clk);
+
+ return 0;
+}
+
+static const struct of_device_id iproc_adc_of_match[] = {
+ {.compatible = "brcm,iproc-static-adc", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, iproc_adc_of_match);
+
+static struct platform_driver iproc_adc_driver = {
+ .probe = iproc_adc_probe,
+ .remove = iproc_adc_remove,
+ .driver = {
+ .name = "iproc-static-adc",
+ .of_match_table = of_match_ptr(iproc_adc_of_match),
+ },
+};
+
+
+module_platform_driver(iproc_adc_driver);
+
+MODULE_DESCRIPTION("IPROC ADC driver");
+MODULE_AUTHOR("Broadcom");
+MODULE_LICENSE("GPL v2");
--
1.9.1