iio: frequency: New driver for AD9523 SPI Low Jitter Clock Generator

Changes since V1:

Apply Jonathan's review feedback:
Revise device status attribute names, and split documentation into two sections.
Add additional comments, and fix indention issues.
Remove pointless zero initializations.
Revise return value handling.
Simplify some code sections.
Split store_eeprom and sync handling into separate functions.
Use strtobool where applicable.
Document platform data structures using kernel-doc style.

Use dev_to_iio_dev
write_raw IIO_CHAN_INFO_FREQUENCY: Reject values <= 0
Make patch target drivers/iio

Changes since V2:

Use for_each_clear_bit() and __set_bit() where applicable.
Add descriptive comment.
Avoid temporary for struct regulator.
spi_device_id name use ad9523-1, ad9523 will be added later.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

7 files changed, 1319 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-frequency-ad9523 b/Documentation/ABI/testing/sysfs-bus-iio-frequency-ad9523
new file mode 100644
index 000000000000..2ce9c3f68eee
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-frequency-ad9523
@@ -0,0 +1,37 @@
+What:		/sys/bus/iio/devices/iio:deviceX/pll2_feedback_clk_present
+What:		/sys/bus/iio/devices/iio:deviceX/pll2_reference_clk_present
+What:		/sys/bus/iio/devices/iio:deviceX/pll1_reference_clk_a_present
+What:		/sys/bus/iio/devices/iio:deviceX/pll1_reference_clk_b_present
+What:		/sys/bus/iio/devices/iio:deviceX/pll1_reference_clk_test_present
+What:		/sys/bus/iio/devices/iio:deviceX/vcxo_clk_present
+KernelVersion:	3.4.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Reading returns either '1' or '0'.
+		'1' means that the clock in question is present.
+		'0' means that the clock is missing.
+
+What:		/sys/bus/iio/devices/iio:deviceX/pllY_locked
+KernelVersion:	3.4.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Reading returns either '1' or '0'. '1' means that the
+		pllY is locked.
+
+What:		/sys/bus/iio/devices/iio:deviceX/store_eeprom
+KernelVersion:	3.4.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Writing '1' stores the current device configuration into
+		on-chip EEPROM. After power-up or chip reset the device will
+		automatically load the saved configuration.
+
+What:		/sys/bus/iio/devices/iio:deviceX/sync_dividers
+KernelVersion:	3.4.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Writing '1' triggers the clock distribution synchronization
+		functionality. All dividers are reset and the channels start
+		with their predefined phase offsets (out_altvoltageY_phase).
+		Writing this file has the effect as driving the external
+		/SYNC pin low.
diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
index cacc74d70241..64c88e5cda4d 100644
--- a/drivers/iio/Kconfig
+++ b/drivers/iio/Kconfig
@@ -51,5 +51,6 @@ config IIO_CONSUMERS_PER_TRIGGER
 source "drivers/iio/adc/Kconfig"
 source "drivers/iio/amplifiers/Kconfig"
 source "drivers/iio/light/Kconfig"
+source "drivers/iio/frequency/Kconfig"
 
 endif # IIO
diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
index 060b674d278c..bd801c0bbc2f 100644
--- a/drivers/iio/Makefile
+++ b/drivers/iio/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o
 obj-y += adc/
 obj-y += amplifiers/
 obj-y += light/
+obj-y += frequency/
diff --git a/drivers/iio/frequency/Kconfig b/drivers/iio/frequency/Kconfig
new file mode 100644
index 000000000000..0458c92464a3
--- /dev/null
+++ b/drivers/iio/frequency/Kconfig
@@ -0,0 +1,23 @@
+#
+# Frequency
+#	Direct Digital Synthesis drivers (DDS)
+#	Clock Distribution device drivers
+#	Phase-Locked Loop (PLL) frequency synthesizers
+#
+
+menu "Frequency Synthesizers DDS/PLL"
+
+menu "Clock Generator/Distribution"
+
+config AD9523
+	tristate "Analog Devices AD9523 Low Jitter Clock Generator"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices AD9523 Low Jitter
+	  Clock Generator. The driver provides direct access via sysfs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad9523.
+
+endmenu
+endmenu
diff --git a/drivers/iio/frequency/Makefile b/drivers/iio/frequency/Makefile
new file mode 100644
index 000000000000..1b5b22417da1
--- /dev/null
+++ b/drivers/iio/frequency/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile iio/frequency
+#
+
+obj-$(CONFIG_AD9523) += ad9523.o
diff --git a/drivers/iio/frequency/ad9523.c b/drivers/iio/frequency/ad9523.c
new file mode 100644
index 000000000000..7272924484c1
--- /dev/null
+++ b/drivers/iio/frequency/ad9523.c
@@ -0,0 +1,1057 @@
+/*
+ * AD9523 SPI Low Jitter Clock Generator
+ *
+ * Copyright 2012 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+#include <linux/regulator/consumer.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/frequency/ad9523.h>
+
+#define AD9523_READ	(1 << 15)
+#define AD9523_WRITE	(0 << 15)
+#define AD9523_CNT(x)	(((x) - 1) << 13)
+#define AD9523_ADDR(x)	((x) & 0xFFF)
+
+#define AD9523_R1B	(1 << 16)
+#define AD9523_R2B	(2 << 16)
+#define AD9523_R3B	(3 << 16)
+#define AD9523_TRANSF_LEN(x)			((x) >> 16)
+
+#define AD9523_SERIAL_PORT_CONFIG		(AD9523_R1B | 0x0)
+#define AD9523_VERSION_REGISTER			(AD9523_R1B | 0x2)
+#define AD9523_PART_REGISTER			(AD9523_R1B | 0x3)
+#define AD9523_READBACK_CTRL			(AD9523_R1B | 0x4)
+
+#define AD9523_EEPROM_CUSTOMER_VERSION_ID	(AD9523_R2B | 0x6)
+
+#define AD9523_PLL1_REF_A_DIVIDER		(AD9523_R2B | 0x11)
+#define AD9523_PLL1_REF_B_DIVIDER		(AD9523_R2B | 0x13)
+#define AD9523_PLL1_REF_TEST_DIVIDER		(AD9523_R1B | 0x14)
+#define AD9523_PLL1_FEEDBACK_DIVIDER		(AD9523_R2B | 0x17)
+#define AD9523_PLL1_CHARGE_PUMP_CTRL		(AD9523_R2B | 0x19)
+#define AD9523_PLL1_INPUT_RECEIVERS_CTRL	(AD9523_R1B | 0x1A)
+#define AD9523_PLL1_REF_CTRL			(AD9523_R1B | 0x1B)
+#define AD9523_PLL1_MISC_CTRL			(AD9523_R1B | 0x1C)
+#define AD9523_PLL1_LOOP_FILTER_CTRL		(AD9523_R1B | 0x1D)
+
+#define AD9523_PLL2_CHARGE_PUMP			(AD9523_R1B | 0xF0)
+#define AD9523_PLL2_FEEDBACK_DIVIDER_AB		(AD9523_R1B | 0xF1)
+#define AD9523_PLL2_CTRL			(AD9523_R1B | 0xF2)
+#define AD9523_PLL2_VCO_CTRL			(AD9523_R1B | 0xF3)
+#define AD9523_PLL2_VCO_DIVIDER			(AD9523_R1B | 0xF4)
+#define AD9523_PLL2_LOOP_FILTER_CTRL		(AD9523_R2B | 0xF6)
+#define AD9523_PLL2_R2_DIVIDER			(AD9523_R1B | 0xF7)
+
+#define AD9523_CHANNEL_CLOCK_DIST(ch)		(AD9523_R3B | (0x192 + 3 * ch))
+
+#define AD9523_PLL1_OUTPUT_CTRL			(AD9523_R1B | 0x1BA)
+#define AD9523_PLL1_OUTPUT_CHANNEL_CTRL		(AD9523_R1B | 0x1BB)
+
+#define AD9523_READBACK_0			(AD9523_R1B | 0x22C)
+#define AD9523_READBACK_1			(AD9523_R1B | 0x22D)
+
+#define AD9523_STATUS_SIGNALS			(AD9523_R3B | 0x232)
+#define AD9523_POWER_DOWN_CTRL			(AD9523_R1B | 0x233)
+#define AD9523_IO_UPDATE			(AD9523_R1B | 0x234)
+
+#define AD9523_EEPROM_DATA_XFER_STATUS		(AD9523_R1B | 0xB00)
+#define AD9523_EEPROM_ERROR_READBACK		(AD9523_R1B | 0xB01)
+#define AD9523_EEPROM_CTRL1			(AD9523_R1B | 0xB02)
+#define AD9523_EEPROM_CTRL2			(AD9523_R1B | 0xB03)
+
+/* AD9523_SERIAL_PORT_CONFIG */
+
+#define AD9523_SER_CONF_SDO_ACTIVE		(1 << 7)
+#define AD9523_SER_CONF_SOFT_RESET		(1 << 5)
+
+/* AD9523_READBACK_CTRL */
+#define AD9523_READBACK_CTRL_READ_BUFFERED	(1 << 0)
+
+/* AD9523_PLL1_CHARGE_PUMP_CTRL */
+#define AD9523_PLL1_CHARGE_PUMP_CURRENT_nA(x)	(((x) / 500) & 0x7F)
+#define AD9523_PLL1_CHARGE_PUMP_TRISTATE	(1 << 7)
+#define AD9523_PLL1_CHARGE_PUMP_MODE_NORMAL	(3 << 8)
+#define AD9523_PLL1_CHARGE_PUMP_MODE_PUMP_DOWN	(2 << 8)
+#define AD9523_PLL1_CHARGE_PUMP_MODE_PUMP_UP	(1 << 8)
+#define AD9523_PLL1_CHARGE_PUMP_MODE_TRISTATE	(0 << 8)
+#define AD9523_PLL1_BACKLASH_PW_MIN		(0 << 10)
+#define AD9523_PLL1_BACKLASH_PW_LOW		(1 << 10)
+#define AD9523_PLL1_BACKLASH_PW_HIGH		(2 << 10)
+#define AD9523_PLL1_BACKLASH_PW_MAX		(3 << 10)
+
+/* AD9523_PLL1_INPUT_RECEIVERS_CTRL */
+#define AD9523_PLL1_REF_TEST_RCV_EN		(1 << 7)
+#define AD9523_PLL1_REFB_DIFF_RCV_EN		(1 << 6)
+#define AD9523_PLL1_REFA_DIFF_RCV_EN		(1 << 5)
+#define AD9523_PLL1_REFB_RCV_EN			(1 << 4)
+#define AD9523_PLL1_REFA_RCV_EN			(1 << 3)
+#define AD9523_PLL1_REFA_REFB_PWR_CTRL_EN	(1 << 2)
+#define AD9523_PLL1_OSC_IN_CMOS_NEG_INP_EN	(1 << 1)
+#define AD9523_PLL1_OSC_IN_DIFF_EN		(1 << 0)
+
+/* AD9523_PLL1_REF_CTRL */
+#define AD9523_PLL1_BYPASS_REF_TEST_DIV_EN	(1 << 7)
+#define AD9523_PLL1_BYPASS_FEEDBACK_DIV_EN	(1 << 6)
+#define AD9523_PLL1_ZERO_DELAY_MODE_INT		(1 << 5)
+#define AD9523_PLL1_ZERO_DELAY_MODE_EXT		(0 << 5)
+#define AD9523_PLL1_OSC_IN_PLL_FEEDBACK_EN	(1 << 4)
+#define AD9523_PLL1_ZD_IN_CMOS_NEG_INP_EN	(1 << 3)
+#define AD9523_PLL1_ZD_IN_DIFF_EN		(1 << 2)
+#define AD9523_PLL1_REFB_CMOS_NEG_INP_EN	(1 << 1)
+#define AD9523_PLL1_REFA_CMOS_NEG_INP_EN	(1 << 0)
+
+/* AD9523_PLL1_MISC_CTRL */
+#define AD9523_PLL1_REFB_INDEP_DIV_CTRL_EN	(1 << 7)
+#define AD9523_PLL1_OSC_CTRL_FAIL_VCC_BY2_EN	(1 << 6)
+#define AD9523_PLL1_REF_MODE(x)			((x) << 2)
+#define AD9523_PLL1_BYPASS_REFB_DIV		(1 << 1)
+#define AD9523_PLL1_BYPASS_REFA_DIV		(1 << 0)
+
+/* AD9523_PLL1_LOOP_FILTER_CTRL */
+#define AD9523_PLL1_LOOP_FILTER_RZERO(x)	((x) & 0xF)
+
+/* AD9523_PLL2_CHARGE_PUMP */
+#define AD9523_PLL2_CHARGE_PUMP_CURRENT_nA(x)	((x) / 3500)
+
+/* AD9523_PLL2_FEEDBACK_DIVIDER_AB */
+#define AD9523_PLL2_FB_NDIV_A_CNT(x)		(((x) & 0x3) << 6)
+#define AD9523_PLL2_FB_NDIV_B_CNT(x)		(((x) & 0x3F) << 0)
+#define AD9523_PLL2_FB_NDIV(a, b)		(4 * (b) + (a))
+
+/* AD9523_PLL2_CTRL */
+#define AD9523_PLL2_CHARGE_PUMP_MODE_NORMAL	(3 << 0)
+#define AD9523_PLL2_CHARGE_PUMP_MODE_PUMP_DOWN	(2 << 0)
+#define AD9523_PLL2_CHARGE_PUMP_MODE_PUMP_UP	(1 << 0)
+#define AD9523_PLL2_CHARGE_PUMP_MODE_TRISTATE	(0 << 0)
+#define AD9523_PLL2_BACKLASH_PW_MIN		(0 << 2)
+#define AD9523_PLL2_BACKLASH_PW_LOW		(1 << 2)
+#define AD9523_PLL2_BACKLASH_PW_HIGH		(2 << 2)
+#define AD9523_PLL2_BACKLASH_PW_MAX		(3 << 1)
+#define AD9523_PLL2_BACKLASH_CTRL_EN		(1 << 4)
+#define AD9523_PLL2_FREQ_DOUBLER_EN		(1 << 5)
+#define AD9523_PLL2_LOCK_DETECT_PWR_DOWN_EN	(1 << 7)
+
+/* AD9523_PLL2_VCO_CTRL */
+#define AD9523_PLL2_VCO_CALIBRATE		(1 << 1)
+#define AD9523_PLL2_FORCE_VCO_MIDSCALE		(1 << 2)
+#define AD9523_PLL2_FORCE_REFERENCE_VALID	(1 << 3)
+#define AD9523_PLL2_FORCE_RELEASE_SYNC		(1 << 4)
+
+/* AD9523_PLL2_VCO_DIVIDER */
+#define AD9523_PLL2_VCO_DIV_M1(x)		((((x) - 3) & 0x3) << 0)
+#define AD9523_PLL2_VCO_DIV_M2(x)		((((x) - 3) & 0x3) << 4)
+#define AD9523_PLL2_VCO_DIV_M1_PWR_DOWN_EN	(1 << 2)
+#define AD9523_PLL2_VCO_DIV_M2_PWR_DOWN_EN	(1 << 6)
+
+/* AD9523_PLL2_LOOP_FILTER_CTRL */
+#define AD9523_PLL2_LOOP_FILTER_CPOLE1(x)	(((x) & 0x7) << 0)
+#define AD9523_PLL2_LOOP_FILTER_RZERO(x)	(((x) & 0x7) << 3)
+#define AD9523_PLL2_LOOP_FILTER_RPOLE2(x)	(((x) & 0x7) << 6)
+#define AD9523_PLL2_LOOP_FILTER_RZERO_BYPASS_EN	(1 << 8)
+
+/* AD9523_PLL2_R2_DIVIDER */
+#define AD9523_PLL2_R2_DIVIDER_VAL(x)		(((x) & 0x1F) << 0)
+
+/* AD9523_CHANNEL_CLOCK_DIST */
+#define AD9523_CLK_DIST_DIV_PHASE(x)		(((x) & 0x3F) << 18)
+#define AD9523_CLK_DIST_DIV_PHASE_REV(x)	((ret >> 18) & 0x3F)
+#define AD9523_CLK_DIST_DIV(x)			((((x) - 1) & 0x3FF) << 8)
+#define AD9523_CLK_DIST_DIV_REV(x)		(((ret >> 8) & 0x3FF) + 1)
+#define AD9523_CLK_DIST_INV_DIV_OUTPUT_EN	(1 << 7)
+#define AD9523_CLK_DIST_IGNORE_SYNC_EN		(1 << 6)
+#define AD9523_CLK_DIST_PWR_DOWN_EN		(1 << 5)
+#define AD9523_CLK_DIST_LOW_PWR_MODE_EN		(1 << 4)
+#define AD9523_CLK_DIST_DRIVER_MODE(x)		(((x) & 0xF) << 0)
+
+/* AD9523_PLL1_OUTPUT_CTRL */
+#define AD9523_PLL1_OUTP_CTRL_VCO_DIV_SEL_CH6_M2	(1 << 7)
+#define AD9523_PLL1_OUTP_CTRL_VCO_DIV_SEL_CH5_M2	(1 << 6)
+#define AD9523_PLL1_OUTP_CTRL_VCO_DIV_SEL_CH4_M2	(1 << 5)
+#define AD9523_PLL1_OUTP_CTRL_CMOS_DRV_WEAK		(1 << 4)
+#define AD9523_PLL1_OUTP_CTRL_OUTPUT_DIV_1		(0 << 0)
+#define AD9523_PLL1_OUTP_CTRL_OUTPUT_DIV_2		(1 << 0)
+#define AD9523_PLL1_OUTP_CTRL_OUTPUT_DIV_4		(2 << 0)
+#define AD9523_PLL1_OUTP_CTRL_OUTPUT_DIV_8		(4 << 0)
+#define AD9523_PLL1_OUTP_CTRL_OUTPUT_DIV_16		(8 << 0)
+
+/* AD9523_PLL1_OUTPUT_CHANNEL_CTRL */
+#define AD9523_PLL1_OUTP_CH_CTRL_OUTPUT_PWR_DOWN_EN	(1 << 7)
+#define AD9523_PLL1_OUTP_CH_CTRL_VCO_DIV_SEL_CH9_M2	(1 << 6)
+#define AD9523_PLL1_OUTP_CH_CTRL_VCO_DIV_SEL_CH8_M2	(1 << 5)
+#define AD9523_PLL1_OUTP_CH_CTRL_VCO_DIV_SEL_CH7_M2	(1 << 4)
+#define AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH3	(1 << 3)
+#define AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH2	(1 << 2)
+#define AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH1	(1 << 1)
+#define AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH0	(1 << 0)
+
+/* AD9523_READBACK_0 */
+#define AD9523_READBACK_0_STAT_PLL2_REF_CLK		(1 << 7)
+#define AD9523_READBACK_0_STAT_PLL2_FB_CLK		(1 << 6)
+#define AD9523_READBACK_0_STAT_VCXO			(1 << 5)
+#define AD9523_READBACK_0_STAT_REF_TEST			(1 << 4)
+#define AD9523_READBACK_0_STAT_REFB			(1 << 3)
+#define AD9523_READBACK_0_STAT_REFA			(1 << 2)
+#define AD9523_READBACK_0_STAT_PLL2_LD			(1 << 1)
+#define AD9523_READBACK_0_STAT_PLL1_LD			(1 << 0)
+
+/* AD9523_READBACK_1 */
+#define AD9523_READBACK_1_HOLDOVER_ACTIVE		(1 << 3)
+#define AD9523_READBACK_1_AUTOMODE_SEL_REFB		(1 << 2)
+#define AD9523_READBACK_1_VCO_CALIB_IN_PROGRESS		(1 << 0)
+
+/* AD9523_STATUS_SIGNALS */
+#define AD9523_STATUS_SIGNALS_SYNC_MAN_CTRL		(1 << 16)
+#define AD9523_STATUS_MONITOR_01_PLL12_LOCKED		(0x302)
+/* AD9523_POWER_DOWN_CTRL */
+#define AD9523_POWER_DOWN_CTRL_PLL1_PWR_DOWN		(1 << 2)
+#define AD9523_POWER_DOWN_CTRL_PLL2_PWR_DOWN		(1 << 1)
+#define AD9523_POWER_DOWN_CTRL_DIST_PWR_DOWN		(1 << 0)
+
+/* AD9523_IO_UPDATE */
+#define AD9523_IO_UPDATE_EN				(1 << 0)
+
+/* AD9523_EEPROM_DATA_XFER_STATUS */
+#define AD9523_EEPROM_DATA_XFER_IN_PROGRESS		(1 << 0)
+
+/* AD9523_EEPROM_ERROR_READBACK */
+#define AD9523_EEPROM_ERROR_READBACK_FAIL		(1 << 0)
+
+/* AD9523_EEPROM_CTRL1 */
+#define AD9523_EEPROM_CTRL1_SOFT_EEPROM			(1 << 1)
+#define AD9523_EEPROM_CTRL1_EEPROM_WRITE_PROT_DIS	(1 << 0)
+
+/* AD9523_EEPROM_CTRL2 */
+#define AD9523_EEPROM_CTRL2_REG2EEPROM			(1 << 0)
+
+#define AD9523_NUM_CHAN					14
+#define AD9523_NUM_CHAN_ALT_CLK_SRC			10
+
+/* Helpers to avoid excess line breaks */
+#define AD_IFE(_pde, _a, _b) ((pdata->_pde) ? _a : _b)
+#define AD_IF(_pde, _a) AD_IFE(_pde, _a, 0)
+
+enum {
+	AD9523_STAT_PLL1_LD,
+	AD9523_STAT_PLL2_LD,
+	AD9523_STAT_REFA,
+	AD9523_STAT_REFB,
+	AD9523_STAT_REF_TEST,
+	AD9523_STAT_VCXO,
+	AD9523_STAT_PLL2_FB_CLK,
+	AD9523_STAT_PLL2_REF_CLK,
+	AD9523_SYNC,
+	AD9523_EEPROM,
+};
+
+enum {
+	AD9523_VCO1,
+	AD9523_VCO2,
+	AD9523_VCXO,
+	AD9523_NUM_CLK_SRC,
+};
+
+struct ad9523_state {
+	struct spi_device		*spi;
+	struct regulator		*reg;
+	struct ad9523_platform_data	*pdata;
+	struct iio_chan_spec		ad9523_channels[AD9523_NUM_CHAN];
+
+	unsigned long		vcxo_freq;
+	unsigned long		vco_freq;
+	unsigned long		vco_out_freq[AD9523_NUM_CLK_SRC];
+	unsigned char		vco_out_map[AD9523_NUM_CHAN_ALT_CLK_SRC];
+
+	/*
+	 * DMA (thus cache coherency maintenance) requires the
+	 * transfer buffers to live in their own cache lines.
+	 */
+	union {
+		__be32 d32;
+		u8 d8[4];
+	} data[2] ____cacheline_aligned;
+};
+
+static int ad9523_read(struct iio_dev *indio_dev, unsigned addr)
+{
+	struct ad9523_state *st = iio_priv(indio_dev);
+	struct spi_message m;
+	int ret;
+
+	/* We encode the register size 1..3 bytes into the register address.
+	 * On transfer we get the size from the register datum, and make sure
+	 * the result is properly aligned.
+	 */
+
+	struct spi_transfer t[] = {
+		{
+			.tx_buf = &st->data[0].d8[2],
+			.len = 2,
+		}, {
+			.rx_buf = &st->data[1].d8[4 - AD9523_TRANSF_LEN(addr)],
+			.len = AD9523_TRANSF_LEN(addr),
+		},
+	};
+
+	spi_message_init(&m);
+	spi_message_add_tail(&t[0], &m);
+	spi_message_add_tail(&t[1], &m);
+
+	st->data[0].d32 = cpu_to_be32(AD9523_READ |
+				      AD9523_CNT(AD9523_TRANSF_LEN(addr)) |
+				      AD9523_ADDR(addr));
+
+	ret = spi_sync(st->spi, &m);
+	if (ret < 0)
+		dev_err(&indio_dev->dev, "read failed (%d)", ret);
+	else
+		ret = be32_to_cpu(st->data[1].d32) & (0xFFFFFF >>
+				  (8 * (3 - AD9523_TRANSF_LEN(addr))));
+
+	return ret;
+};
+
+static int ad9523_write(struct iio_dev *indio_dev, unsigned addr, unsigned val)
+{
+	struct ad9523_state *st = iio_priv(indio_dev);
+	struct spi_message m;
+	int ret;
+	struct spi_transfer t[] = {
+		{
+			.tx_buf = &st->data[0].d8[2],
+			.len = 2,
+		}, {
+			.tx_buf = &st->data[1].d8[4 - AD9523_TRANSF_LEN(addr)],
+			.len = AD9523_TRANSF_LEN(addr),
+		},
+	};
+
+	spi_message_init(&m);
+	spi_message_add_tail(&t[0], &m);
+	spi_message_add_tail(&t[1], &m);
+
+	st->data[0].d32 = cpu_to_be32(AD9523_WRITE |
+				      AD9523_CNT(AD9523_TRANSF_LEN(addr)) |
+				      AD9523_ADDR(addr));
+	st->data[1].d32 = cpu_to_be32(val);
+
+	ret = spi_sync(st->spi, &m);
+
+	if (ret < 0)
+		dev_err(&indio_dev->dev, "write failed (%d)", ret);
+
+	return ret;
+}
+
+static int ad9523_io_update(struct iio_dev *indio_dev)
+{
+	return ad9523_write(indio_dev, AD9523_IO_UPDATE, AD9523_IO_UPDATE_EN);
+}
+
+static int ad9523_vco_out_map(struct iio_dev *indio_dev,
+			      unsigned ch, bool out)
+{
+	struct ad9523_state *st = iio_priv(indio_dev);
+	int ret;
+	unsigned mask;
+
+	switch (ch) {
+	case 0 ... 3:
+		ret = ad9523_read(indio_dev, AD9523_PLL1_OUTPUT_CHANNEL_CTRL);
+		if (ret < 0)
+			break;
+		mask = AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH0 << ch;
+		if (out) {
+			ret |= mask;
+			out = 2;
+		} else {
+			ret &= ~mask;
+		}
+		ret = ad9523_write(indio_dev,
+				   AD9523_PLL1_OUTPUT_CHANNEL_CTRL, ret);
+		break;
+	case 4 ... 6:
+		ret = ad9523_read(indio_dev, AD9523_PLL1_OUTPUT_CTRL);
+		if (ret < 0)
+			break;
+		mask = AD9523_PLL1_OUTP_CTRL_VCO_DIV_SEL_CH4_M2 << (ch - 4);
+		if (out)
+			ret |= mask;
+		else
+			ret &= ~mask;
+		ret = ad9523_write(indio_dev, AD9523_PLL1_OUTPUT_CTRL, ret);
+		break;
+	case 7 ... 9:
+		ret = ad9523_read(indio_dev, AD9523_PLL1_OUTPUT_CHANNEL_CTRL);
+		if (ret < 0)
+			break;
+		mask = AD9523_PLL1_OUTP_CH_CTRL_VCO_DIV_SEL_CH7_M2 << (ch - 7);
+		if (out)
+			ret |= mask;
+		else
+			ret &= ~mask;
+		ret = ad9523_write(indio_dev,
+				   AD9523_PLL1_OUTPUT_CHANNEL_CTRL, ret);
+		break;
+	default:
+		return 0;
+	}
+
+	st->vco_out_map[ch] = out;
+
+	return ret;
+}
+
+static int ad9523_set_clock_provider(struct iio_dev *indio_dev,
+			      unsigned ch, unsigned long freq)
+{
+	struct ad9523_state *st = iio_priv(indio_dev);
+	long tmp1, tmp2;
+	bool use_alt_clk_src;
+
+	switch (ch) {
+	case 0 ... 3:
+		use_alt_clk_src = (freq == st->vco_out_freq[AD9523_VCXO]);
+		break;
+	case 4 ... 9:
+		tmp1 = st->vco_out_freq[AD9523_VCO1] / freq;
+		tmp2 = st->vco_out_freq[AD9523_VCO2] / freq;
+		tmp1 *= freq;
+		tmp2 *= freq;
+		use_alt_clk_src = (abs(tmp1 - freq) > abs(tmp2 - freq));
+		break;
+	default:
+		/* Ch 10..14: No action required, return success */
+		return 0;
+	}
+
+	return ad9523_vco_out_map(indio_dev, ch, use_alt_clk_src);
+}
+
+static int ad9523_store_eeprom(struct iio_dev *indio_dev)
+{
+	int ret, tmp;
+
+	ret = ad9523_write(indio_dev, AD9523_EEPROM_CTRL1,
+			   AD9523_EEPROM_CTRL1_EEPROM_WRITE_PROT_DIS);
+	if (ret < 0)
+		return ret;
+	ret = ad9523_write(indio_dev, AD9523_EEPROM_CTRL2,
+			   AD9523_EEPROM_CTRL2_REG2EEPROM);
+	if (ret < 0)
+		return ret;
+
+	tmp = 4;
+	do {
+		msleep(16);
+		ret = ad9523_read(indio_dev,
+				  AD9523_EEPROM_DATA_XFER_STATUS);
+		if (ret < 0)
+			return ret;
+	} while ((ret & AD9523_EEPROM_DATA_XFER_IN_PROGRESS) && tmp--);
+
+	ret = ad9523_write(indio_dev, AD9523_EEPROM_CTRL1, 0);
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_read(indio_dev, AD9523_EEPROM_ERROR_READBACK);
+	if (ret < 0)
+		return ret;
+
+	if (ret & AD9523_EEPROM_ERROR_READBACK_FAIL) {
+		dev_err(&indio_dev->dev, "Verify EEPROM failed");
+		ret = -EIO;
+	}
+
+	return ret;
+}
+
+static int ad9523_sync(struct iio_dev *indio_dev)
+{
+	int ret, tmp;
+
+	ret = ad9523_read(indio_dev, AD9523_STATUS_SIGNALS);
+	if (ret < 0)
+		return ret;
+
+	tmp = ret;
+	tmp |= AD9523_STATUS_SIGNALS_SYNC_MAN_CTRL;
+
+	ret = ad9523_write(indio_dev, AD9523_STATUS_SIGNALS, tmp);
+	if (ret < 0)
+		return ret;
+
+	ad9523_io_update(indio_dev);
+	tmp &= ~AD9523_STATUS_SIGNALS_SYNC_MAN_CTRL;
+
+	ret = ad9523_write(indio_dev, AD9523_STATUS_SIGNALS, tmp);
+	if (ret < 0)
+		return ret;
+
+	return ad9523_io_update(indio_dev);
+}
+
+static ssize_t ad9523_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	bool state;
+	int ret;
+
+	ret = strtobool(buf, &state);
+	if (ret < 0)
+		return ret;
+
+	if (!state)
+		return 0;
+
+	mutex_lock(&indio_dev->mlock);
+	switch ((u32)this_attr->address) {
+	case AD9523_SYNC:
+		ret = ad9523_sync(indio_dev);
+		break;
+	case AD9523_EEPROM:
+		ret = ad9523_store_eeprom(indio_dev);
+		break;
+	default:
+		ret = -ENODEV;
+	}
+	mutex_unlock(&indio_dev->mlock);
+
+	return ret ? ret : len;
+}
+
+static ssize_t ad9523_show(struct device *dev,
+			struct device_attribute *attr,
+			char *buf)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	int ret;
+
+	mutex_lock(&indio_dev->mlock);
+	ret = ad9523_read(indio_dev, AD9523_READBACK_0);
+	if (ret >= 0) {
+		ret = sprintf(buf, "%d\n", !!(ret & (1 <<
+			(u32)this_attr->address)));
+	}
+	mutex_unlock(&indio_dev->mlock);
+
+	return ret;
+}
+
+static IIO_DEVICE_ATTR(pll1_locked, S_IRUGO,
+			ad9523_show,
+			NULL,
+			AD9523_STAT_PLL1_LD);
+
+static IIO_DEVICE_ATTR(pll2_locked, S_IRUGO,
+			ad9523_show,
+			NULL,
+			AD9523_STAT_PLL2_LD);
+
+static IIO_DEVICE_ATTR(pll1_reference_clk_a_present, S_IRUGO,
+			ad9523_show,
+			NULL,
+			AD9523_STAT_REFA);
+
+static IIO_DEVICE_ATTR(pll1_reference_clk_b_present, S_IRUGO,
+			ad9523_show,
+			NULL,
+			AD9523_STAT_REFB);
+
+static IIO_DEVICE_ATTR(pll1_reference_clk_test_present, S_IRUGO,
+			ad9523_show,
+			NULL,
+			AD9523_STAT_REF_TEST);
+
+static IIO_DEVICE_ATTR(vcxo_clk_present, S_IRUGO,
+			ad9523_show,
+			NULL,
+			AD9523_STAT_VCXO);
+
+static IIO_DEVICE_ATTR(pll2_feedback_clk_present, S_IRUGO,
+			ad9523_show,
+			NULL,
+			AD9523_STAT_PLL2_FB_CLK);
+
+static IIO_DEVICE_ATTR(pll2_reference_clk_present, S_IRUGO,
+			ad9523_show,
+			NULL,
+			AD9523_STAT_PLL2_REF_CLK);
+
+static IIO_DEVICE_ATTR(sync_dividers, S_IWUSR,
+			NULL,
+			ad9523_store,
+			AD9523_SYNC);
+
+static IIO_DEVICE_ATTR(store_eeprom, S_IWUSR,
+			NULL,
+			ad9523_store,
+			AD9523_EEPROM);
+
+static struct attribute *ad9523_attributes[] = {
+	&iio_dev_attr_sync_dividers.dev_attr.attr,
+	&iio_dev_attr_store_eeprom.dev_attr.attr,
+	&iio_dev_attr_pll2_feedback_clk_present.dev_attr.attr,
+	&iio_dev_attr_pll2_reference_clk_present.dev_attr.attr,
+	&iio_dev_attr_pll1_reference_clk_a_present.dev_attr.attr,
+	&iio_dev_attr_pll1_reference_clk_b_present.dev_attr.attr,
+	&iio_dev_attr_pll1_reference_clk_test_present.dev_attr.attr,
+	&iio_dev_attr_vcxo_clk_present.dev_attr.attr,
+	&iio_dev_attr_pll1_locked.dev_attr.attr,
+	&iio_dev_attr_pll2_locked.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ad9523_attribute_group = {
+	.attrs = ad9523_attributes,
+};
+
+static int ad9523_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	struct ad9523_state *st = iio_priv(indio_dev);
+	unsigned code;
+	int ret;
+
+	mutex_lock(&indio_dev->mlock);
+	ret = ad9523_read(indio_dev, AD9523_CHANNEL_CLOCK_DIST(chan->channel));
+	mutex_unlock(&indio_dev->mlock);
+
+	if (ret < 0)
+		return ret;
+
+	switch (m) {
+	case IIO_CHAN_INFO_RAW:
+		*val = !(ret & AD9523_CLK_DIST_PWR_DOWN_EN);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_FREQUENCY:
+		*val = st->vco_out_freq[st->vco_out_map[chan->channel]] /
+			AD9523_CLK_DIST_DIV_REV(ret);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_PHASE:
+		code = (AD9523_CLK_DIST_DIV_PHASE_REV(ret) * 3141592) /
+			AD9523_CLK_DIST_DIV_REV(ret);
+		*val = code / 1000000;
+		*val2 = (code % 1000000) * 10;
+		return IIO_VAL_INT_PLUS_MICRO;
+	default:
+		return -EINVAL;
+	}
+};
+
+static int ad9523_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val,
+			    int val2,
+			    long mask)
+{
+	struct ad9523_state *st = iio_priv(indio_dev);
+	unsigned reg;
+	int ret, tmp, code;
+
+	mutex_lock(&indio_dev->mlock);
+	ret = ad9523_read(indio_dev, AD9523_CHANNEL_CLOCK_DIST(chan->channel));
+	if (ret < 0)
+		goto out;
+
+	reg = ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (val)
+			reg &= ~AD9523_CLK_DIST_PWR_DOWN_EN;
+		else
+			reg |= AD9523_CLK_DIST_PWR_DOWN_EN;
+		break;
+	case IIO_CHAN_INFO_FREQUENCY:
+		if (val <= 0) {
+			ret = -EINVAL;
+			goto out;
+		}
+		ret = ad9523_set_clock_provider(indio_dev, chan->channel, val);
+		if (ret < 0)
+			goto out;
+		tmp = st->vco_out_freq[st->vco_out_map[chan->channel]] / val;
+		tmp = clamp(tmp, 1, 1024);
+		reg &= ~(0x3FF << 8);
+		reg |= AD9523_CLK_DIST_DIV(tmp);
+		break;
+	case IIO_CHAN_INFO_PHASE:
+		code = val * 1000000 + val2 % 1000000;
+		tmp = (code * AD9523_CLK_DIST_DIV_REV(ret)) / 3141592;
+		tmp = clamp(tmp, 0, 63);
+		reg &= ~AD9523_CLK_DIST_DIV_PHASE(~0);
+		reg |= AD9523_CLK_DIST_DIV_PHASE(tmp);
+		break;
+	default:
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = ad9523_write(indio_dev, AD9523_CHANNEL_CLOCK_DIST(chan->channel),
+			   reg);
+	if (ret < 0)
+		goto out;
+
+	ad9523_io_update(indio_dev);
+out:
+	mutex_unlock(&indio_dev->mlock);
+	return ret;
+}
+
+static int ad9523_reg_access(struct iio_dev *indio_dev,
+			      unsigned reg, unsigned writeval,
+			      unsigned *readval)
+{
+	int ret;
+
+	mutex_lock(&indio_dev->mlock);
+	if (readval == NULL) {
+		ret = ad9523_write(indio_dev, reg | AD9523_R1B, writeval);
+		ad9523_io_update(indio_dev);
+	} else {
+		ret = ad9523_read(indio_dev, reg | AD9523_R1B);
+		if (ret < 0)
+			return ret;
+		*readval = ret;
+		ret = 0;
+	}
+	mutex_unlock(&indio_dev->mlock);
+
+	return ret;
+}
+
+static const struct iio_info ad9523_info = {
+	.read_raw = &ad9523_read_raw,
+	.write_raw = &ad9523_write_raw,
+	.debugfs_reg_access = &ad9523_reg_access,
+	.attrs = &ad9523_attribute_group,
+	.driver_module = THIS_MODULE,
+};
+
+static int ad9523_setup(struct iio_dev *indio_dev)
+{
+	struct ad9523_state *st = iio_priv(indio_dev);
+	struct ad9523_platform_data *pdata = st->pdata;
+	struct ad9523_channel_spec *chan;
+	unsigned long active_mask = 0;
+	int ret, i;
+
+	ret = ad9523_write(indio_dev, AD9523_SERIAL_PORT_CONFIG,
+			   AD9523_SER_CONF_SOFT_RESET |
+			  (st->spi->mode & SPI_3WIRE ? 0 :
+			  AD9523_SER_CONF_SDO_ACTIVE));
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_READBACK_CTRL,
+			  AD9523_READBACK_CTRL_READ_BUFFERED);
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_io_update(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * PLL1 Setup
+	 */
+	ret = ad9523_write(indio_dev, AD9523_PLL1_REF_A_DIVIDER,
+		pdata->refa_r_div);
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL1_REF_B_DIVIDER,
+		pdata->refb_r_div);
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL1_FEEDBACK_DIVIDER,
+		pdata->pll1_feedback_div);
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL1_CHARGE_PUMP_CTRL,
+		AD9523_PLL1_CHARGE_PUMP_CURRENT_nA(pdata->
+			pll1_charge_pump_current_nA) |
+		AD9523_PLL1_CHARGE_PUMP_MODE_NORMAL |
+		AD9523_PLL1_BACKLASH_PW_MIN);
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL1_INPUT_RECEIVERS_CTRL,
+		AD_IF(refa_diff_rcv_en, AD9523_PLL1_REFA_RCV_EN) |
+		AD_IF(refb_diff_rcv_en, AD9523_PLL1_REFB_RCV_EN) |
+		AD_IF(osc_in_diff_en, AD9523_PLL1_OSC_IN_DIFF_EN) |
+		AD_IF(osc_in_cmos_neg_inp_en,
+		      AD9523_PLL1_OSC_IN_CMOS_NEG_INP_EN) |
+		AD_IF(refa_diff_rcv_en, AD9523_PLL1_REFA_DIFF_RCV_EN) |
+		AD_IF(refb_diff_rcv_en, AD9523_PLL1_REFB_DIFF_RCV_EN));
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL1_REF_CTRL,
+		AD_IF(zd_in_diff_en, AD9523_PLL1_ZD_IN_DIFF_EN) |
+		AD_IF(zd_in_cmos_neg_inp_en,
+		      AD9523_PLL1_ZD_IN_CMOS_NEG_INP_EN) |
+		AD_IF(zero_delay_mode_internal_en,
+		      AD9523_PLL1_ZERO_DELAY_MODE_INT) |
+		AD_IF(osc_in_feedback_en, AD9523_PLL1_OSC_IN_PLL_FEEDBACK_EN) |
+		AD_IF(refa_cmos_neg_inp_en, AD9523_PLL1_REFA_CMOS_NEG_INP_EN) |
+		AD_IF(refb_cmos_neg_inp_en, AD9523_PLL1_REFB_CMOS_NEG_INP_EN));
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL1_MISC_CTRL,
+		AD9523_PLL1_REFB_INDEP_DIV_CTRL_EN |
+		AD9523_PLL1_REF_MODE(pdata->ref_mode));
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL1_LOOP_FILTER_CTRL,
+		AD9523_PLL1_LOOP_FILTER_RZERO(pdata->pll1_loop_filter_rzero));
+	if (ret < 0)
+		return ret;
+	/*
+	 * PLL2 Setup
+	 */
+
+	ret = ad9523_write(indio_dev, AD9523_PLL2_CHARGE_PUMP,
+		AD9523_PLL2_CHARGE_PUMP_CURRENT_nA(pdata->
+			pll2_charge_pump_current_nA));
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL2_FEEDBACK_DIVIDER_AB,
+		AD9523_PLL2_FB_NDIV_A_CNT(pdata->pll2_ndiv_a_cnt) |
+		AD9523_PLL2_FB_NDIV_B_CNT(pdata->pll2_ndiv_b_cnt));
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL2_CTRL,
+		AD9523_PLL2_CHARGE_PUMP_MODE_NORMAL |
+		AD9523_PLL2_BACKLASH_CTRL_EN |
+		AD_IF(pll2_freq_doubler_en, AD9523_PLL2_FREQ_DOUBLER_EN));
+	if (ret < 0)
+		return ret;
+
+	st->vco_freq = (pdata->vcxo_freq * (pdata->pll2_freq_doubler_en ? 2 : 1)
+			/ pdata->pll2_r2_div) * AD9523_PLL2_FB_NDIV(pdata->
+			pll2_ndiv_a_cnt, pdata->pll2_ndiv_b_cnt);
+
+	ret = ad9523_write(indio_dev, AD9523_PLL2_VCO_CTRL,
+		AD9523_PLL2_VCO_CALIBRATE);
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL2_VCO_DIVIDER,
+		AD9523_PLL2_VCO_DIV_M1(pdata->pll2_vco_diff_m1) |
+		AD9523_PLL2_VCO_DIV_M2(pdata->pll2_vco_diff_m2) |
+		AD_IFE(pll2_vco_diff_m1, 0,
+		       AD9523_PLL2_VCO_DIV_M1_PWR_DOWN_EN) |
+		AD_IFE(pll2_vco_diff_m2, 0,
+		       AD9523_PLL2_VCO_DIV_M2_PWR_DOWN_EN));
+	if (ret < 0)
+		return ret;
+
+	if (pdata->pll2_vco_diff_m1)
+		st->vco_out_freq[AD9523_VCO1] =
+			st->vco_freq / pdata->pll2_vco_diff_m1;
+
+	if (pdata->pll2_vco_diff_m2)
+		st->vco_out_freq[AD9523_VCO2] =
+			st->vco_freq / pdata->pll2_vco_diff_m2;
+
+	st->vco_out_freq[AD9523_VCXO] = pdata->vcxo_freq;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL2_R2_DIVIDER,
+		AD9523_PLL2_R2_DIVIDER_VAL(pdata->pll2_r2_div));
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_PLL2_LOOP_FILTER_CTRL,
+		AD9523_PLL2_LOOP_FILTER_CPOLE1(pdata->cpole1) |
+		AD9523_PLL2_LOOP_FILTER_RZERO(pdata->rzero) |
+		AD9523_PLL2_LOOP_FILTER_RPOLE2(pdata->rpole2) |
+		AD_IF(rzero_bypass_en,
+		      AD9523_PLL2_LOOP_FILTER_RZERO_BYPASS_EN));
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < pdata->num_channels; i++) {
+		chan = &pdata->channels[i];
+		if (chan->channel_num < AD9523_NUM_CHAN) {
+			__set_bit(chan->channel_num, &active_mask);
+			ret = ad9523_write(indio_dev,
+				AD9523_CHANNEL_CLOCK_DIST(chan->channel_num),
+				AD9523_CLK_DIST_DRIVER_MODE(chan->driver_mode) |
+				AD9523_CLK_DIST_DIV(chan->channel_divider) |
+				AD9523_CLK_DIST_DIV_PHASE(chan->divider_phase) |
+				(chan->sync_ignore_en ?
+					AD9523_CLK_DIST_IGNORE_SYNC_EN : 0) |
+				(chan->divider_output_invert_en ?
+					AD9523_CLK_DIST_INV_DIV_OUTPUT_EN : 0) |
+				(chan->low_power_mode_en ?
+					AD9523_CLK_DIST_LOW_PWR_MODE_EN : 0) |
+				(chan->output_dis ?
+					AD9523_CLK_DIST_PWR_DOWN_EN : 0));
+			if (ret < 0)
+				return ret;
+
+			ret = ad9523_vco_out_map(indio_dev, chan->channel_num,
+					   chan->use_alt_clock_src);
+			if (ret < 0)
+				return ret;
+
+			st->ad9523_channels[i].type = IIO_ALTVOLTAGE;
+			st->ad9523_channels[i].output = 1;
+			st->ad9523_channels[i].indexed = 1;
+			st->ad9523_channels[i].channel = chan->channel_num;
+			st->ad9523_channels[i].extend_name =
+				chan->extended_name;
+			st->ad9523_channels[i].info_mask =
+				IIO_CHAN_INFO_RAW_SEPARATE_BIT |
+				IIO_CHAN_INFO_PHASE_SEPARATE_BIT |
+				IIO_CHAN_INFO_FREQUENCY_SEPARATE_BIT;
+		}
+	}
+
+	for_each_clear_bit(i, &active_mask, AD9523_NUM_CHAN)
+		ad9523_write(indio_dev,
+			     AD9523_CHANNEL_CLOCK_DIST(i),
+			     AD9523_CLK_DIST_DRIVER_MODE(TRISTATE) |
+			     AD9523_CLK_DIST_PWR_DOWN_EN);
+
+	ret = ad9523_write(indio_dev, AD9523_POWER_DOWN_CTRL, 0);
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_write(indio_dev, AD9523_STATUS_SIGNALS,
+			   AD9523_STATUS_MONITOR_01_PLL12_LOCKED);
+	if (ret < 0)
+		return ret;
+
+	ret = ad9523_io_update(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int __devinit ad9523_probe(struct spi_device *spi)
+{
+	struct ad9523_platform_data *pdata = spi->dev.platform_data;
+	struct iio_dev *indio_dev;
+	struct ad9523_state *st;
+	int ret;
+
+	if (!pdata) {
+		dev_err(&spi->dev, "no platform data?\n");
+		return -EINVAL;
+	}
+
+	indio_dev = iio_device_alloc(sizeof(*st));
+	if (indio_dev == NULL)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+
+	st->reg = regulator_get(&spi->dev, "vcc");
+	if (!IS_ERR(st->reg)) {
+		ret = regulator_enable(st->reg);
+		if (ret)
+			goto error_put_reg;
+	}
+
+	spi_set_drvdata(spi, indio_dev);
+	st->spi = spi;
+	st->pdata = pdata;
+
+	indio_dev->dev.parent = &spi->dev;
+	indio_dev->name = (pdata->name[0] != 0) ? pdata->name :
+			  spi_get_device_id(spi)->name;
+	indio_dev->info = &ad9523_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = st->ad9523_channels;
+	indio_dev->num_channels = pdata->num_channels;
+
+	ret = ad9523_setup(indio_dev);
+	if (ret < 0)
+		goto error_disable_reg;
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto error_disable_reg;
+
+	dev_info(&spi->dev, "probed %s\n", indio_dev->name);
+
+	return 0;
+
+error_disable_reg:
+	if (!IS_ERR(st->reg))
+		regulator_disable(st->reg);
+error_put_reg:
+	if (!IS_ERR(st->reg))
+		regulator_put(st->reg);
+
+	iio_device_free(indio_dev);
+
+	return ret;
+}
+
+static int __devexit ad9523_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct ad9523_state *st = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	if (!IS_ERR(st->reg)) {
+		regulator_disable(st->reg);
+		regulator_put(st->reg);
+	}
+
+	iio_device_free(indio_dev);
+
+	return 0;
+}
+
+static const struct spi_device_id ad9523_id[] = {
+	{"ad9523-1", 9523},
+	{}
+};
+MODULE_DEVICE_TABLE(spi, ad9523_id);
+
+static struct spi_driver ad9523_driver = {
+	.driver = {
+		.name	= "ad9523",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= ad9523_probe,
+	.remove		= __devexit_p(ad9523_remove),
+	.id_table	= ad9523_id,
+};
+module_spi_driver(ad9523_driver);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD9523 CLOCKDIST/PLL");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/iio/frequency/ad9523.h b/include/linux/iio/frequency/ad9523.h
new file mode 100644
index 000000000000..12ce3ee427fd
--- /dev/null
+++ b/include/linux/iio/frequency/ad9523.h
@@ -0,0 +1,195 @@
+/*
+ * AD9523 SPI Low Jitter Clock Generator
+ *
+ * Copyright 2012 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef IIO_FREQUENCY_AD9523_H_
+#define IIO_FREQUENCY_AD9523_H_
+
+enum outp_drv_mode {
+	TRISTATE,
+	LVPECL_8mA,
+	LVDS_4mA,
+	LVDS_7mA,
+	HSTL0_16mA,
+	HSTL1_8mA,
+	CMOS_CONF1,
+	CMOS_CONF2,
+	CMOS_CONF3,
+	CMOS_CONF4,
+	CMOS_CONF5,
+	CMOS_CONF6,
+	CMOS_CONF7,
+	CMOS_CONF8,
+	CMOS_CONF9
+};
+
+enum ref_sel_mode {
+	NONEREVERTIVE_STAY_ON_REFB,
+	REVERT_TO_REFA,
+	SELECT_REFA,
+	SELECT_REFB,
+	EXT_REF_SEL
+};
+
+/**
+ * struct ad9523_channel_spec - Output channel configuration
+ *
+ * @channel_num: Output channel number.
+ * @divider_output_invert_en: Invert the polarity of the output clock.
+ * @sync_ignore_en: Ignore chip-level SYNC signal.
+ * @low_power_mode_en: Reduce power used in the differential output modes.
+ * @use_alt_clock_src: Channel divider uses alternative clk source.
+ * @output_dis: Disables, powers down the entire channel.
+ * @driver_mode: Output driver mode (logic level family).
+ * @divider_phase: Divider initial phase after a SYNC. Range 0..63
+		   LSB = 1/2 of a period of the divider input clock.
+ * @channel_divider: 10-bit channel divider.
+ * @extended_name: Optional descriptive channel name.
+ */
+
+struct ad9523_channel_spec {
+	unsigned		channel_num;
+	bool			divider_output_invert_en;
+	bool			sync_ignore_en;
+	bool			low_power_mode_en;
+				 /* CH0..CH3 VCXO, CH4..CH9 VCO2 */
+	bool			use_alt_clock_src;
+	bool			output_dis;
+	enum outp_drv_mode	driver_mode;
+	unsigned char		divider_phase;
+	unsigned short		channel_divider;
+	char			extended_name[16];
+};
+
+enum pll1_rzero_resistor {
+	RZERO_883_OHM,
+	RZERO_677_OHM,
+	RZERO_341_OHM,
+	RZERO_135_OHM,
+	RZERO_10_OHM,
+	RZERO_USE_EXT_RES = 8,
+};
+
+enum rpole2_resistor {
+	RPOLE2_900_OHM,
+	RPOLE2_450_OHM,
+	RPOLE2_300_OHM,
+	RPOLE2_225_OHM,
+};
+
+enum rzero_resistor {
+	RZERO_3250_OHM,
+	RZERO_2750_OHM,
+	RZERO_2250_OHM,
+	RZERO_2100_OHM,
+	RZERO_3000_OHM,
+	RZERO_2500_OHM,
+	RZERO_2000_OHM,
+	RZERO_1850_OHM,
+};
+
+enum cpole1_capacitor {
+	CPOLE1_0_PF,
+	CPOLE1_8_PF,
+	CPOLE1_16_PF,
+	CPOLE1_24_PF,
+	_CPOLE1_24_PF, /* place holder */
+	CPOLE1_32_PF,
+	CPOLE1_40_PF,
+	CPOLE1_48_PF,
+};
+
+/**
+ * struct ad9523_platform_data - platform specific information
+ *
+ * @vcxo_freq: External VCXO frequency in Hz
+ * @refa_diff_rcv_en: REFA differential/single-ended input selection.
+ * @refb_diff_rcv_en: REFB differential/single-ended input selection.
+ * @zd_in_diff_en: Zero Delay differential/single-ended input selection.
+ * @osc_in_diff_en: OSC differential/ single-ended input selection.
+ * @refa_cmos_neg_inp_en: REFA single-ended neg./pos. input enable.
+ * @refb_cmos_neg_inp_en: REFB single-ended neg./pos. input enable.
+ * @zd_in_cmos_neg_inp_en: Zero Delay single-ended neg./pos. input enable.
+ * @osc_in_cmos_neg_inp_en: OSC single-ended neg./pos. input enable.
+ * @refa_r_div: PLL1 10-bit REFA R divider.
+ * @refb_r_div: PLL1 10-bit REFB R divider.
+ * @pll1_feedback_div: PLL1 10-bit Feedback N divider.
+ * @pll1_charge_pump_current_nA: Magnitude of PLL1 charge pump current (nA).
+ * @zero_delay_mode_internal_en: Internal, external Zero Delay mode selection.
+ * @osc_in_feedback_en: PLL1 feedback path, local feedback from
+ *			the OSC_IN receiver or zero delay mode
+ * @pll1_loop_filter_rzero: PLL1 Loop Filter Zero Resistor selection.
+ * @ref_mode: Reference selection mode.
+ * @pll2_charge_pump_current_nA: Magnitude of PLL2 charge pump current (nA).
+ * @pll2_ndiv_a_cnt: PLL2 Feedback N-divider, A Counter, range 0..4.
+ * @pll2_ndiv_b_cnt: PLL2 Feedback N-divider, B Counter, range 0..63.
+ * @pll2_freq_doubler_en: PLL2 frequency doubler enable.
+ * @pll2_r2_div: PLL2 R2 divider, range 0..31.
+ * @pll2_vco_diff_m1: VCO1 divider, range 3..5.
+ * @pll2_vco_diff_m2: VCO2 divider, range 3..5.
+ * @rpole2: PLL2 loop filter Rpole resistor value.
+ * @rzero: PLL2 loop filter Rzero resistor value.
+ * @cpole1: PLL2 loop filter Cpole capacitor value.
+ * @rzero_bypass_en: PLL2 loop filter Rzero bypass enable.
+ * @num_channels: Array size of struct ad9523_channel_spec.
+ * @channels: Pointer to channel array.
+ * @name: Optional alternative iio device name.
+ */
+
+struct ad9523_platform_data {
+	unsigned long vcxo_freq;
+
+	/* Differential/ Single-Ended Input Configuration */
+	bool				refa_diff_rcv_en;
+	bool				refb_diff_rcv_en;
+	bool				zd_in_diff_en;
+	bool				osc_in_diff_en;
+
+	/*
+	 * Valid if differential input disabled
+	 * if false defaults to pos input
+	 */
+	bool				refa_cmos_neg_inp_en;
+	bool				refb_cmos_neg_inp_en;
+	bool				zd_in_cmos_neg_inp_en;
+	bool				osc_in_cmos_neg_inp_en;
+
+	/* PLL1 Setting */
+	unsigned short			refa_r_div;
+	unsigned short			refb_r_div;
+	unsigned short			pll1_feedback_div;
+	unsigned short			pll1_charge_pump_current_nA;
+	bool				zero_delay_mode_internal_en;
+	bool				osc_in_feedback_en;
+	enum pll1_rzero_resistor	pll1_loop_filter_rzero;
+
+	/* Reference */
+	enum ref_sel_mode		ref_mode;
+
+	/* PLL2 Setting */
+	unsigned int			pll2_charge_pump_current_nA;
+	unsigned char			pll2_ndiv_a_cnt;
+	unsigned char			pll2_ndiv_b_cnt;
+	bool				pll2_freq_doubler_en;
+	unsigned char			pll2_r2_div;
+	unsigned char			pll2_vco_diff_m1; /* 3..5 */
+	unsigned char			pll2_vco_diff_m2; /* 3..5 */
+
+	/* Loop Filter PLL2 */
+	enum rpole2_resistor		rpole2;
+	enum rzero_resistor		rzero;
+	enum cpole1_capacitor		cpole1;
+	bool				rzero_bypass_en;
+
+	/* Output Channel Configuration */
+	int				num_channels;
+	struct ad9523_channel_spec	*channels;
+
+	char				name[SPI_NAME_SIZE];
+};
+
+#endif /* IIO_FREQUENCY_AD9523_H_ */