[media] media: i2c: max2175: Add MAX2175 support

This patch adds driver support for the MAX2175 chip. This is Maxim
Integrated's RF to Bits tuner front end chip designed for software-defined
radio solutions. This driver exposes the tuner as a sub-device instance
with standard and custom controls to configure the device.

Signed-off-by: Ramesh Shanmugasundaram <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

Documentation/media/v4l-drivers/index.rst

···
 	davinci-vpbe
 	fimc
 	ivtv
+	max2175
 	meye
 	omap3isp
 	omap4_camera

Documentation/media/v4l-drivers/max2175.rst

···
+Maxim Integrated MAX2175 RF to bits tuner driver
+================================================
+
+The MAX2175 driver implements the following driver-specific controls:
+
+``V4L2_CID_MAX2175_I2S_ENABLE``
+-------------------------------
+    Enable/Disable I2S output of the tuner. This is a private control
+    that can be accessed only using the subdev interface.
+    Refer to Documentation/media/kapi/v4l2-controls for more details.
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 4
+
+    * - ``(0)``
+      - I2S output is disabled.
+    * - ``(1)``
+      - I2S output is enabled.
+
+``V4L2_CID_MAX2175_HSLS``
+-------------------------
+    The high-side/low-side (HSLS) control of the tuner for a given band.
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 4
+
+    * - ``(0)``
+      - The LO frequency position is below the desired frequency.
+    * - ``(1)``
+      - The LO frequency position is above the desired frequency.
+
+``V4L2_CID_MAX2175_RX_MODE (menu)``
+-----------------------------------
+    The Rx mode controls a number of preset parameters of the tuner like
+    sample clock (sck), sampling rate etc. These multiple settings are
+    provided under one single label called Rx mode in the datasheet. The
+    list below shows the supported modes with a brief description.
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 4
+
+    * - ``"Europe modes"``
+    * - ``"FM 1.2" (0)``
+      - This configures FM band with a sample rate of 0.512 million
+        samples/sec with a 10.24 MHz sck.
+    * - ``"DAB 1.2" (1)``
+      - This configures VHF band with a sample rate of 2.048 million
+        samples/sec with a 32.768 MHz sck.
+
+    * - ``"North America modes"``
+    * - ``"FM 1.0" (0)``
+      - This configures FM band with a sample rate of 0.7441875 million
+        samples/sec with a 14.88375 MHz sck.
+    * - ``"DAB 1.2" (1)``
+      - This configures FM band with a sample rate of 0.372 million
+        samples/sec with a 7.441875 MHz sck.

drivers/media/i2c/Kconfig

···
 	  To compile this driver as a module, choose M here: the
 	  module will be called saa6752hs.
 
+comment "SDR tuner chips"
+
+config SDR_MAX2175
+	tristate "Maxim 2175 RF to Bits tuner"
+	depends on VIDEO_V4L2 && MEDIA_SDR_SUPPORT && I2C
+	---help---
+	  Support for Maxim 2175 tuner. It is an advanced analog/digital
+	  radio receiver with RF-to-Bits front-end designed for SDR solutions.
+
+	  To compile this driver as a module, choose M here; the
+	  module will be called max2175.
+
 comment "Miscellaneous helper chips"
 
 config VIDEO_THS7303

drivers/media/i2c/Makefile

···
 obj-$(CONFIG_VIDEO_ML86V7667)	+= ml86v7667.o
 obj-$(CONFIG_VIDEO_OV2659)	+= ov2659.o
 obj-$(CONFIG_VIDEO_TC358743)	+= tc358743.o
+
+obj-$(CONFIG_SDR_MAX2175) += max2175.o

drivers/media/i2c/max2175.c

···
+/*
+ * Maxim Integrated MAX2175 RF to Bits tuner driver
+ *
+ * This driver & most of the hard coded values are based on the reference
+ * application delivered by Maxim for this device.
+ *
+ * Copyright (C) 2016 Maxim Integrated Products
+ * Copyright (C) 2017 Renesas Electronics Corporation
+ *
+ * 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.
+ *
+ * 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/clk.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/math64.h>
+#include <linux/max2175.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+
+#include "max2175.h"
+
+#define DRIVER_NAME "max2175"
+
+#define mxm_dbg(ctx, fmt, arg...) dev_dbg(&ctx->client->dev, fmt, ## arg)
+#define mxm_err(ctx, fmt, arg...) dev_err(&ctx->client->dev, fmt, ## arg)
+
+/* Rx mode */
+struct max2175_rxmode {
+	enum max2175_band band;		/* Associated band */
+	u32 freq;			/* Default freq in Hz */
+	u8 i2s_word_size;		/* Bit value */
+};
+
+/* Register map to define preset values */
+struct max2175_reg_map {
+	u8 idx;				/* Register index */
+	u8 val;				/* Register value */
+};
+
+static const struct max2175_rxmode eu_rx_modes[] = {
+	/* EU modes */
+	[MAX2175_EU_FM_1_2] = { MAX2175_BAND_FM, 98256000, 1 },
+	[MAX2175_DAB_1_2]   = { MAX2175_BAND_VHF, 182640000, 0 },
+};
+
+static const struct max2175_rxmode na_rx_modes[] = {
+	/* NA modes */
+	[MAX2175_NA_FM_1_0] = { MAX2175_BAND_FM, 98255520, 1 },
+	[MAX2175_NA_FM_2_0] = { MAX2175_BAND_FM, 98255520, 6 },
+};
+
+/*
+ * Preset values:
+ * Based on Maxim MAX2175 Register Table revision: 130p10
+ */
+static const u8 full_fm_eu_1p0[] = {
+	0x15, 0x04, 0xb8, 0xe3, 0x35, 0x18, 0x7c, 0x00,
+	0x00, 0x7d, 0x40, 0x08, 0x70, 0x7a, 0x88, 0x91,
+	0x61, 0x61, 0x61, 0x61, 0x5a, 0x0f, 0x34, 0x1c,
+	0x14, 0x88, 0x33, 0x02, 0x00, 0x09, 0x00, 0x65,
+	0x9f, 0x2b, 0x80, 0x00, 0x95, 0x05, 0x2c, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x40,
+	0x4a, 0x08, 0xa8, 0x0e, 0x0e, 0x2f, 0x7e, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0xab, 0x5e, 0xa9,
+	0xae, 0xbb, 0x57, 0x18, 0x3b, 0x03, 0x3b, 0x64,
+	0x40, 0x60, 0x00, 0x2a, 0xbf, 0x3f, 0xff, 0x9f,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0a, 0x00,
+	0xff, 0xfc, 0xef, 0x1c, 0x40, 0x00, 0x00, 0x02,
+	0x00, 0x00, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0xac, 0x40, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x75, 0x00, 0x00,
+	0x00, 0x47, 0x00, 0x00, 0x11, 0x3f, 0x22, 0x00,
+	0xf1, 0x00, 0x41, 0x03, 0xb0, 0x00, 0x00, 0x00,
+	0x1b,
+};
+
+static const u8 full_fm_na_1p0[] = {
+	0x13, 0x08, 0x8d, 0xc0, 0x35, 0x18, 0x7d, 0x3f,
+	0x7d, 0x75, 0x40, 0x08, 0x70, 0x7a, 0x88, 0x91,
+	0x61, 0x61, 0x61, 0x61, 0x5c, 0x0f, 0x34, 0x1c,
+	0x14, 0x88, 0x33, 0x02, 0x00, 0x01, 0x00, 0x65,
+	0x9f, 0x2b, 0x80, 0x00, 0x95, 0x05, 0x2c, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x40,
+	0x4a, 0x08, 0xa8, 0x0e, 0x0e, 0xaf, 0x7e, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0xab, 0x5e, 0xa9,
+	0xae, 0xbb, 0x57, 0x18, 0x3b, 0x03, 0x3b, 0x64,
+	0x40, 0x60, 0x00, 0x2a, 0xbf, 0x3f, 0xff, 0x9f,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0a, 0x00,
+	0xff, 0xfc, 0xef, 0x1c, 0x40, 0x00, 0x00, 0x02,
+	0x00, 0x00, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0xa6, 0x40, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x75, 0x00, 0x00,
+	0x00, 0x35, 0x00, 0x00, 0x11, 0x3f, 0x22, 0x00,
+	0xf1, 0x00, 0x41, 0x03, 0xb0, 0x00, 0x00, 0x00,
+	0x1b,
+};
+
+/* DAB1.2 settings */
+static const struct max2175_reg_map dab12_map[] = {
+	{ 0x01, 0x13 }, { 0x02, 0x0d }, { 0x03, 0x15 }, { 0x04, 0x55 },
+	{ 0x05, 0x0a }, { 0x06, 0xa0 }, { 0x07, 0x40 }, { 0x08, 0x00 },
+	{ 0x09, 0x00 }, { 0x0a, 0x7d }, { 0x0b, 0x4a }, { 0x0c, 0x28 },
+	{ 0x0e, 0x43 }, { 0x0f, 0xb5 }, { 0x10, 0x31 }, { 0x11, 0x9e },
+	{ 0x12, 0x68 }, { 0x13, 0x9e }, { 0x14, 0x68 }, { 0x15, 0x58 },
+	{ 0x16, 0x2f }, { 0x17, 0x3f }, { 0x18, 0x40 }, { 0x1a, 0x88 },
+	{ 0x1b, 0xaa }, { 0x1c, 0x9a }, { 0x1d, 0x00 }, { 0x1e, 0x00 },
+	{ 0x23, 0x80 }, { 0x24, 0x00 }, { 0x25, 0x00 }, { 0x26, 0x00 },
+	{ 0x27, 0x00 }, { 0x32, 0x08 }, { 0x33, 0xf8 }, { 0x36, 0x2d },
+	{ 0x37, 0x7e }, { 0x55, 0xaf }, { 0x56, 0x3f }, { 0x57, 0xf8 },
+	{ 0x58, 0x99 }, { 0x76, 0x00 }, { 0x77, 0x00 }, { 0x78, 0x02 },
+	{ 0x79, 0x40 }, { 0x82, 0x00 }, { 0x83, 0x00 }, { 0x85, 0x00 },
+	{ 0x86, 0x20 },
+};
+
+/* EU FM 1.2 settings */
+static const struct max2175_reg_map fmeu1p2_map[] = {
+	{ 0x01, 0x15 }, { 0x02, 0x04 }, { 0x03, 0xb8 }, { 0x04, 0xe3 },
+	{ 0x05, 0x35 }, { 0x06, 0x18 }, { 0x07, 0x7c }, { 0x08, 0x00 },
+	{ 0x09, 0x00 }, { 0x0a, 0x73 }, { 0x0b, 0x40 }, { 0x0c, 0x08 },
+	{ 0x0e, 0x7a }, { 0x0f, 0x88 }, { 0x10, 0x91 }, { 0x11, 0x61 },
+	{ 0x12, 0x61 }, { 0x13, 0x61 }, { 0x14, 0x61 }, { 0x15, 0x5a },
+	{ 0x16, 0x0f }, { 0x17, 0x34 }, { 0x18, 0x1c }, { 0x1a, 0x88 },
+	{ 0x1b, 0x33 }, { 0x1c, 0x02 }, { 0x1d, 0x00 }, { 0x1e, 0x01 },
+	{ 0x23, 0x80 }, { 0x24, 0x00 }, { 0x25, 0x95 }, { 0x26, 0x05 },
+	{ 0x27, 0x2c }, { 0x32, 0x08 }, { 0x33, 0xa8 }, { 0x36, 0x2f },
+	{ 0x37, 0x7e }, { 0x55, 0xbf }, { 0x56, 0x3f }, { 0x57, 0xff },
+	{ 0x58, 0x9f }, { 0x76, 0xac }, { 0x77, 0x40 }, { 0x78, 0x00 },
+	{ 0x79, 0x00 }, { 0x82, 0x47 }, { 0x83, 0x00 }, { 0x85, 0x11 },
+	{ 0x86, 0x3f },
+};
+
+/* FM NA 1.0 settings */
+static const struct max2175_reg_map fmna1p0_map[] = {
+	{ 0x01, 0x13 }, { 0x02, 0x08 }, { 0x03, 0x8d }, { 0x04, 0xc0 },
+	{ 0x05, 0x35 }, { 0x06, 0x18 }, { 0x07, 0x7d }, { 0x08, 0x3f },
+	{ 0x09, 0x7d }, { 0x0a, 0x75 }, { 0x0b, 0x40 }, { 0x0c, 0x08 },
+	{ 0x0e, 0x7a }, { 0x0f, 0x88 }, { 0x10, 0x91 }, { 0x11, 0x61 },
+	{ 0x12, 0x61 }, { 0x13, 0x61 }, { 0x14, 0x61 }, { 0x15, 0x5c },
+	{ 0x16, 0x0f }, { 0x17, 0x34 }, { 0x18, 0x1c }, { 0x1a, 0x88 },
+	{ 0x1b, 0x33 }, { 0x1c, 0x02 }, { 0x1d, 0x00 }, { 0x1e, 0x01 },
+	{ 0x23, 0x80 }, { 0x24, 0x00 }, { 0x25, 0x95 }, { 0x26, 0x05 },
+	{ 0x27, 0x2c }, { 0x32, 0x08 }, { 0x33, 0xa8 }, { 0x36, 0xaf },
+	{ 0x37, 0x7e }, { 0x55, 0xbf }, { 0x56, 0x3f }, { 0x57, 0xff },
+	{ 0x58, 0x9f }, { 0x76, 0xa6 }, { 0x77, 0x40 }, { 0x78, 0x00 },
+	{ 0x79, 0x00 }, { 0x82, 0x35 }, { 0x83, 0x00 }, { 0x85, 0x11 },
+	{ 0x86, 0x3f },
+};
+
+/* FM NA 2.0 settings */
+static const struct max2175_reg_map fmna2p0_map[] = {
+	{ 0x01, 0x13 }, { 0x02, 0x08 }, { 0x03, 0x8d }, { 0x04, 0xc0 },
+	{ 0x05, 0x35 }, { 0x06, 0x18 }, { 0x07, 0x7c }, { 0x08, 0x54 },
+	{ 0x09, 0xa7 }, { 0x0a, 0x55 }, { 0x0b, 0x42 }, { 0x0c, 0x48 },
+	{ 0x0e, 0x7a }, { 0x0f, 0x88 }, { 0x10, 0x91 }, { 0x11, 0x61 },
+	{ 0x12, 0x61 }, { 0x13, 0x61 }, { 0x14, 0x61 }, { 0x15, 0x5c },
+	{ 0x16, 0x0f }, { 0x17, 0x34 }, { 0x18, 0x1c }, { 0x1a, 0x88 },
+	{ 0x1b, 0x33 }, { 0x1c, 0x02 }, { 0x1d, 0x00 }, { 0x1e, 0x01 },
+	{ 0x23, 0x80 }, { 0x24, 0x00 }, { 0x25, 0x95 }, { 0x26, 0x05 },
+	{ 0x27, 0x2c }, { 0x32, 0x08 }, { 0x33, 0xa8 }, { 0x36, 0xaf },
+	{ 0x37, 0x7e }, { 0x55, 0xbf }, { 0x56, 0x3f }, { 0x57, 0xff },
+	{ 0x58, 0x9f }, { 0x76, 0xac }, { 0x77, 0xc0 }, { 0x78, 0x00 },
+	{ 0x79, 0x00 }, { 0x82, 0x6b }, { 0x83, 0x00 }, { 0x85, 0x11 },
+	{ 0x86, 0x3f },
+};
+
+static const u16 ch_coeff_dab1[] = {
+	0x001c, 0x0007, 0xffcd, 0x0056, 0xffa4, 0x0033, 0x0027, 0xff61,
+	0x010e, 0xfec0, 0x0106, 0xffb8, 0xff1c, 0x023c, 0xfcb2, 0x039b,
+	0xfd4e, 0x0055, 0x036a, 0xf7de, 0x0d21, 0xee72, 0x1499, 0x6a51,
+};
+
+static const u16 ch_coeff_fmeu[] = {
+	0x0000, 0xffff, 0x0001, 0x0002, 0xfffa, 0xffff, 0x0015, 0xffec,
+	0xffde, 0x0054, 0xfff9, 0xff52, 0x00b8, 0x00a2, 0xfe0a, 0x00af,
+	0x02e3, 0xfc14, 0xfe89, 0x089d, 0xfa2e, 0xf30f, 0x25be, 0x4eb6,
+};
+
+static const u16 eq_coeff_fmeu1_ra02_m6db[] = {
+	0x0040, 0xffc6, 0xfffa, 0x002c, 0x000d, 0xff90, 0x0037, 0x006e,
+	0xffc0, 0xff5b, 0x006a, 0x00f0, 0xff57, 0xfe94, 0x0112, 0x0252,
+	0xfe0c, 0xfc6a, 0x0385, 0x0553, 0xfa49, 0xf789, 0x0b91, 0x1a10,
+};
+
+static const u16 ch_coeff_fmna[] = {
+	0x0001, 0x0003, 0xfffe, 0xfff4, 0x0000, 0x001f, 0x000c, 0xffbc,
+	0xffd3, 0x007d, 0x0075, 0xff33, 0xff01, 0x0131, 0x01ef, 0xfe60,
+	0xfc7a, 0x020e, 0x0656, 0xfd94, 0xf395, 0x02ab, 0x2857, 0x3d3f,
+};
+
+static const u16 eq_coeff_fmna1_ra02_m6db[] = {
+	0xfff1, 0xffe1, 0xffef, 0x000e, 0x0030, 0x002f, 0xfff6, 0xffa7,
+	0xff9d, 0x000a, 0x00a2, 0x00b5, 0xffea, 0xfed9, 0xfec5, 0x003d,
+	0x0217, 0x021b, 0xff5a, 0xfc2b, 0xfcbd, 0x02c4, 0x0ac3, 0x0e85,
+};
+
+static const u8 adc_presets[2][23] = {
+	{
+		0x83, 0x00, 0xcf, 0xb4, 0x0f, 0x2c, 0x0c, 0x49,
+		0x00, 0x00, 0x00, 0x8c,	0x02, 0x02, 0x00, 0x04,
+		0xec, 0x82, 0x4b, 0xcc, 0x01, 0x88, 0x0c,
+	},
+	{
+		0x83, 0x00, 0xcf, 0xb4,	0x0f, 0x2c, 0x0c, 0x49,
+		0x00, 0x00, 0x00, 0x8c,	0x02, 0x20, 0x33, 0x8c,
+		0x57, 0xd7, 0x59, 0xb7,	0x65, 0x0e, 0x0c,
+	},
+};
+
+/* Tuner bands */
+static const struct v4l2_frequency_band eu_bands_rf = {
+	.tuner = 0,
+	.type = V4L2_TUNER_RF,
+	.index = 0,
+	.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
+	.rangelow   = 65000000,
+	.rangehigh  = 240000000,
+};
+
+static const struct v4l2_frequency_band na_bands_rf = {
+	.tuner = 0,
+	.type = V4L2_TUNER_RF,
+	.index = 0,
+	.capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS,
+	.rangelow   = 65000000,
+	.rangehigh  = 108000000,
+};
+
+/* Regmap settings */
+static const struct regmap_range max2175_regmap_volatile_range[] = {
+	regmap_reg_range(0x30, 0x35),
+	regmap_reg_range(0x3a, 0x45),
+	regmap_reg_range(0x59, 0x5e),
+	regmap_reg_range(0x73, 0x75),
+};
+
+static const struct regmap_access_table max2175_volatile_regs = {
+	.yes_ranges = max2175_regmap_volatile_range,
+	.n_yes_ranges = ARRAY_SIZE(max2175_regmap_volatile_range),
+};
+
+static const struct reg_default max2175_reg_defaults[] = {
+	{ 0x00, 0x07},
+};
+
+static const struct regmap_config max2175_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0xff,
+	.reg_defaults = max2175_reg_defaults,
+	.num_reg_defaults = ARRAY_SIZE(max2175_reg_defaults),
+	.volatile_table = &max2175_volatile_regs,
+	.cache_type = REGCACHE_FLAT,
+};
+
+struct max2175 {
+	struct v4l2_subdev sd;		/* Sub-device */
+	struct i2c_client *client;	/* I2C client */
+
+	/* Controls */
+	struct v4l2_ctrl_handler ctrl_hdl;
+	struct v4l2_ctrl *lna_gain;	/* LNA gain value */
+	struct v4l2_ctrl *if_gain;	/* I/F gain value */
+	struct v4l2_ctrl *pll_lock;	/* PLL lock */
+	struct v4l2_ctrl *i2s_en;	/* I2S output enable */
+	struct v4l2_ctrl *hsls;		/* High-side/Low-side polarity */
+	struct v4l2_ctrl *rx_mode;	/* Receive mode */
+
+	/* Regmap */
+	struct regmap *regmap;
+
+	/* Cached configuration */
+	u32 freq;			/* Tuned freq In Hz */
+	const struct max2175_rxmode *rx_modes;		/* EU or NA modes */
+	const struct v4l2_frequency_band *bands_rf;	/* EU or NA bands */
+
+	/* Device settings */
+	unsigned long xtal_freq;	/* Ref Oscillator freq in Hz */
+	u32 decim_ratio;
+	bool master;			/* Master/Slave */
+	bool am_hiz;			/* AM Hi-Z filter */
+
+	/* ROM values */
+	u8 rom_bbf_bw_am;
+	u8 rom_bbf_bw_fm;
+	u8 rom_bbf_bw_dab;
+
+	/* Driver private variables */
+	bool mode_resolved;		/* Flag to sanity check settings */
+};
+
+static inline struct max2175 *max2175_from_sd(struct v4l2_subdev *sd)
+{
+	return container_of(sd, struct max2175, sd);
+}
+
+static inline struct max2175 *max2175_from_ctrl_hdl(struct v4l2_ctrl_handler *h)
+{
+	return container_of(h, struct max2175, ctrl_hdl);
+}
+
+/* Get bitval of a given val */
+static inline u8 max2175_get_bitval(u8 val, u8 msb, u8 lsb)
+{
+	return (val & GENMASK(msb, lsb)) >> lsb;
+}
+
+/* Read/Write bit(s) on top of regmap */
+static int max2175_read(struct max2175 *ctx, u8 idx, u8 *val)
+{
+	u32 regval;
+	int ret;
+
+	ret = regmap_read(ctx->regmap, idx, &regval);
+	if (ret)
+		mxm_err(ctx, "read ret(%d): idx 0x%02x\n", ret, idx);
+	else
+		*val = regval;
+
+	return ret;
+}
+
+static int max2175_write(struct max2175 *ctx, u8 idx, u8 val)
+{
+	int ret;
+
+	ret = regmap_write(ctx->regmap, idx, val);
+	if (ret)
+		mxm_err(ctx, "write ret(%d): idx 0x%02x val 0x%02x\n",
+			ret, idx, val);
+
+	return ret;
+}
+
+static u8 max2175_read_bits(struct max2175 *ctx, u8 idx, u8 msb, u8 lsb)
+{
+	u8 val;
+
+	if (max2175_read(ctx, idx, &val))
+		return 0;
+
+	return max2175_get_bitval(val, msb, lsb);
+}
+
+static int max2175_write_bits(struct max2175 *ctx, u8 idx,
+			     u8 msb, u8 lsb, u8 newval)
+{
+	int ret = regmap_update_bits(ctx->regmap, idx, GENMASK(msb, lsb),
+				     newval << lsb);
+
+	if (ret)
+		mxm_err(ctx, "wbits ret(%d): idx 0x%02x\n", ret, idx);
+
+	return ret;
+}
+
+static int max2175_write_bit(struct max2175 *ctx, u8 idx, u8 bit, u8 newval)
+{
+	return max2175_write_bits(ctx, idx, bit, bit, newval);
+}
+
+/* Checks expected pattern every msec until timeout */
+static int max2175_poll_timeout(struct max2175 *ctx, u8 idx, u8 msb, u8 lsb,
+				u8 exp_bitval, u32 timeout_us)
+{
+	unsigned int val;
+
+	return regmap_read_poll_timeout(ctx->regmap, idx, val,
+			(max2175_get_bitval(val, msb, lsb) == exp_bitval),
+			1000, timeout_us);
+}
+
+static int max2175_poll_csm_ready(struct max2175 *ctx)
+{
+	int ret;
+
+	ret = max2175_poll_timeout(ctx, 69, 1, 1, 0, 50000);
+	if (ret)
+		mxm_err(ctx, "csm not ready\n");
+
+	return ret;
+}
+
+#define MAX2175_IS_BAND_AM(ctx)		\
+	(max2175_read_bits(ctx, 5, 1, 0) == MAX2175_BAND_AM)
+
+#define MAX2175_IS_BAND_VHF(ctx)	\
+	(max2175_read_bits(ctx, 5, 1, 0) == MAX2175_BAND_VHF)
+
+#define MAX2175_IS_FM_MODE(ctx)		\
+	(max2175_read_bits(ctx, 12, 5, 4) == 0)
+
+#define MAX2175_IS_FMHD_MODE(ctx)	\
+	(max2175_read_bits(ctx, 12, 5, 4) == 1)
+
+#define MAX2175_IS_DAB_MODE(ctx)	\
+	(max2175_read_bits(ctx, 12, 5, 4) == 2)
+
+static int max2175_band_from_freq(u32 freq)
+{
+	if (freq >= 144000 && freq <= 26100000)
+		return MAX2175_BAND_AM;
+	else if (freq >= 65000000 && freq <= 108000000)
+		return MAX2175_BAND_FM;
+
+	return MAX2175_BAND_VHF;
+}
+
+static void max2175_i2s_enable(struct max2175 *ctx, bool enable)
+{
+	if (enable)
+		/* Stuff bits are zeroed */
+		max2175_write_bits(ctx, 104, 3, 0, 2);
+	else
+		/* Keep SCK alive */
+		max2175_write_bits(ctx, 104, 3, 0, 9);
+	mxm_dbg(ctx, "i2s %sabled\n", enable ? "en" : "dis");
+}
+
+static void max2175_set_filter_coeffs(struct max2175 *ctx, u8 m_sel,
+				      u8 bank, const u16 *coeffs)
+{
+	unsigned int i;
+	u8 coeff_addr, upper_address = 24;
+
+	mxm_dbg(ctx, "set_filter_coeffs: m_sel %d bank %d\n", m_sel, bank);
+	max2175_write_bits(ctx, 114, 5, 4, m_sel);
+
+	if (m_sel == 2)
+		upper_address = 12;
+
+	for (i = 0; i < upper_address; i++) {
+		coeff_addr = i + bank * 24;
+		max2175_write(ctx, 115, coeffs[i] >> 8);
+		max2175_write(ctx, 116, coeffs[i]);
+		max2175_write(ctx, 117, coeff_addr | 1 << 7);
+	}
+	max2175_write_bit(ctx, 117, 7, 0);
+}
+
+static void max2175_load_fmeu_1p2(struct max2175 *ctx)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(fmeu1p2_map); i++)
+		max2175_write(ctx, fmeu1p2_map[i].idx, fmeu1p2_map[i].val);
+
+	ctx->decim_ratio = 36;
+
+	/* Load the Channel Filter Coefficients into channel filter bank #2 */
+	max2175_set_filter_coeffs(ctx, MAX2175_CH_MSEL, 0, ch_coeff_fmeu);
+	max2175_set_filter_coeffs(ctx, MAX2175_EQ_MSEL, 0,
+				  eq_coeff_fmeu1_ra02_m6db);
+}
+
+static void max2175_load_dab_1p2(struct max2175 *ctx)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(dab12_map); i++)
+		max2175_write(ctx, dab12_map[i].idx, dab12_map[i].val);
+
+	ctx->decim_ratio = 1;
+
+	/* Load the Channel Filter Coefficients into channel filter bank #2 */
+	max2175_set_filter_coeffs(ctx, MAX2175_CH_MSEL, 2, ch_coeff_dab1);
+}
+
+static void max2175_load_fmna_1p0(struct max2175 *ctx)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(fmna1p0_map); i++)
+		max2175_write(ctx, fmna1p0_map[i].idx, fmna1p0_map[i].val);
+}
+
+static void max2175_load_fmna_2p0(struct max2175 *ctx)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(fmna2p0_map); i++)
+		max2175_write(ctx, fmna2p0_map[i].idx, fmna2p0_map[i].val);
+}
+
+static void max2175_set_bbfilter(struct max2175 *ctx)
+{
+	if (MAX2175_IS_BAND_AM(ctx)) {
+		max2175_write_bits(ctx, 12, 3, 0, ctx->rom_bbf_bw_am);
+		mxm_dbg(ctx, "set_bbfilter AM: rom %d\n", ctx->rom_bbf_bw_am);
+	} else if (MAX2175_IS_DAB_MODE(ctx)) {
+		max2175_write_bits(ctx, 12, 3, 0, ctx->rom_bbf_bw_dab);
+		mxm_dbg(ctx, "set_bbfilter DAB: rom %d\n", ctx->rom_bbf_bw_dab);
+	} else {
+		max2175_write_bits(ctx, 12, 3, 0, ctx->rom_bbf_bw_fm);
+		mxm_dbg(ctx, "set_bbfilter FM: rom %d\n", ctx->rom_bbf_bw_fm);
+	}
+}
+
+static bool max2175_set_csm_mode(struct max2175 *ctx,
+			  enum max2175_csm_mode new_mode)
+{
+	int ret = max2175_poll_csm_ready(ctx);
+
+	if (ret)
+		return ret;
+
+	max2175_write_bits(ctx, 0, 2, 0, new_mode);
+	mxm_dbg(ctx, "set csm new mode %d\n", new_mode);
+
+	/* Wait for a fixed settle down time depending on new mode */
+	switch (new_mode) {
+	case MAX2175_PRESET_TUNE:
+		usleep_range(51100, 51500);	/* 51.1ms */
+		break;
+	/*
+	 * Other mode switches need different sleep values depending on band &
+	 * mode
+	 */
+	default:
+		break;
+	}
+
+	return max2175_poll_csm_ready(ctx);
+}
+
+static int max2175_csm_action(struct max2175 *ctx,
+			      enum max2175_csm_mode action)
+{
+	int ret;
+
+	mxm_dbg(ctx, "csm_action: %d\n", action);
+
+	/* Other actions can be added in future when needed */
+	ret = max2175_set_csm_mode(ctx, MAX2175_LOAD_TO_BUFFER);
+	if (ret)
+		return ret;
+
+	return max2175_set_csm_mode(ctx, MAX2175_PRESET_TUNE);
+}
+
+static int max2175_set_lo_freq(struct max2175 *ctx, u32 lo_freq)
+{
+	u8 lo_mult, loband_bits = 0, vcodiv_bits = 0;
+	u32 int_desired, frac_desired;
+	enum max2175_band band;
+	int ret;
+
+	band = max2175_read_bits(ctx, 5, 1, 0);
+	switch (band) {
+	case MAX2175_BAND_AM:
+		lo_mult = 16;
+		break;
+	case MAX2175_BAND_FM:
+		if (lo_freq <= 74700000) {
+			lo_mult = 16;
+		} else if (lo_freq > 74700000 && lo_freq <= 110000000) {
+			loband_bits = 1;
+			lo_mult = 8;
+		} else {
+			loband_bits = 1;
+			vcodiv_bits = 3;
+			lo_mult = 8;
+		}
+		break;
+	case MAX2175_BAND_VHF:
+		if (lo_freq <= 210000000)
+			vcodiv_bits = 2;
+		else
+			vcodiv_bits = 1;
+
+		loband_bits = 2;
+		lo_mult = 4;
+		break;
+	default:
+		loband_bits = 3;
+		vcodiv_bits = 2;
+		lo_mult = 2;
+		break;
+	}
+
+	if (band == MAX2175_BAND_L)
+		lo_freq /= lo_mult;
+	else
+		lo_freq *= lo_mult;
+
+	int_desired = lo_freq / ctx->xtal_freq;
+	frac_desired = div_u64((u64)(lo_freq % ctx->xtal_freq) << 20,
+			       ctx->xtal_freq);
+
+	/* Check CSM is not busy */
+	ret = max2175_poll_csm_ready(ctx);
+	if (ret)
+		return ret;
+
+	mxm_dbg(ctx, "lo_mult %u int %u  frac %u\n",
+		lo_mult, int_desired, frac_desired);
+
+	/* Write the calculated values to the appropriate registers */
+	max2175_write(ctx, 1, int_desired);
+	max2175_write_bits(ctx, 2, 3, 0, (frac_desired >> 16) & 0xf);
+	max2175_write(ctx, 3, frac_desired >> 8);
+	max2175_write(ctx, 4, frac_desired);
+	max2175_write_bits(ctx, 5, 3, 2, loband_bits);
+	max2175_write_bits(ctx, 6, 7, 6, vcodiv_bits);
+
+	return ret;
+}
+
+/*
+ * Helper similar to DIV_ROUND_CLOSEST but an inline function that accepts s64
+ * dividend and s32 divisor
+ */
+static inline s64 max2175_round_closest(s64 dividend, s32 divisor)
+{
+	if ((dividend > 0 && divisor > 0) || (dividend < 0 && divisor < 0))
+		return div_s64(dividend + divisor / 2, divisor);
+
+	return div_s64(dividend - divisor / 2, divisor);
+}
+
+static int max2175_set_nco_freq(struct max2175 *ctx, s32 nco_freq)
+{
+	s32 clock_rate = ctx->xtal_freq / ctx->decim_ratio;
+	u32 nco_reg, abs_nco_freq = abs(nco_freq);
+	s64 nco_val_desired;
+	int ret;
+
+	if (abs_nco_freq < clock_rate / 2) {
+		nco_val_desired = 2 * nco_freq;
+	} else {
+		nco_val_desired = 2 * (clock_rate - abs_nco_freq);
+		if (nco_freq < 0)
+			nco_val_desired = -nco_val_desired;
+	}
+
+	nco_reg = max2175_round_closest(nco_val_desired << 20, clock_rate);
+
+	if (nco_freq < 0)
+		nco_reg += 0x200000;
+
+	/* Check CSM is not busy */
+	ret = max2175_poll_csm_ready(ctx);
+	if (ret)
+		return ret;
+
+	mxm_dbg(ctx, "freq %d desired %lld reg %u\n",
+		nco_freq, nco_val_desired, nco_reg);
+
+	/* Write the calculated values to the appropriate registers */
+	max2175_write_bits(ctx, 7, 4, 0, (nco_reg >> 16) & 0x1f);
+	max2175_write(ctx, 8, nco_reg >> 8);
+	max2175_write(ctx, 9, nco_reg);
+
+	return ret;
+}
+
+static int max2175_set_rf_freq_non_am_bands(struct max2175 *ctx, u64 freq,
+					    u32 lo_pos)
+{
+	s64 adj_freq, low_if_freq;
+	int ret;
+
+	mxm_dbg(ctx, "rf_freq: non AM bands\n");
+
+	if (MAX2175_IS_FM_MODE(ctx))
+		low_if_freq = 128000;
+	else if (MAX2175_IS_FMHD_MODE(ctx))
+		low_if_freq = 228000;
+	else
+		return max2175_set_lo_freq(ctx, freq);
+
+	if (MAX2175_IS_BAND_VHF(ctx) == (lo_pos == MAX2175_LO_ABOVE_DESIRED))
+		adj_freq = freq + low_if_freq;
+	else
+		adj_freq = freq - low_if_freq;
+
+	ret = max2175_set_lo_freq(ctx, adj_freq);
+	if (ret)
+		return ret;
+
+	return max2175_set_nco_freq(ctx, -low_if_freq);
+}
+
+static int max2175_set_rf_freq(struct max2175 *ctx, u64 freq, u32 lo_pos)
+{
+	int ret;
+
+	if (MAX2175_IS_BAND_AM(ctx))
+		ret = max2175_set_nco_freq(ctx, freq);
+	else
+		ret = max2175_set_rf_freq_non_am_bands(ctx, freq, lo_pos);
+
+	mxm_dbg(ctx, "set_rf_freq: ret %d freq %llu\n", ret, freq);
+
+	return ret;
+}
+
+static int max2175_tune_rf_freq(struct max2175 *ctx, u64 freq, u32 hsls)
+{
+	int ret;
+
+	ret = max2175_set_rf_freq(ctx, freq, hsls);
+	if (ret)
+		return ret;
+
+	ret = max2175_csm_action(ctx, MAX2175_BUFFER_PLUS_PRESET_TUNE);
+	if (ret)
+		return ret;
+
+	mxm_dbg(ctx, "tune_rf_freq: old %u new %llu\n", ctx->freq, freq);
+	ctx->freq = freq;
+
+	return ret;
+}
+
+static void max2175_set_hsls(struct max2175 *ctx, u32 lo_pos)
+{
+	mxm_dbg(ctx, "set_hsls: lo_pos %u\n", lo_pos);
+
+	if ((lo_pos == MAX2175_LO_BELOW_DESIRED) == MAX2175_IS_BAND_VHF(ctx))
+		max2175_write_bit(ctx, 5, 4, 1);
+	else
+		max2175_write_bit(ctx, 5, 4, 0);
+}
+
+static void max2175_set_eu_rx_mode(struct max2175 *ctx, u32 rx_mode)
+{
+	switch (rx_mode) {
+	case MAX2175_EU_FM_1_2:
+		max2175_load_fmeu_1p2(ctx);
+		break;
+
+	case MAX2175_DAB_1_2:
+		max2175_load_dab_1p2(ctx);
+		break;
+	}
+	/* Master is the default setting */
+	if (!ctx->master)
+		max2175_write_bit(ctx, 30, 7, 1);
+}
+
+static void max2175_set_na_rx_mode(struct max2175 *ctx, u32 rx_mode)
+{
+	switch (rx_mode) {
+	case MAX2175_NA_FM_1_0:
+		max2175_load_fmna_1p0(ctx);
+		break;
+	case MAX2175_NA_FM_2_0:
+		max2175_load_fmna_2p0(ctx);
+		break;
+	}
+	/* Master is the default setting */
+	if (!ctx->master)
+		max2175_write_bit(ctx, 30, 7, 1);
+
+	ctx->decim_ratio = 27;
+
+	/* Load the Channel Filter Coefficients into channel filter bank #2 */
+	max2175_set_filter_coeffs(ctx, MAX2175_CH_MSEL, 0, ch_coeff_fmna);
+	max2175_set_filter_coeffs(ctx, MAX2175_EQ_MSEL, 0,
+				  eq_coeff_fmna1_ra02_m6db);
+}
+
+static int max2175_set_rx_mode(struct max2175 *ctx, u32 rx_mode)
+{
+	mxm_dbg(ctx, "set_rx_mode: %u am_hiz %u\n", rx_mode, ctx->am_hiz);
+	if (ctx->xtal_freq == MAX2175_EU_XTAL_FREQ)
+		max2175_set_eu_rx_mode(ctx, rx_mode);
+	else
+		max2175_set_na_rx_mode(ctx, rx_mode);
+
+	if (ctx->am_hiz) {
+		mxm_dbg(ctx, "setting AM HiZ related config\n");
+		max2175_write_bit(ctx, 50, 5, 1);
+		max2175_write_bit(ctx, 90, 7, 1);
+		max2175_write_bits(ctx, 73, 1, 0, 2);
+		max2175_write_bits(ctx, 80, 5, 0, 33);
+	}
+
+	/* Load BB filter trim values saved in ROM */
+	max2175_set_bbfilter(ctx);
+
+	/* Set HSLS */
+	max2175_set_hsls(ctx, ctx->hsls->cur.val);
+
+	/* Use i2s enable settings */
+	max2175_i2s_enable(ctx, ctx->i2s_en->cur.val);
+
+	ctx->mode_resolved = true;
+
+	return 0;
+}
+
+static int max2175_rx_mode_from_freq(struct max2175 *ctx, u32 freq, u32 *mode)
+{
+	unsigned int i;
+	int band = max2175_band_from_freq(freq);
+
+	/* Pick the first match always */
+	for (i = 0; i <= ctx->rx_mode->maximum; i++) {
+		if (ctx->rx_modes[i].band == band) {
+			*mode = i;
+			mxm_dbg(ctx, "rx_mode_from_freq: freq %u mode %d\n",
+				freq, *mode);
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static bool max2175_freq_rx_mode_valid(struct max2175 *ctx,
+					 u32 mode, u32 freq)
+{
+	int band = max2175_band_from_freq(freq);
+
+	return (ctx->rx_modes[mode].band == band);
+}
+
+static void max2175_load_adc_presets(struct max2175 *ctx)
+{
+	unsigned int i, j;
+
+	for (i = 0; i < ARRAY_SIZE(adc_presets); i++)
+		for (j = 0; j < ARRAY_SIZE(adc_presets[0]); j++)
+			max2175_write(ctx, 146 + j + i * 55, adc_presets[i][j]);
+}
+
+static int max2175_init_power_manager(struct max2175 *ctx)
+{
+	int ret;
+
+	/* Execute on-chip power-up/calibration */
+	max2175_write_bit(ctx, 99, 2, 0);
+	usleep_range(1000, 1500);
+	max2175_write_bit(ctx, 99, 2, 1);
+
+	/* Wait for the power manager to finish. */
+	ret = max2175_poll_timeout(ctx, 69, 7, 7, 1, 50000);
+	if (ret)
+		mxm_err(ctx, "init pm failed\n");
+
+	return ret;
+}
+
+static int max2175_recalibrate_adc(struct max2175 *ctx)
+{
+	int ret;
+
+	/* ADC Re-calibration */
+	max2175_write(ctx, 150, 0xff);
+	max2175_write(ctx, 205, 0xff);
+	max2175_write(ctx, 147, 0x20);
+	max2175_write(ctx, 147, 0x00);
+	max2175_write(ctx, 202, 0x20);
+	max2175_write(ctx, 202, 0x00);
+
+	ret = max2175_poll_timeout(ctx, 69, 4, 3, 3, 50000);
+	if (ret)
+		mxm_err(ctx, "adc recalibration failed\n");
+
+	return ret;
+}
+
+static u8 max2175_read_rom(struct max2175 *ctx, u8 row)
+{
+	u8 data = 0;
+
+	max2175_write_bit(ctx, 56, 4, 0);
+	max2175_write_bits(ctx, 56, 3, 0, row);
+
+	usleep_range(2000, 2500);
+	max2175_read(ctx, 58, &data);
+
+	max2175_write_bits(ctx, 56, 3, 0, 0);
+
+	mxm_dbg(ctx, "read_rom: row %d data 0x%02x\n", row, data);
+
+	return data;
+}
+
+static void max2175_load_from_rom(struct max2175 *ctx)
+{
+	u8 data = 0;
+
+	data = max2175_read_rom(ctx, 0);
+	ctx->rom_bbf_bw_am = data & 0x0f;
+	max2175_write_bits(ctx, 81, 3, 0, data >> 4);
+
+	data = max2175_read_rom(ctx, 1);
+	ctx->rom_bbf_bw_fm = data & 0x0f;
+	ctx->rom_bbf_bw_dab = data >> 4;
+
+	data = max2175_read_rom(ctx, 2);
+	max2175_write_bits(ctx, 82, 4, 0, data & 0x1f);
+	max2175_write_bits(ctx, 82, 7, 5, data >> 5);
+
+	data = max2175_read_rom(ctx, 3);
+	if (ctx->am_hiz) {
+		data &= 0x0f;
+		data |= (max2175_read_rom(ctx, 7) & 0x40) >> 2;
+		if (!data)
+			data |= 2;
+	} else {
+		data = (data & 0xf0) >> 4;
+		data |= (max2175_read_rom(ctx, 7) & 0x80) >> 3;
+		if (!data)
+			data |= 30;
+	}
+	max2175_write_bits(ctx, 80, 5, 0, data + 31);
+
+	data = max2175_read_rom(ctx, 6);
+	max2175_write_bits(ctx, 81, 7, 6, data >> 6);
+}
+
+static void max2175_load_full_fm_eu_1p0(struct max2175 *ctx)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(full_fm_eu_1p0); i++)
+		max2175_write(ctx, i + 1, full_fm_eu_1p0[i]);
+
+	usleep_range(5000, 5500);
+	ctx->decim_ratio = 36;
+}
+
+static void max2175_load_full_fm_na_1p0(struct max2175 *ctx)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(full_fm_na_1p0); i++)
+		max2175_write(ctx, i + 1, full_fm_na_1p0[i]);
+
+	usleep_range(5000, 5500);
+	ctx->decim_ratio = 27;
+}
+
+static int max2175_core_init(struct max2175 *ctx, u32 refout_bits)
+{
+	int ret;
+
+	/* MAX2175 uses 36.864MHz clock for EU & 40.154MHz for NA region */
+	if (ctx->xtal_freq == MAX2175_EU_XTAL_FREQ)
+		max2175_load_full_fm_eu_1p0(ctx);
+	else
+		max2175_load_full_fm_na_1p0(ctx);
+
+	/* The default settings assume master */
+	if (!ctx->master)
+		max2175_write_bit(ctx, 30, 7, 1);
+
+	mxm_dbg(ctx, "refout_bits %u\n", refout_bits);
+
+	/* Set REFOUT */
+	max2175_write_bits(ctx, 56, 7, 5, refout_bits);
+
+	/* ADC Reset */
+	max2175_write_bit(ctx, 99, 1, 0);
+	usleep_range(1000, 1500);
+	max2175_write_bit(ctx, 99, 1, 1);
+
+	/* Load ADC preset values */
+	max2175_load_adc_presets(ctx);
+
+	/* Initialize the power management state machine */
+	ret = max2175_init_power_manager(ctx);
+	if (ret)
+		return ret;
+
+	/* Recalibrate ADC */
+	ret = max2175_recalibrate_adc(ctx);
+	if (ret)
+		return ret;
+
+	/* Load ROM values to appropriate registers */
+	max2175_load_from_rom(ctx);
+
+	if (ctx->xtal_freq == MAX2175_EU_XTAL_FREQ) {
+		/* Load FIR coefficients into bank 0 */
+		max2175_set_filter_coeffs(ctx, MAX2175_CH_MSEL, 0,
+					  ch_coeff_fmeu);
+		max2175_set_filter_coeffs(ctx, MAX2175_EQ_MSEL, 0,
+					  eq_coeff_fmeu1_ra02_m6db);
+	} else {
+		/* Load FIR coefficients into bank 0 */
+		max2175_set_filter_coeffs(ctx, MAX2175_CH_MSEL, 0,
+					  ch_coeff_fmna);
+		max2175_set_filter_coeffs(ctx, MAX2175_EQ_MSEL, 0,
+					  eq_coeff_fmna1_ra02_m6db);
+	}
+	mxm_dbg(ctx, "core initialized\n");
+
+	return 0;
+}
+
+static void max2175_s_ctrl_rx_mode(struct max2175 *ctx, u32 rx_mode)
+{
+	/* Load mode. Range check already done */
+	max2175_set_rx_mode(ctx, rx_mode);
+
+	mxm_dbg(ctx, "s_ctrl_rx_mode: %u curr freq %u\n", rx_mode, ctx->freq);
+
+	/* Check if current freq valid for mode & update */
+	if (max2175_freq_rx_mode_valid(ctx, rx_mode, ctx->freq))
+		max2175_tune_rf_freq(ctx, ctx->freq, ctx->hsls->cur.val);
+	else
+		/* Use default freq of mode if current freq is not valid */
+		max2175_tune_rf_freq(ctx, ctx->rx_modes[rx_mode].freq,
+				     ctx->hsls->cur.val);
+}
+
+static int max2175_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct max2175 *ctx = max2175_from_ctrl_hdl(ctrl->handler);
+
+	mxm_dbg(ctx, "s_ctrl: id 0x%x, val %u\n", ctrl->id, ctrl->val);
+	switch (ctrl->id) {
+	case V4L2_CID_MAX2175_I2S_ENABLE:
+		max2175_i2s_enable(ctx, ctrl->val);
+		break;
+	case V4L2_CID_MAX2175_HSLS:
+		max2175_set_hsls(ctx, ctrl->val);
+		break;
+	case V4L2_CID_MAX2175_RX_MODE:
+		max2175_s_ctrl_rx_mode(ctx, ctrl->val);
+		break;
+	}
+
+	return 0;
+}
+
+static u32 max2175_get_lna_gain(struct max2175 *ctx)
+{
+	enum max2175_band band = max2175_read_bits(ctx, 5, 1, 0);
+
+	switch (band) {
+	case MAX2175_BAND_AM:
+		return max2175_read_bits(ctx, 51, 3, 0);
+	case MAX2175_BAND_FM:
+		return max2175_read_bits(ctx, 50, 3, 0);
+	case MAX2175_BAND_VHF:
+		return max2175_read_bits(ctx, 52, 5, 0);
+	default:
+		return 0;
+	}
+}
+
+static int max2175_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct max2175 *ctx = max2175_from_ctrl_hdl(ctrl->handler);
+
+	switch (ctrl->id) {
+	case V4L2_CID_RF_TUNER_LNA_GAIN:
+		ctrl->val = max2175_get_lna_gain(ctx);
+		break;
+	case V4L2_CID_RF_TUNER_IF_GAIN:
+		ctrl->val = max2175_read_bits(ctx, 49, 4, 0);
+		break;
+	case V4L2_CID_RF_TUNER_PLL_LOCK:
+		ctrl->val = (max2175_read_bits(ctx, 60, 7, 6) == 3);
+		break;
+	}
+
+	return 0;
+};
+
+static int max2175_set_freq_and_mode(struct max2175 *ctx, u32 freq)
+{
+	u32 rx_mode;
+	int ret;
+
+	/* Get band from frequency */
+	ret = max2175_rx_mode_from_freq(ctx, freq, &rx_mode);
+	if (ret)
+		return ret;
+
+	mxm_dbg(ctx, "set_freq_and_mode: freq %u rx_mode %d\n", freq, rx_mode);
+
+	/* Load mode */
+	max2175_set_rx_mode(ctx, rx_mode);
+	ctx->rx_mode->cur.val = rx_mode;
+
+	/* Tune to the new freq given */
+	return max2175_tune_rf_freq(ctx, freq, ctx->hsls->cur.val);
+}
+
+static int max2175_s_frequency(struct v4l2_subdev *sd,
+			       const struct v4l2_frequency *vf)
+{
+	struct max2175 *ctx = max2175_from_sd(sd);
+	u32 freq;
+	int ret = 0;
+
+	mxm_dbg(ctx, "s_freq: new %u curr %u, mode_resolved %d\n",
+		vf->frequency, ctx->freq, ctx->mode_resolved);
+
+	if (vf->tuner != 0)
+		return -EINVAL;
+
+	freq = clamp(vf->frequency, ctx->bands_rf->rangelow,
+		     ctx->bands_rf->rangehigh);
+
+	/* Check new freq valid for rx_mode if already resolved */
+	if (ctx->mode_resolved &&
+	    max2175_freq_rx_mode_valid(ctx, ctx->rx_mode->cur.val, freq))
+		ret = max2175_tune_rf_freq(ctx, freq, ctx->hsls->cur.val);
+	else
+		/* Find default rx_mode for freq and tune to it */
+		ret = max2175_set_freq_and_mode(ctx, freq);
+
+	mxm_dbg(ctx, "s_freq: ret %d curr %u mode_resolved %d mode %u\n",
+		ret, ctx->freq, ctx->mode_resolved, ctx->rx_mode->cur.val);
+
+	return ret;
+}
+
+static int max2175_g_frequency(struct v4l2_subdev *sd,
+			       struct v4l2_frequency *vf)
+{
+	struct max2175 *ctx = max2175_from_sd(sd);
+	int ret = 0;
+
+	if (vf->tuner != 0)
+		return -EINVAL;
+
+	/* RF freq */
+	vf->type = V4L2_TUNER_RF;
+	vf->frequency = ctx->freq;
+
+	return ret;
+}
+
+static int max2175_enum_freq_bands(struct v4l2_subdev *sd,
+			    struct v4l2_frequency_band *band)
+{
+	struct max2175 *ctx = max2175_from_sd(sd);
+
+	if (band->tuner != 0 || band->index != 0)
+		return -EINVAL;
+
+	*band = *ctx->bands_rf;
+
+	return 0;
+}
+
+static int max2175_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *vt)
+{
+	struct max2175 *ctx = max2175_from_sd(sd);
+
+	if (vt->index > 0)
+		return -EINVAL;
+
+	strlcpy(vt->name, "RF", sizeof(vt->name));
+	vt->type = V4L2_TUNER_RF;
+	vt->capability = V4L2_TUNER_CAP_1HZ | V4L2_TUNER_CAP_FREQ_BANDS;
+	vt->rangelow = ctx->bands_rf->rangelow;
+	vt->rangehigh = ctx->bands_rf->rangehigh;
+
+	return 0;
+}
+
+static int max2175_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *vt)
+{
+	/* Check tuner index is valid */
+	if (vt->index > 0)
+		return -EINVAL;
+
+	return 0;
+}
+
+static const struct v4l2_subdev_tuner_ops max2175_tuner_ops = {
+	.s_frequency = max2175_s_frequency,
+	.g_frequency = max2175_g_frequency,
+	.enum_freq_bands = max2175_enum_freq_bands,
+	.g_tuner = max2175_g_tuner,
+	.s_tuner = max2175_s_tuner,
+};
+
+static const struct v4l2_subdev_ops max2175_ops = {
+	.tuner = &max2175_tuner_ops,
+};
+
+static const struct v4l2_ctrl_ops max2175_ctrl_ops = {
+	.s_ctrl = max2175_s_ctrl,
+	.g_volatile_ctrl = max2175_g_volatile_ctrl,
+};
+
+/*
+ * I2S output enable/disable configuration. This is a private control.
+ * Refer to Documentation/media/v4l-drivers/max2175 for more details.
+ */
+static const struct v4l2_ctrl_config max2175_i2s_en = {
+	.ops = &max2175_ctrl_ops,
+	.id = V4L2_CID_MAX2175_I2S_ENABLE,
+	.name = "I2S Enable",
+	.type = V4L2_CTRL_TYPE_BOOLEAN,
+	.min = 0,
+	.max = 1,
+	.step = 1,
+	.def = 1,
+	.is_private = 1,
+};
+
+/*
+ * HSLS value control LO freq adjacent location configuration.
+ * Refer to Documentation/media/v4l-drivers/max2175 for more details.
+ */
+static const struct v4l2_ctrl_config max2175_hsls = {
+	.ops = &max2175_ctrl_ops,
+	.id = V4L2_CID_MAX2175_HSLS,
+	.name = "HSLS Above/Below Desired",
+	.type = V4L2_CTRL_TYPE_BOOLEAN,
+	.min = 0,
+	.max = 1,
+	.step = 1,
+	.def = 1,
+};
+
+/*
+ * Rx modes below are a set of preset configurations that decides the tuner's
+ * sck and sample rate of transmission. They are separate for EU & NA regions.
+ * Refer to Documentation/media/v4l-drivers/max2175 for more details.
+ */
+static const char * const max2175_ctrl_eu_rx_modes[] = {
+	[MAX2175_EU_FM_1_2]	= "EU FM 1.2",
+	[MAX2175_DAB_1_2]	= "DAB 1.2",
+};
+
+static const char * const max2175_ctrl_na_rx_modes[] = {
+	[MAX2175_NA_FM_1_0]	= "NA FM 1.0",
+	[MAX2175_NA_FM_2_0]	= "NA FM 2.0",
+};
+
+static const struct v4l2_ctrl_config max2175_eu_rx_mode = {
+	.ops = &max2175_ctrl_ops,
+	.id = V4L2_CID_MAX2175_RX_MODE,
+	.name = "RX Mode",
+	.type = V4L2_CTRL_TYPE_MENU,
+	.max = ARRAY_SIZE(max2175_ctrl_eu_rx_modes) - 1,
+	.def = 0,
+	.qmenu = max2175_ctrl_eu_rx_modes,
+};
+
+static const struct v4l2_ctrl_config max2175_na_rx_mode = {
+	.ops = &max2175_ctrl_ops,
+	.id = V4L2_CID_MAX2175_RX_MODE,
+	.name = "RX Mode",
+	.type = V4L2_CTRL_TYPE_MENU,
+	.max = ARRAY_SIZE(max2175_ctrl_na_rx_modes) - 1,
+	.def = 0,
+	.qmenu = max2175_ctrl_na_rx_modes,
+};
+
+static int max2175_refout_load_to_bits(struct i2c_client *client, u32 load,
+				       u32 *bits)
+{
+	if (load >= 0 && load <= 40)
+		*bits = load / 10;
+	else if (load >= 60 && load <= 70)
+		*bits = load / 10 - 1;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static int max2175_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	bool master = true, am_hiz = false;
+	u32 refout_load, refout_bits = 0;	/* REFOUT disabled */
+	struct v4l2_ctrl_handler *hdl;
+	struct fwnode_handle *fwnode;
+	struct device_node *np;
+	struct v4l2_subdev *sd;
+	struct regmap *regmap;
+	struct max2175 *ctx;
+	struct clk *clk;
+	int ret;
+
+	/* Parse DT properties */
+	np = of_parse_phandle(client->dev.of_node, "maxim,master", 0);
+	if (np) {
+		master = false;			/* Slave tuner */
+		of_node_put(np);
+	}
+
+	fwnode = of_fwnode_handle(client->dev.of_node);
+	if (fwnode_property_present(fwnode, "maxim,am-hiz-filter"))
+		am_hiz = true;
+
+	if (!fwnode_property_read_u32(fwnode, "maxim,refout-load",
+				      &refout_load)) {
+		ret = max2175_refout_load_to_bits(client, refout_load,
+						  &refout_bits);
+		if (ret) {
+			dev_err(&client->dev, "invalid refout_load %u\n",
+				refout_load);
+			return -EINVAL;
+		}
+	}
+
+	clk = devm_clk_get(&client->dev, NULL);
+	if (IS_ERR(clk)) {
+		ret = PTR_ERR(clk);
+		dev_err(&client->dev, "cannot get clock %d\n", ret);
+		return -ENODEV;
+	}
+
+	regmap = devm_regmap_init_i2c(client, &max2175_regmap_config);
+	if (IS_ERR(regmap)) {
+		ret = PTR_ERR(regmap);
+		dev_err(&client->dev, "regmap init failed %d\n", ret);
+		return -ENODEV;
+	}
+
+	/* Alloc tuner context */
+	ctx = devm_kzalloc(&client->dev, sizeof(*ctx), GFP_KERNEL);
+	if (ctx == NULL)
+		return -ENOMEM;
+
+	sd = &ctx->sd;
+	ctx->master = master;
+	ctx->am_hiz = am_hiz;
+	ctx->mode_resolved = false;
+	ctx->regmap = regmap;
+	ctx->xtal_freq = clk_get_rate(clk);
+	dev_info(&client->dev, "xtal freq %luHz\n", ctx->xtal_freq);
+
+	v4l2_i2c_subdev_init(sd, client, &max2175_ops);
+	ctx->client = client;
+
+	sd->flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
+
+	/* Controls */
+	hdl = &ctx->ctrl_hdl;
+	ret = v4l2_ctrl_handler_init(hdl, 7);
+	if (ret)
+		return ret;
+
+	ctx->lna_gain = v4l2_ctrl_new_std(hdl, &max2175_ctrl_ops,
+					  V4L2_CID_RF_TUNER_LNA_GAIN,
+					  0, 63, 1, 0);
+	ctx->lna_gain->flags |= (V4L2_CTRL_FLAG_VOLATILE |
+				 V4L2_CTRL_FLAG_READ_ONLY);
+	ctx->if_gain = v4l2_ctrl_new_std(hdl, &max2175_ctrl_ops,
+					 V4L2_CID_RF_TUNER_IF_GAIN,
+					 0, 31, 1, 0);
+	ctx->if_gain->flags |= (V4L2_CTRL_FLAG_VOLATILE |
+				V4L2_CTRL_FLAG_READ_ONLY);
+	ctx->pll_lock = v4l2_ctrl_new_std(hdl, &max2175_ctrl_ops,
+					  V4L2_CID_RF_TUNER_PLL_LOCK,
+					  0, 1, 1, 0);
+	ctx->pll_lock->flags |= (V4L2_CTRL_FLAG_VOLATILE |
+				 V4L2_CTRL_FLAG_READ_ONLY);
+	ctx->i2s_en = v4l2_ctrl_new_custom(hdl, &max2175_i2s_en, NULL);
+	ctx->hsls = v4l2_ctrl_new_custom(hdl, &max2175_hsls, NULL);
+
+	if (ctx->xtal_freq == MAX2175_EU_XTAL_FREQ) {
+		ctx->rx_mode = v4l2_ctrl_new_custom(hdl,
+						    &max2175_eu_rx_mode, NULL);
+		ctx->rx_modes = eu_rx_modes;
+		ctx->bands_rf = &eu_bands_rf;
+	} else {
+		ctx->rx_mode = v4l2_ctrl_new_custom(hdl,
+						    &max2175_na_rx_mode, NULL);
+		ctx->rx_modes = na_rx_modes;
+		ctx->bands_rf = &na_bands_rf;
+	}
+	ctx->sd.ctrl_handler = &ctx->ctrl_hdl;
+
+	/* Set the defaults */
+	ctx->freq = ctx->bands_rf->rangelow;
+
+	/* Register subdev */
+	ret = v4l2_async_register_subdev(sd);
+	if (ret) {
+		dev_err(&client->dev, "register subdev failed\n");
+		goto err_reg;
+	}
+
+	/* Initialize device */
+	ret = max2175_core_init(ctx, refout_bits);
+	if (ret)
+		goto err_init;
+
+	ret = v4l2_ctrl_handler_setup(hdl);
+	if (ret)
+		goto err_init;
+
+	return 0;
+
+err_init:
+	v4l2_async_unregister_subdev(sd);
+err_reg:
+	v4l2_ctrl_handler_free(&ctx->ctrl_hdl);
+
+	return ret;
+}
+
+static int max2175_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct max2175 *ctx = max2175_from_sd(sd);
+
+	v4l2_ctrl_handler_free(&ctx->ctrl_hdl);
+	v4l2_async_unregister_subdev(sd);
+
+	return 0;
+}
+
+static const struct i2c_device_id max2175_id[] = {
+	{ DRIVER_NAME, 0},
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, max2175_id);
+
+static const struct of_device_id max2175_of_ids[] = {
+	{ .compatible = "maxim,max2175", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, max2175_of_ids);
+
+static struct i2c_driver max2175_driver = {
+	.driver = {
+		.name	= DRIVER_NAME,
+		.of_match_table = max2175_of_ids,
+	},
+	.probe		= max2175_probe,
+	.remove		= max2175_remove,
+	.id_table	= max2175_id,
+};
+
+module_i2c_driver(max2175_driver);
+
+MODULE_DESCRIPTION("Maxim MAX2175 RF to Bits tuner driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Ramesh Shanmugasundaram <[e-mail]>");

drivers/media/i2c/max2175.h

···
+/*
+ * Maxim Integrated MAX2175 RF to Bits tuner driver
+ *
+ * This driver & most of the hard coded values are based on the reference
+ * application delivered by Maxim for this device.
+ *
+ * Copyright (C) 2016 Maxim Integrated Products
+ * Copyright (C) 2017 Renesas Electronics Corporation
+ *
+ * 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.
+ *
+ * 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.
+ */
+
+#ifndef __MAX2175_H__
+#define __MAX2175_H__
+
+#define MAX2175_EU_XTAL_FREQ	36864000	/* In Hz */
+#define MAX2175_NA_XTAL_FREQ	40186125	/* In Hz */
+
+enum max2175_region {
+	MAX2175_REGION_EU = 0,	/* Europe */
+	MAX2175_REGION_NA,	/* North America */
+};
+
+enum max2175_band {
+	MAX2175_BAND_AM = 0,
+	MAX2175_BAND_FM,
+	MAX2175_BAND_VHF,
+	MAX2175_BAND_L,
+};
+
+enum max2175_eu_mode {
+	/* EU modes */
+	MAX2175_EU_FM_1_2 = 0,
+	MAX2175_DAB_1_2,
+
+	/*
+	 * Other possible modes to add in future
+	 * MAX2175_DAB_1_0,
+	 * MAX2175_DAB_1_3,
+	 * MAX2175_EU_FM_2_2,
+	 * MAX2175_EU_FMHD_4_0,
+	 * MAX2175_EU_AM_1_0,
+	 * MAX2175_EU_AM_2_2,
+	 */
+};
+
+enum max2175_na_mode {
+	/* NA modes */
+	MAX2175_NA_FM_1_0 = 0,
+	MAX2175_NA_FM_2_0,
+
+	/*
+	 * Other possible modes to add in future
+	 * MAX2175_NA_FMHD_1_0,
+	 * MAX2175_NA_FMHD_1_2,
+	 * MAX2175_NA_AM_1_0,
+	 * MAX2175_NA_AM_1_2,
+	 */
+};
+
+/* Supported I2S modes */
+enum {
+	MAX2175_I2S_MODE0 = 0,
+	MAX2175_I2S_MODE1,
+	MAX2175_I2S_MODE2,
+	MAX2175_I2S_MODE3,
+	MAX2175_I2S_MODE4,
+};
+
+/* Coefficient table groups */
+enum {
+	MAX2175_CH_MSEL = 0,
+	MAX2175_EQ_MSEL,
+	MAX2175_AA_MSEL,
+};
+
+/* HSLS LO injection polarity */
+enum {
+	MAX2175_LO_BELOW_DESIRED = 0,
+	MAX2175_LO_ABOVE_DESIRED,
+};
+
+/* Channel FSM modes */
+enum max2175_csm_mode {
+	MAX2175_LOAD_TO_BUFFER = 0,
+	MAX2175_PRESET_TUNE,
+	MAX2175_SEARCH,
+	MAX2175_AF_UPDATE,
+	MAX2175_JUMP_FAST_TUNE,
+	MAX2175_CHECK,
+	MAX2175_LOAD_AND_SWAP,
+	MAX2175_END,
+	MAX2175_BUFFER_PLUS_PRESET_TUNE,
+	MAX2175_BUFFER_PLUS_SEARCH,
+	MAX2175_BUFFER_PLUS_AF_UPDATE,
+	MAX2175_BUFFER_PLUS_JUMP_FAST_TUNE,
+	MAX2175_BUFFER_PLUS_CHECK,
+	MAX2175_BUFFER_PLUS_LOAD_AND_SWAP,
+	MAX2175_NO_ACTION
+};
+
+#endif /* __MAX2175_H__ */

include/uapi/linux/max2175.h

···
+/*
+ * max2175.h
+ *
+ * Maxim Integrated MAX2175 RF to Bits tuner driver - user space header file.
+ *
+ * Copyright (C) 2016 Maxim Integrated Products
+ * Copyright (C) 2017 Renesas Electronics Corporation
+ *
+ * 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.
+ *
+ * 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.
+ */
+
+#ifndef __UAPI_MAX2175_H_
+#define __UAPI_MAX2175_H_
+
+#include <linux/v4l2-controls.h>
+
+#define V4L2_CID_MAX2175_I2S_ENABLE	(V4L2_CID_USER_MAX217X_BASE + 0x01)
+#define V4L2_CID_MAX2175_HSLS		(V4L2_CID_USER_MAX217X_BASE + 0x02)
+#define V4L2_CID_MAX2175_RX_MODE	(V4L2_CID_USER_MAX217X_BASE + 0x03)
+
+#endif /* __UAPI_MAX2175_H_ */