@@ -0,0 +1,836 @@
+// SPDX-License-Identifier: GPL-2.0
+/* 8t49n24x-core.c - Program 8T49N24x settings via I2C (common code)
+ *
+ * Copyright (C) 2018, Renesas Electronics America <david.cater.jc@renesas.com>
+ */
+
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+
+#include "8t49n24x-core.h"
+
+/*
+ * In Timing Commander, Q0 is changed from 25MHz to Q0 75MHz, the following
+ * changes occur:
+ *
+ * 2 bytes change in EEPROM data string.
+ *
+ * DSM_INT R0025[0],R0026[7:0] : 35 => 30
+ * NS2_Q0 R0040[7:0],R0041[7:0] : 14 => 4
+ *
+ * In EEPROM
+ * 1. R0026
+ * 2. R0041
+ *
+ * Note that VCO_Frequency (metadata) also changed (3500 =>3000).
+ * This reflects a change to DSM_INT.
+ *
+ * Note that the Timing Commander code has workarounds in the workflow scripts
+ * to handle dividers for the 8T49N241 (because the development of that GUI
+ * predates chip override functionality). That affects NS1_Qx (x in 1-3)
+ * and NS2_Qx. NS1_Qx contains the upper bits of NS_Qx, and NS2_Qx contains
+ * the lower bits. That is NOT the case for Q0, though. In that case NS1_Q0
+ * is the 1st stage output divider (/5, /6, /4) and NS2_Q0 is the 16-bit
+ * second stage (with actual divide being twice the value stored in the
+ * register).
+ *
+ * NS1_Q0 R003F[1:0]
+ */
+
+#define RENESAS24X_VCO_MIN 2999997000u
+#define RENESAS24X_VCO_MAX 4000004000u
+#define RENESAS24X_VCO_OPT 3500000000u
+#define RENESAS24X_MIN_INT_DIVIDER 6
+#define RENESAS24X_MIN_NS1 4
+#define RENESAS24X_MAX_NS1 6
+
+static u8 q0_ns1_options[3] = { 5, 6, 4 };
+
+/**
+ * __renesas_bits_to_shift - num bits to shift given specified mask
+ * @mask: 32-bit word input to count zero bits on right
+ *
+ * Given a bit mask indicating where a value will be stored in
+ * a register, return the number of bits you need to shift the value
+ * before ORing it into the register value.
+ *
+ * Return: number of bits to shift
+ */
+int __renesas_bits_to_shift(unsigned int mask)
+{
+ /* the number of zero bits on the right */
+ unsigned int c = 32;
+
+ mask &= ~mask + 1;
+ if (mask)
+ c--;
+ if (mask & 0x0000FFFF)
+ c -= 16;
+ if (mask & 0x00FF00FF)
+ c -= 8;
+ if (mask & 0x0F0F0F0F)
+ c -= 4;
+ if (mask & 0x33333333)
+ c -= 2;
+ if (mask & 0x55555555)
+ c -= 1;
+ return c;
+}
+
+/*
+ * TODO: Consider replacing this with regmap_multi_reg_write, which
+ * supports introducing a delay after each write. Experiment to see if
+ * the writes succeed consistently when using that API.
+ */
+static int regmap_bulk_write_with_retry(struct regmap *map, unsigned int offset,
+ u8 *val, int val_count,
+ int max_attempts)
+{
+ int err = 0, count = 1;
+
+ do {
+ err = regmap_bulk_write(map, offset, val, val_count);
+ if (err == 0)
+ return 0;
+ usleep_range(100, 200);
+ } while (count++ <= max_attempts);
+ return err;
+}
+
+static int regmap_write_with_retry(struct regmap *map, unsigned int offset,
+ unsigned int val, int max_attempts)
+{
+ int err = 0, count = 1;
+
+ do {
+ err = regmap_write(map, offset, val);
+ if (err == 0)
+ return 0;
+ usleep_range(100, 200);
+ } while (count++ <= max_attempts);
+ return err;
+}
+
+/*
+ * TODO: Consider using regmap_multi_reg_write instead. Explore
+ * use of regmap to configure WRITE_BLOCK_SIZE, and using the delay
+ * mechanism in regmap_multi_reg_write instead of retrying multiple
+ * times (regmap_bulk_write_with_retry).
+ */
+int __renesas_i2c_write_bulk(struct i2c_client *client, struct regmap *map,
+ unsigned int reg, u8 val[], size_t val_count)
+{
+ char dbg[128];
+ u8 block[WRITE_BLOCK_SIZE];
+ unsigned int block_offset = reg;
+ int x = 0, err = 0, currentOffset = 0;
+
+ dev_dbg(&client->dev,
+ "I2C->0x%04x : [hex] . First byte: %02x, Second byte: %02x",
+ reg, reg >> 8, reg & 0xFF);
+
+ dbg[0] = 0;
+
+ for (x = 0; x < val_count; x++) {
+ char data[4];
+
+ block[currentOffset++] = val[x];
+ sprintf(data, "%02x ", val[x]);
+ strcat(dbg, data);
+ if (x > 0 && (x + 1) % WRITE_BLOCK_SIZE == 0) {
+ dev_dbg(&client->dev, "%s", dbg);
+ dbg[0] = '\0';
+ sprintf(dbg,
+ "(loop) calling regmap_bulk_write @ 0x%04x [%d bytes]",
+ block_offset, WRITE_BLOCK_SIZE);
+ dev_dbg(&client->dev, "%s", dbg);
+ dbg[0] = '\0';
+ err = regmap_bulk_write_with_retry(map, block_offset, block,
+ WRITE_BLOCK_SIZE, 5);
+ if (err)
+ break;
+ block_offset += WRITE_BLOCK_SIZE;
+ currentOffset = 0;
+ }
+ }
+ if (err == 0 && currentOffset > 0) {
+ dev_dbg(&client->dev, "%s", dbg);
+ dev_dbg(&client->dev,
+ "(final) calling regmap_bulk_write @ 0x%04x [%d bytes]",
+ block_offset, currentOffset);
+ err = regmap_bulk_write_with_retry(map, block_offset, block, currentOffset, 5);
+ }
+
+ return err;
+}
+
+static int __i2c_write(struct i2c_client *client, struct regmap *map,
+ unsigned int reg, unsigned int val)
+{
+ int err = 0;
+
+ dev_dbg(&client->dev, "I2C->0x%x : [hex] %x", reg, val);
+ err = regmap_write_with_retry(map, reg, val, 5);
+ usleep_range(100, 200);
+ return err;
+}
+
+static int __i2c_write_with_mask(struct i2c_client *client, struct regmap *map,
+ unsigned int reg, u8 val, u8 original, u8 mask)
+{
+ return __i2c_write(client, map, reg,
+ ((val << __renesas_bits_to_shift(mask)) & mask) | (original & ~mask));
+}
+
+int renesas24x_get_offsets(u8 output_num, struct clk_register_offsets *offsets)
+{
+ switch (output_num) {
+ case 0:
+ offsets->oe_offset = RENESAS24X_REG_OUTEN;
+ offsets->oe_mask = RENESAS24X_REG_OUTEN0_MASK;
+ offsets->dis_mask = RENESAS24X_REG_Q0_DIS_MASK;
+ offsets->ns1_offset = RENESAS24X_REG_NS1_Q0;
+ offsets->ns1_offset_mask = RENESAS24X_REG_NS1_Q0_MASK;
+ offsets->ns2_15_8_offset = RENESAS24X_REG_NS2_Q0_15_8;
+ offsets->ns2_7_0_offset = RENESAS24X_REG_NS2_Q0_7_0;
+ break;
+ case 1:
+ offsets->oe_offset = RENESAS24X_REG_OUTEN;
+ offsets->oe_mask = RENESAS24X_REG_OUTEN1_MASK;
+ offsets->dis_mask = RENESAS24X_REG_Q1_DIS_MASK;
+ offsets->n_17_16_offset = RENESAS24X_REG_N_Q1_17_16;
+ offsets->n_17_16_mask = RENESAS24X_REG_N_Q1_17_16_MASK;
+ offsets->n_15_8_offset = RENESAS24X_REG_N_Q1_15_8;
+ offsets->n_7_0_offset = RENESAS24X_REG_N_Q1_7_0;
+ offsets->nfrac_27_24_offset = RENESAS24X_REG_NFRAC_Q1_27_24;
+ offsets->nfrac_27_24_mask = RENESAS24X_REG_NFRAC_Q1_27_24_MASK;
+ offsets->nfrac_23_16_offset = RENESAS24X_REG_NFRAC_Q1_23_16;
+ offsets->nfrac_15_8_offset = RENESAS24X_REG_NFRAC_Q1_15_8;
+ offsets->nfrac_7_0_offset = RENESAS24X_REG_NFRAC_Q1_7_0;
+ break;
+ case 2:
+ offsets->oe_offset = RENESAS24X_REG_OUTEN;
+ offsets->oe_mask = RENESAS24X_REG_OUTEN2_MASK;
+ offsets->dis_mask = RENESAS24X_REG_Q2_DIS_MASK;
+ offsets->n_17_16_offset = RENESAS24X_REG_N_Q2_17_16;
+ offsets->n_17_16_mask = RENESAS24X_REG_N_Q2_17_16_MASK;
+ offsets->n_15_8_offset = RENESAS24X_REG_N_Q2_15_8;
+ offsets->n_7_0_offset = RENESAS24X_REG_N_Q2_7_0;
+ offsets->nfrac_27_24_offset = RENESAS24X_REG_NFRAC_Q2_27_24;
+ offsets->nfrac_27_24_mask = RENESAS24X_REG_NFRAC_Q2_27_24_MASK;
+ offsets->nfrac_23_16_offset = RENESAS24X_REG_NFRAC_Q2_23_16;
+ offsets->nfrac_15_8_offset = RENESAS24X_REG_NFRAC_Q2_15_8;
+ offsets->nfrac_7_0_offset = RENESAS24X_REG_NFRAC_Q2_7_0;
+ break;
+ case 3:
+ offsets->oe_offset = RENESAS24X_REG_OUTEN;
+ offsets->oe_mask = RENESAS24X_REG_OUTEN3_MASK;
+ offsets->dis_mask = RENESAS24X_REG_Q3_DIS_MASK;
+ offsets->n_17_16_offset = RENESAS24X_REG_N_Q3_17_16;
+ offsets->n_17_16_mask = RENESAS24X_REG_N_Q3_17_16_MASK;
+ offsets->n_15_8_offset = RENESAS24X_REG_N_Q3_15_8;
+ offsets->n_7_0_offset = RENESAS24X_REG_N_Q3_7_0;
+ offsets->nfrac_27_24_offset = RENESAS24X_REG_NFRAC_Q3_27_24;
+ offsets->nfrac_27_24_mask = RENESAS24X_REG_NFRAC_Q3_27_24_MASK;
+ offsets->nfrac_23_16_offset = RENESAS24X_REG_NFRAC_Q3_23_16;
+ offsets->nfrac_15_8_offset = RENESAS24X_REG_NFRAC_Q3_15_8;
+ offsets->nfrac_7_0_offset = RENESAS24X_REG_NFRAC_Q3_7_0;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * renesas24x_calc_div_q0 - Calculate dividers and VCO freq to generate
+ * the specified Q0 frequency.
+ * @chip: Device data structure. contains all requested frequencies
+ * for all outputs.
+ *
+ * The actual output divider is ns1 * ns2 * 2. fOutput = fVCO / (ns1 * ns2 * 2)
+ *
+ * The options for ns1 (when the source is the VCO) are 4,5,6. ns2 is a
+ * 16-bit value.
+ *
+ * chip->divs: structure for specifying ns1/ns2 values. If 0 after this
+ * function, Q0 is not requested
+ *
+ * Return: 0 on success, negative errno otherwise.
+ */
+static int renesas24x_calc_div_q0(struct clk_renesas24x_chip *chip)
+{
+ u8 x = 0;
+ u32 min_div = 0, max_div = 0, best_vco = 0;
+ u16 min_ns2 = 0, max_ns2 = 0;
+ bool is_lower_vco = false;
+
+ chip->divs.ns1_q0 = 0;
+ chip->divs.ns2_q0 = 0;
+
+ if (chip->clk[0].requested == 0)
+ return 0;
+
+ min_div = div64_u64((u64)RENESAS24X_VCO_MIN, chip->clk[0].requested * 2) * 2;
+ max_div = div64_u64((u64)RENESAS24X_VCO_MAX, chip->clk[0].requested * 2) * 2;
+
+ dev_dbg(&chip->i2c_client->dev,
+ "requested: %u, min_div: %u, max_div: %u",
+ chip->clk[0].requested, min_div, max_div);
+
+ min_ns2 = div64_u64((u64)min_div, RENESAS24X_MAX_NS1 * 2);
+ max_ns2 = div64_u64((u64)max_div, RENESAS24X_MIN_NS1 * 2);
+
+ dev_dbg(&chip->i2c_client->dev, "min_ns2: %u, max_ns2: %u", min_ns2, max_ns2);
+
+ for (x = 0; x < ARRAY_SIZE(q0_ns1_options); x++) {
+ u16 y = min_ns2;
+
+ while (y <= max_ns2) {
+ u32 actual_div = q0_ns1_options[x] * y * 2;
+ u32 current_vco = actual_div * chip->clk[0].requested;
+
+ if (current_vco < RENESAS24X_VCO_MIN)
+ dev_dbg(&chip->i2c_client->dev,
+ "ignore div: (ns1=%u * ns2=%u * 2 * %u) == %u < %u",
+ q0_ns1_options[x], y,
+ chip->clk[0].requested, current_vco,
+ RENESAS24X_VCO_MIN);
+ else if (current_vco > RENESAS24X_VCO_MAX) {
+ dev_dbg(&chip->i2c_client->dev,
+ "ignore div: (ns1=%u * ns2=%u * 2 * %u) == %u > %u. EXIT LOOP.",
+ q0_ns1_options[x], y,
+ chip->clk[0].requested, current_vco,
+ RENESAS24X_VCO_MAX);
+ y = max_ns2;
+ } else {
+ bool use = false;
+
+ dev_dbg(&chip->i2c_client->dev,
+ "contender: (ns1=%u * ns2=%u * 2 * %u) == %u [in range]",
+ q0_ns1_options[x], y,
+ chip->clk[0].requested, current_vco);
+ if (current_vco <= RENESAS24X_VCO_OPT) {
+ if (current_vco > best_vco || !is_lower_vco) {
+ is_lower_vco = true;
+ use = true;
+ }
+ } else if (!is_lower_vco && current_vco > best_vco) {
+ use = true;
+ }
+ if (use) {
+ chip->divs.ns1_q0 = x;
+ chip->divs.ns2_q0 = y;
+ best_vco = current_vco;
+ }
+ }
+ y++;
+ }
+ }
+
+ dev_dbg(&chip->i2c_client->dev,
+ "best: (ns1=%u [/%u] * ns2=%u * 2 * %u) == %u",
+ chip->divs.ns1_q0, q0_ns1_options[chip->divs.ns1_q0],
+ chip->divs.ns2_q0, chip->clk[0].requested, best_vco);
+ return 0;
+}
+
+/**
+ * renesas24x_calc_divs - Calculate dividers to generate the specified frequency.
+ * @chip: Device data structure. contains all requested frequencies
+ * for all outputs.
+ *
+ * Calculate the clock dividers (dsmint, dsmfrac for vco; ns1/ns2 for q0,
+ * n/nfrac for q1-3) for a given target frequency.
+ *
+ * Return: 0 on success, negative errno otherwise.
+ */
+static int renesas24x_calc_divs(struct clk_renesas24x_chip *chip)
+{
+ u32 vco = 0;
+ int result = 0;
+
+ result = renesas24x_calc_div_q0(chip);
+ if (result < 0)
+ return result;
+
+ dev_dbg(&chip->i2c_client->dev,
+ "after renesas24x_calc_div_q0. ns1: %u [/%u], ns2: %u",
+ chip->divs.ns1_q0, q0_ns1_options[chip->divs.ns1_q0],
+ chip->divs.ns2_q0);
+
+ chip->divs.dsmint = 0;
+ chip->divs.dsmfrac = 0;
+
+ if (chip->clk[0].requested > 0) {
+ /* Q0 is in use and is governing the actual VCO freq */
+ vco = q0_ns1_options[chip->divs.ns1_q0] * chip->divs.ns2_q0
+ * 2 * chip->clk[0].requested;
+ } else {
+ u32 freq = 0;
+ u32 walk = 0;
+ u32 min_div = 0, max_div = 0;
+ bool is_lower_vco = false;
+
+ /*
+ * Q0 is not in use. Use the first requested (fractional)
+ * output frequency as the one controlling the VCO.
+ */
+ for (walk = 1; walk < NUM_OUTPUTS; walk++) {
+ if (chip->clk[walk].requested != 0) {
+ freq = chip->clk[walk].requested;
+ break;
+ }
+ }
+
+ if (freq == 0) {
+ dev_err(&chip->i2c_client->dev, "NO FREQUENCIES SPECIFIED");
+ return -EINVAL;
+ }
+
+ /*
+ * First, determine the min/max div for the output frequency.
+ */
+ min_div = RENESAS24X_MIN_INT_DIVIDER;
+ max_div = div64_u64((u64)RENESAS24X_VCO_MAX, freq * 2) * 2;
+
+ dev_dbg(&chip->i2c_client->dev,
+ "calc_divs for fractional output. freq: %u, min_div: %u, max_div: %u",
+ freq, min_div, max_div);
+
+ walk = min_div;
+
+ while (walk <= max_div) {
+ u32 current_vco = freq * walk;
+
+ dev_dbg(&chip->i2c_client->dev,
+ "calc_divs for fractional output. walk: %u, freq: %u, vco: %u",
+ walk, freq, vco);
+ if (current_vco >= RENESAS24X_VCO_MIN &&
+ vco <= RENESAS24X_VCO_MAX) {
+ if (current_vco <= RENESAS24X_VCO_OPT) {
+ if (current_vco > vco || !is_lower_vco) {
+ is_lower_vco = true;
+ vco = current_vco;
+ }
+ } else if (!is_lower_vco && current_vco > vco) {
+ vco = current_vco;
+ }
+ }
+ /* Divider must be even. */
+ walk += 2;
+ }
+ }
+
+ if (vco != 0) {
+ u32 pfd = 0;
+ u64 rem = 0;
+ int x = 0;
+
+ /* Setup dividers for outputs with fractional dividers. */
+ for (x = 1; x < NUM_OUTPUTS; x++) {
+ if (chip->clk[x].requested != 0) {
+ /*
+ * The value written to the chip is half
+ * the calculated divider.
+ */
+ chip->divs.nint[x - 1] = div64_u64_rem((u64)vco,
+ chip->clk[x].requested * 2,
+ &rem);
+ chip->divs.nfrac[x - 1] = div64_u64(rem * 1 << 28,
+ chip->clk[x].requested * 2);
+ dev_dbg(&chip->i2c_client->dev,
+ "div to get Q%i freq %u from vco %u: int part: %u, rem: %llu, frac part: %u",
+ x, chip->clk[x].requested,
+ vco, chip->divs.nint[x - 1], rem,
+ chip->divs.nfrac[x - 1]);
+ }
+ }
+
+ /* Calculate freq for pfd */
+ pfd = chip->input_clk_freq * (chip->doubler_disabled ? 1 : 2);
+
+ /*
+ * Calculate dsmint & dsmfrac:
+ * -----------------------------
+ * dsm = float(vco)/float(pfd)
+ * dsmfrac = dsm-floor(dsm) * 2^21
+ * rem = vco % pfd
+ * therefore:
+ * dsmfrac = (rem * 2^21)/pfd
+ */
+ chip->divs.dsmint = div64_u64_rem(vco, pfd, &rem);
+ chip->divs.dsmfrac = div64_u64(rem * 1 << 21, pfd);
+
+ dev_dbg(&chip->i2c_client->dev,
+ "vco: %u, pfd: %u, dsmint: %u, dsmfrac: %u, rem: %llu",
+ vco, pfd, chip->divs.dsmint,
+ chip->divs.dsmfrac, rem);
+ } else {
+ dev_err(&chip->i2c_client->dev, "no integer divider in range found. NOT SUPPORTED.");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * renesas24x_enable_output - Enable/disable a particular output
+ * @chip: Device data structure
+ * @output: Output to enable/disable
+ * @enable: Enable (true/false)
+ *
+ * Return: passes on regmap_write return value.
+ */
+static int renesas24x_enable_output(struct clk_renesas24x_chip *chip, u8 output,
+ bool enable)
+{
+ int err = 0;
+ struct clk_register_offsets offsets;
+ struct i2c_client *client = chip->i2c_client;
+
+ /*
+ * When an output is enabled, enable it in the original
+ * data read from the chip and cached. Otherwise it may be
+ * accidentally turned off when another output is enabled.
+ *
+ * E.g., the driver starts with all outputs off in reg_out_en_x.
+ * Q1 is enabled with the appropriate mask. Q2 is then enabled,
+ * which results in Q1 being turned back off (because Q1 was off
+ * in reg_out_en_x).
+ */
+
+ err = renesas24x_get_offsets(output, &offsets);
+ if (err) {
+ dev_err(&client->dev, "error calling renesas24x_get_offsets for %d: %i",
+ output, err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "q%u enable? %d. reg_out_en_x before: 0x%x, reg_out_mode_0_1 before: 0x%x",
+ output, enable, chip->reg_out_en_x, chip->reg_out_mode_0_1);
+
+ dev_dbg(&client->dev, "reg_out_mode_2_3 before: 0x%x, reg_qx_dis before: 0x%x",
+ chip->reg_out_mode_2_3, chip->reg_qx_dis);
+
+ chip->reg_out_en_x = chip->reg_out_en_x & ~offsets.oe_mask;
+ if (enable)
+ chip->reg_out_en_x |= (1 << __renesas_bits_to_shift(offsets.oe_mask));
+
+ chip->reg_qx_dis = chip->reg_qx_dis & ~offsets.dis_mask;
+ dev_dbg(&client->dev,
+ "q%u enable? %d. reg_qx_dis mask: 0x%x, before checking enable: 0x%x",
+ output, enable, offsets.dis_mask, chip->reg_qx_dis);
+
+ if (!enable)
+ chip->reg_qx_dis |= (1 << __renesas_bits_to_shift(offsets.dis_mask));
+
+ dev_dbg(&client->dev,
+ "q%u enable? %d. reg_out_en_x after: 0x%x, reg_qx_dis after: 0x%x",
+ output, enable, chip->reg_out_en_x, chip->reg_qx_dis);
+
+ err = __i2c_write(client, chip->regmap, RENESAS24X_REG_OUTEN, chip->reg_out_en_x);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_OUTEN: %i", err);
+ return err;
+ }
+
+ err = __i2c_write(client, chip->regmap, RENESAS24X_REG_OUTMODE0_1, chip->reg_out_mode_0_1);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_OUTMODE0_1: %i", err);
+ return err;
+ }
+
+ err = __i2c_write(client, chip->regmap, RENESAS24X_REG_OUTMODE2_3, chip->reg_out_mode_2_3);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_OUTMODE2_3: %i", err);
+ return err;
+ }
+
+ err = __i2c_write(client, chip->regmap, RENESAS24X_REG_Q_DIS, chip->reg_qx_dis);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_Q_DIS: %i", err);
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * renesas24x_update_device - write registers to the chip
+ * @chip: Device data structure
+ *
+ * Write all values to hardware that we have calculated.
+ *
+ * Return: passes on regmap_bulk_write return value.
+ */
+static int renesas24x_update_device(struct clk_renesas24x_chip *chip)
+{
+ int err = 0, x = -1;
+ struct i2c_client *client = chip->i2c_client;
+
+ dev_dbg(&client->dev, "setting DSM_INT_8 (val %u @ %u)",
+ chip->divs.dsmint >> 8, RENESAS24X_REG_DSM_INT_8);
+
+ err = __i2c_write_with_mask(client, chip->regmap, RENESAS24X_REG_DSM_INT_8,
+ (chip->divs.dsmint >> 8) & RENESAS24X_REG_DSM_INT_8_MASK,
+ chip->reg_dsm_int_8, RENESAS24X_REG_DSM_INT_8_MASK);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_DSM_INT_8: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev, "setting DSM_INT_7_0 (val %u @ 0x%x)",
+ chip->divs.dsmint & 0xFF, RENESAS24X_REG_DSM_INT_7_0);
+
+ err = __i2c_write(client, chip->regmap, RENESAS24X_REG_DSM_INT_7_0,
+ chip->divs.dsmint & 0xFF);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_DSM_INT_7_0: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting RENESAS24X_REG_DSMFRAC_20_16 (val %u @ 0x%x)",
+ chip->divs.dsmfrac >> 16,
+ RENESAS24X_REG_DSMFRAC_20_16);
+
+ err = __i2c_write_with_mask(client, chip->regmap, RENESAS24X_REG_DSMFRAC_20_16,
+ (chip->divs.dsmfrac >> 16) & RENESAS24X_REG_DSMFRAC_20_16_MASK,
+ chip->reg_dsm_int_8, RENESAS24X_REG_DSMFRAC_20_16_MASK);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_DSMFRAC_20_16: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting RENESAS24X_REG_DSMFRAC_15_8 (val %u @ 0x%x)",
+ (chip->divs.dsmfrac >> 8) & 0xFF,
+ RENESAS24X_REG_DSMFRAC_15_8);
+
+ err = __i2c_write(client, chip->regmap, RENESAS24X_REG_DSMFRAC_15_8,
+ (chip->divs.dsmfrac >> 8) & 0xFF);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_DSMFRAC_15_8: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting RENESAS24X_REG_DSMFRAC_7_0 (val %u @ 0x%x)",
+ chip->divs.dsmfrac & 0xFF,
+ RENESAS24X_REG_DSMFRAC_7_0);
+
+ err = __i2c_write(client, chip->regmap, RENESAS24X_REG_DSMFRAC_7_0,
+ chip->divs.dsmfrac & 0xFF);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_DSMFRAC_7_0: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting RENESAS24X_REG_NS1_Q0 (val %u @ 0x%x)",
+ chip->divs.ns1_q0, RENESAS24X_REG_NS1_Q0);
+
+ err = __i2c_write_with_mask(client, chip->regmap, RENESAS24X_REG_NS1_Q0,
+ chip->divs.ns1_q0 & RENESAS24X_REG_NS1_Q0_MASK,
+ chip->reg_ns1_q0, RENESAS24X_REG_NS1_Q0_MASK);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_NS1_Q0: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting RENESAS24X_REG_NS2_Q0_15_8 (val %u @ 0x%x)",
+ (chip->divs.ns2_q0 >> 8) & 0xFF, RENESAS24X_REG_NS2_Q0_15_8);
+
+ err = __i2c_write(client, chip->regmap, RENESAS24X_REG_NS2_Q0_15_8,
+ (chip->divs.ns2_q0 >> 8) & 0xFF);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_NS2_Q0_15_8: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting RENESAS24X_REG_NS2_Q0_7_0 (val %u @ 0x%x)",
+ chip->divs.ns2_q0 & 0xFF, RENESAS24X_REG_NS2_Q0_7_0);
+
+ err = __i2c_write(client, chip->regmap, RENESAS24X_REG_NS2_Q0_7_0,
+ chip->divs.ns2_q0 & 0xFF);
+ if (err) {
+ dev_err(&client->dev, "error setting RENESAS24X_REG_NS2_Q0_7_0: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "calling renesas24x_enable_output for Q0. requestedFreq: %u",
+ chip->clk[0].requested);
+ renesas24x_enable_output(chip, 0, chip->clk[0].requested != 0);
+
+ dev_dbg(&client->dev, "writing values for q1-q3");
+ for (x = 1; x < NUM_OUTPUTS; x++) {
+ struct clk_register_offsets offsets;
+
+ if (chip->clk[x].requested != 0) {
+ dev_dbg(&client->dev, "calling renesas24x_get_offsets for %u", x);
+ err = renesas24x_get_offsets(x, &offsets);
+ if (err) {
+ dev_err(&client->dev, "error calling renesas24x_get_offsets: %i",
+ err);
+ return err;
+ }
+
+ dev_dbg(&client->dev, "(q%u, nint: %u, nfrac: %u)",
+ x, chip->divs.nint[x - 1],
+ chip->divs.nfrac[x - 1]);
+
+ dev_dbg(&client->dev,
+ "setting n_17_16_offset (q%u, val %u @ 0x%x)",
+ x, chip->divs.nint[x - 1] >> 16,
+ offsets.n_17_16_offset);
+
+ err = __i2c_write_with_mask(client, chip->regmap,
+ offsets.n_17_16_offset,
+ (chip->divs.nint[x - 1] >> 16) &
+ offsets.n_17_16_mask,
+ chip->reg_n_qx_17_16[x - 1],
+ offsets.n_17_16_mask);
+ if (err) {
+ dev_err(&client->dev, "error setting n_17_16_offset: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting n_15_8_offset (q%u, val %u @ 0x%x)",
+ x, (chip->divs.nint[x - 1] >> 8) & 0xFF,
+ offsets.n_15_8_offset);
+
+ err = __i2c_write(client, chip->regmap,
+ offsets.n_15_8_offset,
+ (chip->divs.nint[x - 1] >> 8) & 0xFF);
+ if (err) {
+ dev_err(&client->dev, "error setting n_15_8_offset: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting n_7_0_offset (q%u, val %u @ 0x%x)",
+ x, chip->divs.nint[x - 1] & 0xFF,
+ offsets.n_7_0_offset);
+
+ err = __i2c_write(client, chip->regmap,
+ offsets.n_7_0_offset,
+ chip->divs.nint[x - 1] & 0xFF);
+ if (err) {
+ dev_err(&client->dev, "error setting n_7_0_offset: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting nfrac_27_24_offset (q%u, val %u @ 0x%x)",
+ x, (chip->divs.nfrac[x - 1] >> 24),
+ offsets.nfrac_27_24_offset);
+
+ err = __i2c_write_with_mask(client, chip->regmap,
+ offsets.nfrac_27_24_offset,
+ (chip->divs.nfrac[x - 1] >> 24) &
+ offsets.nfrac_27_24_mask,
+ chip->reg_nfrac_qx_27_24[x - 1],
+ offsets.nfrac_27_24_mask);
+ if (err) {
+ dev_err(&client->dev, "error setting nfrac_27_24_offset: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting nfrac_23_16_offset (q%u, val %u @ 0x%x)",
+ x, (chip->divs.nfrac[x - 1] >> 16) & 0xFF,
+ offsets.nfrac_23_16_offset);
+
+ err = __i2c_write(client, chip->regmap,
+ offsets.nfrac_23_16_offset,
+ (chip->divs.nfrac[x - 1] >> 16) & 0xFF);
+ if (err) {
+ dev_err(&client->dev, "error setting nfrac_23_16_offset: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting nfrac_15_8_offset (q%u, val %u @ 0x%x)",
+ x, (chip->divs.nfrac[x - 1] >> 8) & 0xFF,
+ offsets.nfrac_15_8_offset);
+
+ err = __i2c_write(client, chip->regmap, offsets.nfrac_15_8_offset,
+ (chip->divs.nfrac[x - 1] >> 8) & 0xFF);
+ if (err) {
+ dev_err(&client->dev, "error setting nfrac_15_8_offset: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev,
+ "setting nfrac_7_0_offset (q%u, val %u @ 0x%x)",
+ x, chip->divs.nfrac[x - 1] & 0xFF,
+ offsets.nfrac_7_0_offset);
+
+ err = __i2c_write(client, chip->regmap,
+ offsets.nfrac_7_0_offset,
+ chip->divs.nfrac[x - 1] & 0xFF);
+ if (err) {
+ dev_err(&client->dev, "error setting nfrac_7_0_offset: %i", err);
+ return err;
+ }
+ }
+ renesas24x_enable_output(chip, x, chip->clk[x].requested != 0);
+ chip->clk[x].actual = chip->clk[x].requested;
+ }
+ return 0;
+}
+
+/**
+ * renesas24x_set_frequency - Adjust output frequency on the attached chip.
+ * @chip: Device data structure, including all requested frequencies.
+ *
+ * Return: 0 on success.
+ */
+int renesas24x_set_frequency(struct clk_renesas24x_chip *chip)
+{
+ int err = 0, x = 0;
+ bool all_disabled = true;
+ struct i2c_client *client = chip->i2c_client;
+
+ for (x = 0; x < NUM_OUTPUTS; x++) {
+ if (chip->clk[x].requested == 0) {
+ renesas24x_enable_output(chip, x, false);
+ chip->clk[x].actual = 0;
+ } else {
+ all_disabled = false;
+ }
+ }
+
+ if (all_disabled)
+ /*
+ * no requested frequencies, so nothing else to calculate
+ * or write to the chip. If the consumer wants to disable
+ * all outputs, they can request 0 for all frequencies.
+ */
+ return 0;
+
+ if (chip->input_clk_freq == 0) {
+ dev_err(&client->dev, "no input frequency; can't continue.");
+ return -EINVAL;
+ }
+
+ err = renesas24x_calc_divs(chip);
+ if (err) {
+ dev_err(&client->dev,
+ "error calling renesas24x_calc_divs: %i", err);
+ return err;
+ }
+
+ err = renesas24x_update_device(chip);
+ if (err) {
+ dev_err(&client->dev, "error updating the device: %i", err);
+ return err;
+ }
+
+ return 0;
+}@@ -0,0 +1,573 @@
+// SPDX-License-Identifier: GPL-2.0
+/* 8t49n24x.c - Program 8T49N24x settings via I2C.
+ *
+ * Copyright (C) 2018, Renesas Electronics America <david.cater.jc@renesas.com>
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "8t49n24x-core.h"
+
+#define OUTPUTMODE_HIGHZ 0
+#define OUTPUTMODE_LVDS 2
+#define RENESAS24X_MIN_FREQ 1000000L
+#define RENESAS24X_MAX_FREQ 300000000L
+
+enum clk_renesas24x_variant { renesas24x };
+
+static u32 __mask_and_shift(u32 value, u8 mask)
+{
+ value &= mask;
+ return value >> __renesas_bits_to_shift(mask);
+}
+
+/**
+ * renesas24x_set_output_mode - Set the mode for a particular clock
+ * output in the register.
+ * @reg: The current register value before setting the mode.
+ * @mask: The bitmask identifying where in the register the
+ * output mode is stored.
+ * @mode: The mode to set.
+ *
+ * Return: the new register value with the specified mode bits set.
+ */
+static int renesas24x_set_output_mode(u32 reg, u8 mask, u8 mode)
+{
+ if (((reg & mask) >> __renesas_bits_to_shift(mask)) == OUTPUTMODE_HIGHZ) {
+ reg = reg & ~mask;
+ reg |= OUTPUTMODE_LVDS << __renesas_bits_to_shift(mask);
+ }
+ return reg;
+}
+
+/**
+ * renesas24x_read_from_hw - Get the current values on the hw
+ * @chip: Device data structure
+ *
+ * Return: 0 on success, negative errno otherwise.
+ */
+static int renesas24x_read_from_hw(struct clk_renesas24x_chip *chip)
+{
+ int err = 0;
+ u32 tmp = 0, tmp2 = 0;
+ u8 output = 0;
+ struct i2c_client *client = chip->i2c_client;
+
+ err = regmap_read(chip->regmap, RENESAS24X_REG_DSM_INT_8, &chip->reg_dsm_int_8);
+ if (err) {
+ dev_err(&client->dev, "error reading RENESAS24X_REG_DSM_INT_8: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev, "reg_dsm_int_8: 0x%x", chip->reg_dsm_int_8);
+
+ err = regmap_read(chip->regmap, RENESAS24X_REG_DSMFRAC_20_16_MASK,
+ &chip->reg_dsm_frac_20_16);
+ if (err) {
+ dev_err(&client->dev, "error reading RENESAS24X_REG_DSMFRAC_20_16_MASK: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev, "reg_dsm_frac_20_16: 0x%x", chip->reg_dsm_frac_20_16);
+
+ err = regmap_read(chip->regmap, RENESAS24X_REG_OUTEN, &chip->reg_out_en_x);
+ if (err) {
+ dev_err(&client->dev, "error reading RENESAS24X_REG_OUTEN: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev, "reg_out_en_x: 0x%x", chip->reg_out_en_x);
+
+ err = regmap_read(chip->regmap, RENESAS24X_REG_OUTMODE0_1, &tmp);
+ if (err) {
+ dev_err(&client->dev, "error reading RENESAS24X_REG_OUTMODE0_1: %i", err);
+ return err;
+ }
+
+ tmp2 = renesas24x_set_output_mode(tmp, RENESAS24X_REG_OUTMODE0_MASK, OUTPUTMODE_LVDS);
+ tmp2 = renesas24x_set_output_mode(tmp2, RENESAS24X_REG_OUTMODE1_MASK, OUTPUTMODE_LVDS);
+ dev_dbg(&client->dev,
+ "reg_out_mode_0_1 original: 0x%x. After OUT0/1 to LVDS if necessary: 0x%x",
+ tmp, tmp2);
+
+ chip->reg_out_mode_0_1 = tmp2;
+ err = regmap_read(chip->regmap, RENESAS24X_REG_OUTMODE2_3, &tmp);
+ if (err) {
+ dev_err(&client->dev, "error reading RENESAS24X_REG_OUTMODE2_3: %i", err);
+ return err;
+ }
+
+ tmp2 = renesas24x_set_output_mode(tmp, RENESAS24X_REG_OUTMODE2_MASK, OUTPUTMODE_LVDS);
+ tmp2 = renesas24x_set_output_mode(tmp2, RENESAS24X_REG_OUTMODE3_MASK, OUTPUTMODE_LVDS);
+ dev_dbg(&client->dev,
+ "reg_out_mode_2_3 original: 0x%x. After OUT2/3 to LVDS if necessary: 0x%x",
+ tmp, tmp2);
+
+ chip->reg_out_mode_2_3 = tmp2;
+ err = regmap_read(chip->regmap, RENESAS24X_REG_Q_DIS, &chip->reg_qx_dis);
+ if (err) {
+ dev_err(&client->dev, "error reading RENESAS24X_REG_Q_DIS: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev, "reg_qx_dis: 0x%x", chip->reg_qx_dis);
+
+ err = regmap_read(chip->regmap, RENESAS24X_REG_NS1_Q0, &chip->reg_ns1_q0);
+ if (err) {
+ dev_err(&client->dev, "error reading RENESAS24X_REG_NS1_Q0: %i", err);
+ return err;
+ }
+
+ dev_dbg(&client->dev, "reg_ns1_q0: 0x%x", chip->reg_ns1_q0);
+
+ for (output = 1; output <= 3; output++) {
+ struct clk_register_offsets offsets;
+
+ err = renesas24x_get_offsets(output, &offsets);
+ if (err) {
+ dev_err(&client->dev, "error calling renesas24x_get_offsets: %i", err);
+ return err;
+ }
+
+ err = regmap_read(chip->regmap, offsets.n_17_16_offset,
+ &chip->reg_n_qx_17_16[output - 1]);
+ if (err) {
+ dev_err(&client->dev,
+ "error reading n_17_16_offset output %d (offset: 0x%x): %i",
+ output, offsets.n_17_16_offset, err);
+ return err;
+ }
+
+ dev_dbg(&client->dev, "reg_n_qx_17_16[Q%u]: 0x%x", output,
+ chip->reg_n_qx_17_16[output - 1]);
+
+ err = regmap_read(chip->regmap, offsets.nfrac_27_24_offset,
+ &chip->reg_nfrac_qx_27_24[output - 1]);
+ if (err) {
+ dev_err(&client->dev,
+ "error reading nfrac_27_24_offset output %d (offset: 0x%x): %i",
+ output, offsets.nfrac_27_24_offset,
+ err);
+ return err;
+ }
+
+ dev_dbg(&client->dev, "reg_nfrac_qx_27_24[Q%u]: 0x%x", output,
+ chip->reg_nfrac_qx_27_24[output - 1]);
+ }
+
+ dev_info(&client->dev, "initial values read from chip successfully");
+
+ /* Also read DBL_DIS to determine whether the doubler is disabled. */
+ err = regmap_read(chip->regmap, RENESAS24X_REG_DBL_DIS, &tmp);
+ if (err) {
+ dev_err(&client->dev, "error reading RENESAS24X_REG_DBL_DIS: %i", err);
+ return err;
+ }
+
+ chip->doubler_disabled = __mask_and_shift(tmp, RENESAS24X_REG_DBL_DIS_MASK);
+ dev_dbg(&client->dev, "doubler_disabled: %d", chip->doubler_disabled);
+
+ return 0;
+}
+
+/**
+ * renesas24x_set_rate - Sets the specified output clock to the specified rate.
+ * @hw: clk_hw struct that identifies the specific output clock.
+ * @rate: the rate (in Hz) for the specified clock.
+ * @parent_rate:(not sure) the rate for a parent signal (e.g.,
+ * the VCO feeding the output)
+ *
+ * This function will call renesas24x_set_frequency, which means it will
+ * calculate divider for all requested outputs and update the attached
+ * device (issue I2C commands to update the registers).
+ *
+ * Return: 0 on success.
+ */
+static int renesas24x_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ int err = 0;
+
+ /*
+ * hw->clk is the pointer to the specific output clock the user is
+ * requesting. We use hw to get back to the output structure for
+ * the output clock. Set the requested rate in the output structure.
+ * Note that container_of cannot be used to find the device structure
+ * (clk_renesas24x_chip) from clk_hw, because clk_renesas24x_chip has an array
+ * of renesas24x_output structs. That is why it is necessary to use
+ * output->chip to access the device structure.
+ */
+ struct renesas24x_output *output = to_renesas24x_output(hw);
+ struct i2c_client *client = output->chip->i2c_client;
+
+ if (rate < output->chip->min_freq || rate > output->chip->max_freq) {
+ dev_err(&client->dev,
+ "requested frequency (%luHz) is out of range\n", rate);
+ return -EINVAL;
+ }
+
+ /*
+ * Set the requested frequency in the output data structure, and then
+ * call renesas24x_set_frequency. renesas24x_set_frequency considers all
+ * requested frequencies when deciding on a vco frequency and
+ * calculating dividers.
+ */
+ output->requested = rate;
+
+ dev_info(&client->dev, "calling renesas24x_set_frequency for Q%u. rate: %lu",
+ output->index, rate);
+ err = renesas24x_set_frequency(output->chip);
+ if (err)
+ dev_err(&client->dev, "error calling set_frequency: %d", err);
+
+ return err;
+}
+
+/**
+ * renesas24x_round_rate - get valid rate that is closest to the requested rate
+ * @hw: clk_hw struct that identifies the specific output clock.
+ * @rate: the rate (in Hz) for the specified clock.
+ * @parent_rate:(not sure) the rate for a parent signal (e.g., the VCO
+ * feeding the output). This is an i/o param.
+ * If the driver supports a parent clock for the output (e.g.,
+ * the VCO(?), then set this param to indicate what the rate of
+ * the parent would be (e.g., the VCO frequency) if the rounded
+ * rate is used.
+ *
+ * Returns the closest rate to the requested rate actually supported by the
+ * chip.
+ *
+ * Return: adjusted rate
+ */
+static long renesas24x_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ /*
+ * The chip has fractional output dividers, so assume it
+ * can provide the requested rate.
+ *
+ * TODO: figure out the closest rate that chip can support
+ * within a low error threshold and return that rate.
+ */
+ return rate;
+}
+
+/**
+ * renesas24x_recalc_rate - return the frequency being provided by the clock.
+ * @hw: clk_hw struct that identifies the specific output clock.
+ * @parent_rate: (not sure) the rate for a parent signal (e.g., the
+ * VCO feeding the output)
+ *
+ * This API appears to be used to read the current values from the hardware
+ * and report the frequency being provided by the clock. Without this function,
+ * the clock will be initialized to 0 by default. The OS appears to be
+ * calling this to find out what the current value of the clock is at
+ * startup, so it can determine when .set_rate is actually changing the
+ * frequency.
+ *
+ * Return: the frequency of the specified clock.
+ */
+static unsigned long renesas24x_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct renesas24x_output *output = to_renesas24x_output(hw);
+
+ return output->requested;
+}
+
+/*
+ * Note that .prepare and .unprepare appear to be used more in Gates.
+ * They do not appear to be necessary for this device.
+ * Instead, update the device when .set_rate is called.
+ */
+static const struct clk_ops renesas24x_clk_ops = {
+ .recalc_rate = renesas24x_recalc_rate,
+ .round_rate = renesas24x_round_rate,
+ .set_rate = renesas24x_set_rate,
+};
+
+static bool renesas24x_regmap_is_volatile(struct device *dev, unsigned int reg)
+{
+ return false;
+}
+
+static bool renesas24x_regmap_is_writeable(struct device *dev, unsigned int reg)
+{
+ return true;
+}
+
+static const struct regmap_config renesas24x_regmap_config = {
+ .reg_bits = 16,
+ .val_bits = 8,
+ .cache_type = REGCACHE_RBTREE,
+ .max_register = 0xffff,
+ .writeable_reg = renesas24x_regmap_is_writeable,
+ .volatile_reg = renesas24x_regmap_is_volatile,
+};
+
+/**
+ * renesas24x_clk_notifier_cb - Clock rate change callback
+ * @nb: Pointer to notifier block
+ * @event: Notification reason
+ * @data: Pointer to notification data object
+ *
+ * This function is called when the input clock frequency changes.
+ * The callback checks whether a valid bus frequency can be generated after the
+ * change. If so, the change is acknowledged, otherwise the change is aborted.
+ * New dividers are written to the HW in the pre- or post change notification
+ * depending on the scaling direction.
+ *
+ * Return: NOTIFY_STOP if the rate change should be aborted, NOTIFY_OK
+ * to acknowledge the change, NOTIFY_DONE if the notification is
+ * considered irrelevant.
+ */
+static int renesas24x_clk_notifier_cb(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct clk_notifier_data *ndata = data;
+ struct clk_renesas24x_chip *chip = to_clk_renesas24x_from_nb(nb);
+ int err = 0;
+
+ dev_info(&chip->i2c_client->dev, "input changed: %lu Hz. event: %lu",
+ ndata->new_rate, event);
+
+ switch (event) {
+ case PRE_RATE_CHANGE: {
+ dev_dbg(&chip->i2c_client->dev, "PRE_RATE_CHANGE\n");
+ return NOTIFY_OK;
+ }
+ case POST_RATE_CHANGE:
+ chip->input_clk_freq = ndata->new_rate;
+ /*
+ * Can't call clock API clk_set_rate here; I believe
+ * it will be ignored if the rate is the same as we
+ * set previously. Need to call our internal function.
+ */
+ dev_dbg(&chip->i2c_client->dev, "POST_RATE_CHANGE. Calling renesas24x_set_frequency\n");
+ err = renesas24x_set_frequency(chip);
+ if (err)
+ dev_err(&chip->i2c_client->dev, "error setting frequency (%i)\n", err);
+ return NOTIFY_OK;
+ case ABORT_RATE_CHANGE:
+ return NOTIFY_OK;
+ default:
+ return NOTIFY_DONE;
+ }
+}
+
+static struct clk_hw *of_clk_renesas24x_get(struct of_phandle_args *clkspec,
+ void *_data)
+{
+ struct clk_renesas24x_chip *chip = _data;
+ unsigned int idx = clkspec->args[0];
+
+ if (idx >= ARRAY_SIZE(chip->clk)) {
+ pr_err("invalid index %u\n", idx);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return &chip->clk[idx].hw;
+}
+
+/**
+ * renesas24x_probe - main entry point for ccf driver
+ * @client: pointer to i2c_client structure
+ * @id: pointer to i2c_device_id structure
+ *
+ * Main entry point function that gets called to initialize the driver.
+ *
+ * Return: 0 for success.
+ */
+static int renesas24x_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct clk_renesas24x_chip *chip;
+ struct clk_init_data init;
+
+ int err = 0, x = 0;
+ char buf[6];
+
+ chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ init.ops = &renesas24x_clk_ops;
+ init.flags = 0;
+ init.num_parents = 0;
+ chip->i2c_client = client;
+
+ chip->min_freq = RENESAS24X_MIN_FREQ;
+ chip->max_freq = RENESAS24X_MAX_FREQ;
+
+ for (x = 0; x < NUM_INPUTS + 1; x++) {
+ char name[12];
+
+ sprintf(name, x == NUM_INPUTS ? "input-xtal" : "input-clk%i", x);
+ dev_dbg(&client->dev, "attempting to get %s", name);
+ chip->input_clk = devm_clk_get(&client->dev, name);
+ if (IS_ERR(chip->input_clk)) {
+ err = PTR_ERR(chip->input_clk);
+ /*
+ * TODO: Handle EPROBE_DEFER error, which indicates
+ * that the input_clk isn't available now but may be
+ * later when the appropriate module is loaded.
+ */
+ } else {
+ err = 0;
+ chip->input_clk_num = x;
+ break;
+ }
+ }
+
+ if (err) {
+ dev_err(&client->dev, "Unable to get input clock, error %d", err);
+ chip->input_clk = NULL;
+ return err;
+ }
+
+ chip->input_clk_freq = clk_get_rate(chip->input_clk);
+ dev_dbg(&client->dev, "Got input-freq from input-clk in device tree: %uHz",
+ chip->input_clk_freq);
+
+ chip->input_clk_nb.notifier_call = renesas24x_clk_notifier_cb;
+ if (clk_notifier_register(chip->input_clk, &chip->input_clk_nb))
+ dev_warn(&client->dev, "Unable to register clock notifier for input_clk.");
+
+ dev_dbg(&client->dev, "about to read settings: %zu", ARRAY_SIZE(chip->settings));
+
+ err = of_property_read_u8_array(client->dev.of_node, "settings", chip->settings,
+ ARRAY_SIZE(chip->settings));
+ if (!err) {
+ dev_dbg(&client->dev, "settings property specified in DT");
+ chip->has_settings = true;
+ } else {
+ if (err == -EOVERFLOW) {
+ dev_alert(&client->dev, "EOVERFLOW reading settings. ARRAY_SIZE: %zu",
+ ARRAY_SIZE(chip->settings));
+ return err;
+ }
+ dev_dbg(&client->dev,
+ "settings property missing in DT (or an error that can be ignored: %i).",
+ err);
+ }
+
+ /*
+ * Requested output frequencies cannot be specified in the DT.
+ * Either a consumer needs to use the clock API to request the rate.
+ * Use clock-names in DT to specify the output clock.
+ */
+
+ chip->regmap = devm_regmap_init_i2c(client, &renesas24x_regmap_config);
+ if (IS_ERR(chip->regmap)) {
+ dev_err(&client->dev, "failed to allocate register map\n");
+ return PTR_ERR(chip->regmap);
+ }
+
+ dev_dbg(&client->dev, "call i2c_set_clientdata");
+ i2c_set_clientdata(client, chip);
+
+ if (chip->has_settings) {
+ /*
+ * A raw settings array was specified in the DT. Write the
+ * settings to the device immediately.
+ */
+ err = __renesas_i2c_write_bulk(chip->i2c_client, chip->regmap, 0, chip->settings,
+ ARRAY_SIZE(chip->settings));
+ if (err) {
+ dev_err(&client->dev, "error writing all settings to chip (%i)\n", err);
+ return err;
+ }
+ dev_dbg(&client->dev, "successfully wrote full settings array");
+ }
+
+ /*
+ * Whether or not settings were written to the device, read all
+ * current values from the hw.
+ */
+ dev_dbg(&client->dev, "read from HW");
+ err = renesas24x_read_from_hw(chip);
+ if (err) {
+ dev_err(&client->dev, "failed calling renesas24x_read_from_hw (%i)\n", err);
+ return err;
+ }
+
+ /* Create all 4 clocks */
+ for (x = 0; x < NUM_OUTPUTS; x++) {
+ init.name = kasprintf(GFP_KERNEL, "%s.Q%i", client->dev.of_node->name, x);
+ chip->clk[x].chip = chip;
+ chip->clk[x].hw.init = &init;
+ chip->clk[x].index = x;
+ err = devm_clk_hw_register(&client->dev, &chip->clk[x].hw);
+ kfree(init.name); /* clock framework made a copy of the name */
+ if (err) {
+ dev_err(&client->dev, "clock registration failed\n");
+ return err;
+ }
+ dev_dbg(&client->dev, "successfully registered Q%i", x);
+ }
+
+ if (err) {
+ dev_err(&client->dev, "clock registration failed\n");
+ return err;
+ }
+
+ err = of_clk_add_hw_provider(client->dev.of_node, of_clk_renesas24x_get, chip);
+ if (err) {
+ dev_err(&client->dev, "unable to add clk provider\n");
+ return err;
+ }
+
+ if (chip->input_clk_num == NUM_INPUTS)
+ sprintf(buf, "XTAL");
+ else
+ sprintf(buf, "CLK%i", chip->input_clk_num);
+
+ dev_info(&client->dev,
+ "probe success. input freq: %uHz (%s), settings string? %s\n",
+ chip->input_clk_freq, buf,
+ chip->has_settings ? "true" : "false");
+
+ return 0;
+}
+
+static int renesas24x_remove(struct i2c_client *client)
+{
+ struct clk_renesas24x_chip *chip = to_clk_renesas24x_from_client(&client);
+
+ of_clk_del_provider(client->dev.of_node);
+
+ if (!chip->input_clk)
+ clk_notifier_unregister(chip->input_clk, &chip->input_clk_nb);
+ return 0;
+}
+
+static const struct i2c_device_id renesas24x_id[] = {
+ { "8t49n24x", renesas24x },
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, renesas24x_id);
+
+static const struct of_device_id renesas24x_of_match[] = {
+ { .compatible = "renesas,8t49n241" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, renesas24x_of_match);
+
+static struct i2c_driver renesas24x_driver = {
+ .driver = {
+ .name = "8t49n24x",
+ .of_match_table = renesas24x_of_match,
+ },
+ .probe = renesas24x_probe,
+ .remove = renesas24x_remove,
+ .id_table = renesas24x_id,
+};
+
+module_i2c_driver(renesas24x_driver);
+
+MODULE_DESCRIPTION("8T49N24x ccf driver");
+MODULE_AUTHOR("David Cater <david.cater.jc@renesas.com>");
+MODULE_AUTHOR("Alex Helms <alexander.helms.jy@renesas.com>");
+MODULE_LICENSE("GPL v2");