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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * drivers/media/i2c/ccs/ccs-reg-access.c4 *5 * Generic driver for MIPI CCS/SMIA/SMIA++ compliant camera sensors6 *7 * Copyright (C) 2020 Intel Corporation8 * Copyright (C) 2011--2012 Nokia Corporation9 * Contact: Sakari Ailus <sakari.ailus@linux.intel.com>10 */11 12#include <linux/unaligned.h>13 14#include <linux/delay.h>15#include <linux/i2c.h>16 17#include "ccs.h"18#include "ccs-limits.h"19 20static u32 float_to_u32_mul_1000000(struct i2c_client *client, u32 phloat)21{22 s32 exp;23 u64 man;24 25 if (phloat >= 0x80000000) {26 dev_err(&client->dev, "this is a negative number\n");27 return 0;28 }29 30 if (phloat == 0x7f800000)31 return ~0; /* Inf. */32 33 if ((phloat & 0x7f800000) == 0x7f800000) {34 dev_err(&client->dev, "NaN or other special number\n");35 return 0;36 }37 38 /* Valid cases begin here */39 if (phloat == 0)40 return 0; /* Valid zero */41 42 if (phloat > 0x4f800000)43 return ~0; /* larger than 4294967295 */44 45 /*46 * Unbias exponent (note how phloat is now guaranteed to47 * have 0 in the high bit)48 */49 exp = ((int32_t)phloat >> 23) - 127;50 51 /* Extract mantissa, add missing '1' bit and it's in MHz */52 man = ((phloat & 0x7fffff) | 0x800000) * 1000000ULL;53 54 if (exp < 0)55 man >>= -exp;56 else57 man <<= exp;58 59 man >>= 23; /* Remove mantissa bias */60 61 return man & 0xffffffff;62}63 64 65static u32 ireal32_to_u32_mul_1000000(struct i2c_client *client, u32 val)66{67 if (val >> 10 > U32_MAX / 15625) {68 dev_warn(&client->dev, "value %u overflows!\n", val);69 return U32_MAX;70 }71 72 return ((val >> 10) * 15625) +73 (val & GENMASK(9, 0)) * 15625 / 1024;74}75 76u32 ccs_reg_conv(struct ccs_sensor *sensor, u32 reg, u32 val)77{78 struct i2c_client *client = v4l2_get_subdevdata(&sensor->src->sd);79 80 if (reg & CCS_FL_FLOAT_IREAL) {81 if (CCS_LIM(sensor, CLOCK_CAPA_TYPE_CAPABILITY) &82 CCS_CLOCK_CAPA_TYPE_CAPABILITY_IREAL)83 val = ireal32_to_u32_mul_1000000(client, val);84 else85 val = float_to_u32_mul_1000000(client, val);86 } else if (reg & CCS_FL_IREAL) {87 val = ireal32_to_u32_mul_1000000(client, val);88 }89 90 return val;91}92 93/*94 * Read a 8/16/32-bit i2c register. The value is returned in 'val'.95 * Returns zero if successful, or non-zero otherwise.96 */97static int __ccs_read_addr(struct ccs_sensor *sensor, u32 reg, u32 *val,98 bool only8, bool conv)99{100 u64 __val;101 int rval;102 103 rval = cci_read(sensor->regmap, reg, &__val, NULL);104 if (rval < 0)105 return rval;106 107 *val = conv ? ccs_reg_conv(sensor, reg, __val) : __val;108 109 return 0;110}111 112static int __ccs_static_data_read_ro_reg(struct ccs_reg *regs, size_t num_regs,113 u32 reg, u32 *val)114{115 unsigned int width = CCI_REG_WIDTH_BYTES(reg);116 size_t i;117 118 for (i = 0; i < num_regs; i++, regs++) {119 u8 *data;120 121 if (regs->addr + regs->len < CCS_REG_ADDR(reg) + width)122 continue;123 124 if (regs->addr > CCS_REG_ADDR(reg))125 break;126 127 data = ®s->value[CCS_REG_ADDR(reg) - regs->addr];128 129 switch (width) {130 case sizeof(u8):131 *val = *data;132 break;133 case sizeof(u16):134 *val = get_unaligned_be16(data);135 break;136 case sizeof(u32):137 *val = get_unaligned_be32(data);138 break;139 default:140 WARN_ON(1);141 return -EINVAL;142 }143 144 return 0;145 }146 147 return -ENOENT;148}149 150static int151ccs_static_data_read_ro_reg(struct ccs_sensor *sensor, u32 reg, u32 *val)152{153 if (!__ccs_static_data_read_ro_reg(sensor->sdata.sensor_read_only_regs,154 sensor->sdata.num_sensor_read_only_regs,155 reg, val))156 return 0;157 158 return __ccs_static_data_read_ro_reg(sensor->mdata.module_read_only_regs,159 sensor->mdata.num_module_read_only_regs,160 reg, val);161}162 163static int ccs_read_addr_raw(struct ccs_sensor *sensor, u32 reg, u32 *val,164 bool force8, bool quirk, bool conv, bool data)165{166 int rval;167 168 if (data) {169 rval = ccs_static_data_read_ro_reg(sensor, reg, val);170 if (!rval)171 return 0;172 }173 174 if (quirk) {175 *val = 0;176 rval = ccs_call_quirk(sensor, reg_access, false, ®, val);177 if (rval == -ENOIOCTLCMD)178 return 0;179 if (rval < 0)180 return rval;181 182 if (force8)183 return __ccs_read_addr(sensor, reg, val, true, conv);184 }185 186 return __ccs_read_addr(sensor, reg, val,187 ccs_needs_quirk(sensor,188 CCS_QUIRK_FLAG_8BIT_READ_ONLY),189 conv);190}191 192int ccs_read_addr(struct ccs_sensor *sensor, u32 reg, u32 *val)193{194 return ccs_read_addr_raw(sensor, reg, val, false, true, true, true);195}196 197int ccs_read_addr_8only(struct ccs_sensor *sensor, u32 reg, u32 *val)198{199 return ccs_read_addr_raw(sensor, reg, val, true, true, true, true);200}201 202int ccs_read_addr_noconv(struct ccs_sensor *sensor, u32 reg, u32 *val)203{204 return ccs_read_addr_raw(sensor, reg, val, false, true, false, true);205}206 207/*208 * Write to a 8/16-bit register.209 * Returns zero if successful, or non-zero otherwise.210 */211int ccs_write_addr(struct ccs_sensor *sensor, u32 reg, u32 val)212{213 unsigned int retries = 10;214 int rval;215 216 rval = ccs_call_quirk(sensor, reg_access, true, ®, &val);217 if (rval == -ENOIOCTLCMD)218 return 0;219 if (rval < 0)220 return rval;221 222 rval = 0;223 do {224 if (cci_write(sensor->regmap, reg, val, &rval))225 fsleep(1000);226 } while (rval && --retries);227 228 return rval;229}230 231#define MAX_WRITE_LEN 32U232 233int ccs_write_data_regs(struct ccs_sensor *sensor, struct ccs_reg *regs,234 size_t num_regs)235{236 struct i2c_client *client = v4l2_get_subdevdata(&sensor->src->sd);237 size_t i;238 239 for (i = 0; i < num_regs; i++, regs++) {240 unsigned char *regdata = regs->value;241 unsigned int j;242 int len;243 244 for (j = 0; j < regs->len; j += len, regdata += len) {245 char printbuf[(MAX_WRITE_LEN << 1) +246 1 /* \0 */] = { 0 };247 unsigned int retries = 10;248 int rval;249 250 len = min(regs->len - j, MAX_WRITE_LEN);251 252 bin2hex(printbuf, regdata, len);253 dev_dbg(&client->dev,254 "writing msr reg 0x%4.4x value 0x%s\n",255 regs->addr + j, printbuf);256 257 do {258 rval = regmap_bulk_write(sensor->regmap,259 regs->addr + j,260 regdata, len);261 if (rval)262 fsleep(1000);263 } while (rval && --retries);264 265 if (rval) {266 dev_err(&client->dev,267 "error writing %u octets to address 0x%4.4x\n",268 len, regs->addr + j);269 return rval;270 }271 }272 }273 274 return 0;275}276