1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * drivers/media/i2c/ccs/ccs-reg-access.c 4 * 5 * Generic driver for MIPI CCS/SMIA/SMIA++ compliant camera sensors 6 * 7 * Copyright (C) 2020 Intel Corporation 8 * Copyright (C) 2011--2012 Nokia Corporation 9 * 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 20 static 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 to 47 * 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 else 57 man <<= exp; 58 59 man >>= 23; /* Remove mantissa bias */ 60 61 return man & 0xffffffff; 62 } 63 64 65 static 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 76 u32 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 else 85 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 */ 97 static 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 } 111 112 static 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 } 149 150 static int 151 ccs_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 } 162 163 static 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 } 191 192 int 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 } 196 197 int 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 } 201 202 int 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 */ 211 int 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 32U 232 233 int 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