|  | // SPDX-License-Identifier: GPL-2.0-only | 
|  | /* | 
|  | * drivers/media/i2c/ccs/ccs-reg-access.c | 
|  | * | 
|  | * Generic driver for MIPI CCS/SMIA/SMIA++ compliant camera sensors | 
|  | * | 
|  | * Copyright (C) 2020 Intel Corporation | 
|  | * Copyright (C) 2011--2012 Nokia Corporation | 
|  | * Contact: Sakari Ailus <sakari.ailus@linux.intel.com> | 
|  | */ | 
|  |  | 
|  | #include <asm/unaligned.h> | 
|  |  | 
|  | #include <linux/delay.h> | 
|  | #include <linux/i2c.h> | 
|  |  | 
|  | #include "ccs.h" | 
|  | #include "ccs-limits.h" | 
|  |  | 
|  | static u32 float_to_u32_mul_1000000(struct i2c_client *client, u32 phloat) | 
|  | { | 
|  | s32 exp; | 
|  | u64 man; | 
|  |  | 
|  | if (phloat >= 0x80000000) { | 
|  | dev_err(&client->dev, "this is a negative number\n"); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (phloat == 0x7f800000) | 
|  | return ~0; /* Inf. */ | 
|  |  | 
|  | if ((phloat & 0x7f800000) == 0x7f800000) { | 
|  | dev_err(&client->dev, "NaN or other special number\n"); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Valid cases begin here */ | 
|  | if (phloat == 0) | 
|  | return 0; /* Valid zero */ | 
|  |  | 
|  | if (phloat > 0x4f800000) | 
|  | return ~0; /* larger than 4294967295 */ | 
|  |  | 
|  | /* | 
|  | * Unbias exponent (note how phloat is now guaranteed to | 
|  | * have 0 in the high bit) | 
|  | */ | 
|  | exp = ((int32_t)phloat >> 23) - 127; | 
|  |  | 
|  | /* Extract mantissa, add missing '1' bit and it's in MHz */ | 
|  | man = ((phloat & 0x7fffff) | 0x800000) * 1000000ULL; | 
|  |  | 
|  | if (exp < 0) | 
|  | man >>= -exp; | 
|  | else | 
|  | man <<= exp; | 
|  |  | 
|  | man >>= 23; /* Remove mantissa bias */ | 
|  |  | 
|  | return man & 0xffffffff; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* | 
|  | * Read a 8/16/32-bit i2c register.  The value is returned in 'val'. | 
|  | * Returns zero if successful, or non-zero otherwise. | 
|  | */ | 
|  | static int ____ccs_read_addr(struct ccs_sensor *sensor, u16 reg, u16 len, | 
|  | u32 *val) | 
|  | { | 
|  | struct i2c_client *client = v4l2_get_subdevdata(&sensor->src->sd); | 
|  | struct i2c_msg msg; | 
|  | unsigned char data_buf[sizeof(u32)] = { 0 }; | 
|  | unsigned char offset_buf[sizeof(u16)]; | 
|  | int r; | 
|  |  | 
|  | if (len > sizeof(data_buf)) | 
|  | return -EINVAL; | 
|  |  | 
|  | msg.addr = client->addr; | 
|  | msg.flags = 0; | 
|  | msg.len = sizeof(offset_buf); | 
|  | msg.buf = offset_buf; | 
|  | put_unaligned_be16(reg, offset_buf); | 
|  |  | 
|  | r = i2c_transfer(client->adapter, &msg, 1); | 
|  | if (r != 1) { | 
|  | if (r >= 0) | 
|  | r = -EBUSY; | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | msg.len = len; | 
|  | msg.flags = I2C_M_RD; | 
|  | msg.buf = &data_buf[sizeof(data_buf) - len]; | 
|  |  | 
|  | r = i2c_transfer(client->adapter, &msg, 1); | 
|  | if (r != 1) { | 
|  | if (r >= 0) | 
|  | r = -EBUSY; | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | *val = get_unaligned_be32(data_buf); | 
|  |  | 
|  | return 0; | 
|  |  | 
|  | err: | 
|  | dev_err(&client->dev, "read from offset 0x%x error %d\n", reg, r); | 
|  |  | 
|  | return r; | 
|  | } | 
|  |  | 
|  | /* Read a register using 8-bit access only. */ | 
|  | static int ____ccs_read_addr_8only(struct ccs_sensor *sensor, u16 reg, | 
|  | u16 len, u32 *val) | 
|  | { | 
|  | unsigned int i; | 
|  | int rval; | 
|  |  | 
|  | *val = 0; | 
|  |  | 
|  | for (i = 0; i < len; i++) { | 
|  | u32 val8; | 
|  |  | 
|  | rval = ____ccs_read_addr(sensor, reg + i, 1, &val8); | 
|  | if (rval < 0) | 
|  | return rval; | 
|  | *val |= val8 << ((len - i - 1) << 3); | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | unsigned int ccs_reg_width(u32 reg) | 
|  | { | 
|  | if (reg & CCS_FL_16BIT) | 
|  | return sizeof(u16); | 
|  | if (reg & CCS_FL_32BIT) | 
|  | return sizeof(u32); | 
|  |  | 
|  | return sizeof(u8); | 
|  | } | 
|  |  | 
|  | static u32 ireal32_to_u32_mul_1000000(struct i2c_client *client, u32 val) | 
|  | { | 
|  | if (val >> 10 > U32_MAX / 15625) { | 
|  | dev_warn(&client->dev, "value %u overflows!\n", val); | 
|  | return U32_MAX; | 
|  | } | 
|  |  | 
|  | return ((val >> 10) * 15625) + | 
|  | (val & GENMASK(9, 0)) * 15625 / 1024; | 
|  | } | 
|  |  | 
|  | u32 ccs_reg_conv(struct ccs_sensor *sensor, u32 reg, u32 val) | 
|  | { | 
|  | struct i2c_client *client = v4l2_get_subdevdata(&sensor->src->sd); | 
|  |  | 
|  | if (reg & CCS_FL_FLOAT_IREAL) { | 
|  | if (CCS_LIM(sensor, CLOCK_CAPA_TYPE_CAPABILITY) & | 
|  | CCS_CLOCK_CAPA_TYPE_CAPABILITY_IREAL) | 
|  | val = ireal32_to_u32_mul_1000000(client, val); | 
|  | else | 
|  | val = float_to_u32_mul_1000000(client, val); | 
|  | } else if (reg & CCS_FL_IREAL) { | 
|  | val = ireal32_to_u32_mul_1000000(client, val); | 
|  | } | 
|  |  | 
|  | return val; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Read a 8/16/32-bit i2c register.  The value is returned in 'val'. | 
|  | * Returns zero if successful, or non-zero otherwise. | 
|  | */ | 
|  | static int __ccs_read_addr(struct ccs_sensor *sensor, u32 reg, u32 *val, | 
|  | bool only8, bool conv) | 
|  | { | 
|  | unsigned int len = ccs_reg_width(reg); | 
|  | int rval; | 
|  |  | 
|  | if (!only8) | 
|  | rval = ____ccs_read_addr(sensor, CCS_REG_ADDR(reg), len, val); | 
|  | else | 
|  | rval = ____ccs_read_addr_8only(sensor, CCS_REG_ADDR(reg), len, | 
|  | val); | 
|  | if (rval < 0) | 
|  | return rval; | 
|  |  | 
|  | if (!conv) | 
|  | return 0; | 
|  |  | 
|  | *val = ccs_reg_conv(sensor, reg, *val); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int __ccs_read_data(struct ccs_reg *regs, size_t num_regs, | 
|  | u32 reg, u32 *val) | 
|  | { | 
|  | unsigned int width = ccs_reg_width(reg); | 
|  | size_t i; | 
|  |  | 
|  | for (i = 0; i < num_regs; i++, regs++) { | 
|  | u8 *data; | 
|  |  | 
|  | if (regs->addr + regs->len < CCS_REG_ADDR(reg) + width) | 
|  | continue; | 
|  |  | 
|  | if (regs->addr > CCS_REG_ADDR(reg)) | 
|  | break; | 
|  |  | 
|  | data = ®s->value[CCS_REG_ADDR(reg) - regs->addr]; | 
|  |  | 
|  | switch (width) { | 
|  | case sizeof(u8): | 
|  | *val = *data; | 
|  | break; | 
|  | case sizeof(u16): | 
|  | *val = get_unaligned_be16(data); | 
|  | break; | 
|  | case sizeof(u32): | 
|  | *val = get_unaligned_be32(data); | 
|  | break; | 
|  | default: | 
|  | WARN_ON(1); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | return -ENOENT; | 
|  | } | 
|  |  | 
|  | static int ccs_read_data(struct ccs_sensor *sensor, u32 reg, u32 *val) | 
|  | { | 
|  | if (!__ccs_read_data(sensor->sdata.sensor_read_only_regs, | 
|  | sensor->sdata.num_sensor_read_only_regs, | 
|  | reg, val)) | 
|  | return 0; | 
|  |  | 
|  | return __ccs_read_data(sensor->mdata.module_read_only_regs, | 
|  | sensor->mdata.num_module_read_only_regs, | 
|  | reg, val); | 
|  | } | 
|  |  | 
|  | static int ccs_read_addr_raw(struct ccs_sensor *sensor, u32 reg, u32 *val, | 
|  | bool force8, bool quirk, bool conv, bool data) | 
|  | { | 
|  | int rval; | 
|  |  | 
|  | if (data) { | 
|  | rval = ccs_read_data(sensor, reg, val); | 
|  | if (!rval) | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (quirk) { | 
|  | *val = 0; | 
|  | rval = ccs_call_quirk(sensor, reg_access, false, ®, val); | 
|  | if (rval == -ENOIOCTLCMD) | 
|  | return 0; | 
|  | if (rval < 0) | 
|  | return rval; | 
|  |  | 
|  | if (force8) | 
|  | return __ccs_read_addr(sensor, reg, val, true, conv); | 
|  | } | 
|  |  | 
|  | return __ccs_read_addr(sensor, reg, val, | 
|  | ccs_needs_quirk(sensor, | 
|  | CCS_QUIRK_FLAG_8BIT_READ_ONLY), | 
|  | conv); | 
|  | } | 
|  |  | 
|  | int ccs_read_addr(struct ccs_sensor *sensor, u32 reg, u32 *val) | 
|  | { | 
|  | return ccs_read_addr_raw(sensor, reg, val, false, true, true, true); | 
|  | } | 
|  |  | 
|  | int ccs_read_addr_8only(struct ccs_sensor *sensor, u32 reg, u32 *val) | 
|  | { | 
|  | return ccs_read_addr_raw(sensor, reg, val, true, true, true, true); | 
|  | } | 
|  |  | 
|  | int ccs_read_addr_noconv(struct ccs_sensor *sensor, u32 reg, u32 *val) | 
|  | { | 
|  | return ccs_read_addr_raw(sensor, reg, val, false, true, false, true); | 
|  | } | 
|  |  | 
|  | static int ccs_write_retry(struct i2c_client *client, struct i2c_msg *msg) | 
|  | { | 
|  | unsigned int retries; | 
|  | int r; | 
|  |  | 
|  | for (retries = 0; retries < 10; retries++) { | 
|  | /* | 
|  | * Due to unknown reason sensor stops responding. This | 
|  | * loop is a temporaty solution until the root cause | 
|  | * is found. | 
|  | */ | 
|  | r = i2c_transfer(client->adapter, msg, 1); | 
|  | if (r != 1) { | 
|  | usleep_range(1000, 2000); | 
|  | continue; | 
|  | } | 
|  |  | 
|  | if (retries) | 
|  | dev_err(&client->dev, | 
|  | "sensor i2c stall encountered. retries: %d\n", | 
|  | retries); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | return r; | 
|  | } | 
|  |  | 
|  | int ccs_write_addr_no_quirk(struct ccs_sensor *sensor, u32 reg, u32 val) | 
|  | { | 
|  | struct i2c_client *client = v4l2_get_subdevdata(&sensor->src->sd); | 
|  | struct i2c_msg msg; | 
|  | unsigned char data[6]; | 
|  | unsigned int len = ccs_reg_width(reg); | 
|  | int r; | 
|  |  | 
|  | if (len > sizeof(data) - 2) | 
|  | return -EINVAL; | 
|  |  | 
|  | msg.addr = client->addr; | 
|  | msg.flags = 0; /* Write */ | 
|  | msg.len = 2 + len; | 
|  | msg.buf = data; | 
|  |  | 
|  | put_unaligned_be16(CCS_REG_ADDR(reg), data); | 
|  | put_unaligned_be32(val << (8 * (sizeof(val) - len)), data + 2); | 
|  |  | 
|  | dev_dbg(&client->dev, "writing reg 0x%4.4x value 0x%*.*x (%u)\n", | 
|  | CCS_REG_ADDR(reg), ccs_reg_width(reg) << 1, | 
|  | ccs_reg_width(reg) << 1, val, val); | 
|  |  | 
|  | r = ccs_write_retry(client, &msg); | 
|  | if (r) | 
|  | dev_err(&client->dev, | 
|  | "wrote 0x%x to offset 0x%x error %d\n", val, | 
|  | CCS_REG_ADDR(reg), r); | 
|  |  | 
|  | return r; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Write to a 8/16-bit register. | 
|  | * Returns zero if successful, or non-zero otherwise. | 
|  | */ | 
|  | int ccs_write_addr(struct ccs_sensor *sensor, u32 reg, u32 val) | 
|  | { | 
|  | int rval; | 
|  |  | 
|  | rval = ccs_call_quirk(sensor, reg_access, true, ®, &val); | 
|  | if (rval == -ENOIOCTLCMD) | 
|  | return 0; | 
|  | if (rval < 0) | 
|  | return rval; | 
|  |  | 
|  | return ccs_write_addr_no_quirk(sensor, reg, val); | 
|  | } | 
|  |  | 
|  | #define MAX_WRITE_LEN	32U | 
|  |  | 
|  | int ccs_write_data_regs(struct ccs_sensor *sensor, struct ccs_reg *regs, | 
|  | size_t num_regs) | 
|  | { | 
|  | struct i2c_client *client = v4l2_get_subdevdata(&sensor->src->sd); | 
|  | unsigned char buf[2 + MAX_WRITE_LEN]; | 
|  | struct i2c_msg msg = { | 
|  | .addr = client->addr, | 
|  | .buf = buf, | 
|  | }; | 
|  | size_t i; | 
|  |  | 
|  | for (i = 0; i < num_regs; i++, regs++) { | 
|  | unsigned char *regdata = regs->value; | 
|  | unsigned int j; | 
|  |  | 
|  | for (j = 0; j < regs->len; | 
|  | j += msg.len - 2, regdata += msg.len - 2) { | 
|  | char printbuf[(MAX_WRITE_LEN << 1) + | 
|  | 1 /* \0 */] = { 0 }; | 
|  | int rval; | 
|  |  | 
|  | msg.len = min(regs->len - j, MAX_WRITE_LEN); | 
|  |  | 
|  | bin2hex(printbuf, regdata, msg.len); | 
|  | dev_dbg(&client->dev, | 
|  | "writing msr reg 0x%4.4x value 0x%s\n", | 
|  | regs->addr + j, printbuf); | 
|  |  | 
|  | put_unaligned_be16(regs->addr + j, buf); | 
|  | memcpy(buf + 2, regdata, msg.len); | 
|  |  | 
|  | msg.len += 2; | 
|  |  | 
|  | rval = ccs_write_retry(client, &msg); | 
|  | if (rval) { | 
|  | dev_err(&client->dev, | 
|  | "error writing %u octets to address 0x%4.4x\n", | 
|  | msg.len, regs->addr + j); | 
|  | return rval; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } |