projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 65b39741 HG |
1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | /* | |
| 3 | * I2C register access helpers for Omnivision OVxxxx image sensors which expect | |
| 4 | * a 16 bit register address in big-endian format and which have 1-3 byte | |
| 5 | * wide registers, in big-endian format (for the higher width registers). | |
| 6 | * | |
| 7 | * Based on the register helpers from drivers/media/i2c/ov2680.c which is: | |
| 8 | * Copyright (C) 2018 Linaro Ltd | |
| 9 | */ | |
| 10 | #ifndef __OV_16BIT_ADDR_REG_HELPERS_H | |
| 11 | #define __OV_16BIT_ADDR_REG_HELPERS_H | |
| 12 | ||
| 13 | #include <asm/unaligned.h> | |
| 14 | #include <linux/dev_printk.h> | |
| 15 | #include <linux/i2c.h> | |
| 16 | ||
| 17 | static inline int ov_read_reg(struct i2c_client *client, u16 reg, | |
| 18 | unsigned int len, u32 *val) | |
| 19 | { | |
| 20 | u8 addr_buf[2], data_buf[4] = { }; | |
| 21 | struct i2c_msg msgs[2]; | |
| 22 | int ret; | |
| 23 | ||
| 24 | if (len > 4) | |
| 25 | return -EINVAL; | |
| 26 | ||
| 27 | put_unaligned_be16(reg, addr_buf); | |
| 28 | ||
| 29 | msgs[0].addr = client->addr; | |
| 30 | msgs[0].flags = 0; | |
| 31 | msgs[0].len = ARRAY_SIZE(addr_buf); | |
| 32 | msgs[0].buf = addr_buf; | |
| 33 | ||
| 34 | msgs[1].addr = client->addr; | |
| 35 | msgs[1].flags = I2C_M_RD; | |
| 36 | msgs[1].len = len; | |
| 37 | msgs[1].buf = &data_buf[4 - len]; | |
| 38 | ||
| 39 | ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); | |
| 40 | if (ret != ARRAY_SIZE(msgs)) { | |
| 41 | dev_err(&client->dev, "read error: reg=0x%4x: %d\n", reg, ret); | |
| 42 | return -EIO; | |
| 43 | } | |
| 44 | ||
| 45 | *val = get_unaligned_be32(data_buf); | |
| 46 | ||
| 47 | return 0; | |
| 48 | } | |
| 49 | ||
| 50 | #define ov_read_reg8(s, r, v) ov_read_reg(s, r, 1, v) | |
| 51 | #define ov_read_reg16(s, r, v) ov_read_reg(s, r, 2, v) | |
| 52 | #define ov_read_reg24(s, r, v) ov_read_reg(s, r, 3, v) | |
| 53 | ||
| 54 | static inline int ov_write_reg(struct i2c_client *client, u16 reg, | |
| 55 | unsigned int len, u32 val) | |
| 56 | { | |
| 57 | u8 buf[6]; | |
| 58 | int ret; | |
| 59 | ||
| 60 | if (len > 4) | |
| 61 | return -EINVAL; | |
| 62 | ||
| 63 | put_unaligned_be16(reg, buf); | |
| 64 | put_unaligned_be32(val << (8 * (4 - len)), buf + 2); | |
| 65 | ret = i2c_master_send(client, buf, len + 2); | |
| 66 | if (ret != len + 2) { | |
| 67 | dev_err(&client->dev, "write error: reg=0x%4x: %d\n", reg, ret); | |
| 68 | return -EIO; | |
| 69 | } | |
| 70 | ||
| 71 | return 0; | |
| 72 | } | |
| 73 | ||
| 74 | #define ov_write_reg8(s, r, v) ov_write_reg(s, r, 1, v) | |
| 75 | #define ov_write_reg16(s, r, v) ov_write_reg(s, r, 2, v) | |
| 76 | #define ov_write_reg24(s, r, v) ov_write_reg(s, r, 3, v) | |
| 77 | ||
| 78 | static inline int ov_update_reg(struct i2c_client *client, u16 reg, u8 mask, u8 val) | |
| 79 | { | |
| 80 | u32 readval; | |
| 81 | int ret; | |
| 82 | ||
| 83 | ret = ov_read_reg8(client, reg, &readval); | |
| 84 | if (ret < 0) | |
| 85 | return ret; | |
| 86 | ||
| 87 | val = (readval & ~mask) | (val & mask); | |
| 88 | ||
| 89 | return ov_write_reg8(client, reg, val); | |
| 90 | } | |
| 91 | ||
| 92 | #endif |