1 /* SPDX-License-Identifier: GPL-2.0 */
3 * MIPI Camera Control Interface (CCI) register access helpers.
5 * Copyright (C) 2023 Hans de Goede <hansg@kernel.org>
10 #include <linux/bitfield.h>
11 #include <linux/bits.h>
12 #include <linux/types.h>
18 * struct cci_reg_sequence - An individual write from a sequence of CCI writes
20 * @reg: Register address, use CCI_REG#() macros to encode reg width
21 * @val: Register value
23 * Register/value pairs for sequences of writes.
25 struct cci_reg_sequence {
31 * Macros to define register address with the register width encoded
32 * into the higher bits.
34 #define CCI_REG_ADDR_MASK GENMASK(15, 0)
35 #define CCI_REG_WIDTH_SHIFT 16
36 #define CCI_REG_WIDTH_MASK GENMASK(19, 16)
38 #define CCI_REG_WIDTH_BYTES(x) FIELD_GET(CCI_REG_WIDTH_MASK, x)
39 #define CCI_REG_WIDTH(x) (CCI_REG_WIDTH_BYTES(x) << 3)
40 #define CCI_REG_ADDR(x) FIELD_GET(CCI_REG_ADDR_MASK, x)
41 #define CCI_REG_LE BIT(20)
43 #define CCI_REG8(x) ((1 << CCI_REG_WIDTH_SHIFT) | (x))
44 #define CCI_REG16(x) ((2 << CCI_REG_WIDTH_SHIFT) | (x))
45 #define CCI_REG24(x) ((3 << CCI_REG_WIDTH_SHIFT) | (x))
46 #define CCI_REG32(x) ((4 << CCI_REG_WIDTH_SHIFT) | (x))
47 #define CCI_REG64(x) ((8 << CCI_REG_WIDTH_SHIFT) | (x))
48 #define CCI_REG16_LE(x) (CCI_REG_LE | (2U << CCI_REG_WIDTH_SHIFT) | (x))
49 #define CCI_REG24_LE(x) (CCI_REG_LE | (3U << CCI_REG_WIDTH_SHIFT) | (x))
50 #define CCI_REG32_LE(x) (CCI_REG_LE | (4U << CCI_REG_WIDTH_SHIFT) | (x))
51 #define CCI_REG64_LE(x) (CCI_REG_LE | (8U << CCI_REG_WIDTH_SHIFT) | (x))
54 * cci_read() - Read a value from a single CCI register
56 * @map: Register map to read from
57 * @reg: Register address to read, use CCI_REG#() macros to encode reg width
58 * @val: Pointer to store read value
59 * @err: Optional pointer to store errors, if a previous error is set
60 * then the read will be skipped
62 * Return: %0 on success or a negative error code on failure.
64 int cci_read(struct regmap *map, u32 reg, u64 *val, int *err);
67 * cci_write() - Write a value to a single CCI register
69 * @map: Register map to write to
70 * @reg: Register address to write, use CCI_REG#() macros to encode reg width
71 * @val: Value to be written
72 * @err: Optional pointer to store errors, if a previous error is set
73 * then the write will be skipped
75 * Return: %0 on success or a negative error code on failure.
77 int cci_write(struct regmap *map, u32 reg, u64 val, int *err);
80 * cci_update_bits() - Perform a read/modify/write cycle on
81 * a single CCI register
83 * @map: Register map to update
84 * @reg: Register address to update, use CCI_REG#() macros to encode reg width
85 * @mask: Bitmask to change
86 * @val: New value for bitmask
87 * @err: Optional pointer to store errors, if a previous error is set
88 * then the update will be skipped
90 * Note this uses read-modify-write to update the bits, atomicity with regards
91 * to other cci_*() register access functions is NOT guaranteed.
93 * Return: %0 on success or a negative error code on failure.
95 int cci_update_bits(struct regmap *map, u32 reg, u64 mask, u64 val, int *err);
98 * cci_multi_reg_write() - Write multiple registers to the device
100 * @map: Register map to write to
101 * @regs: Array of structures containing register-address, -value pairs to be
102 * written, register-addresses use CCI_REG#() macros to encode reg width
103 * @num_regs: Number of registers to write
104 * @err: Optional pointer to store errors, if a previous error is set
105 * then the write will be skipped
107 * Write multiple registers to the device where the set of register, value
108 * pairs are supplied in any order, possibly not all in a single range.
110 * Use of the CCI_REG#() macros to encode reg width is mandatory.
112 * For raw lists of register-address, -value pairs with only 8 bit
113 * wide writes regmap_multi_reg_write() can be used instead.
115 * Return: %0 on success or a negative error code on failure.
117 int cci_multi_reg_write(struct regmap *map, const struct cci_reg_sequence *regs,
118 unsigned int num_regs, int *err);
120 #if IS_ENABLED(CONFIG_V4L2_CCI_I2C)
122 * devm_cci_regmap_init_i2c() - Create regmap to use with cci_*() register
125 * @client: i2c_client to create the regmap for
126 * @reg_addr_bits: register address width to use (8 or 16)
128 * Note the memory for the created regmap is devm() managed, tied to the client.
130 * Return: %0 on success or a negative error code on failure.
132 struct regmap *devm_cci_regmap_init_i2c(struct i2c_client *client,