diff options
Diffstat (limited to 'drivers/media/v4l2-core/v4l2-cci.c')
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-cci.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/v4l2-cci.c b/drivers/media/v4l2-core/v4l2-cci.c new file mode 100644 index 000000000000..bc2dbec019b0 --- /dev/null +++ b/drivers/media/v4l2-core/v4l2-cci.c @@ -0,0 +1,166 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * MIPI Camera Control Interface (CCI) register access helpers. + * + * Copyright (C) 2023 Hans de Goede <hansg@kernel.org> + */ + +#include <linux/bitfield.h> +#include <linux/delay.h> +#include <linux/dev_printk.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/types.h> + +#include <asm/unaligned.h> + +#include <media/v4l2-cci.h> + +int cci_read(struct regmap *map, u32 reg, u64 *val, int *err) +{ + unsigned int len; + u8 buf[8]; + int ret; + + if (err && *err) + return *err; + + len = FIELD_GET(CCI_REG_WIDTH_MASK, reg); + reg = FIELD_GET(CCI_REG_ADDR_MASK, reg); + + ret = regmap_bulk_read(map, reg, buf, len); + if (ret) { + dev_err(regmap_get_device(map), "Error reading reg 0x%4x: %d\n", + reg, ret); + goto out; + } + + switch (len) { + case 1: + *val = buf[0]; + break; + case 2: + *val = get_unaligned_be16(buf); + break; + case 3: + *val = get_unaligned_be24(buf); + break; + case 4: + *val = get_unaligned_be32(buf); + break; + case 8: + *val = get_unaligned_be64(buf); + break; + default: + dev_err(regmap_get_device(map), "Error invalid reg-width %u for reg 0x%04x\n", + len, reg); + ret = -EINVAL; + break; + } + +out: + if (ret && err) + *err = ret; + + return ret; +} +EXPORT_SYMBOL_GPL(cci_read); + +int cci_write(struct regmap *map, u32 reg, u64 val, int *err) +{ + unsigned int len; + u8 buf[8]; + int ret; + + if (err && *err) + return *err; + + len = FIELD_GET(CCI_REG_WIDTH_MASK, reg); + reg = FIELD_GET(CCI_REG_ADDR_MASK, reg); + + switch (len) { + case 1: + buf[0] = val; + break; + case 2: + put_unaligned_be16(val, buf); + break; + case 3: + put_unaligned_be24(val, buf); + break; + case 4: + put_unaligned_be32(val, buf); + break; + case 8: + put_unaligned_be64(val, buf); + break; + default: + dev_err(regmap_get_device(map), "Error invalid reg-width %u for reg 0x%04x\n", + len, reg); + ret = -EINVAL; + goto out; + } + + ret = regmap_bulk_write(map, reg, buf, len); + if (ret) + dev_err(regmap_get_device(map), "Error writing reg 0x%4x: %d\n", + reg, ret); + +out: + if (ret && err) + *err = ret; + + return ret; +} +EXPORT_SYMBOL_GPL(cci_write); + +int cci_update_bits(struct regmap *map, u32 reg, u64 mask, u64 val, int *err) +{ + u64 readval; + int ret; + + ret = cci_read(map, reg, &readval, err); + if (ret) + return ret; + + val = (readval & ~mask) | (val & mask); + + return cci_write(map, reg, val, err); +} +EXPORT_SYMBOL_GPL(cci_update_bits); + +int cci_multi_reg_write(struct regmap *map, const struct cci_reg_sequence *regs, + unsigned int num_regs, int *err) +{ + unsigned int i; + int ret; + + for (i = 0; i < num_regs; i++) { + ret = cci_write(map, regs[i].reg, regs[i].val, err); + if (ret) + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(cci_multi_reg_write); + +#if IS_ENABLED(CONFIG_V4L2_CCI_I2C) +struct regmap *devm_cci_regmap_init_i2c(struct i2c_client *client, + int reg_addr_bits) +{ + struct regmap_config config = { + .reg_bits = reg_addr_bits, + .val_bits = 8, + .reg_format_endian = REGMAP_ENDIAN_BIG, + .disable_locking = true, + }; + + return devm_regmap_init_i2c(client, &config); +} +EXPORT_SYMBOL_GPL(devm_cci_regmap_init_i2c); +#endif + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Hans de Goede <hansg@kernel.org>"); +MODULE_DESCRIPTION("MIPI Camera Control Interface (CCI) support"); |