From 770d465619423a946248018ea39ed9a74c8f2ff4 Mon Sep 17 00:00:00 2001 From: Alexandru Ardelean Date: Fri, 22 Nov 2019 15:24:12 +0200 Subject: [PATCH] iio: imu: adis: add unlocked read/write function versions This will allow more flexible control to group reads & writes into a single lock (particularly the state_lock). The end-goal is to remove the indio_dev->mlock usage, and the simplest fix would have been to just add another lock, which would not be a good idea on the long-run. Signed-off-by: Alexandru Ardelean Signed-off-by: Jonathan Cameron --- drivers/iio/imu/adis.c | 35 +++++------ include/linux/iio/imu/adis.h | 116 ++++++++++++++++++++++++++++++++++- 2 files changed, 130 insertions(+), 21 deletions(-) diff --git a/drivers/iio/imu/adis.c b/drivers/iio/imu/adis.c index db562fec79b2..2f518e6c727d 100644 --- a/drivers/iio/imu/adis.c +++ b/drivers/iio/imu/adis.c @@ -26,7 +26,14 @@ #define ADIS_MSC_CTRL_DATA_RDY_DIO2 BIT(0) #define ADIS_GLOB_CMD_SW_RESET BIT(7) -int adis_write_reg(struct adis *adis, unsigned int reg, +/** + * __adis_write_reg() - write N bytes to register (unlocked version) + * @adis: The adis device + * @reg: The address of the lower of the two registers + * @value: The value to write to device (up to 4 bytes) + * @size: The size of the @value (in bytes) + */ +int __adis_write_reg(struct adis *adis, unsigned int reg, unsigned int value, unsigned int size) { unsigned int page = reg / ADIS_PAGE_SIZE; @@ -70,8 +77,6 @@ int adis_write_reg(struct adis *adis, unsigned int reg, }, }; - mutex_lock(&adis->state_lock); - spi_message_init(&msg); if (adis->current_page != page) { @@ -96,8 +101,7 @@ int adis_write_reg(struct adis *adis, unsigned int reg, adis->tx[3] = value & 0xff; break; default: - ret = -EINVAL; - goto out_unlock; + return -EINVAL; } xfers[size].cs_change = 0; @@ -113,20 +117,18 @@ int adis_write_reg(struct adis *adis, unsigned int reg, adis->current_page = page; } -out_unlock: - mutex_unlock(&adis->state_lock); - return ret; } -EXPORT_SYMBOL_GPL(adis_write_reg); +EXPORT_SYMBOL_GPL(__adis_write_reg); /** - * adis_read_reg() - read 2 bytes from a 16-bit register + * __adis_read_reg() - read N bytes from register (unlocked version) * @adis: The adis device * @reg: The address of the lower of the two registers * @val: The value read back from the device + * @size: The size of the @val buffer */ -int adis_read_reg(struct adis *adis, unsigned int reg, +int __adis_read_reg(struct adis *adis, unsigned int reg, unsigned int *val, unsigned int size) { unsigned int page = reg / ADIS_PAGE_SIZE; @@ -166,7 +168,6 @@ int adis_read_reg(struct adis *adis, unsigned int reg, }, }; - mutex_lock(&adis->state_lock); spi_message_init(&msg); if (adis->current_page != page) { @@ -188,15 +189,14 @@ int adis_read_reg(struct adis *adis, unsigned int reg, spi_message_add_tail(&xfers[3], &msg); break; default: - ret = -EINVAL; - goto out_unlock; + return -EINVAL; } ret = spi_sync(adis->spi, &msg); if (ret) { dev_err(&adis->spi->dev, "Failed to read register 0x%02X: %d\n", reg, ret); - goto out_unlock; + return ret; } else { adis->current_page = page; } @@ -210,12 +210,9 @@ int adis_read_reg(struct adis *adis, unsigned int reg, break; } -out_unlock: - mutex_unlock(&adis->state_lock); - return ret; } -EXPORT_SYMBOL_GPL(adis_read_reg); +EXPORT_SYMBOL_GPL(__adis_read_reg); #ifdef CONFIG_DEBUG_FS diff --git a/include/linux/iio/imu/adis.h b/include/linux/iio/imu/adis.h index 100b5d1cebf1..38ebe41092e1 100644 --- a/include/linux/iio/imu/adis.h +++ b/include/linux/iio/imu/adis.h @@ -75,11 +75,123 @@ int adis_init(struct adis *adis, struct iio_dev *indio_dev, struct spi_device *spi, const struct adis_data *data); int adis_reset(struct adis *adis); -int adis_write_reg(struct adis *adis, unsigned int reg, +int __adis_write_reg(struct adis *adis, unsigned int reg, unsigned int val, unsigned int size); -int adis_read_reg(struct adis *adis, unsigned int reg, +int __adis_read_reg(struct adis *adis, unsigned int reg, unsigned int *val, unsigned int size); +/** + * __adis_write_reg_8() - Write single byte to a register (unlocked) + * @adis: The adis device + * @reg: The address of the register to be written + * @value: The value to write + */ +static inline int __adis_write_reg_8(struct adis *adis, unsigned int reg, + uint8_t val) +{ + return __adis_write_reg(adis, reg, val, 1); +} + +/** + * __adis_write_reg_16() - Write 2 bytes to a pair of registers (unlocked) + * @adis: The adis device + * @reg: The address of the lower of the two registers + * @value: Value to be written + */ +static inline int __adis_write_reg_16(struct adis *adis, unsigned int reg, + uint16_t val) +{ + return __adis_write_reg(adis, reg, val, 2); +} + +/** + * __adis_write_reg_32() - write 4 bytes to four registers (unlocked) + * @adis: The adis device + * @reg: The address of the lower of the four register + * @value: Value to be written + */ +static inline int __adis_write_reg_32(struct adis *adis, unsigned int reg, + uint32_t val) +{ + return __adis_write_reg(adis, reg, val, 4); +} + +/** + * __adis_read_reg_16() - read 2 bytes from a 16-bit register (unlocked) + * @adis: The adis device + * @reg: The address of the lower of the two registers + * @val: The value read back from the device + */ +static inline int __adis_read_reg_16(struct adis *adis, unsigned int reg, + uint16_t *val) +{ + unsigned int tmp; + int ret; + + ret = __adis_read_reg(adis, reg, &tmp, 2); + if (ret == 0) + *val = tmp; + + return ret; +} + +/** + * __adis_read_reg_32() - read 4 bytes from a 32-bit register (unlocked) + * @adis: The adis device + * @reg: The address of the lower of the two registers + * @val: The value read back from the device + */ +static inline int __adis_read_reg_32(struct adis *adis, unsigned int reg, + uint32_t *val) +{ + unsigned int tmp; + int ret; + + ret = __adis_read_reg(adis, reg, &tmp, 4); + if (ret == 0) + *val = tmp; + + return ret; +} + +/** + * adis_write_reg() - write N bytes to register + * @adis: The adis device + * @reg: The address of the lower of the two registers + * @value: The value to write to device (up to 4 bytes) + * @size: The size of the @value (in bytes) + */ +static inline int adis_write_reg(struct adis *adis, unsigned int reg, + unsigned int val, unsigned int size) +{ + int ret; + + mutex_lock(&adis->state_lock); + ret = __adis_write_reg(adis, reg, val, size); + mutex_unlock(&adis->state_lock); + + return ret; +} + +/** + * adis_read_reg() - read N bytes from register + * @adis: The adis device + * @reg: The address of the lower of the two registers + * @val: The value read back from the device + * @size: The size of the @val buffer + */ +static int adis_read_reg(struct adis *adis, unsigned int reg, + unsigned int *val, unsigned int size) +{ + int ret; + + mutex_lock(&adis->state_lock); + ret = __adis_read_reg(adis, reg, val, size); + mutex_unlock(&adis->state_lock); + + return ret; +} + /** * adis_write_reg_8() - Write single byte to a register * @adis: The adis device -- 2.39.5