lkml.org 
[lkml]   [2019]   [Oct]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 02/10] iio: imu: adis: add unlocked read/write function versions
On Thu, 26 Sep 2019 14:18:04 +0300
Alexandru Ardelean <alexandru.ardelean@analog.com> wrote:

> 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 <alexandru.ardelean@analog.com>
Applied to the togreg branch of iio.git and pushed out as testing etc.

Jonathan

> ---
> drivers/iio/imu/adis.c | 34 +++++------
> include/linux/iio/imu/adis.h | 114 ++++++++++++++++++++++++++++++++++-
> 2 files changed, 128 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/iio/imu/adis.c b/drivers/iio/imu/adis.c
> index 3c2d896e3a96..4f3be011c898 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;
> @@ -188,15 +190,14 @@ 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 +211,9 @@ 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 3ed5eceaac2d..3a028c40e04e 100644
> --- a/include/linux/iio/imu/adis.h
> +++ b/include/linux/iio/imu/adis.h
> @@ -75,11 +75,121 @@ 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 version)
> + * @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 version)
> + * @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 version)
> + * @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 version)
> + * @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);
> + *val = tmp;
> +
> + return ret;
> +}
> +
> +/**
> + * __adis_read_reg_32() - read 4 bytes from a 32-bit 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
> + */
> +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);
> + *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

\
 
 \ /
  Last update: 2019-10-06 11:13    [W:0.139 / U:1.140 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site