On Sun, 6 Oct 2019 10:12:01 +0100 Jonathan Cameron <jic23@xxxxxxxxxx> wrote: > On Thu, 26 Sep 2019 14:18:04 +0300 > Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> 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@xxxxxxxxxx> > Applied to the togreg branch of iio.git and pushed out as testing etc. > > Jonathan > 0-day found a potential issue (kind of) in the read functions. > > --- > > 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); Zero day isn't happy that this can use tmp without it actually being set in the __adis_read_reg. I've added if (ret) return ret; > > + *val = tmp; > > + > > + return ret; and changed this to return 0; Same in the 32bit case below. Hmm. There are quite a few sparse warnings in the adis16400 if anyone fancies cleaning them up ;) Thanks, Jonathan > > +} > > + > > +/** > > + * __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 >