| Message ID | 20210429122806.3814330-6-sean@geanix.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v4,1/6] iio: accel: add support for FXLS8962AF/FXLS8964AF accelerometers | expand |
On Thu, Apr 29, 2021 at 3:28 PM Sean Nyekjaer <sean@geanix.com> wrote: > > When flushing the hw fifo there is a bug in the I2C that prevents burst > reads of more than one sample pair. ... > - ret = regmap_raw_read(data->regmap, FXLS8962AF_BUF_X_LSB, buffer, > - total_length); > + if (i2c_verify_client(dev)) { > + /* > + * Due to errata bug: > + * E3: FIFO burst read operation error using I2C interface > + * We have to avoid burst reads on I2C.. > + */ > + for (i = 0; i < samples; i++) { > + ret = regmap_raw_read(data->regmap, FXLS8962AF_BUF_X_LSB, > + &buffer[i], > + sample_length); > + if (ret < 0) > + goto out; > + } Can you rather create a separate function called fxls8962af_i2c_raw_read_errata3() and use it here by simply if (i2c) ret = fxls8962af_i2c_raw_read_errata3(); else ret = regmap_raw_read(); ? > + } else { > + ret = regmap_raw_read(data->regmap, FXLS8962AF_BUF_X_LSB, buffer, > + total_length); > + }
diff --git a/drivers/iio/accel/fxls8962af-core.c b/drivers/iio/accel/fxls8962af-core.c index 2e863ef71a7d..e45c9e88bf6e 100644 --- a/drivers/iio/accel/fxls8962af-core.c +++ b/drivers/iio/accel/fxls8962af-core.c @@ -14,6 +14,7 @@ #include <linux/bits.h> #include <linux/bitfield.h> +#include <linux/i2c.h> #include <linux/module.h> #include <linux/of_irq.h> #include <linux/pm_runtime.h> @@ -631,11 +632,28 @@ static int fxls8962af_fifo_transfer(struct fxls8962af_data *data, { struct device *dev = regmap_get_device(data->regmap); int sample_length = 3 * sizeof(*buffer); - int ret; + int ret, i; int total_length = samples * sample_length; - ret = regmap_raw_read(data->regmap, FXLS8962AF_BUF_X_LSB, buffer, - total_length); + if (i2c_verify_client(dev)) { + /* + * Due to errata bug: + * E3: FIFO burst read operation error using I2C interface + * We have to avoid burst reads on I2C.. + */ + for (i = 0; i < samples; i++) { + ret = regmap_raw_read(data->regmap, FXLS8962AF_BUF_X_LSB, + &buffer[i], + sample_length); + if (ret < 0) + goto out; + } + } else { + ret = regmap_raw_read(data->regmap, FXLS8962AF_BUF_X_LSB, buffer, + total_length); + } + + out: if (ret < 0) dev_err(dev, "Error transferring data from fifo: %d\n", ret);
When flushing the hw fifo there is a bug in the I2C that prevents burst reads of more than one sample pair. Signed-off-by: Sean Nyekjaer <sean@geanix.com> --- Changes from RFC: - using i2c_verify_client() to detect if hw is connected on I2C bus drivers/iio/accel/fxls8962af-core.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-)