> On Wed, 21 Jun 2017 21:21:28 +0200 > Lorenzo Bianconi <lorenzo.bianconi83@xxxxxxxxx> wrote: > >> Add open drain support in order to share requested IRQ line between >> st_lsm6dsx device and other peripherals >> >> Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@xxxxxx> > Issue when IRQF_RISING and open drain is set. > Hi Jonathan, > Otherwise looks good. >> --- >> drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c | 17 +++++++++++++++++ >> 1 file changed, 17 insertions(+) >> >> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c >> index 2a72acc6e049..e2737dc71b67 100644 >> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c >> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c >> @@ -31,6 +31,8 @@ >> #include <linux/iio/iio.h> >> #include <linux/iio/buffer.h> >> >> +#include <linux/platform_data/st_sensors_pdata.h> >> + >> #include "st_lsm6dsx.h" >> >> #define ST_LSM6DSX_REG_FIFO_THL_ADDR 0x06 >> @@ -39,6 +41,8 @@ >> #define ST_LSM6DSX_REG_FIFO_DEC_GXL_ADDR 0x08 >> #define ST_LSM6DSX_REG_HLACTIVE_ADDR 0x12 >> #define ST_LSM6DSX_REG_HLACTIVE_MASK BIT(5) >> +#define ST_LSM6DSX_REG_PP_OD_ADDR 0x12 >> +#define ST_LSM6DSX_REG_PP_OD_MASK BIT(4) >> #define ST_LSM6DSX_REG_FIFO_MODE_ADDR 0x0a >> #define ST_LSM6DSX_FIFO_MODE_MASK GENMASK(2, 0) >> #define ST_LSM6DSX_FIFO_ODR_MASK GENMASK(6, 3) >> @@ -417,6 +421,8 @@ static const struct iio_buffer_setup_ops st_lsm6dsx_buffer_ops = { >> >> int st_lsm6dsx_fifo_setup(struct st_lsm6dsx_hw *hw) >> { >> + struct device_node *np = hw->dev->of_node; >> + struct st_sensors_platform_data *pdata; >> struct iio_buffer *buffer; >> unsigned long irq_type; >> bool irq_active_low; >> @@ -444,6 +450,17 @@ int st_lsm6dsx_fifo_setup(struct st_lsm6dsx_hw *hw) >> if (err < 0) >> return err; >> >> + pdata = (struct st_sensors_platform_data *)hw->dev->platform_data; >> + if ((np && of_property_read_bool(np, "drive-open-drain")) || >> + (pdata && pdata->open_drain)) { >> + err = st_lsm6dsx_write_with_mask(hw, ST_LSM6DSX_REG_PP_OD_ADDR, >> + ST_LSM6DSX_REG_PP_OD_MASK, 1); >> + if (err < 0) >> + return err; >> + >> + irq_type |= IRQF_SHARED; >> + } >> + > In common with the mpu3050 which was the first driver in IIO to do open drain, > I think you need to think about precedence as we allow for IRQF_RISING > and IRQF_FALLING already. Open drain only allows for shared interrupts > if IRQF_FALLING (I think) >> err = devm_request_threaded_irq(hw->dev, hw->irq, >> st_lsm6dsx_handler_irq, >> st_lsm6dsx_handler_thread, > I have not got the difference between IRQF_RISING and IRQF_FALLING when the irq line is marked as shared (when open drain is enabled). Looking at the code, mpu3050 gyro sensor does not support shared interrupts with IRQF_RISING and IRQF_TRIGGER_HIGH. Is it a hw limitation? Speaking with digital designer, lsm6dsx series allows open drain mode even if the requested irq line is IRQF_TRIGGER_HIGH or IRQF_RISING, we need to add a pull-down resistor. Moreover ST framework already supports open drain if the requested interrupt is IRQF_RISING. Regards, Lorenzo -- UNIX is Sexy: who | grep -i blonde | talk; cd ~; wine; talk; touch; unzip; touch; strip; gasp; finger; gasp; mount; fsck; more; yes; gasp; umount; make clean; sleep -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html