Messages in this thread | | | Subject | Re: [PATCH v2 1/2] iio: ina2xx: add support for TI INA2xx Power Monitors | From | Marc Titinger <> | Date | Wed, 2 Dec 2015 18:09:40 +0100 |
| |
On 02/12/2015 17:44, Guenter Roeck wrote: > On 12/02/2015 08:20 AM, Marc Titinger wrote: >> On 02/12/2015 17:04, Guenter Roeck wrote: >>> On 12/02/2015 02:20 AM, Marc Titinger wrote: >>>> On 02/12/2015 03:14, Guenter Roeck wrote: >>>>> On Mon, Nov 30, 2015 at 12:49:14PM +0100, Marc Titinger wrote: >>>>>> in SOFTWARE buffer mode, a kthread will capture the active >>>>>> scan_elements >>>>>> into a kfifo, then compute the remaining time until the next capture >>>>>> tick >>>>>> and do an active wait (udelay). >>>>>> >>>>>> This will produce a stream of up to fours channels plus a 64bits >>>>>> timestamps (ns). >>>>>> >>>>>> Tested with ina226, on BeagleBoneBlack. >>>>>> >>>>>> Datasheet: http://www.ti.com/lit/gpn/ina226 >>>>>> >>>>>> Signed-off-by: Marc Titinger <mtitinger@baylibre.com> >>>>>> --- >>>>>> drivers/iio/adc/Kconfig | 9 + >>>>>> drivers/iio/adc/Makefile | 1 + >>>>>> drivers/iio/adc/ina2xx-iio.c | 678 >>>>>> +++++++++++++++++++++++++++++++++++++++++++ >>>>>> 3 files changed, 688 insertions(+) >>>>>> create mode 100644 drivers/iio/adc/ina2xx-iio.c >>>>>> + >>>>> [ ... ] >>>>>> + >>>>>> +static const struct i2c_device_id ina2xx_id[] = { >>>>>> + {"ina219", ina219}, >>>>>> + {"ina220", ina219}, >>>>>> + {"ina226", ina226}, >>>>>> + {"ina230", ina226}, >>>>>> + {"ina231", ina226}, >>>>>> + {} >>>>>> +}; >>>>> >>>>> I wonder what is going to happen if both this driver and the hwmon >>>>> driver for the same chips are configured in a system which supports >>>>> devicetree (or any system, really). Unless I am missing something, >>>>> the result will be that both drivers will try to instantiate, and >>>>> one will fail with -EBUSY. Or the instantiated driver is more or less >>>>> random, depending on which one happens to be loaded. Not a good >>>>> situation to be in. >>>> >>>> I agree, we should put a mutual exclusion in Kconfig, plus maybe a >>>> cross-reference in the help section. >>>> >>>>> >>>>> For the time being, it might make sense to add cross-dependencies >>>>> in Kconfig to only permit one of the two drivers to be configured. >>>>> >>>>> Ultimately we may need a better solution for the iio-hwmon bridge, >>>>> one that makes the underlying driver transparent in both devicetree >>>>> properties and user space ABI. No idea how to do that, though. >>>>> >>>> >>>> IDK if ina2xx is a special case or if this matter of dual driver >>>> stacks for the same chip already occurred and requires specific >>>> plumbing. Making the user aware of the mutual of the exclusion sounds >>>> fine with me. >>>> >>> htu21. We'll drop that driver from hwmon with the 4.5 kernel. >>> We could just drop ina2xx as well, but it is more widely used >>> and referenced from dts files. The ABI changes, so I am not sure >>> if we can just do that. >> >> I changed iio/adc/Kconfig to the following: >> >> +config INA2XX_ADC >> + tristate "Texas Instruments INA2xx Power Monitors IIO driver" >> + depends on I2C && !SENSORS_INA2XX >> + select REGMAP_I2C >> + select IIO_BUFFER >> + select IIO_KFIFO_BUF >> + help >> + Say yes here to build support for TI INA2xx family of Power >> Monitors. >> + This driver is mutually exclusive with the HWMON version. >> + >> >> >> anything the patch should also add to hwmon/Kconfig (that will not >> lead to a cycling reference warning) ? >> > > You could try the opposite, but I don't know if that works. > > depends on I2C && !INA2XX_ADC
I tried: it's functional, but leads to a ugly warning:
drivers/iio/adc/Kconfig:173:error: recursive dependency detected! drivers/iio/adc/Kconfig:173: symbol INA2XX_ADC depends on SENSORS_INA2XX drivers/hwmon/Kconfig:1453: symbol SENSORS_INA2XX depends on INA2XX_ADC
Anyone knows how to implement a radio button in Kconfig ? ;)
> > Guenter >
| |