On Thu, Jan 15, 2015 at 01:12:17AM -0800, David E. Box wrote: > This patch implements an I2C bus sharing mechanism between the host and platform > hardware on select Intel BayTrail SoC platforms using the X-Powers AXP288 PMIC. > > On these platforms access to the PMIC must be shared with platform hardware. The > hardware unit assumes full control of the I2C bus and the host must request > access through a special semaphore. Hardware control of the bus also makes it > necessary to disable runtime pm to avoid interfering with hardware transactions. > > Signed-off-by: David E. Box <david.e.box@xxxxxxxxxxxxxxx> Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> One comment, though: > --- > drivers/i2c/busses/Kconfig | 11 ++ > drivers/i2c/busses/Makefile | 1 + > drivers/i2c/busses/i2c-designware-baytrail.c | 160 +++++++++++++++++++++++++++ > drivers/i2c/busses/i2c-designware-core.h | 6 + > drivers/i2c/busses/i2c-designware-platdrv.c | 20 +++- > 5 files changed, 193 insertions(+), 5 deletions(-) > create mode 100644 drivers/i2c/busses/i2c-designware-baytrail.c > > diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig > index 917c358..9a83c46 100644 > --- a/drivers/i2c/busses/Kconfig > +++ b/drivers/i2c/busses/Kconfig > @@ -464,6 +464,17 @@ config I2C_DESIGNWARE_PCI > This driver can also be built as a module. If so, the module > will be called i2c-designware-pci. > > +config I2C_DESIGNWARE_BAYTRAIL > + bool "Intel Baytrail I2C semaphore support" It would be nice if it was possible to compile this as a module. > + depends on I2C_DESIGNWARE_PLATFORM > + select IOSF_MBI > + help > + This driver enables managed host access to the PMIC I2C bus on select > + Intel BayTrail platforms using the X-Powers AXP288 PMIC. It allows > + the host to request uninterrupted access to the PMIC's I2C bus from > + the platform firmware controlling it. You should say Y if running on > + a BayTrail system using the AXP288. > + -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
