Ian Lepore 844aff82a6 Allow i2c bus speed to be configured via hints, FDT data, and sysctl. ... The current support for controlling i2c bus speed is an inconsistant mess. There are 4 symbolic speed values defined, UNKNOWN, SLOW, FAST, FASTEST. It seems to be universally assumed that SLOW means the standard 100KHz rate from the original spec. Nothing ever calls iicbus_reset() with a speed of FAST, although some drivers would treat it as the 400KHz standard speed. Mostly iicbus_reset() is called with the speed set to UNKNOWN or FASTEST, and there's really no telling what any individual driver will do with those. The speed of an i2c bus is limited by the speed of the slowest device on the bus. This means that generally the bus speed needs to be configured based on the board/system and the components within it. Historically for i2c we've configured with device hints. Newer systems use FDT data and it documents a clock-frequency property for i2c busses. Hobbyists and developers are likely to want on the fly changes. These changes provide all 3 methods, but do not require any existing drivers to change to use the new facilities. This adds an iicbus method, iicbus_get_frequency(dev, speed) that gets the frequency for the requested symbolic speed. If the symbolic speed is SLOW or if there is no speed configured for the bus, the returned value is 100KHz, always. Otherwise, if bus speed is configured by hints, fdt, tunable, or sysctl, that speed is returned. It also adds a helper function, iicbus_init_frequency() that any bus driver subclassed from iicbus can initialize the frequency from some other source of info. Initial driver implementations are provided for Freescale and TI. Differential Revision: https://reviews.freebsd.org/D1174 PR: 195009		2014-11-18 01:54:31 +00:00
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allwinner	Make the GPIO children attach to the first unit available and not only to	2014-10-28 18:33:59 +00:00
altera/socfpga	Provide a character device allowing us to access BERI memory regions.	2014-10-22 11:30:03 +00:00
arm	No functional changes. Remove a couple outdated or inane comments and	2014-11-16 21:39:56 +00:00
at91	Remove the ARM_DEVICE_MULTIPASS option and make its effect be the default.	2014-10-26 18:30:35 +00:00
broadcom/bcm2835	Fix the error checking, broken on r273337, to _not_ ignore controller	2014-11-12 03:07:46 +00:00
cavium/cns11xx	Mechanically convert to if_inc_counter().	2014-09-19 09:20:16 +00:00
conf	Renove faith(4) and faithd(8) from base. It looks like industry	2014-11-09 21:33:01 +00:00
freescale	Allow i2c bus speed to be configured via hints, FDT data, and sysctl.	2014-11-18 01:54:31 +00:00
include	Add fueword(9) and casueword(9) functions. They are like fuword(9)	2014-10-28 15:22:13 +00:00
lpc	Make the GPIO children attach to the first unit available and not only to	2014-10-28 18:33:59 +00:00
mv
rockchip	Make the GPIO children attach to the first unit available and not only to	2014-10-28 18:33:59 +00:00
samsung	Make the GPIO children attach to the first unit available and not only to	2014-10-28 18:33:59 +00:00
ti	Allow i2c bus speed to be configured via hints, FDT data, and sysctl.	2014-11-18 01:54:31 +00:00
versatile	Move if_smc_fdt.c to live in sys/dev/smc. It's not specific to the ARM	2014-09-10 10:59:17 +00:00
xilinx	Make the GPIO children attach to the first unit available and not only to	2014-10-28 18:33:59 +00:00
xscale	Make the GPIO children attach to the first unit available and not only to	2014-10-28 18:33:59 +00:00