As reported in the links given below. the BCM2835 has a hardware bug in
its i2c module which prevents a correct clock stretching. This patch
adds the I2C_AQ_NO_CLK_STRETCH quirk flag to i2c-bcm2835.
Signed-off-by: Nicola Corna <nicola@corna.info>
[wsa: put the links into the code as comments]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Checks if the cdiv value is in between min (0x2) and max (0xFFFE)
supported values by the bcm2835. If not, it returns -ENODEV.
See page 33/34 of BCM2835-ARM-Peripherals.pdf for the DIV register.
https://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
Signed-off-by: Silvan Wicki <linux_wi@tinag.ch>
[wsa: resolved a merge conflict]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The datasheet mentions on page 31 that the bits 10-31 must be read as
don't care and written as 0.
https://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
We cannot guarantee that we read bits 10-31 as always 0 (because the
datasheet says read as don't care). We clear the bits with a bitmask to
prevent writing back unknown data at the reserved bits.
Signed-off-by: Silvan Wicki <linux_wi@tinag.ch>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
return type of wait_for_completion_timeout is unsigned long not int. as
time_left is used for wait_for_completion_timeout exclusively here its
type is simply changed to unsigned long.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This driver has been flagged to drop class based instantiation. The removal
improves boot-up time and is unneeded for embedded controllers. Users have been
warned to switch for some time now, so we can actually do the removal. Keep the
DEPRECATED flag, so the core can inform users that the behaviour finally
changed now. After another transition period, this flag can go, too.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message. For example,
k.alloc and v.alloc failures use dump_stack().
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Felipe Balbi <balbi@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Use devm_ioremap_resource() in order to make the code simpler,
and remove redundant return value check of platform_get_resource()
because the value is checked by devm_ioremap_resource().
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In order to find I2C devices in the device tree, the platform nodes
have to be known by the I2C core. This requires setting the
dev.of_node parameter of the adapter.
Signed-off-by: Florian Meier <florian.meier@koalo.de>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.
[akpm@linux-foundation.org: linux-next resyncs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This implements a very basic I2C host driver for the BCM2835 SoC. Missing
features so far are:
* 10-bit addressing.
* DMA.
Reviewed-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
