nvmem uses regmap_raw_read/write apis to read/write data from providers,
regmap raw apis stopped working with recent kernels which removed raw
accessors on mmio bus. This resulted in broken nvmem for providers
which are based on regmap mmio bus. This issue can be fixed temporarly
by moving to other regmap apis, but we might hit same issue in future.
Moving to interfaces based on read/write callbacks from providers would
be more robust.
This patch removes regmap dependency from nvmem and introduces
read/write callbacks from the providers.
Without this patch nvmem providers like qfprom based on regmap mmio
bus would not work.
Reported-by: Rajendra Nayak <rjendra@qti.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The devres.o gets linked if HAS_IOMEM is present so on ARCH=um
allyesconfig (COMPILE_TEST) failed on many files with:
drivers/built-in.o: In function `mtk_thermal_probe':
mtk_thermal.c:(.text+0x394618): undefined reference to `devm_ioremap_resource'
The users of devm_ioremap_resource() which are compile-testable should
depend on HAS_IOMEM.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Possibly, provider driver initialization is later than
consumer driver. Use function subsys_initcall to initialize
NVMEM provider early to ensure NVMEM consumer doesn't need
to -EPROBE_DEFER.
Signed-off-by: Andrew-CT Chen <andrew-ct.chen@mediatek.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Older drivers made an 'eeprom' file available in the /sys device
directory. Have the NVMEM core provide this to retain backwards
compatibility.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Legacy AT24, AT25 EEPROMs are exported in sys so that only root can
read the contents. The EEPROMs may contain sensitive information. Add
a flag so the provide can indicate that NVMEM should also restrict
access to root only.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current code fails to nvmem_cell_drop(cells[0]) - even worse, if
the loop above fails already at i==0, we'll enter an essentially
infinite loop doing nvmem_cell_drop on cells[-1], cells[-2], ... which
is unlikely to end well.
Also, we're not freeing the temporary backing array cells on the error
path.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The qfprom is a little endian device, but so far we've been
relying on the regmap mmio bus handling this for us without
explicitly stating that fact. After commit 4a98da2164cf
(regmap-mmio: Use native endianness for read/write, 2015-10-29),
the regmap mmio bus will read/write with the __raw_*() IO
accessors, instead of using the readl/writel() APIs that do
proper byte swapping for little endian devices.
So if we're running on a big endian processor and haven't
specified the endianness explicitly in the regmap config or in
DT, we're going to switch from doing little endian byte swapping
to big endian accesses without byte swapping, leading to some
confusing results. Specify the endianness explicitly so that the
regmap core properly byte swaps the accesses for us.
Cc: Rajendra Nayak <rnayak@codeaurora.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Tyler Baker <tyler.baker@linaro.org>
Cc: Simon Arlott <simon@fire.lp0.eu>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nvmem providers have restrictions on register strides, so return error
when users attempt to read/write buffers with sizes which are less
than word size.
Without this patch the userspace would continue to try as it does not
get any error from the nvmem core, resulting in a hang or endless loop
in userspace.
Reported-by: Ariel D'Alessandro <ariel@vanguardiasur.com.ar>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1) Make the include file to sort from order
2) clean up the driver to make more readability
Let's clean up such trivial details.
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nvmem providers have restrictions on register strides, so return error
when users attempt to read/write buffers with sizes which are less
than word size.
Without this patch the userspace would continue to try as it does not
get any error from the nvmem core, resulting in a hang or endless loop
in userspace.
Reported-by: Ariel D'Alessandro <ariel@vanguardiasur.com.ar>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit adds support for NXP LPC18xx EEPROM memory found in NXP
LPC185x/3x and LPC435x/3x/2x/1x devices.
EEPROM size is 16384 bytes and it can be entirely read and
written/erased with 1 word (4 bytes) granularity. The last page
(128 bytes) contains the EEPROM initialization data and is not writable.
Erase/program time is less than 3ms. The EEPROM device requires a
~1500 kHz clock (min 800 kHz, max 1600 kHz) that is generated dividing
the system bus clock by the division factor, contained in the divider
register (minus 1 encoded).
EEPROM will be kept in Power Down mode except during read/write calls.
Signed-off-by: Ariel D'Alessandro <ariel@vanguardiasur.com.ar>
Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The sunxi_sid driver doesn't check for kmalloc return status before
derefencing the returned pointer, which could lead to a NULL pointer
dereference if kmalloc failed. Check for its return code to make sure it
deosn't happen.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A tmp buffer is allocated if cell->bit_offset || cell->nbits.
So the tmp buffer needs to be freed at the same condition to avoid leak.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's pointless to test (cell->bit_offset || cell->bit_offset).
nvmem_shift_read_buffer_in_place() should be called when
(cell->bit_offset || cell->nbits).
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch brings read-only support for the On-Chip OTP cells
in the i.MX23 and i.MX28 processor. The driver implements the
new NVMEM provider API.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>