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The structure stm32f7_setup is local to the source and does not need
to be in global scope, make it static const.
Cleans up sparse warning:
symbol 'stm32f7_setup' was not declared. Should it be static?
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Make sure (of/i2c/platform)_device_id tables are NULL terminated.
Found by coccinelle spatch "misc/of_table.cocci"
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Add PCI ID for Intel Cedar Fork PCH.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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I2C drive setup structure is not properly allocated.
Make it static instead of pointer to store driver data.
Fixes: aeb068c5721485 ("i2c: i2c-stm32f7: add driver")
Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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As reported by Rajat Jain, there are problems when ACPI operation
region handlers or similar, called at the ->resume_early() time, for
I2C client devices try to access an I2C controller that has already
been suspended at that point. To avoid that, move the suspend/resume
of i2c-designware-platdrv to the late/early stages, respectively.
While at it, avoid resuming the device from runtime suspend in the
driver's ->suspend callback which isn't particularly nice. [A better
approach would be to make the driver track the PM state of the device
so that it doesn't need to resume it in ->suspend, so implement it.]
First, drop dw_i2c_plat_suspend() added by commit a23318feeff6 (i2c:
designware: Fix system suspend) and rename dw_i2c_plat_runtime_suspend()
back to dw_i2c_plat_suspend().
Second, point the driver's ->late_suspend and ->early_resume
callbacks, rather than its ->suspend and ->resume callbacks,
to dw_i2c_plat_suspend() and dw_i2c_plat_resume(), respectively,
so that they are not executed in parallel with each other, for
example if runtime resume of the device takes place during system
suspend.
Finally, add "suspended" and "skip_resume" flags to struct dw_i2c_dev
and make dw_i2c_plat_suspend() and dw_i2c_plat_resume() use them to
avoid suspending or resuming the device twice in a row and to avoid
resuming a previously runtime-suspended device during system resume.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Johannes Stezenbach <js@sig21.net>
Tested-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The power management handling in dw_i2c_plat_probe() is somewhat
messy and it is rather hard to figure out the code intention for
the case when pm_disabled is set. In that case, the driver doesn't
enable runtime PM at all, but in addition to that it calls
pm_runtime_forbid() as though it wasn't sure if runtime PM might
be enabled for the device later by someone else.
Although that concern doesn't seem to be actually valid, the
device is clearly still expected to be PM-capable even in the
pm_disabled set case, so a better approach would be to enable
runtime PM for it unconditionally and prevent it from being
runtime-suspended by using pm_runtime_get_noresume().
Make the driver do that.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Update my imgtec.com and personal email address to my kernel.org one in
a few places as MIPS will soon no longer be part of Imagination
Technologies, and add mappings in .mailcap so get_maintainer.pl reports
the right address.
Signed-off-by: James Hogan <jhogan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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This patch adds initial support for the STM32F7 I2C controller.
Signed-off-by: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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This patch uses a more generic definition of speed enum for i2c-stm32f4
driver.
Signed-off-by: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Reviewed-by: Ludovic BARRE <ludovic.barre@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Add driver support for the Altera I2C Controller. The I2C
controller is soft IP for use in FPGAs.
Signed-off-by: Thor Thayer <thor.thayer@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
- new drivers for Spreadtrum I2C, Intel Cherry Trail Whiskey Cove SMBUS
- quite some driver updates
- cleanups for the i2c-mux subsystem
- some subsystem-wide constification
- further cleanup of include/linux/i2c
* 'i2c/for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (50 commits)
i2c: sprd: Fix undefined reference errors
i2c: nomadik: constify amba_id
i2c: versatile: Make i2c_algo_bit_data const
i2c: busses: make i2c_adapter_quirks const
i2c: busses: make i2c_adapter const
i2c: busses: make i2c_algorithm const
i2c: Add Spreadtrum I2C controller driver
dt-bindings: i2c: Add Spreadtrum I2C controller documentation
i2c-cht-wc: make cht_wc_i2c_adap_driver static
MAINTAINERS: Add entry for drivers/i2c/busses/i2c-cht-wc.c
i2c: aspeed: Retain delay/setup/hold values when configuring bus frequency
dt-bindings: i2c: eeprom: Document vendor to be used and deprecated ones
i2c: i801: Restore the presence state of P2SB PCI device after reading BAR
MAINTAINERS: drop entry for Blackfin I2C and Sonic's email
blackfin: merge the two TWI header files
i2c: davinci: Preserve return value of devm_clk_get
i2c: mediatek: Add i2c compatible for MediaTek MT7622
dt-bindings: i2c: Add MediaTek MT7622 i2c binding
dt-bindings: i2c: modify information formats
i2c: mux: i2c-arb-gpio-challenge: allow compiling w/o OF support
...
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Since the i2c driver of Spreadtrum can not be build as one module, thus
it should depend on CONFIG_I2C is build in.
Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The Lenovo Miix2 8 DSDT contains an i2c clk / bus speed of 1700000 Hz
for one if its devices, which is not supported.
This is the second DSDT to show up with an unsupported clk in a short
time, remove the hardcoded fix for DSDTs with a 1 MiHz clock and simply
always round down the clk to the nearest supported value.
Reported-by: russianneuromancer@ya.ru
Fixes: 682c6c2188 ("i2c: designware: Some broken DSTDs use 1MiHz ...")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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amba_id are not supposed to change at runtime. All functions
working with const amba_id. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Make this const as it is only used in a copy operation.
Done using Coccinelle.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Make these const as they are only stored as a reference in the quirks
field of an i2c_adapter structure, which is const. Done using
Coccinelle.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Make these const as they are only used in a copy operation.
Done using Coccinelle.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: David Daney <david.daney@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Make these const as they are only stored in the algo field of
i2c_adapter structure, which is const.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Compare the number of bytes actually seen on the wire to the byte
count field returned by the slave device.
Previously we just overwrote the byte count returned by the slave
with the real byte count and let the caller figure out if the
message was sane.
Signed-off-by: Stephen Douthit <stephend@adiengineering.com>
Tested-by: Dan Priamo <danp@adiengineering.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
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According to Table 15-14 of the C2000 EDS (Intel doc #510524) the
rx data pointed to by the descriptor dptr contains the byte count.
desc->rxbytes reports all bytes read on the wire, including the
"byte count" byte. So if a device sends 4 bytes in response to a
block read, on the wire and in the DMA buffer we see:
count data1 data2 data3 data4
0x04 0xde 0xad 0xbe 0xef
That's what we want to return in data->block to the next level.
Instead we were actually prefixing that with desc->rxbytes:
bad
count count data1 data2 data3 data4
0x05 0x04 0xde 0xad 0xbe 0xef
This was discovered while developing a BMC solution relying on the
ipmi_ssif.c driver which was trying to interpret the bogus length
field as part of the IPMI response.
Signed-off-by: Stephen Douthit <stephend@adiengineering.com>
Tested-by: Dan Priamo <danp@adiengineering.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
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This patch adds the I2C controller driver for Spreadtrum SC9860 platform.
Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The structure cht_wc_i2c_adap_driver is local to the source
and does not need to be in global scope, so make it static.
Cleans up sparse warning:
symbol 'cht_wc_i2c_adap_driver' was not declared. Should it be static?
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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In addition to the base, low and high clock configuration, the AC timing
register #1 on the AST2400 houses fields controlling:
1. tBUF: Minimum delay between Stop and Start conditions
2. tHDSTA: Hold time for the Start condition
3. tACST: Setup time for Start and Stop conditions, and hold time for the
Repeated Start condition
These values are defined in hardware on the AST2500 and therefore don't
need to be set.
aspeed_i2c_init_clk() was performing a direct write of the generated
clock values rather than a read/mask/modify/update sequence to retain
tBUF, tHDSTA and tACST, and therefore cleared the tBUF, tHDSTA and tACST
fields on the AST2400. This resulted in a delay/setup/hold time of 1
base clock, which in some configurations is not enough for some devices
(e.g. the MAX31785 fan controller, with an APB of 48MHz and a desired
bus speed of 100kHz).
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Sun, Yunying reported the following failure on Denverton micro-server:
EDAC DEBUG: pnd2_init:
EDAC DEBUG: pnd2_probe:
EDAC DEBUG: dnv_rd_reg: Read b_cr_tolud_pci=00000000_80000000
EDAC DEBUG: dnv_rd_reg: Read b_cr_touud_lo_pci=00000000_80000000
EDAC DEBUG: dnv_rd_reg: Read b_cr_touud_hi_pci=00000000_00000004
EDAC DEBUG: dnv_rd_reg: Read b_cr_asym_mem_region0_mchbar=00000000_00000000
EDAC DEBUG: dnv_rd_reg: Read b_cr_asym_mem_region1_mchbar=00000000_00000000
EDAC DEBUG: dnv_rd_reg: Read b_cr_mot_out_base_mchbar=00000000_00000000
EDAC DEBUG: dnv_rd_reg: Read b_cr_mot_out_mask_mchbar=00000000_00000000
EDAC pnd2: Failed to register device with error -19.
On Denverton micro-server, the presence of the P2SB bridge PCI device is
enabled or disabled by the item 'RelaxSecConf' in BIOS setup menu. When
'RelaxSecConf' is enabled, the P2SB PCI device is present and the pnd2_edac
EDAC driver also uses it to get BAR. Hiding the P2SB PCI device caused the
pnd2_edac EDAC driver failed to get BAR then reported the above failure.
Therefor, store the presence state of P2SB PCI device before unhiding it
for reading BAR and restore the presence state after reading BAR.
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Reported-by: Yunying Sun <yunying.sun@intel.com>
Tested-by: Yunying Sun <yunying.sun@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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There seems to be no need for separate ones since all users include both
files anyhow. Merge them because include/linux/i2c is to be deprecated.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The i2c driver can run into driver dependency issues if its loaded
before a clock driver it depends on. Therefore, EPROBE_DEFER may be
returned by devm_clk_get and should be returned in probe to allow the
kernel to reprobe the driver at a later time. This patch allows the error
value returned by devm_clk_get to be passed through and not overwritten.
Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Add i2c compatible for MT7622. Compare to MT8173 i2c controller,
MT7622 limits message numbers to 255, and does not support 4GB
DMA mode.
Signed-off-by: Jun Gao <jun.gao@mediatek.com>
Reviewed-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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i2c/for-4.14
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It simplifies some tests.
Signed-off-by: Peter Rosin <peda@axentia.se>
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The Cherry Trail Whiskey Cove PMIC's IRQ line is attached to one of
the GPIOs of the Cherry Trail SoC. The CHT GPIO controller sometimes
fails to deliver IRQs (seen when there is an IRQ storm on another pin).
This commit works around this by reducing the long timeout which was
a poor attempt to workaround this from 3s to 30ms and after that
manually checking the status register for transfer completion by
calling the threaded IRQ handler directly.
This is safe todo as the entire threaded IRQ handler is protected
by a mutex.
Note 30ms should be more then long enough, at 100KHz any smbus single
byte transaction should be finished in 4ms.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Testing has shown that writing 1 to clear the read-complete irq does
not work until the data register has been read first.
This commit fixes the driver to read the data register first, halving the
amount of interrupts in most cases since we mostly read on this i2c bus.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Although unlikely without locking the smbux_xfer function may miss
the nack flag and further fixes in this patch-set add some more
complex constructions which need protection.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Fix smatch warning:
drivers/i2c/busses/i2c-sh_mobile.c:564 \
sh_mobile_i2c_request_dma_chan() warn: unused return: ret = PTR_ERR()
Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Fix smatch warning:
drivers/i2c/busses/i2c-rcar.c:628 \
rcar_i2c_request_dma_chan() warn: unused return: ret = PTR_ERR()
Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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I2C slave controller must be powered and active all the time when I2C
slave backend is registered in order to let master address and
communicate with us.
Now if the controller is runtime PM capable it will be suspended after
probe and cannot ever respond to the master or generate interrupts.
Fix this by resuming the controller when I2C slave backend is registered
and let it suspend after unregistering.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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I guess pm_runtime_put_noidle() call in i2c_dw_probe_slave() was copied
by accident from similar master mode adapter registration code. It is
unbalanced due missing pm_runtime_get_noresume() but harmless since it
doesn't decrease dev->power.usage_count below zero.
In theory we can hit similar needless runtime suspend/resume cycle
during slave mode adapter registration that was happening when
registering the master mode adapter. See commit cd998ded5c12 ("i2c:
designware: Prevent runtime suspend during adapter registration").
However, since we are slave, we can consider it as a wrong configuration
if we have other slaves attached under this adapter and can omit the
pm_runtime_get_noresume()/pm_runtime_put_noidle() calls for simplicity.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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serio_device_id are not supposed to change at runtime. All functions
working with serio_device_id provided by <linux/serio.h> work with
const serio_device_id. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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If i2c_mux_alloc() fails then we'd have a NULL dereference here.
Fixes: c4aee3e1b0de ("i2c: mux: pinctrl: remove platform_data")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
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Before I skipped null checks when the master is in the STOP state; this
fixes that.
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: f327c686d3ba ("i2c: aspeed: added driver for Aspeed I2C")
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24xx BMCs have larger clock divider granularity which can cause problems
when trying to set them as 25xx clock dividers; this adds clock setting
code specific to 24xx.
This also fixes a potential issue where clock dividers were rounded down
instead of up.
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Commit a53e35db70d1 ("reset: Ensure drivers are explicit when requesting
reset lines") started to transition the reset control request API calls
to explicitly state whether the driver needs exclusive or shared reset
control behavior. Convert all drivers requesting exclusive resets to the
explicit API call so the temporary transition helpers can be removed.
No functional changes.
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: linux-i2c@vger.kernel.org
Cc: linux-tegra@vger.kernel.org
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Commit a53e35db70d1 ("reset: Ensure drivers are explicit when requesting
reset lines") started to transition the reset control request API calls
to explicitly state whether the driver needs exclusive or shared reset
control behavior. Convert all drivers requesting exclusive resets to the
explicit API call so the temporary transition helpers can be removed.
No functional changes.
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: linux-i2c@vger.kernel.org
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Commit a53e35db70d1 ("reset: Ensure drivers are explicit when requesting
reset lines") started to transition the reset control request API calls
to explicitly state whether the driver needs exclusive or shared reset
control behavior. Convert all drivers requesting exclusive resets to the
explicit API call so the temporary transition helpers can be removed.
No functional changes.
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: linux-i2c@vger.kernel.org
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Commit a53e35db70d1 ("reset: Ensure drivers are explicit when requesting
reset lines") started to transition the reset control request API calls
to explicitly state whether the driver needs exclusive or shared reset
control behavior. Convert all drivers requesting exclusive resets to the
explicit API call so the temporary transition helpers can be removed.
No functional changes.
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-i2c@vger.kernel.org
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Use api pair of request_mem_region and release_mem_region
instead of release_resource.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Anton Vasilyev <vasilyev@ispras.ru>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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I2C drivers were required to have an I2C device ID table even if were for
devices that would only be registered using a specific firmware interface
(e.g: OF or ACPI).
But commit da10c06a044b ("i2c: Make I2C ID tables non-mandatory for DT'ed
devices") changed the I2C core to relax the requirement and allow drivers
to avoid defining this table.
Unfortunately it only took into account drivers for OF-only devices and
forgot about ACPI-only ones, and this was fixed by commit c64ffff7a9d1
("i2c: core: Allow empty id_table in ACPI case as well").
But the latter didn't update the original comment, so it doesn't reflect
what the code does now.
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Code sets bit DW_IC_CON_SPEED_FAST (0x4) always when configuring the slave
mode. This results incorrect register value DW_IC_CON_SPEED_HIGH (0x6)
when OR'ed together with DW_IC_CON_SPEED_STD (0x2).
Remove this and let the code set the speed mode bits according to clock
frequency or default to fast mode.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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When i2c-designware is initialized in slave mode the
i2c-designware-slave.c: i2c_dw_irq_handler_slave() can hit a NULL
pointer dereference when I2C slave backend is not registered but code is
accessing the struct dw_i2c_dev.slave without testing is it NULL.
We might get spurious interrupts from other devices or from IRQ core
during unloading the driver when CONFIG_DEBUG_SHIRQ is set. Existing
check for enable and IRQ status is not enough since device can be power
gated and those bits may read 1.
Fix this by handling the interrupt only when also struct dw_i2c_dev.slave
is set.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The commit 8503ff166504 ("i2c: designware: Avoid unnecessary resuming
during system suspend"), may suggest to the PM core to try out the so
called direct_complete path for system sleep. In this path, the PM core
treats a runtime suspended device as it's already in a proper low power
state for system sleep, which makes it skip calling the system sleep
callbacks for the device, except for the ->prepare() and the ->complete()
callbacks.
However, the PM core may unset the direct_complete flag for a parent
device, in case its child device are being system suspended before. In this
scenario, the PM core invokes the system sleep callbacks, no matter if the
device is runtime suspended or not.
Particularly in cases of an existing i2c slave device, the above path is
triggered, which breaks the assumption that the i2c device is always
runtime resumed whenever the dw_i2c_plat_suspend() is being called.
More precisely, dw_i2c_plat_suspend() calls clk_core_disable() and
clk_core_unprepare(), for an already disabled/unprepared clock, leading to
a splat in the log about clocks calls being wrongly balanced and breaking
system sleep.
To still allow the direct_complete path in cases when it's possible, but
also to keep the fix simple, let's runtime resume the i2c device in the
->suspend() callback, before continuing to put the device into low power
state.
Note, in cases when the i2c device is attached to the ACPI PM domain, this
problem doesn't occur, because ACPI's ->suspend() callback, assigned to
acpi_subsys_suspend(), already calls pm_runtime_resume() for the device.
It should also be noted that this change does not fix commit 8503ff166504
("i2c: designware: Avoid unnecessary resuming during system suspend").
Because for the non-ACPI case, the system sleep support was already broken
prior that point.
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: John Stultz <john.stultz@linaro.org>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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