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Commit d49216438139
("serial: sc16is7xx: split into core and I2C/SPI parts (core)")
removed Kconfig SPI_MASTER or I2C dependency for SERIAL_SC16IS7XX (core).
This removal was done because I inadvertently misinterpreted some review
comments.
Because of that, the driver question now pops up if both I2C and
SPI_MASTER are disabled.
Re-add Kconfig SPI_MASTER or I2C dependency to fix the problem.
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: d49216438139 ("serial: sc16is7xx: split into core and I2C/SPI parts (core)")
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20240603152601.3689319-3-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit d49216438139
("serial: sc16is7xx: split into core and I2C/SPI parts (core)")
renamed SERIAL_SC16IS7XX_CORE by SERIAL_SC16IS7XX. This means that some
configs should have been updated when I submitted the original patch, but
unfortunately they were not. Geert mentioned for example:
arch/mips/configs/cu1??0-neo_defconfig
Rename SERIAL_SC16IS7XX to SERIAL_SC16IS7XX_CORE so that existing configs
will still work correctly.
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: d49216438139 ("serial: sc16is7xx: split into core and I2C/SPI parts (core)")
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20240603152601.3689319-2-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Recently, suspend testing on sc7180-trogdor based devices has started
to sometimes fail with messages like this:
port a88000.serial:0.0: PM: calling pm_runtime_force_suspend+0x0/0xf8 @ 28934, parent: a88000.serial:0
port a88000.serial:0.0: PM: dpm_run_callback(): pm_runtime_force_suspend+0x0/0xf8 returns -16
port a88000.serial:0.0: PM: pm_runtime_force_suspend+0x0/0xf8 returned -16 after 33 usecs
port a88000.serial:0.0: PM: failed to suspend: error -16
I could reproduce these problems by logging in via an agetty on the
debug serial port (which was _not_ used for kernel console) and
running:
cat /var/log/messages
...and then (via an SSH session) forcing a few suspend/resume cycles.
Tracing through the code and doing some printf()-based debugging shows
that the -16 (-EBUSY) comes from the recently added
serial_port_runtime_suspend().
The idea of the serial_port_runtime_suspend() function is to prevent
the port from being _runtime_ suspended if it still has bytes left to
transmit. Having bytes left to transmit isn't a reason to block
_system_ suspend, though. If a serdev device in the kernel needs to
block system suspend it should block its own suspend and it can use
serdev_device_wait_until_sent() to ensure bytes are sent.
The DEFINE_RUNTIME_DEV_PM_OPS() used by the serial_port code means
that the system suspend function will be pm_runtime_force_suspend().
In pm_runtime_force_suspend() we can see that before calling the
runtime suspend function we'll call pm_runtime_disable(). This should
be a reliable way to detect that we're called from system suspend and
that we shouldn't look for busyness.
Fixes: 43066e32227e ("serial: port: Don't suspend if the port is still busy")
Cc: stable@vger.kernel.org
Reviewed-by: Tony Lindgren <tony.lindgren@linux.intel.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20240531080914.v3.1.I2395e66cf70c6e67d774c56943825c289b9c13e4@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The FIFO is 64 bytes, but the FCR is configured to fire the TX interrupt
when the FIFO is half empty (bit 3 = 0). Thus, we should only write 32
bytes when a TX interrupt occurs.
This fixes a problem observed on the PXA168 that dropped a bunch of TX
bytes during large transmissions.
Fixes: ab28f51c77cd ("serial: rewrite pxa2xx-uart to use 8250_core")
Signed-off-by: Doug Brown <doug@schmorgal.com>
Link: https://lore.kernel.org/r/20240519191929.122202-1-doug@schmorgal.com
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit d9666dfb314e1ffd6eb9c3c4243fe3e094c047a7.
The container of the struct dw8250_port_data is private to the actual
driver. In particular, 8250_lpss and 8250_dw use different data types
that are assigned to the UART port private_data. Hence, it must not
be used outside the specific driver.
Fix the mistake made in the past by moving the respective definitions
to the specific driver.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240514190730.2787071-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The container of the struct dw8250_port_data is private to the actual
driver. In particular, 8250_lpss and 8250_dw use different data types
that are assigned to the UART port private_data. Hence, it must not
be used outside the specific driver.
Currently the only cpr_val is required by the common code, make it
be available via struct dw8250_port_data.
This fixes the UART breakage on Intel Galileo boards.
Fixes: 593dea000bc1 ("serial: 8250: dw: Allow to use a fallback CPR value if not synthesized")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240514190730.2787071-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When lookahead has "consumed" some characters (la_count > 0),
n_tty_receive_buf_standard() and n_tty_receive_buf_closing() for
characters beyond the la_count are given wrong cp/fp offsets which
leads to duplicating and losing some characters.
If la_count > 0, correct buffer pointers and make count consistent too
(the latter is not strictly necessary to fix the issue but seems more
logical to adjust all variables immediately to keep state consistent).
Reported-by: Vadym Krevs <vkrevs@yahoo.com>
Fixes: 6bb6fa6908eb ("tty: Implement lookahead to process XON/XOFF timely")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218834
Tested-by: Vadym Krevs <vkrevs@yahoo.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240514140429.12087-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull ata fixes from Niklas Cassel:
- Add a quirk for three different devices that have shown issues with
LPM (link power management). These devices appear to not implement
LPM properly, since we see command timeouts when enabling LPM. The
quirk disables LPM for these problematic devices. (Me)
- Do not apply the Intel PCS quirk on Alder Lake. The quirk is not
needed and was originally added by mistake when LPM support was
enabled for this AHCI controller. Enabling the quirk when not needed
causes the the controller to not be able to detect the connected
devices on some platforms.
* tag 'ata-6.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux:
ata: libata-core: Add ATA_HORKAGE_NOLPM for Apacer AS340
ata: libata-core: Add ATA_HORKAGE_NOLPM for AMD Radeon S3 SSD
ata: libata-core: Add ATA_HORKAGE_NOLPM for Crucial CT240BX500SSD1
ata: ahci: Do not apply Intel PCS quirk on Intel Alder Lake
Pull x86 fixes from Ingo Molnar:
"Miscellaneous topology parsing fixes:
- Fix topology parsing regression on older CPUs in the new AMD/Hygon
parser
- Fix boot crash on odd Intel Quark and similar CPUs that do not fill
out cpuinfo_x86::x86_clflush_size and zero out
cpuinfo_x86::x86_cache_alignment as a result.
Provide 32 bytes as a general fallback value.
- Fix topology enumeration on certain rare CPUs where the BIOS locks
certain CPUID leaves and the kernel unlocked them late, which broke
with the new topology parsing code. Factor out this unlocking logic
and move it earlier in the parsing sequence"
* tag 'x86-urgent-2024-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/topology/intel: Unlock CPUID before evaluating anything
x86/cpu: Provide default cache line size if not enumerated
x86/topology/amd: Evaluate SMT in CPUID leaf 0x8000001e only on family 0x17 and greater
Commit 7627a0edef54 ("ata: ahci: Drop low power policy board type")
dropped the board_ahci_low_power board type, and instead enables LPM if:
-The AHCI controller reports that it supports LPM (Partial/Slumber), and
-CONFIG_SATA_MOBILE_LPM_POLICY != 0, and
-The port is not defined as external in the per port PxCMD register, and
-The port is not defined as hotplug capable in the per port PxCMD
register.
Partial and Slumber LPM states can either be initiated by HIPM or DIPM.
For HIPM (host initiated power management) to get enabled, both the AHCI
controller and the drive have to report that they support HIPM.
For DIPM (device initiated power management) to get enabled, only the
drive has to report that it supports DIPM. However, the HBA will reject
device requests to enter LPM states which the HBA does not support.
The problem is that Apacer AS340 drives do not handle low power modes
correctly. The problem was most likely not seen before because no one
had used this drive with a AHCI controller with LPM enabled.
Add a quirk so that we do not enable LPM for this drive, since we see
command timeouts if we do (even though the drive claims to support DIPM).
Fixes: 7627a0edef54 ("ata: ahci: Drop low power policy board type")
Cc: stable@vger.kernel.org
Reported-by: Tim Teichmann <teichmanntim@outlook.de>
Closes: https://lore.kernel.org/linux-ide/87bk4pbve8.ffs@tglx/
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Pull scheduler fix from Ingo Molnar:
"Export a symbol to make life easier for instrumentation/debugging"
* tag 'sched-urgent-2024-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/x86: Export 'percpu arch_freq_scale'
Intel CPUs have a MSR bit to limit CPUID enumeration to leaf two. If
this bit is set by the BIOS then CPUID evaluation including topology
enumeration does not work correctly as the evaluation code does not try
to analyze any leaf greater than two.
This went unnoticed before because the original topology code just
repeated evaluation several times and managed to overwrite the initial
limited information with the correct one later. The new evaluation code
does it once and therefore ends up with the limited and wrong
information.
Cure this by unlocking CPUID right before evaluating anything which
depends on the maximum CPUID leaf being greater than two instead of
rereading stuff after unlock.
Fixes: 22d63660c35e ("x86/cpu: Use common topology code for Intel")
Reported-by: Peter Schneider <pschneider1968@googlemail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Peter Schneider <pschneider1968@googlemail.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/fd3f73dc-a86f-4bcf-9c60-43556a21eb42@googlemail.com
Commit 7627a0edef54 ("ata: ahci: Drop low power policy board type")
dropped the board_ahci_low_power board type, and instead enables LPM if:
-The AHCI controller reports that it supports LPM (Partial/Slumber), and
-CONFIG_SATA_MOBILE_LPM_POLICY != 0, and
-The port is not defined as external in the per port PxCMD register, and
-The port is not defined as hotplug capable in the per port PxCMD
register.
Partial and Slumber LPM states can either be initiated by HIPM or DIPM.
For HIPM (host initiated power management) to get enabled, both the AHCI
controller and the drive have to report that they support HIPM.
For DIPM (device initiated power management) to get enabled, only the
drive has to report that it supports DIPM. However, the HBA will reject
device requests to enter LPM states which the HBA does not support.
The problem is that AMD Radeon S3 SSD drives do not handle low power modes
correctly. The problem was most likely not seen before because no one
had used this drive with a AHCI controller with LPM enabled.
Add a quirk so that we do not enable LPM for this drive, since we see
command timeouts if we do (even though the drive claims to support both
HIPM and DIPM).
Fixes: 7627a0edef54 ("ata: ahci: Drop low power policy board type")
Cc: stable@vger.kernel.org
Reported-by: Doru Iorgulescu <doru.iorgulescu1@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218832
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Pull perf events fix from Ingo Molnar:
"Add missing MODULE_DESCRIPTION() lines"
* tag 'perf-urgent-2024-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Add missing MODULE_DESCRIPTION() lines
perf/x86/rapl: Add missing MODULE_DESCRIPTION() line
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