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path: root/drivers/tty/serial/8250
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2023-06-21Revert "8250: add support for ASIX devices with a FIFO bug"Jiaqing Zhao
This reverts commit eb26dfe8aa7eeb5a5aa0b7574550125f8aa4c3b3. Commit eb26dfe8aa7e ("8250: add support for ASIX devices with a FIFO bug") merged on Jul 13, 2012 adds a quirk for PCI_VENDOR_ID_ASIX (0x9710). But that ID is the same as PCI_VENDOR_ID_NETMOS defined in 1f8b061050c7 ("[PATCH] Netmos parallel/serial/combo support") merged on Mar 28, 2005. In pci_serial_quirks array, the NetMos entry always takes precedence over the ASIX entry even since it was initially merged, code in that commit is always unreachable. In my tests, adding the FIFO workaround to pci_netmos_init() makes no difference, and the vendor driver also does not have such workaround. Given that the code was never used for over a decade, it's safe to revert it. Also, the real PCI_VENDOR_ID_ASIX should be 0x125b, which is used on their newer AX99100 PCIe serial controllers released on 2016. The FIFO workaround should not be intended for these newer controllers, and it was never implemented in vendor driver. Fixes: eb26dfe8aa7e ("8250: add support for ASIX devices with a FIFO bug") Cc: stable <stable@kernel.org> Signed-off-by: Jiaqing Zhao <jiaqing.zhao@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20230619155743.827859-1-jiaqing.zhao@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15serial: 8250_omap: Use force_suspend and resume for system suspendTony Lindgren
We should not rely on autosuspend timeout for system suspend. Instead, let's use force_suspend and force_resume functions. Otherwise the serial port controller device may not be idled on suspend. As we are doing a register write on suspend to configure the serial port, we still need to runtime PM resume the port on suspend. While at it, let's switch to pm_runtime_resume_and_get() and check for errors returned. And let's add the missing line break before return to the suspend function while at it. Fixes: 09d8b2bdbc5c ("serial: 8250: omap: Provide ability to enable/disable UART as wakeup source") Signed-off-by: Tony Lindgren <tony@atomide.com> Tested-by: Dhruva Gole <d-gole@ti.com> Message-ID: <20230614045922.4798-1-tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLEUwe Kleine-König
The need to handle the FSL variant of 8250 in a special way is also present without console support. So soften the dependency for SERIAL_8250_FSL from SERIAL_8250_CONSOLE to SERIAL_8250. To handle SERIAL_8250=m, the FSL code can be modular, too, thus SERIAL_8250_FSL becomes tristate. Compiling 8250_fsl as a module requires adding a module license so this is added, too. While add it also add a appropriate module description. As then SERIAL_OF_PLATFORM=y + SERIAL_8250_FSL=m is a valid combination (if COMPILE_TEST is enabled on a platform that is neither PPC, ARM nor ARM64), the check in 8250_of.c must be weakened a bit. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Message-ID: <20230609133932.786117-3-u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-06serial: 8250_mtk: Simplify clock sequencing and runtime PMChen-Yu Tsai
The 8250_mtk driver's runtime PM support has some issues: - The bus clock is enabled (through runtime PM callback) later than a register write - runtime PM resume callback directly called in probe, but no pm_runtime_set_active() call is present - UART PM function calls the callbacks directly, _and_ calls runtime PM API - runtime PM callbacks try to do reference counting, adding yet another count between runtime PM and clocks This fragile setup worked in a way, but broke recently with runtime PM support added to the serial core. The system would hang when the UART console was probed and brought up. Tony provided some potential fixes [1][2], though they were still a bit complicated. The 8250_dw driver, which the 8250_mtk driver might have been based on, has a similar structure but simpler runtime PM usage. Simplify clock sequencing and runtime PM support in the 8250_mtk driver. Specifically, the clock is acquired enabled and assumed to be active, unless toggled through runtime PM suspend/resume. Reference counting is removed and left to the runtime PM core. The serial pm function now only calls the runtime PM API. [1] https://lore.kernel.org/linux-serial/20230602092701.GP14287@atomide.com/ [2] https://lore.kernel.org/linux-serial/20230605061511.GW14287@atomide.com/ Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM") Suggested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Message-ID: <20230606091747.2031168-1-wenst@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-05Merge 6.4-rc5 into tty-nextGreg Kroah-Hartman
We need the tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-31serial: core: Start managing serial controllers to enable runtime PMTony Lindgren
We want to enable runtime PM for serial port device drivers in a generic way. To do this, we want to have the serial core layer manage the registered physical serial controller devices. To manage serial controllers, let's set up a struct bus and struct device for the serial core controller as suggested by Greg and Jiri. The serial core controller devices are children of the physical serial port device. The serial core controller device is needed to support multiple different kind of ports connected to single physical serial port device. Let's also set up a struct device for the serial core port. The serial core port instances are children of the serial core controller device. With the serial core port device we can now flush pending TX on the runtime PM resume as suggested by Johan. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Suggested-by: Jiri Slaby <jirislaby@kernel.org> Suggested-by: Johan Hovold <johan@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20230525113034.46880-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-31serial: 8250: omap: convert to modern PM opsArnd Bergmann
The new uart_write() function is only called from suspend/resume code, causing a build warning when those are left out: drivers/tty/serial/8250/8250_omap.c:169:13: error: 'uart_write' defined but not used [-Werror=unused-function] Remove the #ifdefs and use the modern pm_ops/pm_sleep_ops and their wrappers to let the compiler see where it's used but still drop the dead code. Fixes: 398cecc24846 ("serial: 8250: omap: Fix imprecise external abort for omap_8250_pm()") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230517202012.634386-1-arnd@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-31serial: 8250: omap: Move uart_write() inside PM sectionGeert Uytterhoeven
If CONFIG_PM is not set (e.g. m68k/allmodconfig): drivers/tty/serial/8250/8250_omap.c:169:13: error: ‘uart_write’ defined but not used [-Werror=unused-function] 169 | static void uart_write(struct omap8250_priv *priv, u32 reg, u32 val) | ^~~~~~~~~~ Fix tis by moving uart_write() inside the existing section protected by #ifdef CONFIG_PM. Reported-by: noreply@ellerman.id.au Link: http://kisskb.ellerman.id.au/kisskb/buildresult/14925095/ Fixes: 398cecc24846e867 ("serial: 8250: omap: Fix imprecise external abort for omap_8250_pm()") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230515065706.1723477-1-geert@linux-m68k.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-31serial: 8250-fsl: Expand description of the MPC83xx UART's misbehaviourUwe Kleine-König
After working quite a bit on erratic behaviour of the MPC83xx UART I (think I) understood the problem. Expand the description accoringly to conserve the knowledge for the future. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20230524122754.481816-2-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30serial: 8250_tegra: Fix an error handling path in tegra_uart_probe()Christophe JAILLET
If an error occurs after reset_control_deassert(), it must be re-asserted, as already done in the .remove() function. Fixes: c6825c6395b7 ("serial: 8250_tegra: Create Tegra specific 8250 driver") Cc: stable <stable@kernel.org> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Link: https://lore.kernel.org/r/f8130f35339cc80edc6b9aac4bb2a60b60a226bf.1684063511.git.christophe.jaillet@wanadoo.fr Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30serial: Indicate fintek option may also be required for RS232 supportJames Hilliard
The current config comment for SERIAL_8250_FINTEK implies that this option is only needed when one wants to support RS485. As it turns out we also need to enable this option for RS232 support to function correctly on some variants. For example for variants such as the F71869AD attempting to use multiple RS232 ports simultaneously without this option enabled can result in data corruption. Signed-off-by: James Hilliard <james.hilliard1@gmail.com> Link: https://lore.kernel.org/r/20230521075046.3539376-1-james.hilliard1@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30serial: 8250: synchronize and annotate UART_IER accessJohn Ogness
The UART_IER register is modified twice by each console write (serial8250_console_write()) under the port lock. Any driver code that accesses UART_IER must do so with the port locked in order to ensure consistent values, even when for read accesses. Add locking, lockdep notation, and/or comments everywhere UART_IER is accessed. The added locking is not fixing a real problem because it occurs where the console is not active. However, adding the locking to these non-critical paths greatly simplifies UART_IER access tracking by establishing a general policy that all UART_IER access is performed with the port locked. Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20230525093159.223817-9-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30serial: 8250: lock port for UART_IER access in omap8250_irq()John Ogness
omap8250_irq() accesses UART_IER. This register is modified twice by each console write (serial8250_console_write()) under the port lock. omap8250_irq() must also take the port lock to guanentee synchronized access to UART_IER. Since the port lock is already being taken for the stop_rx() callback and since it is safe to call cancel_delayed_work() while holding the port lock, simply extend the port lock region to include UART_IER access. Fixes: 1fe0e1fa3209 ("serial: 8250_omap: Handle optional overrun-throttle-ms property") Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230525093159.223817-8-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30serial: 8250: lock port for omap8250_restore_regs()John Ogness
omap8250_restore_regs() accesses UART_IER. This register is modified twice by each console write (serial8250_console_write()) under the port lock. However, not all calls to omap8250_restore_regs() are under the port lock. Add the missing port locking around omap8250_restore_regs() calls. Add lockdep notation to the omap8250_restore_regs(). Note that this is not fixing a real problem because the serial devices are resumed before console printing is enabled. However, adding this locking allows for clean locking semantics for omap8250_restore_regs() so that lockdep can be used to identify possible problems in the future. It also simplifies synchronization of UART_IER in general by not needing to rely on such implementation details. Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20230525093159.223817-7-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30serial: 8250: lock port for rx_dma() callbackJohn Ogness
The rx_dma() callback (omap_8250_rx_dma) accesses UART_IER. This register is modified twice by each console write (serial8250_console_write()) under the port lock. However, not all calls to the rx_dma() callback are under the port lock. Add the missing port locking around rx_dma() callback calls. Add lockdep notation to the omap_8250_rx_dma(). Note that this is not fixing a real problem because: 1. Currently DMA is forced off for 8250_omap consoles. 2. The serial devices are resumed before console printing is enabled. However, adding this locking allows for clean locking semantics for the rx_dma() callback so that lockdep can be used to identify possible problems in the future. It also simplifies synchronization of UART_IER in general by not needing to rely on implementation details such as 1 and 2. Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20230525093159.223817-6-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30serial: 8250: lock port for stop_rx() in omap8250_irq()John Ogness
The uarts_ops stop_rx() callback expects that the port->lock is taken and interrupts are disabled. Fixes: 1fe0e1fa3209 ("serial: 8250_omap: Handle optional overrun-throttle-ms property") Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230525093159.223817-4-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30serial: 8250: lock port in startup() callbacksJohn Ogness
uart_ops startup() callback is called without interrupts disabled and without port->lock locked, relatively late during the boot process (from the call path of console_on_rootfs()). If the device is a console, it was already previously registered and could be actively printing messages. The console printing function serial8250_console_write() modifies the interrupt register (UART_IER) under the port->lock with the pattern: read, clear, restore. Since some startup() callbacks are modifying UART_IER without the port->lock locked, it is possible that the value intended to be written by the startup() callback will get overwritten and be lost. CPU0 CPU1 serial8250_console_write omap_8250_startup -------------------------- ----------------- spin_lock(port->lock) oldval = read(UART_IER) uart_console_write() write(newval, UART_IER) write(oldval, UART_IER) spin_unlock(port->lock) Add port->lock synchronization to the 8250 startup() callbacks where they need to access UART_IER. This avoids racing with serial8250_console_write(). Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20230525093159.223817-2-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-27Merge 6.4-rc3 into tty-nextGreg Kroah-Hartman
We need the serial/tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250_bcm7271: fix leak in `brcmuart_probe`Doug Berger
Smatch reports: drivers/tty/serial/8250/8250_bcm7271.c:1120 brcmuart_probe() warn: 'baud_mux_clk' from clk_prepare_enable() not released on lines: 1032. The issue is fixed by using a managed clock. Fixes: 41a469482de2 ("serial: 8250: Add new 8250-core based Broadcom STB driver") Reported-by: XuDong Liu <m202071377@hust.edu.cn> Link: https://lore.kernel.org/lkml/20230424125100.4783-1-m202071377@hust.edu.cn/ Signed-off-by: Doug Berger <opendmb@gmail.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20230427181916.2983697-3-opendmb@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250_bcm7271: balance clk_enable callsDoug Berger
The sw_baud clock must be disabled when the device driver is not connected to the device. This now occurs when probe fails and upon remove. Fixes: 41a469482de2 ("serial: 8250: Add new 8250-core based Broadcom STB driver") Reported-by: XuDong Liu <m202071377@hust.edu.cn> Link: https://lore.kernel.org/lkml/20230424125100.4783-1-m202071377@hust.edu.cn/ Signed-off-by: Doug Berger <opendmb@gmail.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20230427181916.2983697-2-opendmb@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250: Document termios parameter of serial8250_em485_config()Geert Uytterhoeven
With W=1: drivers/tty/serial/8250/8250_port.c:679: warning: Function parameter or member 'termios' not described in 'serial8250_em485_config' Fix this by documenting the parameter. Fixes: ae50bb2752836277 ("serial: take termios_rwsem for ->rs485_config() & pass termios as param") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/2bd1e62be1d5d33333002910372feecc6d52e78f.1682071013.git.geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: Add support for Advantech PCI-1611U cardVitaliy Tomin
Add support for Advantech PCI-1611U card Advantech provides opensource drivers for this and many others card based on legacy copy of 8250_pci driver called adv950 https://www.advantech.com/emt/support/details/driver?id=1-TDOIMJ It is hard to maintain to run as out of tree module on newer kernels. Just adding PCI ID to kernel 8250_pci works perfect. Signed-off-by: Vitaliy Tomin <tomin@iszf.irk.ru> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/20230423034512.2671157-1-tomin@iszf.irk.ru Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250_exar: Add support for USR298x PCI ModemsAndrew Davis
Possibly the last PCI controller-based (i.e. not a soft/winmodem) dial-up modem one can still buy. Looks to have a stock XR17C154 PCI UART chip for communication, but for some reason when provisioning the PCI IDs they swapped the vendor and subvendor IDs. Otherwise this card would have worked out of the box. Searching online, some folks seem to not have this issue and others do, so it is possible only some batches of cards have this error. Create a new macro to handle the switched IDs and add support here. Signed-off-by: Andrew Davis <afd@ti.com> Cc: stable <stable@kernel.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20230420160209.28221-1-afd@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250_rt288x: Remove unnecessary UART_REG_UNMAPPEDIlpo Järvinen
As unmapped registers are at the tail of the array, the ARRAY_SIZE() condition will catch them just fine. No need to define special value for them. Convert the arrays to u8 as all entiries are now positive. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230511121029.13128-7-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250_rt288x: Name non-standard divisor latch regIlpo Järvinen
Instead of a literal, add proper name for the non-standard divisor latch register. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230511121029.13128-6-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250: RT288x/Au1xxx code away from coreIlpo Järvinen
A non-trivial amount of RT288x/Au1xxx code is encapsulated into ifdeffery in 8250_port / 8250_early and some if UPIO_AU blocks. Create a separate file from them. Also handle errors properly in the cases where RT288x/Au1xxx code is not configured. It seems that 0x1000 mapsize is likely overkill but I've kept it the same as previously (the value was shrunk to that value in commit b2b13cdfd05e ("SERIAL 8250: Fixes for Alchemy UARTs.")). Seemingly, the driver only needs to access register at 0x28 for the divisor latch. The Kconfig side is a bit tricky. As SERIAL_8250_RT288X is bool it can only be =y. It is possible to have SERIAL_8250=m + SERIAL_8250_RT288X=y which required altering when 8250/ is included or the rt288x would not be built. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230511121029.13128-5-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250: Add dl_read/write, bugs and mapsize into plat_serial8250_portIlpo Järvinen
Add mapsize, bugs, and divisor latch read/write functions (->dl_read/write()) into plat_serial8250_port to carry the setup necessary for RT288x/Au1xxx devices over to uart port. Document the added members with kerneldoc style but do not enable kerneldoc yet as there are many fields which remain undocumented. While at it, convert .bugs in struct uart_8250_port to u16 to match it with the type used in struct plat_serial8250_port. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230511121029.13128-4-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250: Change dl_read/write to handle value as u32Ilpo Järvinen
Divisor latch read/write functions currently handle the value is int. As the value is related to HW context, u32 makes much more sense than a signed type. While at it, name the parameters in the callback signature. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230511121029.13128-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250: Allow using ports higher than SERIAL_8250_RUNTIME_UARTSTony Lindgren
We already allocate CONFIG_SERIAL_8250_NR_UARTS, but only allow using CONFIG_SERIAL_8250_RUNTIME_UARTS uarts unless nr_uarts module params is set. This causes issues for using distro kernels on SoCs with a large number of serial ports. Let's allow up to CONFIG_SERIAL_8250_NR_UARTS instead. To do this, we init the ports as needed if the initial uarts was too low. This way there's no need to set the value for CONFIG_SERIAL_8250_RUNTIME_UARTS to some SoC specific higher value. Typically the default value of 4 can be used as set for legacy reasons. Note that limiting the number of intial uarts still works as before unless a serial console on a higher port is specified. In this case we will increase the nr_ports up to the console port specified. Suggested-by: Andrew Davis <afd@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230508111903.39339-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250: omap: Shut down on remove for console uartTony Lindgren
When unbinding the console uart, we want to power down the uart hardware on remove. For the console uart, the normal shutdown path will never get called as the cons_filp stays open. Let's rearrange the dma related functions a bit so we can call driver shutdown also on console uart rebind. Currently we set up->dma on probe, but that causes issues calling omap_8250_shutdown() on remove. The dma startup will not get called on the next rebind as we still have up->dma set from probe. Note that serial8250_release_dma() already checks for dma so we can remove the check for it in 8205_omap driver. With these changes we also avoid hogging dma virtual channels for the unused uarts that may be limited on some devices. Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230508082014.23083-5-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250: omap: Fix life cycle issues for interrupt handlersTony Lindgren
We have the struct uart_8250_port instance recycled on device rebind while the struct omap8250_priv instance is not. For the console uart, __tty_hangup() does not call tty->ops->hangup() as cons_filp stays open, and uart shutdown won't get called. This means we have a stale priv->wakeirq handler around after unbind, and port->irq is not freed on unbind. There's no need to claim the interrupts on startup. We can fix this and simplify the driver a bit by claiming the interrupts in probe, and clearing them on remove. For the device interrupt, we can use devm_request_irq(). To do this, we change omap8250_irq() to use struct omap8250_priv data directly so we don't have to wait for the assigned port from serial8250_register_8250_port(). We must also drop IRQF_SHARED to set IRQ_NOAUTOEN to avoid spurious interrupts until the port has been registered. There's no need for IRQF_SHARED for 8250_omap, the serial port interrupt lines are dedicated lines. Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230508082014.23083-4-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250: omap: Fix imprecise external abort for omap_8250_pm()Tony Lindgren
We must idle the uart only after serial8250_unregister_port(). Otherwise unbinding the uart via sysfs while doing cat on the port produces an imprecise external abort: mem_serial_in from omap_8250_pm+0x44/0xf4 omap_8250_pm from uart_hangup+0xe0/0x194 uart_hangup from __tty_hangup.part.0+0x37c/0x3a8 __tty_hangup.part.0 from uart_remove_one_port+0x9c/0x22c uart_remove_one_port from serial8250_unregister_port+0x60/0xe8 serial8250_unregister_port from omap8250_remove+0x6c/0xd0 omap8250_remove from platform_remove+0x28/0x54 Turns out the driver needs to have runtime PM functional before the driver probe calls serial8250_register_8250_port(). And it needs runtime PM after driver remove calls serial8250_unregister_port(). On probe, we need to read registers before registering the port in omap_serial_fill_features_erratas(). We do that with custom uart_read() already. On remove, after serial8250_unregister_port(), we need to write to the uart registers to idle the device. Let's add a custom uart_write() for that. Currently the uart register access depends on port->membase to be initialized, which won't work after serial8250_unregister_port(). Let's use priv->membase instead, and use it for runtime PM related functions to remove the dependency to port->membase for early and late register access. Note that during use, we need to check for a valid port in the runtime PM related functions. This is needed for the optional wakeup configuration. We now need to set the drvdata a bit earlier so it's available for the runtime PM functions. With the port checks in runtime PM functions, the old checks for priv in omap8250_runtime_suspend() and omap8250_runtime_resume() functions are no longer needed and are removed. Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230508082014.23083-3-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: 8250: omap: Fix freeing of resources on failed registerTony Lindgren
If serial8250_register_8250_port() fails, the SoC can hang as the deferred PMQoS work will still run as is not flushed and removed. Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver") Signed-off-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230508082014.23083-2-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-27Merge tag 'tty-6.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty / serial updates from Greg KH: "Here is the big set of tty/serial driver updates for 6.4-rc1. Nothing major, just lots of tiny, constant, forward development. This includes: - obligatory n_gsm updates and feature additions - 8250_em driver updates - sh-sci driver updates - dts cleanups and updates - general cleanups and improvements by Ilpo and Jiri - other small serial driver core fixes and driver updates All of these have been in linux-next for a while with no reported problems" * tag 'tty-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (87 commits) n_gsm: Use array_index_nospec() with index that comes from userspace tty: vt: drop checks for undefined VT_SINGLE_DRIVER tty: vt: distribute EXPORT_SYMBOL() tty: vt: simplify some cases in tioclinux() tty: vt: reformat tioclinux() tty: serial: sh-sci: Fix end of transmission on SCI tty: serial: sh-sci: Add support for tx end interrupt handling tty: serial: sh-sci: Fix TE setting on SCI IP tty: serial: sh-sci: Add RZ/G2L SCIFA DMA rx support tty: serial: sh-sci: Add RZ/G2L SCIFA DMA tx support serial: max310x: fix IO data corruption in batched operations serial: core: Disable uart_start() on uart_remove_one_port() serial: 8250: Reinit port->pm on port specific driver unbind serial: 8250: Add missing wakeup event reporting tty: serial: fsl_lpuart: use UARTMODIR register bits for lpuart32 platform tty: serial: fsl_lpuart: adjust buffer length to the intended size serial: fix TIOCSRS485 locking serial: make SiFive serial drivers depend on ARCH_ symbols tty: synclink_gt: don't allocate and pass dummy flags tty: serial: simplify qcom_geni_serial_send_chunk_fifo() ...
2023-04-24Merge branches 'acpi-bus', 'acpi-video' and 'acpi-misc'Rafael J. Wysocki
Merge ACPI bus type driver changes, ACPI backlight driver updates and a series of cleanups related to of.h for 6.4-rc1: - Ensure that ACPI notify handlers are not running after removal and clean up code in acpi_sb_notify() (Rafael Wysocki). - Remove register_backlight_delay module option and code and remove quirks for false-positive backlight control support advertised on desktop boards (Hans de Goede). - Replace irqdomain.h include with struct declarations in ACPI headers and update several pieces of code previously including of.h implicitly through those headers (Rob Herring). * acpi-bus: ACPI: bus: Ensure that notify handlers are not running after removal ACPI: bus: Add missing braces to acpi_sb_notify() * acpi-video: ACPI: video: Remove desktops without backlight DMI quirks ACPI: video: Remove register_backlight_delay module option and code * acpi-misc: ACPI: Replace irqdomain.h include with struct declarations fpga: lattice-sysconfig-spi: Add explicit include for of.h tpm: atmel: Add explicit include for of.h virtio-mmio: Add explicit include for of.h pata: ixp4xx: Add explicit include for of.h ata: pata_macio: Add explicit include of irqdomain.h serial: 8250_tegra: Add explicit include for of.h net: rfkill-gpio: Add explicit include for of.h staging: iio: resolver: ad2s1210: Add explicit include for of.h iio: adc: ad7292: Add explicit include for of.h
2023-04-20serial: 8250: Reinit port->pm on port specific driver unbindTony Lindgren
When we unbind a serial port hardware specific 8250 driver, the generic serial8250 driver takes over the port. After that we see an oops about 10 seconds later. This can produce the following at least on some TI SoCs: Unhandled fault: imprecise external abort (0x1406) Internal error: : 1406 [#1] SMP ARM Turns out that we may still have the serial port hardware specific driver port->pm in use, and serial8250_pm() tries to call it after the port specific driver is gone: serial8250_pm [8250_base] from uart_change_pm+0x54/0x8c [serial_base] uart_change_pm [serial_base] from uart_hangup+0x154/0x198 [serial_base] uart_hangup [serial_base] from __tty_hangup.part.0+0x328/0x37c __tty_hangup.part.0 from disassociate_ctty+0x154/0x20c disassociate_ctty from do_exit+0x744/0xaac do_exit from do_group_exit+0x40/0x8c do_group_exit from __wake_up_parent+0x0/0x1c Let's fix the issue by calling serial8250_set_defaults() in serial8250_unregister_port(). This will set the port back to using the serial8250 default functions, and sets the port->pm to point to serial8250_pm. Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230418101407.12403-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20serial: 8250: Add missing wakeup event reportingFlorian Fainelli
An 8250 UART configured as a wake-up source would not have reported itself through sysfs as being the source of wake-up, correct that. Fixes: b3b708fa2780 ("wake up from a serial port") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20230414170241.2016255-1-f.fainelli@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-10Merge 6.3-rc6 into tty-nextGreg Kroah-Hartman
We need the tty/serial fixes in here for testing. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-06serial: 8250_tegra: Add explicit include for of.hRob Herring
With linux/acpi.h no longer implicitly including of.h, add an explicit include of of.h to fix the following error: drivers/tty/serial/8250/8250_tegra.c:68:15: error: implicit declaration of function 'of_alias_get_id' [-Werror=implicit-function-declaration] Reviewed-by: Jon Hunter <jonathanh@nvidia.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-03-29serial: 8250: Prevent starting up DMA Rx on THRI interruptIlpo Järvinen
Hans de Goede reported Bluetooth adapters (HCIs) connected over an UART connection failed due corrupted Rx payload. The problem was narrowed down to DMA Rx starting on UART_IIR_THRI interrupt. The problem occurs despite LSR having DR bit set, which is precondition for attempting to start DMA Rx in the first place. From a debug patch: [x.807834] 8250irq: iir=cc lsr+saved=60 received=0/15 ier=0f dma_t/rx/err=0/0/0 [x.808676] 8250irq: iir=c2 lsr+saved=61 received=0/0 ier=0f dma_t/rx/err=0/0/0 [x.808776] 8250irq: iir=cc lsr+saved=60 received=1/12 ier=0d dma_t/rx/err=0/1/0 [x.808870] Bluetooth: hci0: Frame reassembly failed (-84) In the debug snippet, received field indicates 1 byte was transferred over DMA and 12 bytes after that with the non-DMA Rx. The sole byte DMA handled was corrupted (gets zeroed) which leads to the HCI failure. This problem became apparent after commit e8ffbb71f783 ("serial: 8250: use THRE & __stop_tx also with DMA") changed Tx stop behavior. Tx stop is now triggered from a THRI interrupt. Despite that this problem looks like a HW bug, this fix is not adding UART_BUG_xx flag to the driver beucase it seems useful in general to avoid starting DMA when there are only a few bytes to transfer. Skipping DMA for small transfers avoids the extra overhead DMA incurs. Thus, don't setup DMA Rx on UART_IIR_THRI but leave it to a subsequent interrupt which has Rx a related IIR value. By returning false from handle_rx_dma(), the DMA vs non-DMA decision is postponed until either UART_IIR_RDI (FIFO threshold worth of bytes awaiting) or UART_IIR_TIMEOUT (inter-character timeout) triggers at a later time which allows better to discern whether the number of bytes warrants starting DMA or not. Reported-by: Hans de Goede <hdegoede@redhat.com> Tested-by: Hans de Goede <hdegoede@redhat.com> Fixes: e8ffbb71f783 ("serial: 8250: use THRE & __stop_tx also with DMA") Cc: stable@vger.kernel.org Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20230317103034.12881-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-29serial: 8250: Fix serial8250_tx_empty() race with DMA TxIlpo Järvinen
There's a potential race before THRE/TEMT deasserts when DMA Tx is starting up (or the next batch of continuous Tx is being submitted). This can lead to misdetecting Tx empty condition. It is entirely normal for THRE/TEMT to be set for some time after the DMA Tx had been setup in serial8250_tx_dma(). As Tx side is definitely not empty at that point, it seems incorrect for serial8250_tx_empty() claim Tx is empty. Fix the race by also checking in serial8250_tx_empty() whether there's DMA Tx active. Note: This fix only addresses in-kernel race mainly to make using TCSADRAIN/FLUSH robust. Userspace can still cause other races but they seem userspace concurrency control problems. Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine") Cc: stable@vger.kernel.org Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230317113318.31327-3-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-20Merge 6.3-rc3 into tty-nextGreg Kroah-Hartman
We need the tty/serial fixes in here and it resolves a merge conflict with: drivers/tty/serial/8250/8250_em.c Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17serial: 8250_bcm7271: Fix arbitration handlingDoug Berger
The arbitration of the UART DMA is mishandled for a few exceptional cases when probing and releasing the driver. It is possible that the DMA register spaces are not defined in device tree for an instance of the driver, so attempts to access the registers in brcmuart_arbitration() would use NULL pointers. It is also possible for the probe function to return an error while still holding the UART DMA. This would prevent the UART DMA from being claimed by an instance that could use it. These errors are addressed by only releasing the UART DMA if it is held by this instance (i.e. priv->dma_enabled == 1) and directing early error paths in probe to this common release_dma handling. Fixes: 41a469482de2 ("serial: 8250: Add new 8250-core based Broadcom STB driver") Signed-off-by: Doug Berger <opendmb@gmail.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20230309190224.687380-1-opendmb@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09serial: 8250_em: Add serial8250_em_{reg_update(),out_helper()}Biju Das
As per RZ/V2M hardware manual(Rev.1.30 Jun, 2022), UART IP has a restriction as mentioned below. 40.6.1 Point for Caution when Changing the Register Settings: When changing the settings of the following registers, a PRESETn master reset or FIFO reset + SW reset (FCR[2],FCR[1], HCR0[7]) must be input to re-initialize them. Target Registers: FCR, LCR, MCR, DLL, DLM, HCR0. Add serial8250_em_reg_update() and serial8250_em_serial_out_helper() to handle this restriction. serial8250_em_serial_out_helper() is identical to previous serial8250_em_serial_out() except that UART_FCR macro is removed from serial8250_em_serial_out_helper() as it is now handled by serial8250_ em_serial_out(). DLL/DLM register can be updated only by setting LCR[7]. So the updation of LCR[7] will perform reset for DLL/DLM register changes. EMMA mobile has the same register set as RZ/V2M and this patch is tested on EMEV2 board. So, there is no harm in applying the same restriction here as well as the HW manual for EMMA mobile is not updated for a long time. Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230227114152.22265-8-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09serial: 8250_em: Use pseudo offset for UART_FCRBiju Das
UART_FCR shares the same offset with UART_IIR. We cannot use UART_FCR in serial8250_em_serial_in() as it overlaps with UART_IIR. Define UART_FCR_EM macro with a high value to avoid overlapping with existing UART_* register defines and define another macro UART_FCR_EM_HW for the real offset. Use these macros in serial8250_em_serial{_in/_out} function to read/write FCR register. Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230227114152.22265-7-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09serial: 8250_em: Use devm_clk_get_enabled()Biju Das
Simplify clk handling in probe() by replacing devm_clk_get()->devm_ clk_get_enabled(). This replaces the usage of clk_prepare_enable/clk_ disable_unprepare() in probe()/remove(). After that sclk is no longer required in struct serial8250_em_priv and is replaced by a local variable sclk in probe(). Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230227114152.22265-6-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09serial: 8250_em: Add missing break statementBiju Das
Add missing break statement in serial8250_em_serial_out(). Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230227114152.22265-5-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09serial: 8250_em: Drop unused header fileBiju Das
Drop unused header file slab.h from the driver. Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230227114152.22265-4-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09serial: 8250_em: Simplify probe()Biju Das
Simplify probe() by using dev_err_probe() instead of dev_err() and add a local variable 'dev' to replace '&pdev->dev'. Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230227114152.22265-3-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09serial: 8250_em: Fix UART port typeBiju Das
As per HW manual for EMEV2 "R19UH0040EJ0400 Rev.4.00", the UART IP found on EMMA mobile SoC is Register-compatible with the general-purpose 16750 UART chip. Fix UART port type as 16750 and enable 64-bytes fifo support. Fixes: 22886ee96895 ("serial8250-em: Emma Mobile UART driver V2") Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230227114152.22265-2-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>