linux-stable.git/drivers/tty/serial, branch v5.4.78 Linux kernel stable tree tty: serial: fsl_lpuart: LS1021A has a FIFO size of 16 words, like LS1028A 2020-11-10T11:37:33+00:00 Vladimir Oltean vladimir.oltean@nxp.com 2020-10-23T01:34:29+00:00 86875e1d6426ac1308c969abd1eb0eaf24ab40b4 commit c97f2a6fb3dfbfbbc88edc8ea62ef2b944e18849 upstream. Prior to the commit that this one fixes, the FIFO size was derived from the read-only register LPUARTx_FIFO[TXFIFOSIZE] using the following formula: TX FIFO size = 2 ^ (LPUARTx_FIFO[TXFIFOSIZE] - 1) The documentation for LS1021A is a mess. Under chapter 26.1.3 LS1021A LPUART module special consideration, it mentions TXFIFO_SZ and RXFIFO_SZ being equal to 4, and in the register description for LPUARTx_FIFO, it shows the out-of-reset value of TXFIFOSIZE and RXFIFOSIZE fields as "011", even though these registers read as "101" in reality. And when LPUART on LS1021A was working, the "101" value did correspond to "16 datawords", by applying the formula above, even though the documentation is wrong again (!!!!) and says that "101" means 64 datawords (hint: it doesn't). So the "new" formula created by commit f77ebb241ce0 has all the premises of being wrong for LS1021A, because it relied only on false data and no actual experimentation. Interestingly, in commit c2f448cff22a ("tty: serial: fsl_lpuart: add LS1028A support"), Michael Walle applied a workaround to this by manually setting the FIFO widths for LS1028A. It looks like the same values are used by LS1021A as well, in fact. When the driver thinks that it has a deeper FIFO than it really has, getty (user space) output gets truncated. Many thanks to Michael for pointing out where to look. Fixes: f77ebb241ce0 ("tty: serial: fsl_lpuart: correct the FIFO depth size") Suggested-by: Michael Walle <michael@walle.cc> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://lore.kernel.org/r/20201023013429.3551026-1-vladimir.oltean@nxp.com Reviewed-by：Fugang Duan <fugang.duan@nxp.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c97f2a6fb3dfbfbbc88edc8ea62ef2b944e18849 upstream.

Prior to the commit that this one fixes, the FIFO size was derived from
the read-only register LPUARTx_FIFO[TXFIFOSIZE] using the following
formula:

TX FIFO size = 2 ^ (LPUARTx_FIFO[TXFIFOSIZE] - 1)

The documentation for LS1021A is a mess. Under chapter 26.1.3 LS1021A
LPUART module special consideration, it mentions TXFIFO_SZ and RXFIFO_SZ
being equal to 4, and in the register description for LPUARTx_FIFO, it
shows the out-of-reset value of TXFIFOSIZE and RXFIFOSIZE fields as "011",
even though these registers read as "101" in reality.

And when LPUART on LS1021A was working, the "101" value did correspond
to "16 datawords", by applying the formula above, even though the
documentation is wrong again (!!!!) and says that "101" means 64 datawords
(hint: it doesn't).

So the "new" formula created by commit f77ebb241ce0 has all the premises
of being wrong for LS1021A, because it relied only on false data and no
actual experimentation.

Interestingly, in commit c2f448cff22a ("tty: serial: fsl_lpuart: add
LS1028A support"), Michael Walle applied a workaround to this by manually
setting the FIFO widths for LS1028A. It looks like the same values are
used by LS1021A as well, in fact.

When the driver thinks that it has a deeper FIFO than it really has,
getty (user space) output gets truncated.

Many thanks to Michael for pointing out where to look.

Fixes: f77ebb241ce0 ("tty: serial: fsl_lpuart: correct the FIFO depth size")
Suggested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20201023013429.3551026-1-vladimir.oltean@nxp.com
Reviewed-by：Fugang Duan <fugang.duan@nxp.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: fsl_lpuart: add LS1028A support 2020-11-10T11:37:33+00:00 Michael Walle michael@walle.cc 2020-03-06T21:44:32+00:00 8febdfb5973db600c998b5e65d7cdf3cd250de39 commit c2f448cff22a7ed09281f02bde084b0ce3bc61ed upstream. The LS1028A uses little endian register access and has a different FIFO size encoding. Signed-off-by: Michael Walle <michael@walle.cc> Link: https://lore.kernel.org/r/20200306214433.23215-4-michael@walle.cc Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c2f448cff22a7ed09281f02bde084b0ce3bc61ed upstream.

The LS1028A uses little endian register access and has a different FIFO
size encoding.

Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200306214433.23215-4-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: txx9: add missing platform_driver_unregister() on error in serial_txx9_init 2020-11-10T11:37:32+00:00 Qinglang Miao miaoqinglang@huawei.com 2020-11-03T08:49:42+00:00 62c4b2b21e3b6dcfc3659c8c22027a8888dd0814 commit 0c5fc92622ed5531ff324b20f014e9e3092f0187 upstream. Add the missing platform_driver_unregister() before return from serial_txx9_init in the error handling case when failed to register serial_txx9_pci_driver with macro ENABLE_SERIAL_TXX9_PCI defined. Fixes: ab4382d27412 ("tty: move drivers/serial/ to drivers/tty/serial/") Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com> Link: https://lore.kernel.org/r/20201103084942.109076-1-miaoqinglang@huawei.com Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0c5fc92622ed5531ff324b20f014e9e3092f0187 upstream.

Add the missing platform_driver_unregister() before return
from serial_txx9_init in the error handling case when failed
to register serial_txx9_pci_driver with macro ENABLE_SERIAL_TXX9_PCI
defined.

Fixes: ab4382d27412 ("tty: move drivers/serial/ to drivers/tty/serial/")
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Link: https://lore.kernel.org/r/20201103084942.109076-1-miaoqinglang@huawei.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: 8250_mtk: Fix uart_get_baud_rate warning 2020-11-10T11:37:32+00:00 Claire Chang tientzu@chromium.org 2020-11-02T12:07:49+00:00 085fc4784e4bf7799eb23a6ed202d14fb5b75029 commit 912ab37c798770f21b182d656937072b58553378 upstream. Mediatek 8250 port supports speed higher than uartclk / 16. If the baud rates in both the new and the old termios setting are higher than uartclk / 16, the WARN_ON in uart_get_baud_rate() will be triggered. Passing NULL as the old termios so uart_get_baud_rate() will use uartclk / 16 - 1 as the new baud rate which will be replaced by the original baud rate later by tty_termios_encode_baud_rate() in mtk8250_set_termios(). Fixes: 551e553f0d4a ("serial: 8250_mtk: Fix high-speed baud rates clamping") Signed-off-by: Claire Chang <tientzu@chromium.org> Link: https://lore.kernel.org/r/20201102120749.374458-1-tientzu@chromium.org Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 912ab37c798770f21b182d656937072b58553378 upstream.

Mediatek 8250 port supports speed higher than uartclk / 16. If the baud
rates in both the new and the old termios setting are higher than
uartclk / 16, the WARN_ON in uart_get_baud_rate() will be triggered.
Passing NULL as the old termios so uart_get_baud_rate() will use
uartclk / 16 - 1 as the new baud rate which will be replaced by the
original baud rate later by tty_termios_encode_baud_rate() in
mtk8250_set_termios().

Fixes: 551e553f0d4a ("serial: 8250_mtk: Fix high-speed baud rates clamping")
Signed-off-by: Claire Chang <tientzu@chromium.org>
Link: https://lore.kernel.org/r/20201102120749.374458-1-tientzu@chromium.org
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: pl011: Fix lockdep splat when handling magic-sysrq interrupt 2020-11-01T11:01:06+00:00 Peter Zijlstra peterz@infradead.org 2020-09-30T12:04:32+00:00 870d910e1afb196fa7558e6de41ea749e7605638 commit 534cf755d9df99e214ddbe26b91cd4d81d2603e2 upstream. Issuing a magic-sysrq via the PL011 causes the following lockdep splat, which is easily reproducible under QEMU: | sysrq: Changing Loglevel | sysrq: Loglevel set to 9 | | ====================================================== | WARNING: possible circular locking dependency detected | 5.9.0-rc7 #1 Not tainted | ------------------------------------------------------ | systemd-journal/138 is trying to acquire lock: | ffffab133ad950c0 (console_owner){-.-.}-{0:0}, at: console_lock_spinning_enable+0x34/0x70 | | but task is already holding lock: | ffff0001fd47b098 (&port_lock_key){-.-.}-{2:2}, at: pl011_int+0x40/0x488 | | which lock already depends on the new lock. [...] | Possible unsafe locking scenario: | | CPU0 CPU1 | ---- ---- | lock(&port_lock_key); | lock(console_owner); | lock(&port_lock_key); | lock(console_owner); | | *** DEADLOCK *** The issue being that CPU0 takes 'port_lock' on the irq path in pl011_int() before taking 'console_owner' on the printk() path, whereas CPU1 takes the two locks in the opposite order on the printk() path due to setting the "console_owner" prior to calling into into the actual console driver. Fix this in the same way as the msm-serial driver by dropping 'port_lock' before handling the sysrq. Cc: <stable@vger.kernel.org> # 4.19+ Cc: Russell King <linux@armlinux.org.uk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20200811101313.GA6970@willie-the-truck Signed-off-by: Peter Zijlstra <peterz@infradead.org> Tested-by: Will Deacon <will@kernel.org> Signed-off-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20200930120432.16551-1-will@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 534cf755d9df99e214ddbe26b91cd4d81d2603e2 upstream.

Issuing a magic-sysrq via the PL011 causes the following lockdep splat,
which is easily reproducible under QEMU:

  | sysrq: Changing Loglevel
  | sysrq: Loglevel set to 9
  |
  | ======================================================
  | WARNING: possible circular locking dependency detected
  | 5.9.0-rc7 #1 Not tainted
  | ------------------------------------------------------
  | systemd-journal/138 is trying to acquire lock:
  | ffffab133ad950c0 (console_owner){-.-.}-{0:0}, at: console_lock_spinning_enable+0x34/0x70
  |
  | but task is already holding lock:
  | ffff0001fd47b098 (&port_lock_key){-.-.}-{2:2}, at: pl011_int+0x40/0x488
  |
  | which lock already depends on the new lock.

  [...]

  |  Possible unsafe locking scenario:
  |
  |        CPU0                    CPU1
  |        ----                    ----
  |   lock(&port_lock_key);
  |                                lock(console_owner);
  |                                lock(&port_lock_key);
  |   lock(console_owner);
  |
  |  *** DEADLOCK ***

The issue being that CPU0 takes 'port_lock' on the irq path in pl011_int()
before taking 'console_owner' on the printk() path, whereas CPU1 takes
the two locks in the opposite order on the printk() path due to setting
the "console_owner" prior to calling into into the actual console driver.

Fix this in the same way as the msm-serial driver by dropping 'port_lock'
before handling the sysrq.

Cc: <stable@vger.kernel.org> # 4.19+
Cc: Russell King <linux@armlinux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20200811101313.GA6970@willie-the-truck
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200930120432.16551-1-will@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: qcom_geni_serial: To correct QUP Version detection logic 2020-11-01T11:01:06+00:00 Paras Sharma parashar@codeaurora.org 2020-09-30T06:05:26+00:00 44ef3b63c788a72266a124022569fff785d2b7c4 commit c9ca43d42ed8d5fd635d327a664ed1d8579eb2af upstream. For QUP IP versions 2.5 and above the oversampling rate is halved from 32 to 16. Commit ce734600545f ("tty: serial: qcom_geni_serial: Update the oversampling rate") is pushed to handle this scenario. But the existing logic is failing to classify QUP Version 3.0 into the correct group ( 2.5 and above). As result Serial Engine clocks are not configured properly for baud rate and garbage data is sampled to FIFOs from the line. So, fix the logic to detect QUP with versions 2.5 and above. Fixes: ce734600545f ("tty: serial: qcom_geni_serial: Update the oversampling rate") Cc: stable <stable@vger.kernel.org> Signed-off-by: Paras Sharma <parashar@codeaurora.org> Reviewed-by: Akash Asthana <akashast@codeaurora.org> Link: https://lore.kernel.org/r/1601445926-23673-1-git-send-email-parashar@codeaurora.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c9ca43d42ed8d5fd635d327a664ed1d8579eb2af upstream.

For QUP IP versions 2.5 and above the oversampling rate is
halved from 32 to 16.

Commit ce734600545f ("tty: serial: qcom_geni_serial: Update
the oversampling rate") is pushed to handle this scenario.
But the existing logic is failing to classify QUP Version 3.0
into the correct group ( 2.5 and above).

As result Serial Engine clocks are not configured properly for
baud rate and garbage data is sampled to FIFOs from the line.

So, fix the logic to detect QUP with versions 2.5 and above.

Fixes: ce734600545f ("tty: serial: qcom_geni_serial: Update the oversampling rate")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Paras Sharma <parashar@codeaurora.org>
Reviewed-by: Akash Asthana <akashast@codeaurora.org>
Link: https://lore.kernel.org/r/1601445926-23673-1-git-send-email-parashar@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: fsl_lpuart: fix lpuart32_poll_get_char 2020-10-29T08:58:10+00:00 Peng Fan peng.fan@nxp.com 2020-09-29T09:55:09+00:00 1d2ce4350a01df7bf58235933e3042911b6f7b32 commit 29788ab1d2bf26c130de8f44f9553ee78a27e8d5 upstream. The watermark is set to 1, so we need to input two chars to trigger RDRF using the original logic. With the new logic, we could always get the char when there is data in FIFO. Suggested-by: Fugang Duan <fugang.duan@nxp.com> Signed-off-by: Peng Fan <peng.fan@nxp.com> Link: https://lore.kernel.org/r/20200929095509.21680-1-peng.fan@nxp.com Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 29788ab1d2bf26c130de8f44f9553ee78a27e8d5 upstream.

The watermark is set to 1, so we need to input two chars to trigger RDRF
using the original logic. With the new logic, we could always get the
char when there is data in FIFO.

Suggested-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20200929095509.21680-1-peng.fan@nxp.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: lpuart: fix lpuart32_write usage 2020-10-29T08:58:10+00:00 Peng Fan peng.fan@nxp.com 2020-09-29T09:19:20+00:00 231146202650bd171e13f47856069d5e08837412 commit 9ea40db477c024dcb87321b7f32bd6ea12130ac2 upstream. The 2nd and 3rd parameter were wrongly used, and cause kernel abort when doing kgdb debug. Fixes: 1da17d7cf8e2 ("tty: serial: fsl_lpuart: Use appropriate lpuart32_* I/O funcs") Cc: stable <stable@vger.kernel.org> Signed-off-by: Peng Fan <peng.fan@nxp.com> Link: https://lore.kernel.org/r/20200929091920.22612-1-peng.fan@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9ea40db477c024dcb87321b7f32bd6ea12130ac2 upstream.

The 2nd and 3rd parameter were wrongly used, and cause kernel abort when
doing kgdb debug.

Fixes: 1da17d7cf8e2 ("tty: serial: fsl_lpuart: Use appropriate lpuart32_* I/O funcs")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20200929091920.22612-1-peng.fan@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: earlycon dependency 2020-10-29T08:57:37+00:00 Tong Zhang ztong0001@gmail.com 2020-08-28T12:39:50+00:00 f3f79d92ca718e24323b8370756b9bb80453a479 [ Upstream commit 0fb9342d06b0f667b915ba58bfefc030e534a218 ] parse_options() in drivers/tty/serial/earlycon.c calls uart_parse_earlycon in drivers/tty/serial/serial_core.c therefore selecting SERIAL_EARLYCON should automatically select SERIAL_CORE, otherwise will result in symbol not found error during linking if SERIAL_CORE is not configured as builtin Fixes: 9aac5887595b ("tty/serial: add generic serial earlycon") Signed-off-by: Tong Zhang <ztong0001@gmail.com> Link: https://lore.kernel.org/r/20200828123949.2642-1-ztong0001@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 0fb9342d06b0f667b915ba58bfefc030e534a218 ]

parse_options() in drivers/tty/serial/earlycon.c calls uart_parse_earlycon
in drivers/tty/serial/serial_core.c therefore selecting SERIAL_EARLYCON
should automatically select SERIAL_CORE, otherwise will result in symbol
not found error during linking if SERIAL_CORE is not configured as builtin

Fixes: 9aac5887595b ("tty/serial: add generic serial earlycon")
Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Link: https://lore.kernel.org/r/20200828123949.2642-1-ztong0001@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
tty: serial: samsung: Correct clock selection logic 2020-10-01T11:18:00+00:00 Jonathan Bakker xc-racer2@live.ca 2020-05-09T01:34:33+00:00 942a6ff2146a9d65ba3c13822143827c6ad31d59 [ Upstream commit 7d31676a8d91dd18e08853efd1cb26961a38c6a6 ] Some variants of the samsung tty driver can pick which clock to use for their baud rate generation. In the DT conversion, a default clock was selected to be used if a specific one wasn't assigned and then a comparison of which clock rate worked better was done. Unfortunately, the comparison was implemented in such a way that only the default clock was ever actually compared. Fix this by iterating through all possible clocks, except when a specific clock has already been picked via clk_sel (which is only possible via board files). Signed-off-by: Jonathan Bakker <xc-racer2@live.ca> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Link: https://lore.kernel.org/r/BN6PR04MB06604E63833EA41837EBF77BA3A30@BN6PR04MB0660.namprd04.prod.outlook.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7d31676a8d91dd18e08853efd1cb26961a38c6a6 ]

Some variants of the samsung tty driver can pick which clock
to use for their baud rate generation.  In the DT conversion,
a default clock was selected to be used if a specific one wasn't
assigned and then a comparison of which clock rate worked better
was done.  Unfortunately, the comparison was implemented in such
a way that only the default clock was ever actually compared.
Fix this by iterating through all possible clocks, except when a
specific clock has already been picked via clk_sel (which is
only possible via board files).

Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/BN6PR04MB06604E63833EA41837EBF77BA3A30@BN6PR04MB0660.namprd04.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>