From 6a7b9f002eca6788d346c16a6ff0c218b41f8d1d Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 26 Jan 2022 14:33:58 +0100 Subject: Revert "tty: serial: Use fifo in 8250 console driver" This reverts commit 5021d709b31b8a14317998a33cbc78be0de9ab30. The patch is still a bit buggy, and this breaks some other hardware types. It needs to be resubmitted in a non-buggy way, and make sure the other hardware types also continue to work properly. Fixes: 5021d709b31b ("tty: serial: Use fifo in 8250 console driver") Reported-by: Sebastian Andrzej Siewior Reported-by: Jon Hunter Link: https://lore.kernel.org/r/Ye/1+Z8mEzbKbrqG@linutronix.de Link: https://lore.kernel.org/r/a1ac6254-f79e-d131-fa2a-c7ad714c6d4a@nvidia.com Cc: Wander Lairson Costa Cc: Andy Shevchenko Cc: Jiri Slaby Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_port.c | 61 ++++--------------------------------- 1 file changed, 6 insertions(+), 55 deletions(-) diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 2abb3de11a48..3b12bfc1ed67 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -2056,7 +2056,10 @@ static void serial8250_break_ctl(struct uart_port *port, int break_state) serial8250_rpm_put(up); } -static void wait_for_lsr(struct uart_8250_port *up, int bits) +/* + * Wait for transmitter & holding register to empty + */ +static void wait_for_xmitr(struct uart_8250_port *up, int bits) { unsigned int status, tmout = 10000; @@ -2073,16 +2076,6 @@ static void wait_for_lsr(struct uart_8250_port *up, int bits) udelay(1); touch_nmi_watchdog(); } -} - -/* - * Wait for transmitter & holding register to empty - */ -static void wait_for_xmitr(struct uart_8250_port *up, int bits) -{ - unsigned int tmout; - - wait_for_lsr(up, bits); /* Wait up to 1s for flow control if necessary */ if (up->port.flags & UPF_CONS_FLOW) { @@ -3332,35 +3325,6 @@ static void serial8250_console_restore(struct uart_8250_port *up) serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS); } -/* - * Print a string to the serial port using the device FIFO - * - * It sends fifosize bytes and then waits for the fifo - * to get empty. - */ -static void serial8250_console_fifo_write(struct uart_8250_port *up, - const char *s, unsigned int count) -{ - int i; - const char *end = s + count; - unsigned int fifosize = up->port.fifosize; - bool cr_sent = false; - - while (s != end) { - wait_for_lsr(up, UART_LSR_THRE); - - for (i = 0; i < fifosize && s != end; ++i) { - if (*s == '\n' && !cr_sent) { - serial_out(up, UART_TX, '\r'); - cr_sent = true; - } else { - serial_out(up, UART_TX, *s++); - cr_sent = false; - } - } - } -} - /* * Print a string to the serial port trying not to disturb * any possible real use of the port... @@ -3376,7 +3340,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s, struct uart_8250_em485 *em485 = up->em485; struct uart_port *port = &up->port; unsigned long flags; - unsigned int ier, use_fifo; + unsigned int ier; int locked = 1; touch_nmi_watchdog(); @@ -3408,20 +3372,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s, mdelay(port->rs485.delay_rts_before_send); } - use_fifo = (up->capabilities & UART_CAP_FIFO) && - port->fifosize > 1 && - (serial_port_in(port, UART_FCR) & UART_FCR_ENABLE_FIFO) && - /* - * After we put a data in the fifo, the controller will send - * it regardless of the CTS state. Therefore, only use fifo - * if we don't use control flow. - */ - !(up->port.flags & UPF_CONS_FLOW); - - if (likely(use_fifo)) - serial8250_console_fifo_write(up, s, count); - else - uart_console_write(port, s, count, serial8250_console_putchar); + uart_console_write(port, s, count, serial8250_console_putchar); /* * Finally, wait for transmitter to become empty -- cgit v1.2.3 From 152d1afa834c84530828ee031cf07a00e0fc0b8c Mon Sep 17 00:00:00 2001 From: Cameron Williams Date: Mon, 24 Jan 2022 09:42:23 +0000 Subject: tty: Add support for Brainboxes UC cards. This commit adds support for the some of the Brainboxes PCI range of cards, including the UC-101, UC-235/246, UC-257, UC-268, UC-275/279, UC-302, UC-310, UC-313, UC-320/324, UC-346, UC-357, UC-368 and UC-420/431. Signed-off-by: Cameron Williams Cc: stable Link: https://lore.kernel.org/r/AM5PR0202MB2564688493F7DD9B9C610827C45E9@AM5PR0202MB2564.eurprd02.prod.outlook.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_pci.c | 100 ++++++++++++++++++++++++++++++++++++- 1 file changed, 98 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c index e8b5469e9dfa..e17e97ea86fa 100644 --- a/drivers/tty/serial/8250/8250_pci.c +++ b/drivers/tty/serial/8250/8250_pci.c @@ -4779,8 +4779,30 @@ static const struct pci_device_id serial_pci_tbl[] = { { PCI_VENDOR_ID_INTASHIELD, PCI_DEVICE_ID_INTASHIELD_IS400, PCI_ANY_ID, PCI_ANY_ID, 0, 0, /* 135a.0dc0 */ pbn_b2_4_115200 }, + /* Brainboxes Devices */ /* - * BrainBoxes UC-260 + * Brainboxes UC-101 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x0BA1, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_2_115200 }, + /* + * Brainboxes UC-235/246 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x0AA1, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_1_115200 }, + /* + * Brainboxes UC-257 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x0861, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_2_115200 }, + /* + * Brainboxes UC-260/271/701/756 */ { PCI_VENDOR_ID_INTASHIELD, 0x0D21, PCI_ANY_ID, PCI_ANY_ID, @@ -4788,7 +4810,81 @@ static const struct pci_device_id serial_pci_tbl[] = { pbn_b2_4_115200 }, { PCI_VENDOR_ID_INTASHIELD, 0x0E34, PCI_ANY_ID, PCI_ANY_ID, - PCI_CLASS_COMMUNICATION_MULTISERIAL << 8, 0xffff00, + PCI_CLASS_COMMUNICATION_MULTISERIAL << 8, 0xffff00, + pbn_b2_4_115200 }, + /* + * Brainboxes UC-268 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x0841, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_4_115200 }, + /* + * Brainboxes UC-275/279 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x0881, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_8_115200 }, + /* + * Brainboxes UC-302 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x08E1, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_2_115200 }, + /* + * Brainboxes UC-310 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x08C1, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_2_115200 }, + /* + * Brainboxes UC-313 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x08A3, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_2_115200 }, + /* + * Brainboxes UC-320/324 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x0A61, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_1_115200 }, + /* + * Brainboxes UC-346 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x0B02, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_4_115200 }, + /* + * Brainboxes UC-357 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x0A81, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_2_115200 }, + { PCI_VENDOR_ID_INTASHIELD, 0x0A83, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_2_115200 }, + /* + * Brainboxes UC-368 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x0C41, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, + pbn_b2_4_115200 }, + /* + * Brainboxes UC-420/431 + */ + { PCI_VENDOR_ID_INTASHIELD, 0x0921, + PCI_ANY_ID, PCI_ANY_ID, + 0, 0, pbn_b2_4_115200 }, /* * Perle PCI-RAS cards -- cgit v1.2.3 From f23653fe64479d96910bfda2b700b1af17c991ac Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Wed, 26 Jan 2022 09:22:54 +0000 Subject: tty: Partially revert the removal of the Cyclades public API Fix a user API regression introduced with commit f76edd8f7ce0 ("tty: cyclades, remove this orphan"), which removed a part of the API and caused compilation errors for user programs using said part, such as GCC 9 in its libsanitizer component[1]: .../libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc:160:10: fatal error: linux/cyclades.h: No such file or directory 160 | #include | ^~~~~~~~~~~~~~~~~~ compilation terminated. make[4]: *** [Makefile:664: sanitizer_platform_limits_posix.lo] Error 1 As the absolute minimum required bring `struct cyclades_monitor' and ioctl numbers back then so as to make the library build again. Add a preprocessor warning as to the obsolescence of the features provided. References: [1] GCC PR sanitizer/100379, "cyclades.h is removed from linux kernel header files", Fixes: f76edd8f7ce0 ("tty: cyclades, remove this orphan") Cc: stable@vger.kernel.org # v5.13+ Reviewed-by: Christoph Hellwig Signed-off-by: Maciej W. Rozycki Link: https://lore.kernel.org/r/alpine.DEB.2.20.2201260733430.11348@tpp.orcam.me.uk Signed-off-by: Greg Kroah-Hartman --- include/uapi/linux/cyclades.h | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 include/uapi/linux/cyclades.h diff --git a/include/uapi/linux/cyclades.h b/include/uapi/linux/cyclades.h new file mode 100644 index 000000000000..6225c5aebe06 --- /dev/null +++ b/include/uapi/linux/cyclades.h @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ + +#ifndef _UAPI_LINUX_CYCLADES_H +#define _UAPI_LINUX_CYCLADES_H + +#warning "Support for features provided by this header has been removed" +#warning "Please consider updating your code" + +struct cyclades_monitor { + unsigned long int_count; + unsigned long char_count; + unsigned long char_max; + unsigned long char_last; +}; + +#define CYGETMON 0x435901 +#define CYGETTHRESH 0x435902 +#define CYSETTHRESH 0x435903 +#define CYGETDEFTHRESH 0x435904 +#define CYSETDEFTHRESH 0x435905 +#define CYGETTIMEOUT 0x435906 +#define CYSETTIMEOUT 0x435907 +#define CYGETDEFTIMEOUT 0x435908 +#define CYSETDEFTIMEOUT 0x435909 +#define CYSETRFLOW 0x43590a +#define CYGETRFLOW 0x43590b +#define CYSETRTSDTR_INV 0x43590c +#define CYGETRTSDTR_INV 0x43590d +#define CYZSETPOLLCYCLE 0x43590e +#define CYZGETPOLLCYCLE 0x43590f +#define CYGETCD1400VER 0x435910 +#define CYSETWAIT 0x435912 +#define CYGETWAIT 0x435913 + +#endif /* _UAPI_LINUX_CYCLADES_H */ -- cgit v1.2.3 From db7f19c0aa0abcb751ff0ed694a071363f702b1d Mon Sep 17 00:00:00 2001 From: Arnaud Pouliquen Date: Tue, 4 Jan 2022 17:35:45 +0100 Subject: tty: rpmsg: Fix race condition releasing tty port The tty_port struct is part of the rpmsg_tty_port structure. The issue is that the rpmsg_tty_port structure is freed on rpmsg_tty_remove while it is still referenced in the tty_struct. Its release is not predictable due to workqueues. For instance following ftrace shows that rpmsg_tty_close is called after rpmsg_tty_release_cport: nr_test.sh-389 [000] ..... 212.093752: rpmsg_tty_remove <-rpmsg_dev_ remove cat-1191 [001] ..... 212.095697: tty_release <-__fput nr_test.sh-389 [000] ..... 212.099166: rpmsg_tty_release_cport <-rpm sg_tty_remove cat-1191 [001] ..... 212.115352: rpmsg_tty_close <-tty_release cat-1191 [001] ..... 212.115371: release_tty <-tty_release_str As consequence, the port must be free only when user has released the TTY interface. This path : - Introduce the .destruct port tty ops function to release the allocated rpmsg_tty_port structure. - Introduce the .hangup tty ops function to call tty_port_hangup. - Manages the tty port refcounting to trig the .destruct port ops, - Introduces the rpmsg_tty_cleanup function to ensure that the TTY is removed before decreasing the port refcount. Fixes: 7c0408d80579 ("tty: add rpmsg driver") Cc: stable Signed-off-by: Arnaud Pouliquen Link: https://lore.kernel.org/r/20220104163545.34710-1-arnaud.pouliquen@foss.st.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/rpmsg_tty.c | 40 ++++++++++++++++++++++++++-------------- 1 file changed, 26 insertions(+), 14 deletions(-) diff --git a/drivers/tty/rpmsg_tty.c b/drivers/tty/rpmsg_tty.c index dae2a4e44f38..29db413bbc03 100644 --- a/drivers/tty/rpmsg_tty.c +++ b/drivers/tty/rpmsg_tty.c @@ -50,10 +50,17 @@ static int rpmsg_tty_cb(struct rpmsg_device *rpdev, void *data, int len, void *p static int rpmsg_tty_install(struct tty_driver *driver, struct tty_struct *tty) { struct rpmsg_tty_port *cport = idr_find(&tty_idr, tty->index); + struct tty_port *port; tty->driver_data = cport; - return tty_port_install(&cport->port, driver, tty); + port = tty_port_get(&cport->port); + return tty_port_install(port, driver, tty); +} + +static void rpmsg_tty_cleanup(struct tty_struct *tty) +{ + tty_port_put(tty->port); } static int rpmsg_tty_open(struct tty_struct *tty, struct file *filp) @@ -106,12 +113,19 @@ static unsigned int rpmsg_tty_write_room(struct tty_struct *tty) return size; } +static void rpmsg_tty_hangup(struct tty_struct *tty) +{ + tty_port_hangup(tty->port); +} + static const struct tty_operations rpmsg_tty_ops = { .install = rpmsg_tty_install, .open = rpmsg_tty_open, .close = rpmsg_tty_close, .write = rpmsg_tty_write, .write_room = rpmsg_tty_write_room, + .hangup = rpmsg_tty_hangup, + .cleanup = rpmsg_tty_cleanup, }; static struct rpmsg_tty_port *rpmsg_tty_alloc_cport(void) @@ -137,8 +151,10 @@ static struct rpmsg_tty_port *rpmsg_tty_alloc_cport(void) return cport; } -static void rpmsg_tty_release_cport(struct rpmsg_tty_port *cport) +static void rpmsg_tty_destruct_port(struct tty_port *port) { + struct rpmsg_tty_port *cport = container_of(port, struct rpmsg_tty_port, port); + mutex_lock(&idr_lock); idr_remove(&tty_idr, cport->id); mutex_unlock(&idr_lock); @@ -146,7 +162,10 @@ static void rpmsg_tty_release_cport(struct rpmsg_tty_port *cport) kfree(cport); } -static const struct tty_port_operations rpmsg_tty_port_ops = { }; +static const struct tty_port_operations rpmsg_tty_port_ops = { + .destruct = rpmsg_tty_destruct_port, +}; + static int rpmsg_tty_probe(struct rpmsg_device *rpdev) { @@ -166,7 +185,8 @@ static int rpmsg_tty_probe(struct rpmsg_device *rpdev) cport->id, dev); if (IS_ERR(tty_dev)) { ret = dev_err_probe(dev, PTR_ERR(tty_dev), "Failed to register tty port\n"); - goto err_destroy; + tty_port_put(&cport->port); + return ret; } cport->rpdev = rpdev; @@ -177,12 +197,6 @@ static int rpmsg_tty_probe(struct rpmsg_device *rpdev) rpdev->src, rpdev->dst, cport->id); return 0; - -err_destroy: - tty_port_destroy(&cport->port); - rpmsg_tty_release_cport(cport); - - return ret; } static void rpmsg_tty_remove(struct rpmsg_device *rpdev) @@ -192,13 +206,11 @@ static void rpmsg_tty_remove(struct rpmsg_device *rpdev) dev_dbg(&rpdev->dev, "Removing rpmsg tty device %d\n", cport->id); /* User hang up to release the tty */ - if (tty_port_initialized(&cport->port)) - tty_port_tty_hangup(&cport->port, false); + tty_port_tty_hangup(&cport->port, false); tty_unregister_device(rpmsg_tty_driver, cport->id); - tty_port_destroy(&cport->port); - rpmsg_tty_release_cport(cport); + tty_port_put(&cport->port); } static struct rpmsg_device_id rpmsg_driver_tty_id_table[] = { -- cgit v1.2.3 From d06b1cf28297e27127d3da54753a3a01a2fa2f28 Mon Sep 17 00:00:00 2001 From: Robert Hancock Date: Wed, 12 Jan 2022 13:42:14 -0600 Subject: serial: 8250: of: Fix mapped region size when using reg-offset property 8250_of supports a reg-offset property which is intended to handle cases where the device registers start at an offset inside the region of memory allocated to the device. The Xilinx 16550 UART, for which this support was initially added, requires this. However, the code did not adjust the overall size of the mapped region accordingly, causing the driver to request an area of memory past the end of the device's allocation. For example, if the UART was allocated an address of 0xb0130000, size of 0x10000 and reg-offset of 0x1000 in the device tree, the region of memory reserved was b0131000-b0140fff, which caused the driver for the region starting at b0140000 to fail to probe. Fix this by subtracting reg-offset from the mapped region size. Fixes: b912b5e2cfb3 ([POWERPC] Xilinx: of_serial support for Xilinx uart 16550.) Cc: stable Signed-off-by: Robert Hancock Link: https://lore.kernel.org/r/20220112194214.881844-1-robert.hancock@calian.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_of.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c index bce28729dd7b..be8626234627 100644 --- a/drivers/tty/serial/8250/8250_of.c +++ b/drivers/tty/serial/8250/8250_of.c @@ -83,8 +83,17 @@ static int of_platform_serial_setup(struct platform_device *ofdev, port->mapsize = resource_size(&resource); /* Check for shifted address mapping */ - if (of_property_read_u32(np, "reg-offset", &prop) == 0) + if (of_property_read_u32(np, "reg-offset", &prop) == 0) { + if (prop >= port->mapsize) { + dev_warn(&ofdev->dev, "reg-offset %u exceeds region size %pa\n", + prop, &port->mapsize); + ret = -EINVAL; + goto err_unprepare; + } + port->mapbase += prop; + port->mapsize -= prop; + } port->iotype = UPIO_MEM; if (of_property_read_u32(np, "reg-io-width", &prop) == 0) { -- cgit v1.2.3 From 8838b2af23caf1ff0610caef2795d6668a013b2d Mon Sep 17 00:00:00 2001 From: "daniel.starke@siemens.com" Date: Thu, 20 Jan 2022 02:18:57 -0800 Subject: tty: n_gsm: fix SW flow control encoding/handling n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010. See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516 The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to the newer 27.010 here. Chapter 5.2.7.3 states that DC1 (XON) and DC3 (XOFF) are the control characters defined in ISO/IEC 646. These shall be quoted if seen in the data stream to avoid interpretation as flow control characters. ISO/IEC 646 refers to the set of ISO standards described as the ISO 7-bit coded character set for information interchange. Its final version is also known as ITU T.50. See https://www.itu.int/rec/T-REC-T.50-199209-I/en To abide the standard it is needed to quote DC1 and DC3 correctly if these are seen as data bytes and not as control characters. The current implementation already tries to enforce this but fails to catch all defined cases. 3GPP 27.010 chapter 5.2.7.3 clearly states that the most significant bit shall be ignored for DC1 and DC3 handling. The current implementation handles only the case with the most significant bit set 0. Cases in which DC1 and DC3 have the most significant bit set 1 are left unhandled. This patch fixes this by masking the data bytes with ISO_IEC_646_MASK (only the 7 least significant bits set 1) before comparing them with XON (a.k.a. DC1) and XOFF (a.k.a. DC3) when testing which byte values need quotation via byte stuffing. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Cc: stable@vger.kernel.org Signed-off-by: Daniel Starke Link: https://lore.kernel.org/r/20220120101857.2509-1-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_gsm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index ba27b274c967..0b1808e3a912 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -322,6 +322,7 @@ static int addr_cnt; #define GSM1_ESCAPE_BITS 0x20 #define XON 0x11 #define XOFF 0x13 +#define ISO_IEC_646_MASK 0x7F static const struct tty_port_operations gsm_port_ops; @@ -531,7 +532,8 @@ static int gsm_stuff_frame(const u8 *input, u8 *output, int len) int olen = 0; while (len--) { if (*input == GSM1_SOF || *input == GSM1_ESCAPE - || *input == XON || *input == XOFF) { + || (*input & ISO_IEC_646_MASK) == XON + || (*input & ISO_IEC_646_MASK) == XOFF) { *output++ = GSM1_ESCAPE; *output++ = *input++ ^ GSM1_ESCAPE_BITS; olen++; -- cgit v1.2.3 From d3d079bde07e1b7deaeb57506dc0b86010121d17 Mon Sep 17 00:00:00 2001 From: Valentin Caron Date: Tue, 11 Jan 2022 17:44:40 +0100 Subject: serial: stm32: prevent TDR register overwrite when sending x_char When sending x_char in stm32_usart_transmit_chars(), driver can overwrite the value of TDR register by the value of x_char. If this happens, the previous value that was present in TDR register will not be sent through uart. This code checks if the previous value in TDR register is sent before writing the x_char value into register. Fixes: 48a6092fb41f ("serial: stm32-usart: Add STM32 USART Driver") Cc: stable Signed-off-by: Valentin Caron Link: https://lore.kernel.org/r/20220111164441.6178-2-valentin.caron@foss.st.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/stm32-usart.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 1f89ab0e49ac..c1b8828451c8 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -550,11 +550,23 @@ static void stm32_usart_transmit_chars(struct uart_port *port) struct stm32_port *stm32_port = to_stm32_port(port); const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs; struct circ_buf *xmit = &port->state->xmit; + u32 isr; + int ret; if (port->x_char) { if (stm32_usart_tx_dma_started(stm32_port) && stm32_usart_tx_dma_enabled(stm32_port)) stm32_usart_clr_bits(port, ofs->cr3, USART_CR3_DMAT); + + /* Check that TDR is empty before filling FIFO */ + ret = + readl_relaxed_poll_timeout_atomic(port->membase + ofs->isr, + isr, + (isr & USART_SR_TXE), + 10, 1000); + if (ret) + dev_warn(port->dev, "1 character may be erased\n"); + writel_relaxed(port->x_char, port->membase + ofs->tdr); port->x_char = 0; port->icount.tx++; -- cgit v1.2.3 From 037b91ec7729524107982e36ec4b40f9b174f7a2 Mon Sep 17 00:00:00 2001 From: Valentin Caron Date: Tue, 11 Jan 2022 17:44:41 +0100 Subject: serial: stm32: fix software flow control transfer x_char is ignored by stm32_usart_start_tx() when xmit buffer is empty. Fix start_tx condition to allow x_char to be sent. Fixes: 48a6092fb41f ("serial: stm32-usart: Add STM32 USART Driver") Cc: stable Signed-off-by: Erwan Le Ray Signed-off-by: Valentin Caron Link: https://lore.kernel.org/r/20220111164441.6178-3-valentin.caron@foss.st.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/stm32-usart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index c1b8828451c8..9570002d07e7 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -742,7 +742,7 @@ static void stm32_usart_start_tx(struct uart_port *port) struct serial_rs485 *rs485conf = &port->rs485; struct circ_buf *xmit = &port->state->xmit; - if (uart_circ_empty(xmit)) + if (uart_circ_empty(xmit) && !port->x_char) return; if (rs485conf->flags & SER_RS485_ENABLED) { -- cgit v1.2.3 From 62f676ff7898f6c1bd26ce014564773a3dc00601 Mon Sep 17 00:00:00 2001 From: Jochen Mades Date: Sat, 23 Jan 2021 05:10:14 +0100 Subject: serial: pl011: Fix incorrect rs485 RTS polarity on set_mctrl Commit 8d479237727c ("serial: amba-pl011: add RS485 support") sought to keep RTS deasserted on set_mctrl if rs485 is enabled. However it did so only if deasserted RTS polarity is high. Fix it in case it's low. Fixes: 8d479237727c ("serial: amba-pl011: add RS485 support") Cc: stable@vger.kernel.org # v5.15+ Cc: Lino Sanfilippo Signed-off-by: Jochen Mades [lukas: copyedit commit message, add stable designation] Signed-off-by: Lukas Wunner Link: https://lore.kernel.org/r/85fa3323ba8c307943969b7343e23f34c3e652ba.1642909284.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/amba-pl011.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 1f1df46242f9..f64c475a1379 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1582,8 +1582,12 @@ static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl) container_of(port, struct uart_amba_port, port); unsigned int cr; - if (port->rs485.flags & SER_RS485_ENABLED) - mctrl &= ~TIOCM_RTS; + if (port->rs485.flags & SER_RS485_ENABLED) { + if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) + mctrl &= ~TIOCM_RTS; + else + mctrl |= TIOCM_RTS; + } cr = pl011_read(uap, REG_CR); -- cgit v1.2.3 From 2dd8a74fddd21b95dcc60a2d3c9eaec993419d69 Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Sun, 23 Jan 2022 05:21:14 +0100 Subject: serial: core: Initialize rs485 RTS polarity already on probe RTS polarity of rs485-enabled ports is currently initialized on uart open via: tty_port_open() tty_port_block_til_ready() tty_port_raise_dtr_rts() # if (C_BAUD(tty)) uart_dtr_rts() uart_port_dtr_rts() There's at least three problems here: First, if no baud rate is set, RTS polarity is not initialized. That's the right thing to do for rs232, but not for rs485, which requires that RTS is deasserted unconditionally. Second, if the DeviceTree property "linux,rs485-enabled-at-boot-time" is present, RTS should be deasserted as early as possible, i.e. on probe. Otherwise it may remain asserted until first open. Third, even though RTS is deasserted on open and close, it may subsequently be asserted by uart_throttle(), uart_unthrottle() or uart_set_termios() because those functions aren't rs485-aware. (Only uart_tiocmset() is.) To address these issues, move RTS initialization from uart_port_dtr_rts() to uart_configure_port(). Prevent subsequent modification of RTS polarity by moving the existing rs485 check from uart_tiocmget() to uart_update_mctrl(). That way, RTS is initialized on probe and then remains unmodified unless the uart transmits data. If rs485 is enabled at runtime (instead of at boot) through a TIOCSRS485 ioctl(), RTS is initialized by the uart driver's ->rs485_config() callback and then likewise remains unmodified. The PL011 driver initializes RTS on uart open and prevents subsequent modification in its ->set_mctrl() callback. That code is obsoleted by the present commit, so drop it. Cc: Jan Kiszka Cc: Su Bao Cheng Signed-off-by: Lukas Wunner Link: https://lore.kernel.org/r/2d2acaf3a69e89b7bf687c912022b11fd29dfa1e.1642909284.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/amba-pl011.c | 15 +-------------- drivers/tty/serial/serial_core.c | 34 ++++++++++++---------------------- 2 files changed, 13 insertions(+), 36 deletions(-) diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index f64c475a1379..ba053a68529f 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1582,13 +1582,6 @@ static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl) container_of(port, struct uart_amba_port, port); unsigned int cr; - if (port->rs485.flags & SER_RS485_ENABLED) { - if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) - mctrl &= ~TIOCM_RTS; - else - mctrl |= TIOCM_RTS; - } - cr = pl011_read(uap, REG_CR); #define TIOCMBIT(tiocmbit, uartbit) \ @@ -1812,14 +1805,8 @@ static int pl011_startup(struct uart_port *port) cr &= UART011_CR_RTS | UART011_CR_DTR; cr |= UART01x_CR_UARTEN | UART011_CR_RXE; - if (port->rs485.flags & SER_RS485_ENABLED) { - if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) - cr &= ~UART011_CR_RTS; - else - cr |= UART011_CR_RTS; - } else { + if (!(port->rs485.flags & SER_RS485_ENABLED)) cr |= UART011_CR_TXE; - } pl011_write(cr, uap, REG_CR); diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index dc40c4155356..0db90be4c3bc 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -144,6 +144,11 @@ uart_update_mctrl(struct uart_port *port, unsigned int set, unsigned int clear) unsigned long flags; unsigned int old; + if (port->rs485.flags & SER_RS485_ENABLED) { + set &= ~TIOCM_RTS; + clear &= ~TIOCM_RTS; + } + spin_lock_irqsave(&port->lock, flags); old = port->mctrl; port->mctrl = (old & ~clear) | set; @@ -157,23 +162,10 @@ uart_update_mctrl(struct uart_port *port, unsigned int set, unsigned int clear) static void uart_port_dtr_rts(struct uart_port *uport, int raise) { - int rs485_on = uport->rs485_config && - (uport->rs485.flags & SER_RS485_ENABLED); - int RTS_after_send = !!(uport->rs485.flags & SER_RS485_RTS_AFTER_SEND); - - if (raise) { - if (rs485_on && RTS_after_send) { - uart_set_mctrl(uport, TIOCM_DTR); - uart_clear_mctrl(uport, TIOCM_RTS); - } else { - uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS); - } - } else { - unsigned int clear = TIOCM_DTR; - - clear |= (!rs485_on || RTS_after_send) ? TIOCM_RTS : 0; - uart_clear_mctrl(uport, clear); - } + if (raise) + uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS); + else + uart_clear_mctrl(uport, TIOCM_DTR | TIOCM_RTS); } /* @@ -1075,11 +1067,6 @@ uart_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear) goto out; if (!tty_io_error(tty)) { - if (uport->rs485.flags & SER_RS485_ENABLED) { - set &= ~TIOCM_RTS; - clear &= ~TIOCM_RTS; - } - uart_update_mctrl(uport, set, clear); ret = 0; } @@ -2390,6 +2377,9 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state, */ spin_lock_irqsave(&port->lock, flags); port->mctrl &= TIOCM_DTR; + if (port->rs485.flags & SER_RS485_ENABLED && + !(port->rs485.flags & SER_RS485_RTS_AFTER_SEND)) + port->mctrl |= TIOCM_RTS; port->ops->set_mctrl(port, port->mctrl); spin_unlock_irqrestore(&port->lock, flags); -- cgit v1.2.3 From d1ad2721b1eb05d54e81393a7ebc332d4a35c68f Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 27 Jan 2022 08:33:04 +0100 Subject: kbuild: remove include/linux/cyclades.h from header file check The file now rightfully throws up a big warning that it should never be included, so remove it from the header_check test. Fixes: f23653fe6447 ("tty: Partially revert the removal of the Cyclades public API") Cc: stable Cc: Masahiro Yamada Cc: "Maciej W. Rozycki" Reported-by: Stephen Rothwell Reported-by: kernel test robot Link: https://lore.kernel.org/r/20220127073304.42399-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- usr/include/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/usr/include/Makefile b/usr/include/Makefile index 7be7468c177b..83822c33e9e7 100644 --- a/usr/include/Makefile +++ b/usr/include/Makefile @@ -28,6 +28,7 @@ no-header-test += linux/am437x-vpfe.h no-header-test += linux/android/binder.h no-header-test += linux/android/binderfs.h no-header-test += linux/coda.h +no-header-test += linux/cyclades.h no-header-test += linux/errqueue.h no-header-test += linux/fsmap.h no-header-test += linux/hdlc/ioctl.h -- cgit v1.2.3