From 52b3bfc69efc44447ed2db25dd999aef64b3c970 Mon Sep 17 00:00:00 2001 From: Lucas Kannebley Tavares Date: Fri, 28 Oct 2011 13:52:08 -0200 Subject: [PATCH 01/13] jsm: Change maintainership Breno Leitao has passed the maintainership on to me. Signed-off-by: Lucas Kannebley Tavares Acked-by: Breno Leitao Signed-off-by: Greg Kroah-Hartman --- MAINTAINERS | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/MAINTAINERS b/MAINTAINERS index 4808256446f2..cc6a46645432 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3710,7 +3710,7 @@ F: fs/jbd2/ F: include/linux/jbd2.h JSM Neo PCI based serial card -M: Breno Leitao +M: Lucas Tavares L: linux-serial@vger.kernel.org S: Maintained F: drivers/tty/serial/jsm/ From c2a3e84f950e7ddba1f3914b005861d46ae60359 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Tue, 25 Oct 2011 19:19:43 -0700 Subject: [PATCH 02/13] tty: hvc_dcc: Fix duplicate character inputs Reading from the DCC grabs a character from the buffer and clears the status bit. Since this is a context-changing operation, instructions following the character read that rely on the status bit being accurate need to be synchronized with an ISB. In this case, the status bit check needs to execute after the character read otherwise we run the risk of reading the character and checking the status bit before the read can clear the status bit in the first place. When this happens, the user will see the same character they typed twice, instead of once. Add an ISB after the read and the write, so that the status check is synchronized with the read/write operations. Signed-off-by: Stephen Boyd Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/hvc/hvc_dcc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/tty/hvc/hvc_dcc.c b/drivers/tty/hvc/hvc_dcc.c index 435f6facbc23..44fbebab5075 100644 --- a/drivers/tty/hvc/hvc_dcc.c +++ b/drivers/tty/hvc/hvc_dcc.c @@ -46,6 +46,7 @@ static inline char __dcc_getchar(void) asm volatile("mrc p14, 0, %0, c0, c5, 0 @ read comms data reg" : "=r" (__c)); + isb(); return __c; } @@ -55,6 +56,7 @@ static inline void __dcc_putchar(char c) asm volatile("mcr p14, 0, %0, c0, c5, 0 @ write a char" : /* no output register */ : "r" (c)); + isb(); } static int hvc_dcc_put_chars(uint32_t vt, const char *buf, int count) From a1d7cfe29f13cf45f8094929864b9c66bf0cd91b Mon Sep 17 00:00:00 2001 From: Tomoya MORINAGA Date: Thu, 27 Oct 2011 15:45:18 +0900 Subject: [PATCH 03/13] pch_uart: Fix hw-flow control issue Using hardware flow control, currently, register of the control-bit(AFE) is not set. This patch fixes the issue. Signed-off-by: Tomoya MORINAGA Acked-by: Alan Cox Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/pch_uart.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c index 21febef926aa..2f07a6702eab 100644 --- a/drivers/tty/serial/pch_uart.c +++ b/drivers/tty/serial/pch_uart.c @@ -1280,6 +1280,7 @@ static void pch_uart_set_termios(struct uart_port *port, if (rtn) goto out; + pch_uart_set_mctrl(&priv->port, priv->port.mctrl); /* Don't rewrite B0 */ if (tty_termios_baud_rate(termios)) tty_termios_encode_baud_rate(termios, baud, baud); From 8249f743f732ccbc3056428945ab1d9bd36d46bf Mon Sep 17 00:00:00 2001 From: Tomoya MORINAGA Date: Fri, 28 Oct 2011 09:38:49 +0900 Subject: [PATCH 04/13] pch_uart: Support new device LAPIS Semiconductor ML7831 IOH ML7831 is companion chip for Intel Atom E6xx series. Signed-off-by: Tomoya MORINAGA Acked-by: Alan Cox Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/Kconfig | 14 +++++++------- drivers/tty/serial/pch_uart.c | 8 ++++++++ 2 files changed, 15 insertions(+), 7 deletions(-) diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 5f479dada6f2..925a1e547a83 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -1560,7 +1560,7 @@ config SERIAL_IFX6X60 Support for the IFX6x60 modem devices on Intel MID platforms. config SERIAL_PCH_UART - tristate "Intel EG20T PCH / OKI SEMICONDUCTOR IOH(ML7213/ML7223) UART" + tristate "Intel EG20T PCH/LAPIS Semicon IOH(ML7213/ML7223/ML7831) UART" depends on PCI select SERIAL_CORE help @@ -1568,12 +1568,12 @@ config SERIAL_PCH_UART which is an IOH(Input/Output Hub) for x86 embedded processor. Enabling PCH_DMA, this PCH UART works as DMA mode. - This driver also can be used for OKI SEMICONDUCTOR IOH(Input/ - Output Hub), ML7213 and ML7223. - ML7213 IOH is for IVI(In-Vehicle Infotainment) use and ML7223 IOH is - for MP(Media Phone) use. - ML7213/ML7223 is companion chip for Intel Atom E6xx series. - ML7213/ML7223 is completely compatible for Intel EG20T PCH. + This driver also can be used for LAPIS Semiconductor IOH(Input/ + Output Hub), ML7213, ML7223 and ML7831. + ML7213 IOH is for IVI(In-Vehicle Infotainment) use, ML7223 IOH is + for MP(Media Phone) use and ML7831 IOH is for general purpose use. + ML7213/ML7223/ML7831 is companion chip for Intel Atom E6xx series. + ML7213/ML7223/ML7831 is completely compatible for Intel EG20T PCH. config SERIAL_MSM_SMD bool "Enable tty device interface for some SMD ports" diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c index 2f07a6702eab..2ef0e7d02991 100644 --- a/drivers/tty/serial/pch_uart.c +++ b/drivers/tty/serial/pch_uart.c @@ -258,6 +258,8 @@ enum pch_uart_num_t { pch_ml7213_uart2, pch_ml7223_uart0, pch_ml7223_uart1, + pch_ml7831_uart0, + pch_ml7831_uart1, }; static struct pch_uart_driver_data drv_dat[] = { @@ -270,6 +272,8 @@ static struct pch_uart_driver_data drv_dat[] = { [pch_ml7213_uart2] = {PCH_UART_2LINE, 2}, [pch_ml7223_uart0] = {PCH_UART_8LINE, 0}, [pch_ml7223_uart1] = {PCH_UART_2LINE, 1}, + [pch_ml7831_uart0] = {PCH_UART_8LINE, 0}, + [pch_ml7831_uart1] = {PCH_UART_2LINE, 1}, }; static unsigned int default_baud = 9600; @@ -1553,6 +1557,10 @@ static DEFINE_PCI_DEVICE_TABLE(pch_uart_pci_id) = { .driver_data = pch_ml7223_uart0}, {PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x800D), .driver_data = pch_ml7223_uart1}, + {PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8811), + .driver_data = pch_ml7831_uart0}, + {PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8812), + .driver_data = pch_ml7831_uart1}, {0,}, }; From eca9dfa846a3d0eeb865e290851f4bfe4fb34fdd Mon Sep 17 00:00:00 2001 From: Tomoya MORINAGA Date: Fri, 28 Oct 2011 09:38:50 +0900 Subject: [PATCH 05/13] pch_uart: Change company name OKI SEMICONDUCTOR to LAPIS Semiconductor On October 1 in 2011, OKI SEMICONDUCTOR Co., Ltd. changed the company name in to LAPIS Semiconductor Co., Ltd. Signed-off-by: Tomoya MORINAGA Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/pch_uart.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c index 2ef0e7d02991..ac852b5a8f93 100644 --- a/drivers/tty/serial/pch_uart.c +++ b/drivers/tty/serial/pch_uart.c @@ -1,5 +1,5 @@ /* - *Copyright (C) 2010 OKI SEMICONDUCTOR CO., LTD. + *Copyright (C) 2011 LAPIS Semiconductor Co., Ltd. * *This program is free software; you can redistribute it and/or modify *it under the terms of the GNU General Public License as published by @@ -46,8 +46,8 @@ enum { /* Set the max number of UART port * Intel EG20T PCH: 4 port - * OKI SEMICONDUCTOR ML7213 IOH: 3 port - * OKI SEMICONDUCTOR ML7223 IOH: 2 port + * LAPIS Semiconductor ML7213 IOH: 3 port + * LAPIS Semiconductor ML7223 IOH: 2 port */ #define PCH_UART_NR 4 From 9636b755da7b498094bdf15b4ce9f6fd16995e4e Mon Sep 17 00:00:00 2001 From: Doug Anderson Date: Tue, 11 Oct 2011 17:05:43 -0700 Subject: [PATCH 06/13] tty/serial: Prevent drop of DCD on suspend for Tegra UARTs On Tegra UARTs (except UART1), the DTR / DCD / DSR lines are not externally accessible. Instead, the DTR line internally appears to be looped back to be the input to the DCD and DSR lines. The net effect of this is that when we drop DTR (like when we suspend), we'll see DCD drop too. ...and when we see DCD drop, we treat that as a hangup. In order to prevent this hangup from occurring at every sleep, we need to force DTR to remain high on Tegra UARTs. This patch uses the mcr_mask / mcr_force fields, which were originally added for the kludge ALPHA_KLUDGE_MCR. Using these fields does not prevent us from removing ALPHA_KLUDGE_MCR--we can just remove the "if" tests I have added and always init mcr_mask / mcr_force from the serial8250_config. NOTE: If we have people that are using UARTA on a Tegra and need to control DTR, we'll need to either add a separate port type for UARTA or we'll need to add some tegra-specific code to detect whether the DTR needs to be left high. Signed-off-by: Doug Anderson Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250.c | 14 ++++++++++++++ drivers/tty/serial/8250.h | 2 ++ 2 files changed, 16 insertions(+) diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c index eeadf1b8e093..2b0a4b63c5f7 100644 --- a/drivers/tty/serial/8250.c +++ b/drivers/tty/serial/8250.c @@ -308,6 +308,8 @@ static const struct serial8250_config uart_config[] = { .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01, .flags = UART_CAP_FIFO | UART_CAP_RTOIE, + .mcr_mask = ~UART_MCR_DTR, + .mcr_force = UART_MCR_DTR, }, [PORT_XR17D15X] = { .name = "XR17D15X", @@ -1229,6 +1231,10 @@ static void autoconfig(struct uart_8250_port *up, unsigned int probeflags) up->port.fifosize = uart_config[up->port.type].fifo_size; up->capabilities = uart_config[up->port.type].flags; up->tx_loadsz = uart_config[up->port.type].tx_loadsz; + if (!ALPHA_KLUDGE_MCR) { + up->mcr_mask = uart_config[up->port.type].mcr_mask; + up->mcr_force = uart_config[up->port.type].mcr_force; + } if (up->port.type == PORT_UNKNOWN) goto out; @@ -1987,6 +1993,10 @@ static int serial8250_startup(struct uart_port *port) up->port.fifosize = uart_config[up->port.type].fifo_size; up->tx_loadsz = uart_config[up->port.type].tx_loadsz; up->capabilities = uart_config[up->port.type].flags; + if (!ALPHA_KLUDGE_MCR) { + up->mcr_mask = uart_config[up->port.type].mcr_mask; + up->mcr_force = uart_config[up->port.type].mcr_force; + } up->mcr = 0; if (up->port.iotype != up->cur_iotype) @@ -2793,6 +2803,10 @@ serial8250_init_fixed_type_port(struct uart_8250_port *up, unsigned int type) up->port.fifosize = uart_config[type].fifo_size; up->capabilities = uart_config[type].flags; up->tx_loadsz = uart_config[type].tx_loadsz; + if (!ALPHA_KLUDGE_MCR) { + up->mcr_mask = uart_config[type].mcr_mask; + up->mcr_force = uart_config[type].mcr_force; + } } static void __init diff --git a/drivers/tty/serial/8250.h b/drivers/tty/serial/8250.h index 6edf4a6a22d4..1f7510051707 100644 --- a/drivers/tty/serial/8250.h +++ b/drivers/tty/serial/8250.h @@ -35,6 +35,8 @@ struct serial8250_config { unsigned short tx_loadsz; unsigned char fcr; unsigned int flags; + unsigned char mcr_mask; + unsigned char mcr_force; }; #define UART_CAP_FIFO (1 << 8) /* UART has FIFO */ From 604fdb75094a7367e1794fd0f62183380364ce13 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Thu, 10 Nov 2011 13:17:55 +0000 Subject: [PATCH 07/13] serial,mfd: Fix CMSPAR setup This is referenced the wrong way. Mika Westerberg added some checks to the tty to support multiple console, but the real problem is simply referencing the termios object via the wrong path. Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/mfd.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/tty/serial/mfd.c b/drivers/tty/serial/mfd.c index 286c386d9c46..e272d3919c67 100644 --- a/drivers/tty/serial/mfd.c +++ b/drivers/tty/serial/mfd.c @@ -884,7 +884,6 @@ serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios, { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); - struct tty_struct *tty = port->state->port.tty; unsigned char cval, fcr = 0; unsigned long flags; unsigned int baud, quot; @@ -907,8 +906,7 @@ serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios, } /* CMSPAR isn't supported by this driver */ - if (tty) - tty->termios->c_cflag &= ~CMSPAR; + termios->c_cflag &= ~CMSPAR; if (termios->c_cflag & CSTOPB) cval |= UART_LCR_STOP; From 90f04c2926cfb5bf74533b0a7766bc896f6a0c0e Mon Sep 17 00:00:00 2001 From: Tomoya MORINAGA Date: Fri, 11 Nov 2011 10:55:27 +0900 Subject: [PATCH 08/13] pch_uart: Fix DMA resource leak issue Changing UART mode PIO->DMA->PIO->DMA like below, pch_uart driver can't get DMA channel resource. setserial /dev/ttyPCH0 ^low_latency setserial /dev/ttyPCH0 low_latency CAUSE: Changing mode using setserial command, ".startup" function which gets DMA channel is called before ".verify_port" function which sets dma-flag(use_dma/use_dma_flag) as 1. PIO->DMA .startup: Since dma-flag is 0, DMA channel is not requested. .verify_port: dma-flag is set as 1. .shutdown: N/A DMA->PIO .startup: Since dma-flag is 1, DMA channel is requested. .verify_port: dma-flag is set as 0. .shutdown: Since dma-flag is 0, DMA channel is not released. This means DMA channel resource leak occurs. Next time, this driver can't get DMA channel resource forever. MODIFICATION: Currently, when release DMA channel resource, this driver checks dma-flag. However, this specification occurs the above issue. This driver must check whether dma_request_channel is executed or not. The values are saved in private data variable "chan_tx/chan_tx". These variables mean if the value is NULL, DMA channel is not requested, if not NULL, DMA channel is requested. This patch fixes the issue. Signed-off-by: Tomoya MORINAGA Acked-by: Alan Cox Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/pch_uart.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c index ac852b5a8f93..d6aba8c087e4 100644 --- a/drivers/tty/serial/pch_uart.c +++ b/drivers/tty/serial/pch_uart.c @@ -632,6 +632,7 @@ static void pch_request_dma(struct uart_port *port) dev_err(priv->port.dev, "%s:dma_request_channel FAILS(Rx)\n", __func__); dma_release_channel(priv->chan_tx); + priv->chan_tx = NULL; return; } @@ -1219,8 +1220,7 @@ static void pch_uart_shutdown(struct uart_port *port) dev_err(priv->port.dev, "pch_uart_hal_set_fifo Failed(ret=%d)\n", ret); - if (priv->use_dma_flag) - pch_free_dma(port); + pch_free_dma(port); free_irq(priv->port.irq, priv); } From 93f3350c46fa5dfcc9650eb19b186e71ffc924c3 Mon Sep 17 00:00:00 2001 From: Claudio Scordino Date: Wed, 9 Nov 2011 15:51:49 +0100 Subject: [PATCH 09/13] RS485: fix inconsistencies in the meaning of some variables The crisv10.c and the atmel_serial.c serial drivers intepret the fields of the serial_rs485 structure in a different way. In particular, crisv10.c uses SER_RS485_RTS_AFTER_SEND and SER_RS485_RTS_ON_SEND for the voltage of the RTS pin; atmel_serial.c, instead, uses these values to know if a delay must be set before and after sending. This patch makes the usage of these variables consistent across all drivers and fixes the Documentation as well. From now on, SER_RS485_RTS_AFTER_SEND and SER_RS485_RTS_ON_SEND will be used to set the voltage of the RTS pin (as in the crisv10.c driver); the delay will be understood by looking only at the value of delay_rts_before_send and delay_rts_after_send. Signed-off-by: Claudio Scordino Signed-off-by: Darron Black Acked-by: Jesper Nilsson Acked-by: Nicolas Ferre Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- Documentation/serial/serial-rs485.txt | 14 +++++++++++--- drivers/tty/serial/atmel_serial.c | 16 +++------------- drivers/tty/serial/crisv10.c | 10 ++-------- include/linux/serial.h | 14 ++++++++------ 4 files changed, 24 insertions(+), 30 deletions(-) diff --git a/Documentation/serial/serial-rs485.txt b/Documentation/serial/serial-rs485.txt index 079cb3df62cf..41c8378c0b2f 100644 --- a/Documentation/serial/serial-rs485.txt +++ b/Documentation/serial/serial-rs485.txt @@ -97,15 +97,23 @@ struct serial_rs485 rs485conf; - /* Set RS485 mode: */ + /* Enable RS485 mode: */ rs485conf.flags |= SER_RS485_ENABLED; + /* Set logical level for RTS pin equal to 1 when sending: */ + rs485conf.flags |= SER_RS485_RTS_ON_SEND; + /* or, set logical level for RTS pin equal to 0 when sending: */ + rs485conf.flags &= ~(SER_RS485_RTS_ON_SEND); + + /* Set logical level for RTS pin equal to 1 after sending: */ + rs485conf.flags |= SER_RS485_RTS_AFTER_SEND; + /* or, set logical level for RTS pin equal to 0 after sending: */ + rs485conf.flags &= ~(SER_RS485_RTS_AFTER_SEND); + /* Set rts delay before send, if needed: */ - rs485conf.flags |= SER_RS485_RTS_BEFORE_SEND; rs485conf.delay_rts_before_send = ...; /* Set rts delay after send, if needed: */ - rs485conf.flags |= SER_RS485_RTS_AFTER_SEND; rs485conf.delay_rts_after_send = ...; /* Set this flag if you want to receive data even whilst sending data */ diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 4a0f86fa1e90..4c823f341d98 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -228,7 +228,7 @@ void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf) if (rs485conf->flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); atmel_port->tx_done_mask = ATMEL_US_TXEMPTY; - if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND) + if ((rs485conf->delay_rts_after_send) > 0) UART_PUT_TTGR(port, rs485conf->delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; } else { @@ -304,7 +304,7 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl) if (atmel_port->rs485.flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); - if (atmel_port->rs485.flags & SER_RS485_RTS_AFTER_SEND) + if ((atmel_port->rs485.delay_rts_after_send) > 0) UART_PUT_TTGR(port, atmel_port->rs485.delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; @@ -1228,7 +1228,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, if (atmel_port->rs485.flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); - if (atmel_port->rs485.flags & SER_RS485_RTS_AFTER_SEND) + if ((atmel_port->rs485.delay_rts_after_send) > 0) UART_PUT_TTGR(port, atmel_port->rs485.delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; @@ -1447,16 +1447,6 @@ static void __devinit atmel_of_init_port(struct atmel_uart_port *atmel_port, rs485conf->delay_rts_after_send = rs485_delay[1]; rs485conf->flags = 0; - if (rs485conf->delay_rts_before_send == 0 && - rs485conf->delay_rts_after_send == 0) { - rs485conf->flags |= SER_RS485_RTS_ON_SEND; - } else { - if (rs485conf->delay_rts_before_send) - rs485conf->flags |= SER_RS485_RTS_BEFORE_SEND; - if (rs485conf->delay_rts_after_send) - rs485conf->flags |= SER_RS485_RTS_AFTER_SEND; - } - if (of_get_property(np, "rs485-rx-during-tx", NULL)) rs485conf->flags |= SER_RS485_RX_DURING_TX; diff --git a/drivers/tty/serial/crisv10.c b/drivers/tty/serial/crisv10.c index b7435043f2fe..1dfba7b779c8 100644 --- a/drivers/tty/serial/crisv10.c +++ b/drivers/tty/serial/crisv10.c @@ -3234,9 +3234,8 @@ rs_write(struct tty_struct *tty, e100_disable_rx(info); e100_enable_rx_irq(info); #endif - if ((info->rs485.flags & SER_RS485_RTS_BEFORE_SEND) && - (info->rs485.delay_rts_before_send > 0)) - msleep(info->rs485.delay_rts_before_send); + if (info->rs485.delay_rts_before_send > 0) + msleep(info->rs485.delay_rts_before_send); } #endif /* CONFIG_ETRAX_RS485 */ @@ -3693,10 +3692,6 @@ rs_ioctl(struct tty_struct *tty, rs485data.delay_rts_before_send = rs485ctrl.delay_rts_before_send; rs485data.flags = 0; - if (rs485data.delay_rts_before_send != 0) - rs485data.flags |= SER_RS485_RTS_BEFORE_SEND; - else - rs485data.flags &= ~(SER_RS485_RTS_BEFORE_SEND); if (rs485ctrl.enabled) rs485data.flags |= SER_RS485_ENABLED; @@ -4531,7 +4526,6 @@ static int __init rs_init(void) /* Set sane defaults */ info->rs485.flags &= ~(SER_RS485_RTS_ON_SEND); info->rs485.flags |= SER_RS485_RTS_AFTER_SEND; - info->rs485.flags &= ~(SER_RS485_RTS_BEFORE_SEND); info->rs485.delay_rts_before_send = 0; info->rs485.flags &= ~(SER_RS485_ENABLED); #endif diff --git a/include/linux/serial.h b/include/linux/serial.h index 97ff8e27a6cc..3d86517fe7d5 100644 --- a/include/linux/serial.h +++ b/include/linux/serial.h @@ -207,13 +207,15 @@ struct serial_icounter_struct { struct serial_rs485 { __u32 flags; /* RS485 feature flags */ -#define SER_RS485_ENABLED (1 << 0) -#define SER_RS485_RTS_ON_SEND (1 << 1) -#define SER_RS485_RTS_AFTER_SEND (1 << 2) -#define SER_RS485_RTS_BEFORE_SEND (1 << 3) +#define SER_RS485_ENABLED (1 << 0) /* If enabled */ +#define SER_RS485_RTS_ON_SEND (1 << 1) /* Logical level for + RTS pin when + sending */ +#define SER_RS485_RTS_AFTER_SEND (1 << 2) /* Logical level for + RTS pin after sent*/ #define SER_RS485_RX_DURING_TX (1 << 4) - __u32 delay_rts_before_send; /* Milliseconds */ - __u32 delay_rts_after_send; /* Milliseconds */ + __u32 delay_rts_before_send; /* Delay before send (milliseconds) */ + __u32 delay_rts_after_send; /* Delay after send (milliseconds) */ __u32 padding[5]; /* Memory is cheap, new structs are a royal PITA .. */ }; From 6edf0c9b1c26d047370cf2f35ff6bb3082243ec3 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 15 Nov 2011 16:01:09 -0800 Subject: [PATCH 10/13] Revert "tty/serial: Prevent drop of DCD on suspend for Tegra UARTs" This reverts commit 9636b755da7b498094bdf15b4ce9f6fd16995e4e. It wasn't supposed to be applied, thanks to Doug for letting me know. Cc: Doug Anderson Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250.c | 14 -------------- drivers/tty/serial/8250.h | 2 -- 2 files changed, 16 deletions(-) diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c index 2b0a4b63c5f7..eeadf1b8e093 100644 --- a/drivers/tty/serial/8250.c +++ b/drivers/tty/serial/8250.c @@ -308,8 +308,6 @@ static const struct serial8250_config uart_config[] = { .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01, .flags = UART_CAP_FIFO | UART_CAP_RTOIE, - .mcr_mask = ~UART_MCR_DTR, - .mcr_force = UART_MCR_DTR, }, [PORT_XR17D15X] = { .name = "XR17D15X", @@ -1231,10 +1229,6 @@ static void autoconfig(struct uart_8250_port *up, unsigned int probeflags) up->port.fifosize = uart_config[up->port.type].fifo_size; up->capabilities = uart_config[up->port.type].flags; up->tx_loadsz = uart_config[up->port.type].tx_loadsz; - if (!ALPHA_KLUDGE_MCR) { - up->mcr_mask = uart_config[up->port.type].mcr_mask; - up->mcr_force = uart_config[up->port.type].mcr_force; - } if (up->port.type == PORT_UNKNOWN) goto out; @@ -1993,10 +1987,6 @@ static int serial8250_startup(struct uart_port *port) up->port.fifosize = uart_config[up->port.type].fifo_size; up->tx_loadsz = uart_config[up->port.type].tx_loadsz; up->capabilities = uart_config[up->port.type].flags; - if (!ALPHA_KLUDGE_MCR) { - up->mcr_mask = uart_config[up->port.type].mcr_mask; - up->mcr_force = uart_config[up->port.type].mcr_force; - } up->mcr = 0; if (up->port.iotype != up->cur_iotype) @@ -2803,10 +2793,6 @@ serial8250_init_fixed_type_port(struct uart_8250_port *up, unsigned int type) up->port.fifosize = uart_config[type].fifo_size; up->capabilities = uart_config[type].flags; up->tx_loadsz = uart_config[type].tx_loadsz; - if (!ALPHA_KLUDGE_MCR) { - up->mcr_mask = uart_config[type].mcr_mask; - up->mcr_force = uart_config[type].mcr_force; - } } static void __init diff --git a/drivers/tty/serial/8250.h b/drivers/tty/serial/8250.h index 1f7510051707..6edf4a6a22d4 100644 --- a/drivers/tty/serial/8250.h +++ b/drivers/tty/serial/8250.h @@ -35,8 +35,6 @@ struct serial8250_config { unsigned short tx_loadsz; unsigned char fcr; unsigned int flags; - unsigned char mcr_mask; - unsigned char mcr_force; }; #define UART_CAP_FIFO (1 << 8) /* UART has FIFO */ From df92d0561de364de53c42abc5d43e04ab6f326a5 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Wed, 16 Nov 2011 16:27:07 +0100 Subject: [PATCH 11/13] TTY: ldisc, allow waiting for ldisc arbitrarily long To fix a nasty bug in ldisc hup vs. reinit we need to wait infinitely long for ldisc to be gone. So here we add a parameter to tty_ldisc_wait_idle to allow that. This is only a preparation for the real fix which is done in the following patches. Signed-off-by: Jiri Slaby Cc: Dave Young Cc: Dave Jones Cc: Ben Hutchings Cc: Dmitriy Matrosov Cc: Alan Cox Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_ldisc.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 512c49f98e85..534d176a78ed 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -547,15 +547,16 @@ static void tty_ldisc_flush_works(struct tty_struct *tty) /** * tty_ldisc_wait_idle - wait for the ldisc to become idle * @tty: tty to wait for + * @timeout: for how long to wait at most * * Wait for the line discipline to become idle. The discipline must * have been halted for this to guarantee it remains idle. */ -static int tty_ldisc_wait_idle(struct tty_struct *tty) +static int tty_ldisc_wait_idle(struct tty_struct *tty, long timeout) { - int ret; + long ret; ret = wait_event_timeout(tty_ldisc_idle, - atomic_read(&tty->ldisc->users) == 1, 5 * HZ); + atomic_read(&tty->ldisc->users) == 1, timeout); if (ret < 0) return ret; return ret > 0 ? 0 : -EBUSY; @@ -665,7 +666,7 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) tty_ldisc_flush_works(tty); - retval = tty_ldisc_wait_idle(tty); + retval = tty_ldisc_wait_idle(tty, 5 * HZ); tty_lock(); mutex_lock(&tty->ldisc_mutex); @@ -762,7 +763,7 @@ static int tty_ldisc_reinit(struct tty_struct *tty, int ldisc) if (IS_ERR(ld)) return -1; - WARN_ON_ONCE(tty_ldisc_wait_idle(tty)); + WARN_ON_ONCE(tty_ldisc_wait_idle(tty, 5 * HZ)); tty_ldisc_close(tty, tty->ldisc); tty_ldisc_put(tty->ldisc); From 300420722e0734a4254f3b634e0f82664495d210 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Wed, 16 Nov 2011 16:27:08 +0100 Subject: [PATCH 12/13] TTY: ldisc, move wait idle to caller It is the only place where reinit is called from. And we really need to wait for the old ldisc to go once. Actually this is the place where the waiting originally was (before removed and re-added later). This will make the fix in the following patch easier to implement. Signed-off-by: Jiri Slaby Cc: Dave Young Cc: Dave Jones Cc: Ben Hutchings Cc: Dmitriy Matrosov Cc: Alan Cox Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_ldisc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 534d176a78ed..a69a755035b6 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -763,8 +763,6 @@ static int tty_ldisc_reinit(struct tty_struct *tty, int ldisc) if (IS_ERR(ld)) return -1; - WARN_ON_ONCE(tty_ldisc_wait_idle(tty, 5 * HZ)); - tty_ldisc_close(tty, tty->ldisc); tty_ldisc_put(tty->ldisc); tty->ldisc = NULL; @@ -848,6 +846,8 @@ void tty_ldisc_hangup(struct tty_struct *tty) it means auditing a lot of other paths so this is a FIXME */ if (tty->ldisc) { /* Not yet closed */ + WARN_ON_ONCE(tty_ldisc_wait_idle(tty, 5 * HZ)); + if (reset == 0) { if (!tty_ldisc_reinit(tty, tty->termios->c_line)) From 0c73c08ec73dbe080b9ec56696ee21d32754d918 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Wed, 16 Nov 2011 16:27:09 +0100 Subject: [PATCH 13/13] TTY: ldisc, wait for ldisc infinitely in hangup For /dev/console case, we do not kill all ldisc users. It's due to redirected_tty_write test in __tty_hangup. In that case there still might be a process waiting e.g. in n_tty_read for input. We wait for such processes to disappear. The problem is that we use a timeout. After this timeout, we continue closing the ldisc and start freeing tty resources. It obviously leads to crashes when the other process is woken. So to fix this, we wait infinitely before reiniting the ldisc. (The tiocsetd remains untouched -- times out after 5s.) This is nicely reproducible with this run from shell: exec 0<>/dev/console 1<>/dev/console 2<>/dev/console and stopping a getty like: systemctl stop serial-getty@ttyS0.service The crash proper may be produced only under load or with constified timing the same as for 92f6fa09b. Signed-off-by: Jiri Slaby Cc: Dave Young Cc: Dave Jones Cc: Ben Hutchings Cc: Dmitriy Matrosov Cc: Alan Cox Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_ldisc.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index a69a755035b6..8e0924f55446 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -36,6 +36,7 @@ #include #include +#include /* * This guards the refcounted line discipline lists. The lock @@ -837,7 +838,7 @@ void tty_ldisc_hangup(struct tty_struct *tty) tty_unlock(); cancel_work_sync(&tty->buf.work); mutex_unlock(&tty->ldisc_mutex); - +retry: tty_lock(); mutex_lock(&tty->ldisc_mutex); @@ -846,7 +847,21 @@ void tty_ldisc_hangup(struct tty_struct *tty) it means auditing a lot of other paths so this is a FIXME */ if (tty->ldisc) { /* Not yet closed */ - WARN_ON_ONCE(tty_ldisc_wait_idle(tty, 5 * HZ)); + if (atomic_read(&tty->ldisc->users) != 1) { + char cur_n[TASK_COMM_LEN], tty_n[64]; + long timeout = 3 * HZ; + tty_unlock(); + + while (tty_ldisc_wait_idle(tty, timeout) == -EBUSY) { + timeout = MAX_SCHEDULE_TIMEOUT; + printk_ratelimited(KERN_WARNING + "%s: waiting (%s) for %s took too long, but we keep waiting...\n", + __func__, get_task_comm(cur_n, current), + tty_name(tty, tty_n)); + } + mutex_unlock(&tty->ldisc_mutex); + goto retry; + } if (reset == 0) {