From 045f32dda9477d3ddf31a4fa862c487d0f747e33 Mon Sep 17 00:00:00 2001 From: Baruch Siach Date: Mon, 16 Feb 2015 08:27:49 +0200 Subject: [PATCH 01/16] Revert "tty/serial: of_serial: add DT alias ID handling" This reverts commit 6d01bb9dc82a60580f749062a48cb47cd5caca07. The exact same code was added in commit 3239fd31d4 (serial: of-serial: fetch line number from DT) a few lined above. Doing this once should be enough. Cc: Rob Herring Signed-off-by: Baruch Siach Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/of_serial.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c index 7ff61e24a195cb..33fb94f7896773 100644 --- a/drivers/tty/serial/of_serial.c +++ b/drivers/tty/serial/of_serial.c @@ -133,10 +133,6 @@ static int of_platform_serial_setup(struct platform_device *ofdev, if (of_find_property(np, "no-loopback-test", NULL)) port->flags |= UPF_SKIP_TEST; - ret = of_alias_get_id(np, "serial"); - if (ret >= 0) - port->line = ret; - port->dev = &ofdev->dev; switch (type) { From ca8bb4aefb932e3da105f28cbfba36d57a931081 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Sun, 15 Feb 2015 18:32:16 +0100 Subject: [PATCH 02/16] serial: 8250: Revert "tty: serial: 8250_core: read only RX if there is something in the FIFO" This reverts commit 0aa525d11859c1a4d5b78fdc704148e2ae03ae13. The conditional RX-FIFO read seems to cause spurious interrupts and we see just: |serial8250: too much work for irq29 The previous behaviour was "default" for decades and Marvell's 88f6282 SoC might not be the only that relies on it. Therefore the Omap fix is reverted for now. Fixes: 0aa525d11859 ("tty: serial: 8250_core: read only RX if there is something in the FIFO") Reported-By: Nicolas Schichan Debuged-By: Peter Hurley Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_core.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index e3b9570a1eff8a..deae122c9c4bac 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -2138,8 +2138,8 @@ int serial8250_do_startup(struct uart_port *port) /* * Clear the interrupt registers. */ - if (serial_port_in(port, UART_LSR) & UART_LSR_DR) - serial_port_in(port, UART_RX); + serial_port_in(port, UART_LSR); + serial_port_in(port, UART_RX); serial_port_in(port, UART_IIR); serial_port_in(port, UART_MSR); @@ -2300,8 +2300,8 @@ int serial8250_do_startup(struct uart_port *port) * saved flags to avoid getting false values from polling * routines or the previous session. */ - if (serial_port_in(port, UART_LSR) & UART_LSR_DR) - serial_port_in(port, UART_RX); + serial_port_in(port, UART_LSR); + serial_port_in(port, UART_RX); serial_port_in(port, UART_IIR); serial_port_in(port, UART_MSR); up->lsr_saved_flags = 0; @@ -2394,8 +2394,7 @@ void serial8250_do_shutdown(struct uart_port *port) * Read data port to reset things, and then unlink from * the IRQ chain. */ - if (serial_port_in(port, UART_LSR) & UART_LSR_DR) - serial_port_in(port, UART_RX); + serial_port_in(port, UART_RX); serial8250_rpm_put(up); del_timer_sync(&up->timer); From f2e0ea861117bda073d1d7ffbd3120c07c0d5d34 Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 6 Mar 2015 10:49:21 +0000 Subject: [PATCH 03/16] Change email address for 8250_pci I'm still receiving reports to my email address, so let's point this at the linux-serial mailing list instead. Cc: Signed-off-by: Russell King Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c index daf2c82984e95d..65dd3ad442ea72 100644 --- a/drivers/tty/serial/8250/8250_pci.c +++ b/drivers/tty/serial/8250/8250_pci.c @@ -69,7 +69,7 @@ static void moan_device(const char *str, struct pci_dev *dev) "Please send the output of lspci -vv, this\n" "message (0x%04x,0x%04x,0x%04x,0x%04x), the\n" "manufacturer and name of serial board or\n" - "modem board to rmk+serial@arm.linux.org.uk.\n", + "modem board to .\n", pci_name(dev), str, dev->vendor, dev->device, dev->subsystem_vendor, dev->subsystem_device); } From 6262a3692b921a82075695c5c6d10f4a6bcc5fac Mon Sep 17 00:00:00 2001 From: Wang YanQing Date: Sat, 7 Mar 2015 01:13:03 +0800 Subject: [PATCH 04/16] serial:8250:8250_pci: fix redundant entry report for WCH_CH352_2S Commit 8b5c913f7ee6464849570bacb6bcd9ef0eaf7dce ("serial: 8250_pci: Add WCH CH352 quirk to avoid Xscale detection") trigger one redundant entry report message. This patch fix it. Reported-by: Russell King Signed-off-by: Wang YanQing Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_pci.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c index 65dd3ad442ea72..285b875fd18763 100644 --- a/drivers/tty/serial/8250/8250_pci.c +++ b/drivers/tty/serial/8250/8250_pci.c @@ -5415,10 +5415,6 @@ static struct pci_device_id serial_pci_tbl[] = { PCI_ANY_ID, PCI_ANY_ID, 0, 0, pbn_b0_bt_2_115200 }, - { PCI_VENDOR_ID_WCH, PCI_DEVICE_ID_WCH_CH352_2S, - PCI_ANY_ID, PCI_ANY_ID, - 0, 0, pbn_b0_bt_2_115200 }, - { PCIE_VENDOR_ID_WCH, PCIE_DEVICE_ID_WCH_CH384_4S, PCI_ANY_ID, PCI_ANY_ID, 0, 0, pbn_wch384_4 }, From 7cf91108d44dbef3d48766fd0e7f7347c2e48bda Mon Sep 17 00:00:00 2001 From: Wang YanQing Date: Sat, 7 Mar 2015 01:08:35 +0800 Subject: [PATCH 05/16] serial:8250:8250_pci: delete unneeded quirk entries These quirk entries have the same effect as default quirk entry, so we can just delete them. Signed-off-by: Wang YanQing Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_pci.c | 14 -------------- 1 file changed, 14 deletions(-) diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c index 285b875fd18763..892eb32cdef4bd 100644 --- a/drivers/tty/serial/8250/8250_pci.c +++ b/drivers/tty/serial/8250/8250_pci.c @@ -1987,13 +1987,6 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = { .subdevice = PCI_ANY_ID, .setup = byt_serial_setup, }, - { - .vendor = PCI_VENDOR_ID_INTEL, - .device = PCI_DEVICE_ID_INTEL_QRK_UART, - .subvendor = PCI_ANY_ID, - .subdevice = PCI_ANY_ID, - .setup = pci_default_setup, - }, { .vendor = PCI_VENDOR_ID_INTEL, .device = PCI_DEVICE_ID_INTEL_BSW_UART1, @@ -2199,13 +2192,6 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = { /* * PLX */ - { - .vendor = PCI_VENDOR_ID_PLX, - .device = PCI_DEVICE_ID_PLX_9030, - .subvendor = PCI_SUBVENDOR_ID_PERLE, - .subdevice = PCI_ANY_ID, - .setup = pci_default_setup, - }, { .vendor = PCI_VENDOR_ID_PLX, .device = PCI_DEVICE_ID_PLX_9050, From dfd37668ea6d5029fb5d8a66ea5e202d0655fad7 Mon Sep 17 00:00:00 2001 From: Desmond Liu Date: Thu, 26 Feb 2015 16:35:57 -0800 Subject: [PATCH 06/16] serial: 8250_dw: Fix get_mctrl behaviour Fixed behaviour of get_mctrl() serial driver function as documented in: https://www.kernel.org/doc/Documentation/serial/driver Added device-tree properties 'dcd-override', 'dsr-override', 'cts-override', and 'ri-override' specific to the Synopsis 8250 DesignWare UART driver. Allows one to force Data Carrier Detect, Clear To Send, and Data Set Ready signals to permanently be reported as active. The Ring indicator can be forced to be reported as inactive. It is possible that if modem control signalling is enabled on a port that doesn't have these pins (e.g. - a simple two wire Tx/Rx port), the driver can hang indefinitely waiting for the state to change. The new DT properties allow the driver to ignore the state of these pins on serial ports that don't support them, as recommended in the kernel documentation. Reviewed-by: JD (Jiandong) Zheng Signed-off-by: Jonathan Richardson Signed-off-by: Greg Kroah-Hartman --- .../bindings/serial/snps-dw-apb-uart.txt | 16 ++++++++++ drivers/tty/serial/8250/8250_dw.c | 32 +++++++++++++++++++ 2 files changed, 48 insertions(+) diff --git a/Documentation/devicetree/bindings/serial/snps-dw-apb-uart.txt b/Documentation/devicetree/bindings/serial/snps-dw-apb-uart.txt index 7f76214f728aa6..289c40ed747042 100644 --- a/Documentation/devicetree/bindings/serial/snps-dw-apb-uart.txt +++ b/Documentation/devicetree/bindings/serial/snps-dw-apb-uart.txt @@ -21,6 +21,18 @@ Optional properties: - reg-io-width : the size (in bytes) of the IO accesses that should be performed on the device. If this property is not present then single byte accesses are used. +- dcd-override : Override the DCD modem status signal. This signal will always + be reported as active instead of being obtained from the modem status + register. Define this if your serial port does not use this pin. +- dsr-override : Override the DTS modem status signal. This signal will always + be reported as active instead of being obtained from the modem status + register. Define this if your serial port does not use this pin. +- cts-override : Override the CTS modem status signal. This signal will always + be reported as active instead of being obtained from the modem status + register. Define this if your serial port does not use this pin. +- ri-override : Override the RI modem status signal. This signal will always be + reported as inactive instead of being obtained from the modem status register. + Define this if your serial port does not use this pin. Example: @@ -31,6 +43,10 @@ Example: interrupts = <10>; reg-shift = <2>; reg-io-width = <4>; + dcd-override; + dsr-override; + cts-override; + ri-override; }; Example with one clock: diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c index e6011623583649..2ab229ddee389e 100644 --- a/drivers/tty/serial/8250/8250_dw.c +++ b/drivers/tty/serial/8250/8250_dw.c @@ -59,6 +59,8 @@ struct dw8250_data { u8 usr_reg; int last_mcr; int line; + int msr_mask_on; + int msr_mask_off; struct clk *clk; struct clk *pclk; struct reset_control *rst; @@ -81,6 +83,12 @@ static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value) value &= ~UART_MSR_DCTS; } + /* Override any modem control signals if needed */ + if (offset == UART_MSR) { + value |= d->msr_mask_on; + value &= ~d->msr_mask_off; + } + return value; } @@ -334,6 +342,30 @@ static int dw8250_probe_of(struct uart_port *p, if (id >= 0) p->line = id; + if (of_property_read_bool(np, "dcd-override")) { + /* Always report DCD as active */ + data->msr_mask_on |= UART_MSR_DCD; + data->msr_mask_off |= UART_MSR_DDCD; + } + + if (of_property_read_bool(np, "dsr-override")) { + /* Always report DSR as active */ + data->msr_mask_on |= UART_MSR_DSR; + data->msr_mask_off |= UART_MSR_DDSR; + } + + if (of_property_read_bool(np, "cts-override")) { + /* Always report DSR as active */ + data->msr_mask_on |= UART_MSR_DSR; + data->msr_mask_off |= UART_MSR_DDSR; + } + + if (of_property_read_bool(np, "ri-override")) { + /* Always report Ring indicator as inactive */ + data->msr_mask_off |= UART_MSR_RI; + data->msr_mask_off |= UART_MSR_TERI; + } + /* clock got configured through clk api, all done */ if (p->uartclk) return 0; From f0bf0bd07943bfde8f5ac39a32664810a379c7d3 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Fri, 27 Feb 2015 18:40:31 +0100 Subject: [PATCH 07/16] tty: fix up atime/mtime mess, take four This problem was taken care of three times already in * b0de59b5733d18b0d1974a060860a8b5c1b36a2e (TTY: do not update atime/mtime on read/write), * 37b7f3c76595e23257f61bd80b223de8658617ee (TTY: fix atime/mtime regression), and * b0b885657b6c8ef63a46bc9299b2a7715d19acde (tty: fix up atime/mtime mess, take three) But it still misses one point. As John Paul correctly points out, we do not care about setting date. If somebody ever changes wall time backwards (by mistake for example), tty timestamps are never updated until the original wall time passes. So check the absolute difference of times and if it large than "8 seconds or so", always update the time. That means we will update immediatelly when changing time. Ergo, CAP_SYS_TIME can foul the check, but it was always that way. Thanks John for serving me this so nicely debugged. Signed-off-by: Jiri Slaby Reported-by: John Paul Perry Cc: # all, as b0b885657 was backported Acked-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_io.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 51f066aa375e64..2bb4dfc0287340 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -1028,8 +1028,8 @@ EXPORT_SYMBOL(start_tty); /* We limit tty time update visibility to every 8 seconds or so. */ static void tty_update_time(struct timespec *time) { - unsigned long sec = get_seconds() & ~7; - if ((long)(sec - time->tv_sec) > 0) + unsigned long sec = get_seconds(); + if (abs(sec - time->tv_sec) & ~7) time->tv_sec = sec; } From 30a22c215a0007603ffc08021f2e8b64018517dd Mon Sep 17 00:00:00 2001 From: Peter Hurley Date: Sun, 1 Mar 2015 10:11:05 -0500 Subject: [PATCH 08/16] console: Fix console name size mismatch commit 6ae9200f2cab7 ("enlarge console.name") increased the storage for the console name to 16 bytes, but not the corresponding struct console_cmdline::name storage. Console names longer than 8 bytes cause read beyond end-of-string and failure to match console; I'm not sure if there are other unexpected consequences. Cc: # 2.6.22+ Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- kernel/printk/console_cmdline.h | 2 +- kernel/printk/printk.c | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/printk/console_cmdline.h b/kernel/printk/console_cmdline.h index cbd69d84234117..2ca4a8b5fe5796 100644 --- a/kernel/printk/console_cmdline.h +++ b/kernel/printk/console_cmdline.h @@ -3,7 +3,7 @@ struct console_cmdline { - char name[8]; /* Name of the driver */ + char name[16]; /* Name of the driver */ int index; /* Minor dev. to use */ char *options; /* Options for the driver */ #ifdef CONFIG_A11Y_BRAILLE_CONSOLE diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 01cfd69c54c677..bb0635bd74f26a 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2464,6 +2464,7 @@ void register_console(struct console *newcon) for (i = 0, c = console_cmdline; i < MAX_CMDLINECONSOLES && c->name[0]; i++, c++) { + BUILD_BUG_ON(sizeof(c->name) != sizeof(newcon->name)); if (strcmp(c->name, newcon->name) != 0) continue; if (newcon->index >= 0 && From c4e6dcfa00dab9b10e75bba835393b81f256310b Mon Sep 17 00:00:00 2001 From: Axel Lin Date: Mon, 16 Feb 2015 22:39:04 +0800 Subject: [PATCH 09/16] serial: sprd: Fix missing spin_unlock in sprd_handle_irq() Fix return from sprd_handle_irq() with spin_lock held. Signed-off-by: Axel Lin Reviewed-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sprd_serial.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c index 594b63331ef40e..bca975f5093b73 100644 --- a/drivers/tty/serial/sprd_serial.c +++ b/drivers/tty/serial/sprd_serial.c @@ -293,8 +293,10 @@ static irqreturn_t sprd_handle_irq(int irq, void *dev_id) ims = serial_in(port, SPRD_IMSR); - if (!ims) + if (!ims) { + spin_unlock(&port->lock); return IRQ_NONE; + } serial_out(port, SPRD_ICLR, ~0); From 2bb785169e9709d41220e5c18b0270883a82f85c Mon Sep 17 00:00:00 2001 From: Peter Hurley Date: Sun, 1 Mar 2015 10:18:16 -0500 Subject: [PATCH 10/16] serial: core: Fix iotype userspace breakage commit 3ffb1a8193bea ("serial: core: Add big-endian iotype") re-numbered userspace-dependent values; ioctl(TIOCSSERIAL) can assign the port iotype (which is expected to match the selected i/o accessors), so iotype values must not be changed. Cc: Kevin Cernekee Cc: # 3.19+ Signed-off-by: Peter Hurley Reviewed-by: Kevin Cernekee Signed-off-by: Greg Kroah-Hartman --- include/linux/serial_core.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index baf3e1d08416fa..1094f2d9cadbe9 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -147,9 +147,9 @@ struct uart_port { #define UPIO_HUB6 (1) /* Hub6 ISA card */ #define UPIO_MEM (2) /* 8b MMIO access */ #define UPIO_MEM32 (3) /* 32b little endian */ -#define UPIO_MEM32BE (4) /* 32b big endian */ -#define UPIO_AU (5) /* Au1x00 and RT288x type IO */ -#define UPIO_TSI (6) /* Tsi108/109 type IO */ +#define UPIO_AU (4) /* Au1x00 and RT288x type IO */ +#define UPIO_TSI (5) /* Tsi108/109 type IO */ +#define UPIO_MEM32BE (6) /* 32b big endian */ unsigned int read_status_mask; /* driver specific */ unsigned int ignore_status_mask; /* driver specific */ From 647f162b8e7e446c4bade031eb8a1a0a83d3de82 Mon Sep 17 00:00:00 2001 From: Peter Hurley Date: Sun, 1 Mar 2015 10:24:28 -0500 Subject: [PATCH 11/16] serial: uapi: Declare all userspace-visible io types ioctl(TIOCGSERIAL|TIOCSSERIAL) report and can change the port->iotype. UART drivers use the UPIO_* definitions, but the uapi header defines parallel values and userspace uses these parallel values for ioctls; thus the userspace values are definitive. Define UPIO_* iotypes in terms of the uapi defines, SERIAL_IO_*; extend the uapi defines to include all values in use by the serial core. Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- include/linux/serial_core.h | 14 +++++++------- include/uapi/linux/serial.h | 4 ++++ 2 files changed, 11 insertions(+), 7 deletions(-) diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 1094f2d9cadbe9..d10965f0d8a4af 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -143,13 +143,13 @@ struct uart_port { unsigned char iotype; /* io access style */ unsigned char unused1; -#define UPIO_PORT (0) /* 8b I/O port access */ -#define UPIO_HUB6 (1) /* Hub6 ISA card */ -#define UPIO_MEM (2) /* 8b MMIO access */ -#define UPIO_MEM32 (3) /* 32b little endian */ -#define UPIO_AU (4) /* Au1x00 and RT288x type IO */ -#define UPIO_TSI (5) /* Tsi108/109 type IO */ -#define UPIO_MEM32BE (6) /* 32b big endian */ +#define UPIO_PORT (SERIAL_IO_PORT) /* 8b I/O port access */ +#define UPIO_HUB6 (SERIAL_IO_HUB6) /* Hub6 ISA card */ +#define UPIO_MEM (SERIAL_IO_MEM) /* 8b MMIO access */ +#define UPIO_MEM32 (SERIAL_IO_MEM32) /* 32b little endian */ +#define UPIO_AU (SERIAL_IO_AU) /* Au1x00 and RT288x type IO */ +#define UPIO_TSI (SERIAL_IO_TSI) /* Tsi108/109 type IO */ +#define UPIO_MEM32BE (SERIAL_IO_MEM32BE) /* 32b big endian */ unsigned int read_status_mask; /* driver specific */ unsigned int ignore_status_mask; /* driver specific */ diff --git a/include/uapi/linux/serial.h b/include/uapi/linux/serial.h index 5e0d0ed61cf3b7..25331f9faa7682 100644 --- a/include/uapi/linux/serial.h +++ b/include/uapi/linux/serial.h @@ -65,6 +65,10 @@ struct serial_struct { #define SERIAL_IO_PORT 0 #define SERIAL_IO_HUB6 1 #define SERIAL_IO_MEM 2 +#define SERIAL_IO_MEM32 3 +#define SERIAL_IO_AU 4 +#define SERIAL_IO_TSI 5 +#define SERIAL_IO_MEM32BE 6 #define UART_CLEAR_FIFO 0x01 #define UART_USE_FIFO 0x02 From 2c3fbe3cf28fbd7001545a92a83b4f8acfd9fa36 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 4 Mar 2015 10:39:03 +0100 Subject: [PATCH 12/16] net: irda: fix wait_until_sent poll timeout In case an infinite timeout (0) is requested, the irda wait_until_sent implementation would use a zero poll timeout rather than the default 200ms. Note that wait_until_sent is currently never called with a 0-timeout argument due to a bug in tty_wait_until_sent. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable # v2.6.12 Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- net/irda/ircomm/ircomm_tty.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/irda/ircomm/ircomm_tty.c b/net/irda/ircomm/ircomm_tty.c index 40695b9751c10b..4efe486baee62f 100644 --- a/net/irda/ircomm/ircomm_tty.c +++ b/net/irda/ircomm/ircomm_tty.c @@ -798,7 +798,9 @@ static void ircomm_tty_wait_until_sent(struct tty_struct *tty, int timeout) orig_jiffies = jiffies; /* Set poll time to 200 ms */ - poll_time = IRDA_MIN(timeout, msecs_to_jiffies(200)); + poll_time = msecs_to_jiffies(200); + if (timeout) + poll_time = min_t(unsigned long, timeout, poll_time); spin_lock_irqsave(&self->spinlock, flags); while (self->tx_skb && self->tx_skb->len) { From 6b270fd4db08fc13683d616a733d9cacdd3b4afa Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 4 Mar 2015 10:39:04 +0100 Subject: [PATCH 13/16] TTY: bfin_jtag_comm: remove incorrect wait_until_sent operation Remove incorrect and redundant wait_until_sent operation, which waits for the driver buffer rather than any hardware buffers to drain, something which is already taken care of by the tty layer (and chars_in_buffer). Signed-off-by: Johan Hovold Reviewed-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/bfin_jtag_comm.c | 13 ------------- 1 file changed, 13 deletions(-) diff --git a/drivers/tty/bfin_jtag_comm.c b/drivers/tty/bfin_jtag_comm.c index d7b198c400c755..ce24182f851479 100644 --- a/drivers/tty/bfin_jtag_comm.c +++ b/drivers/tty/bfin_jtag_comm.c @@ -210,18 +210,6 @@ bfin_jc_chars_in_buffer(struct tty_struct *tty) return circ_cnt(&bfin_jc_write_buf); } -static void -bfin_jc_wait_until_sent(struct tty_struct *tty, int timeout) -{ - unsigned long expire = jiffies + timeout; - while (!circ_empty(&bfin_jc_write_buf)) { - if (signal_pending(current)) - break; - if (time_after(jiffies, expire)) - break; - } -} - static const struct tty_operations bfin_jc_ops = { .open = bfin_jc_open, .close = bfin_jc_close, @@ -230,7 +218,6 @@ static const struct tty_operations bfin_jc_ops = { .flush_chars = bfin_jc_flush_chars, .write_room = bfin_jc_write_room, .chars_in_buffer = bfin_jc_chars_in_buffer, - .wait_until_sent = bfin_jc_wait_until_sent, }; static int __init bfin_jc_init(void) From f528bf4f57e43d1af4b2a5c97f09e43e0338c105 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 4 Mar 2015 10:39:05 +0100 Subject: [PATCH 14/16] USB: serial: fix infinite wait_until_sent timeout Make sure to handle an infinite timeout (0). Note that wait_until_sent is currently never called with a 0-timeout argument due to a bug in tty_wait_until_sent. Fixes: dcf010503966 ("USB: serial: add generic wait_until_sent implementation") Cc: stable # v3.10 Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/generic.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c index ccf1df7c4b80f3..54e170dd3dad0c 100644 --- a/drivers/usb/serial/generic.c +++ b/drivers/usb/serial/generic.c @@ -258,7 +258,8 @@ void usb_serial_generic_wait_until_sent(struct tty_struct *tty, long timeout) * character or at least one jiffy. */ period = max_t(unsigned long, (10 * HZ / bps), 1); - period = min_t(unsigned long, period, timeout); + if (timeout) + period = min_t(unsigned long, period, timeout); dev_dbg(&port->dev, "%s - timeout = %u ms, period = %u ms\n", __func__, jiffies_to_msecs(timeout), @@ -268,7 +269,7 @@ void usb_serial_generic_wait_until_sent(struct tty_struct *tty, long timeout) schedule_timeout_interruptible(period); if (signal_pending(current)) break; - if (time_after(jiffies, expire)) + if (timeout && time_after(jiffies, expire)) break; } } From 79fbf4a550ed6a22e1ae1516113e6c7fa5d56a53 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 4 Mar 2015 10:39:06 +0100 Subject: [PATCH 15/16] TTY: fix tty_wait_until_sent on 64-bit machines Fix overflow bug in tty_wait_until_sent on 64-bit machines, where an infinite timeout (0) would be passed to the underlying tty-driver's wait_until_sent-operation as a negative timeout (-1), causing it to return immediately. This manifests itself for example as tcdrain() returning immediately, drivers not honouring the drain flags when setting terminal attributes, or even dropped data on close as a requested infinite closing-wait timeout would be ignored. The first symptom was reported by Asier LLANO who noted that tcdrain() returned prematurely when using the ftdi_sio usb-serial driver. Fix this by passing 0 rather than MAX_SCHEDULE_TIMEOUT (LONG_MAX) to the underlying tty driver. Note that the serial-core wait_until_sent-implementation is not affected by this bug due to a lucky chance (comparison to an unsigned maximum timeout), and neither is the cyclades one that had an explicit check for negative timeouts, but all other tty drivers appear to be affected. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable # v2.6.12 Reported-by: ZIV-Asier Llano Palacios Signed-off-by: Johan Hovold Reviewed-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_ioctl.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c index a5cf253b2544f0..89ae23ac9ae61c 100644 --- a/drivers/tty/tty_ioctl.c +++ b/drivers/tty/tty_ioctl.c @@ -217,11 +217,17 @@ void tty_wait_until_sent(struct tty_struct *tty, long timeout) #endif if (!timeout) timeout = MAX_SCHEDULE_TIMEOUT; + if (wait_event_interruptible_timeout(tty->write_wait, - !tty_chars_in_buffer(tty), timeout) >= 0) { - if (tty->ops->wait_until_sent) - tty->ops->wait_until_sent(tty, timeout); + !tty_chars_in_buffer(tty), timeout) < 0) { + return; } + + if (timeout == MAX_SCHEDULE_TIMEOUT) + timeout = 0; + + if (tty->ops->wait_until_sent) + tty->ops->wait_until_sent(tty, timeout); } EXPORT_SYMBOL(tty_wait_until_sent); From c37bc682e30b8027054356214eb8a3aafbda8e37 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 4 Mar 2015 10:39:07 +0100 Subject: [PATCH 16/16] TTY: fix tty_wait_until_sent maximum timeout Currently tty_wait_until_sent may take up to twice as long as the requested timeout while waiting for driver and hardware buffers to drain. Fix this by taking the remaining number of jiffies after waiting for driver buffers to drain into account so that the timeout actually becomes a maximum timeout as it is documented to be. Note that this specifically implies tighter timings when closing a port as a consequence of actually honouring the port closing-wait setting for drivers relying on tty_wait_until_sent_from_close (e.g. via tty_port_close_start). Signed-off-by: Johan Hovold Reviewed-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_ioctl.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c index 89ae23ac9ae61c..632fc815206169 100644 --- a/drivers/tty/tty_ioctl.c +++ b/drivers/tty/tty_ioctl.c @@ -218,10 +218,10 @@ void tty_wait_until_sent(struct tty_struct *tty, long timeout) if (!timeout) timeout = MAX_SCHEDULE_TIMEOUT; - if (wait_event_interruptible_timeout(tty->write_wait, - !tty_chars_in_buffer(tty), timeout) < 0) { + timeout = wait_event_interruptible_timeout(tty->write_wait, + !tty_chars_in_buffer(tty), timeout); + if (timeout <= 0) return; - } if (timeout == MAX_SCHEDULE_TIMEOUT) timeout = 0;