On Sat, Oct 29, 2011 at 1:04 AM, Javier Martinez Canillas <martinez.javier@xxxxxxxxx> wrote: > This patch adds TIA/EIA-485 standard support to OMAP-UART controller driver > by adding handlers for TIOCSRS485 and TIOCGRS485 ioctl commands. > > This patch is based on Ilya Yanok <yanok@xxxxxxxxxxx> patch [1] but it changes > the function serial_omap_update_rts() that raises and lows the Ready-to-Send > control signal. Also, it forces to update the RTS signal when the serial-core > calls serial_omap_set_mctrl(). > > [1]: http://www.spinics.net/lists/linux-omap/msg58546.html > > Signed-off-by: Javier Martinez Canillas <martinez.javier@xxxxxxxxx> > --- > arch/arm/plat-omap/include/plat/omap-serial.h | 2 + > drivers/tty/serial/Makefile | 2 +- > drivers/tty/serial/omap-serial.c | 139 ++++++++++++++++++++++-- > include/linux/serial_reg.h | 2 + > 4 files changed, 132 insertions(+), 13 deletions(-) > > diff --git a/arch/arm/plat-omap/include/plat/omap-serial.h b/arch/arm/plat-omap/include/plat/omap-serial.h > index 2682043..b7c2c29 100644 > --- a/arch/arm/plat-omap/include/plat/omap-serial.h > +++ b/arch/arm/plat-omap/include/plat/omap-serial.h > @@ -111,6 +111,8 @@ struct uart_omap_port { > unsigned char msr_saved_flags; > char name[20]; > unsigned long port_activity; > + struct serial_rs485 rs485; > + unsigned int tx_in_progress:1, tx_wait_end:1; > }; > > #endif /* __OMAP_SERIAL_H__ */ > diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile > index 83b4da6..865f238 100644 > --- a/drivers/tty/serial/Makefile > +++ b/drivers/tty/serial/Makefile > @@ -71,7 +71,7 @@ obj-$(CONFIG_SERIAL_VR41XX) += vr41xx_siu.o > obj-$(CONFIG_SERIAL_SGI_IOC4) += ioc4_serial.o > obj-$(CONFIG_SERIAL_SGI_IOC3) += ioc3_serial.o > obj-$(CONFIG_SERIAL_ATMEL) += atmel_serial.o > -obj-$(CONFIG_SERIAL_UARTLITE) += uartlite.o > +#obj-$(CONFIG_SERIAL_UARTLITE) += uartlite.o > obj-$(CONFIG_SERIAL_MSM) += msm_serial.o > obj-$(CONFIG_SERIAL_MSM_HS) += msm_serial_hs.o > obj-$(CONFIG_SERIAL_NETX) += netx-serial.o > diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c > index 5e713d3..d1789f4 100644 > --- a/drivers/tty/serial/omap-serial.c > +++ b/drivers/tty/serial/omap-serial.c > @@ -37,6 +37,7 @@ > #include <linux/clk.h> > #include <linux/serial_core.h> > #include <linux/irq.h> > +#include <linux/uaccess.h> > > #include <plat/dma.h> > #include <plat/dmtimer.h> > @@ -114,6 +115,56 @@ static void serial_omap_enable_ms(struct uart_port *port) > serial_out(up, UART_IER, up->ier); > } > > +static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up) > +{ > + if (!(up->ier & UART_IER_THRI)) { > + up->ier |= UART_IER_THRI; > + serial_out(up, UART_IER, up->ier); > + } > +} > + > +static inline void serial_omap_disable_ier_thri(struct uart_omap_port *up) > +{ > + if (up->ier & UART_IER_THRI) { > + up->ier &= ~UART_IER_THRI; > + serial_out(up, UART_IER, up->ier); > + } > +} > + > +static inline void serial_omap_thri_mode(struct uart_omap_port *up) > +{ > + unsigned char scr = serial_in(up, UART_OMAP_SCR); > + > + if (up->tx_wait_end) > + scr |= UART_OMAP_SCR_TX_EMPTY_CTL_IT; > + else > + scr &= ~UART_OMAP_SCR_TX_EMPTY_CTL_IT; > + serial_out(up, UART_OMAP_SCR, scr); > +} > + > + > +static inline void serial_omap_update_rts(struct uart_omap_port *up) > +{ > + unsigned char mcr = up->mcr; > + int rts_on_send = up->rs485.flags & SER_RS485_RTS_ON_SEND; > + > + if (up->rs485.flags & SER_RS485_ENABLED) { > + if (up->tx_in_progress) { > + if (rts_on_send) > + mcr |= UART_MCR_RTS; > + else > + mcr &= ~UART_MCR_RTS; > + } else { > + if (rts_on_send) > + mcr &= ~UART_MCR_RTS; > + else > + mcr |= ~UART_MCR_RTS; > + } > + } > + > + serial_out(up, UART_MCR, mcr); > +} > + > static void serial_omap_stop_tx(struct uart_port *port) > { > struct uart_omap_port *up = (struct uart_omap_port *)port; > @@ -131,9 +182,14 @@ static void serial_omap_stop_tx(struct uart_port *port) > up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE; > } > > - if (up->ier & UART_IER_THRI) { > - up->ier &= ~UART_IER_THRI; > - serial_out(up, UART_IER, up->ier); > + if (!(up->rs485.flags & SER_RS485_ENABLED)) > + serial_omap_disable_ier_thri(up); > + else { > + up->tx_in_progress = 0; > + serial_omap_update_rts(up); > + up->tx_wait_end = 1; > + serial_omap_thri_mode(up); > + serial_omap_enable_ier_thri(up); > } > } > > @@ -246,14 +302,6 @@ static void transmit_chars(struct uart_omap_port *up) > serial_omap_stop_tx(&up->port); > } > > -static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up) > -{ > - if (!(up->ier & UART_IER_THRI)) { > - up->ier |= UART_IER_THRI; > - serial_out(up, UART_IER, up->ier); > - } > -} > - > static void serial_omap_start_tx(struct uart_port *port) > { > struct uart_omap_port *up = (struct uart_omap_port *)port; > @@ -261,6 +309,18 @@ static void serial_omap_start_tx(struct uart_port *port) > unsigned int start; > int ret = 0; > > + if (up->rs485.flags & SER_RS485_ENABLED) { > + if (!up->tx_in_progress) { > + up->tx_in_progress = 1; > + serial_omap_update_rts(up); > + } > + if (up->tx_wait_end) { > + up->tx_wait_end = 0; > + serial_omap_thri_mode(up); > + serial_omap_disable_ier_thri(up); > + } > + } > + > if (!up->use_dma) { > serial_omap_enable_ier_thri(up); > return; > @@ -343,6 +403,11 @@ static unsigned int check_modem_status(struct uart_omap_port *up) > return status; > } > > +static inline unsigned int __serial_omap_tx_empty(struct uart_omap_port *up) > +{ > + return serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0; > +} > + > /** > * serial_omap_irq() - This handles the interrupt from one port > * @irq: uart port irq number > @@ -359,6 +424,16 @@ static inline irqreturn_t serial_omap_irq(int irq, void *dev_id) > return IRQ_NONE; > > spin_lock_irqsave(&up->port.lock, flags); > + if (up->tx_wait_end && (iir & UART_IIR_THRI) && > + __serial_omap_tx_empty(up)) { > + up->tx_wait_end = 0; > + up->tx_in_progress = 0; > + serial_omap_thri_mode(up); > + serial_omap_update_rts(up); > + serial_omap_disable_ier_thri(up); > + spin_unlock_irqrestore(&up->port.lock, flags); > + return IRQ_HANDLED; > + } > lsr = serial_in(up, UART_LSR); > if (iir & UART_IIR_RLSI) { > if (!up->use_dma) { > @@ -390,7 +465,7 @@ static unsigned int serial_omap_tx_empty(struct uart_port *port) > > dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->pdev->id); > spin_lock_irqsave(&up->port.lock, flags); > - ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0; > + ret = __serial_omap_tx_empty(up); > spin_unlock_irqrestore(&up->port.lock, flags); > > return ret; > @@ -434,6 +509,10 @@ static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl) > mcr |= UART_MCR_LOOP; > > mcr |= up->mcr; > + > + if (up->rs485.flags & SER_RS485_ENABLED) > + serial_omap_update_rts(up); > + > serial_out(up, UART_MCR, mcr); > } > > @@ -1028,6 +1107,41 @@ static inline void serial_omap_add_console_port(struct uart_omap_port *up) > > #endif > > +static int > +serial_omap_ioctl(struct uart_port *port, unsigned int cmd, unsigned long arg) > +{ > + struct serial_rs485 rs485conf; > + struct uart_omap_port *up = (struct uart_omap_port *)port; > + unsigned long flags; > + > + switch (cmd) { > + case TIOCSRS485: > + if (copy_from_user(&rs485conf, (struct serial_rs485 *) arg, > + sizeof(rs485conf))) > + return -EFAULT; > + > + spin_lock_irqsave(&up->port.lock, flags); > + if (!(rs485conf.flags & SER_RS485_ENABLED)) { > + up->tx_in_progress = 0; > + up->tx_wait_end = 0; > + } > + up->rs485 = rs485conf; > + serial_omap_update_rts(up); > + serial_omap_thri_mode(up); > + spin_unlock_irqrestore(&up->port.lock, flags); > + > + case TIOCGRS485: > + if (copy_to_user((struct serial_rs485 *) arg, > + &(up->rs485), sizeof(rs485conf))) > + return -EFAULT; > + break; > + > + default: > + return -ENOIOCTLCMD; > + } > + return 0; > +} > + > static struct uart_ops serial_omap_pops = { > .tx_empty = serial_omap_tx_empty, > .set_mctrl = serial_omap_set_mctrl, > @@ -1041,6 +1155,7 @@ static struct uart_ops serial_omap_pops = { > .shutdown = serial_omap_shutdown, > .set_termios = serial_omap_set_termios, > .pm = serial_omap_pm, > + .ioctl = serial_omap_ioctl, > .type = serial_omap_type, > .release_port = serial_omap_release_port, > .request_port = serial_omap_request_port, > diff --git a/include/linux/serial_reg.h b/include/linux/serial_reg.h > index c75bda3..dc6a3f7 100644 > --- a/include/linux/serial_reg.h > +++ b/include/linux/serial_reg.h > @@ -362,5 +362,7 @@ > #define UART_OMAP_MDR1_CIR_MODE 0x06 /* CIR mode */ > #define UART_OMAP_MDR1_DISABLE 0x07 /* Disable (default state) */ > > +#define UART_OMAP_SCR_TX_EMPTY_CTL_IT 0x04 /* TX Empty IRQ mode */ > + > #endif /* _LINUX_SERIAL_REG_H */ > > -- > 1.7.4.1 > > Hello, Any comments for this patch? Best regards, -- Javier Martínez Canillas (+34) 682 39 81 69 Barcelona, Spain -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
