diff options
Diffstat (limited to 'drivers/mmc/card/sdio_uart.c')
-rw-r--r-- | drivers/mmc/card/sdio_uart.c | 339 |
1 files changed, 218 insertions, 121 deletions
diff --git a/drivers/mmc/card/sdio_uart.c b/drivers/mmc/card/sdio_uart.c index 36a8d53ad2a..f53755533e7 100644 --- a/drivers/mmc/card/sdio_uart.c +++ b/drivers/mmc/card/sdio_uart.c @@ -29,6 +29,7 @@ #include <linux/module.h> #include <linux/init.h> #include <linux/kernel.h> +#include <linux/sched.h> #include <linux/mutex.h> #include <linux/seq_file.h> #include <linux/serial_reg.h> @@ -73,11 +74,10 @@ struct uart_icount { }; struct sdio_uart_port { + struct tty_port port; struct kref kref; struct tty_struct *tty; unsigned int index; - unsigned int opened; - struct mutex open_lock; struct sdio_func *func; struct mutex func_lock; struct task_struct *in_sdio_uart_irq; @@ -87,6 +87,7 @@ struct sdio_uart_port { struct uart_icount icount; unsigned int uartclk; unsigned int mctrl; + unsigned int rx_mctrl; unsigned int read_status_mask; unsigned int ignore_status_mask; unsigned char x_char; @@ -102,7 +103,6 @@ static int sdio_uart_add_port(struct sdio_uart_port *port) int index, ret = -EBUSY; kref_init(&port->kref); - mutex_init(&port->open_lock); mutex_init(&port->func_lock); spin_lock_init(&port->write_lock); @@ -151,6 +151,7 @@ static void sdio_uart_port_put(struct sdio_uart_port *port) static void sdio_uart_port_remove(struct sdio_uart_port *port) { struct sdio_func *func; + struct tty_struct *tty; BUG_ON(sdio_uart_table[port->index] != port); @@ -165,15 +166,19 @@ static void sdio_uart_port_remove(struct sdio_uart_port *port) * give up on that port ASAP. * Beware: the lock ordering is critical. */ - mutex_lock(&port->open_lock); + mutex_lock(&port->port.mutex); mutex_lock(&port->func_lock); func = port->func; sdio_claim_host(func); port->func = NULL; mutex_unlock(&port->func_lock); - if (port->opened) - tty_hangup(port->tty); - mutex_unlock(&port->open_lock); + tty = tty_port_tty_get(&port->port); + /* tty_hangup is async so is this safe as is ?? */ + if (tty) { + tty_hangup(tty); + tty_kref_put(tty); + } + mutex_unlock(&port->port.mutex); sdio_release_irq(func); sdio_disable_func(func); sdio_release_host(func); @@ -217,6 +222,8 @@ static unsigned int sdio_uart_get_mctrl(struct sdio_uart_port *port) unsigned char status; unsigned int ret; + /* FIXME: What stops this losing the delta bits and breaking + sdio_uart_check_modem_status ? */ status = sdio_in(port, UART_MSR); ret = 0; @@ -231,7 +238,8 @@ static unsigned int sdio_uart_get_mctrl(struct sdio_uart_port *port) return ret; } -static void sdio_uart_write_mctrl(struct sdio_uart_port *port, unsigned int mctrl) +static void sdio_uart_write_mctrl(struct sdio_uart_port *port, + unsigned int mctrl) { unsigned char mcr = 0; @@ -387,9 +395,10 @@ static void sdio_uart_stop_rx(struct sdio_uart_port *port) sdio_out(port, UART_IER, port->ier); } -static void sdio_uart_receive_chars(struct sdio_uart_port *port, unsigned int *status) +static void sdio_uart_receive_chars(struct sdio_uart_port *port, + unsigned int *status) { - struct tty_struct *tty = port->tty; + struct tty_struct *tty = tty_port_tty_get(&port->port); unsigned int ch, flag; int max_count = 256; @@ -399,7 +408,7 @@ static void sdio_uart_receive_chars(struct sdio_uart_port *port, unsigned int *s port->icount.rx++; if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE | - UART_LSR_FE | UART_LSR_OE))) { + UART_LSR_FE | UART_LSR_OE))) { /* * For statistics only */ @@ -417,33 +426,39 @@ static void sdio_uart_receive_chars(struct sdio_uart_port *port, unsigned int *s * Mask off conditions which should be ignored. */ *status &= port->read_status_mask; - if (*status & UART_LSR_BI) { + if (*status & UART_LSR_BI) flag = TTY_BREAK; - } else if (*status & UART_LSR_PE) + else if (*status & UART_LSR_PE) flag = TTY_PARITY; else if (*status & UART_LSR_FE) flag = TTY_FRAME; } if ((*status & port->ignore_status_mask & ~UART_LSR_OE) == 0) - tty_insert_flip_char(tty, ch, flag); + if (tty) + tty_insert_flip_char(tty, ch, flag); /* * Overrun is special. Since it's reported immediately, * it doesn't affect the current character. */ if (*status & ~port->ignore_status_mask & UART_LSR_OE) - tty_insert_flip_char(tty, 0, TTY_OVERRUN); + if (tty) + tty_insert_flip_char(tty, 0, TTY_OVERRUN); *status = sdio_in(port, UART_LSR); } while ((*status & UART_LSR_DR) && (max_count-- > 0)); - tty_flip_buffer_push(tty); + if (tty) { + tty_flip_buffer_push(tty); + tty_kref_put(tty); + } } static void sdio_uart_transmit_chars(struct sdio_uart_port *port) { struct circ_buf *xmit = &port->xmit; int count; + struct tty_struct *tty; if (port->x_char) { sdio_out(port, UART_TX, port->x_char); @@ -451,8 +466,13 @@ static void sdio_uart_transmit_chars(struct sdio_uart_port *port) port->x_char = 0; return; } - if (circ_empty(xmit) || port->tty->stopped || port->tty->hw_stopped) { + + tty = tty_port_tty_get(&port->port); + + if (tty == NULL || circ_empty(xmit) || + tty->stopped || tty->hw_stopped) { sdio_uart_stop_tx(port); + tty_kref_put(tty); return; } @@ -466,15 +486,17 @@ static void sdio_uart_transmit_chars(struct sdio_uart_port *port) } while (--count > 0); if (circ_chars_pending(xmit) < WAKEUP_CHARS) - tty_wakeup(port->tty); + tty_wakeup(tty); if (circ_empty(xmit)) sdio_uart_stop_tx(port); + tty_kref_put(tty); } static void sdio_uart_check_modem_status(struct sdio_uart_port *port) { int status; + struct tty_struct *tty; status = sdio_in(port, UART_MSR); @@ -485,25 +507,39 @@ static void sdio_uart_check_modem_status(struct sdio_uart_port *port) port->icount.rng++; if (status & UART_MSR_DDSR) port->icount.dsr++; - if (status & UART_MSR_DDCD) + if (status & UART_MSR_DDCD) { port->icount.dcd++; + /* DCD raise - wake for open */ + if (status & UART_MSR_DCD) + wake_up_interruptible(&port->port.open_wait); + else { + /* DCD drop - hang up if tty attached */ + tty = tty_port_tty_get(&port->port); + if (tty) { + tty_hangup(tty); + tty_kref_put(tty); + } + } + } if (status & UART_MSR_DCTS) { port->icount.cts++; - if (port->tty->termios->c_cflag & CRTSCTS) { + tty = tty_port_tty_get(&port->port); + if (tty && (tty->termios->c_cflag & CRTSCTS)) { int cts = (status & UART_MSR_CTS); - if (port->tty->hw_stopped) { + if (tty->hw_stopped) { if (cts) { - port->tty->hw_stopped = 0; + tty->hw_stopped = 0; sdio_uart_start_tx(port); - tty_wakeup(port->tty); + tty_wakeup(tty); } } else { if (!cts) { - port->tty->hw_stopped = 1; + tty->hw_stopped = 1; sdio_uart_stop_tx(port); } } } + tty_kref_put(tty); } } @@ -540,8 +576,62 @@ static void sdio_uart_irq(struct sdio_func *func) port->in_sdio_uart_irq = NULL; } -static int sdio_uart_startup(struct sdio_uart_port *port) +static int uart_carrier_raised(struct tty_port *tport) +{ + struct sdio_uart_port *port = + container_of(tport, struct sdio_uart_port, port); + unsigned int ret = sdio_uart_claim_func(port); + if (ret) /* Missing hardware shoudn't block for carrier */ + return 1; + ret = sdio_uart_get_mctrl(port); + sdio_uart_release_func(port); + if (ret & TIOCM_CAR) + return 1; + return 0; +} + +/** + * uart_dtr_rts - port helper to set uart signals + * @tport: tty port to be updated + * @onoff: set to turn on DTR/RTS + * + * Called by the tty port helpers when the modem signals need to be + * adjusted during an open, close and hangup. + */ + +static void uart_dtr_rts(struct tty_port *tport, int onoff) { + struct sdio_uart_port *port = + container_of(tport, struct sdio_uart_port, port); + int ret = sdio_uart_claim_func(port); + if (ret) + return; + if (onoff == 0) + sdio_uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS); + else + sdio_uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS); + sdio_uart_release_func(port); +} + +/** + * sdio_uart_activate - start up hardware + * @tport: tty port to activate + * @tty: tty bound to this port + * + * Activate a tty port. The port locking guarantees us this will be + * run exactly once per set of opens, and if successful will see the + * shutdown method run exactly once to match. Start up and shutdown are + * protected from each other by the internal locking and will not run + * at the same time even during a hangup event. + * + * If we successfully start up the port we take an extra kref as we + * will keep it around until shutdown when the kref is dropped. + */ + +static int sdio_uart_activate(struct tty_port *tport, struct tty_struct *tty) +{ + struct sdio_uart_port *port = + container_of(tport, struct sdio_uart_port, port); unsigned long page; int ret; @@ -549,7 +639,7 @@ static int sdio_uart_startup(struct sdio_uart_port *port) * Set the TTY IO error marker - we will only clear this * once we have successfully opened the port. */ - set_bit(TTY_IO_ERROR, &port->tty->flags); + set_bit(TTY_IO_ERROR, &tty->flags); /* Initialise and allocate the transmit buffer. */ page = __get_free_page(GFP_KERNEL); @@ -574,7 +664,7 @@ static int sdio_uart_startup(struct sdio_uart_port *port) */ sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO); sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO | - UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); + UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); sdio_out(port, UART_FCR, 0); /* @@ -590,19 +680,19 @@ static int sdio_uart_startup(struct sdio_uart_port *port) */ sdio_out(port, UART_LCR, UART_LCR_WLEN8); - port->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE; + port->ier = UART_IER_RLSI|UART_IER_RDI|UART_IER_RTOIE|UART_IER_UUE; port->mctrl = TIOCM_OUT2; - sdio_uart_change_speed(port, port->tty->termios, NULL); + sdio_uart_change_speed(port, tty->termios, NULL); - if (port->tty->termios->c_cflag & CBAUD) + if (tty->termios->c_cflag & CBAUD) sdio_uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR); - if (port->tty->termios->c_cflag & CRTSCTS) + if (tty->termios->c_cflag & CRTSCTS) if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS)) - port->tty->hw_stopped = 1; + tty->hw_stopped = 1; - clear_bit(TTY_IO_ERROR, &port->tty->flags); + clear_bit(TTY_IO_ERROR, &tty->flags); /* Kick the IRQ handler once while we're still holding the host lock */ sdio_uart_irq(port->func); @@ -619,8 +709,20 @@ err1: return ret; } -static void sdio_uart_shutdown(struct sdio_uart_port *port) +/** + * sdio_uart_shutdown - stop hardware + * @tport: tty port to shut down + * + * Deactivate a tty port. The port locking guarantees us this will be + * run only if a successful matching activate already ran. The two are + * protected from each other by the internal locking and will not run + * at the same time even during a hangup event. + */ + +static void sdio_uart_shutdown(struct tty_port *tport) { + struct sdio_uart_port *port = + container_of(tport, struct sdio_uart_port, port); int ret; ret = sdio_uart_claim_func(port); @@ -629,13 +731,7 @@ static void sdio_uart_shutdown(struct sdio_uart_port *port) sdio_uart_stop_rx(port); - /* TODO: wait here for TX FIFO to drain */ - - /* Turn off DTR and RTS early. */ - if (port->tty->termios->c_cflag & HUPCL) - sdio_uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS); - - /* Disable interrupts from this port */ + /* Disable interrupts from this port */ sdio_release_irq(port->func); port->ier = 0; sdio_out(port, UART_IER, 0); @@ -659,77 +755,70 @@ skip: free_page((unsigned long)port->xmit.buf); } -static int sdio_uart_open (struct tty_struct *tty, struct file * filp) +/** + * sdio_uart_install - install method + * @driver: the driver in use (sdio_uart in our case) + * @tty: the tty being bound + * + * Look up and bind the tty and the driver together. Initialize + * any needed private data (in our case the termios) + */ + +static int sdio_uart_install(struct tty_driver *driver, struct tty_struct *tty) { - struct sdio_uart_port *port; - int ret; + int idx = tty->index; + struct sdio_uart_port *port = sdio_uart_port_get(idx); + int ret = tty_init_termios(tty); + + if (ret == 0) { + tty_driver_kref_get(driver); + tty->count++; + /* This is the ref sdio_uart_port get provided */ + tty->driver_data = port; + driver->ttys[idx] = tty; + } else + sdio_uart_port_put(port); + return ret; +} - port = sdio_uart_port_get(tty->index); - if (!port) - return -ENODEV; +/** + * sdio_uart_cleanup - called on the last tty kref drop + * @tty: the tty being destroyed + * + * Called asynchronously when the last reference to the tty is dropped. + * We cannot destroy the tty->driver_data port kref until this point + */ - mutex_lock(&port->open_lock); +static void sdio_uart_cleanup(struct tty_struct *tty) +{ + struct sdio_uart_port *port = tty->driver_data; + tty->driver_data = NULL; /* Bug trap */ + sdio_uart_port_put(port); +} - /* - * Make sure not to mess up with a dead port - * which has not been closed yet. - */ - if (tty->driver_data && tty->driver_data != port) { - mutex_unlock(&port->open_lock); - sdio_uart_port_put(port); - return -EBUSY; - } +/* + * Open/close/hangup is now entirely boilerplate + */ - if (!port->opened) { - tty->driver_data = port; - port->tty = tty; - ret = sdio_uart_startup(port); - if (ret) { - tty->driver_data = NULL; - port->tty = NULL; - mutex_unlock(&port->open_lock); - sdio_uart_port_put(port); - return ret; - } - } - port->opened++; - mutex_unlock(&port->open_lock); - return 0; +static int sdio_uart_open(struct tty_struct *tty, struct file *filp) +{ + struct sdio_uart_port *port = tty->driver_data; + return tty_port_open(&port->port, tty, filp); } static void sdio_uart_close(struct tty_struct *tty, struct file * filp) { struct sdio_uart_port *port = tty->driver_data; + tty_port_close(&port->port, tty, filp); +} - if (!port) - return; - - mutex_lock(&port->open_lock); - BUG_ON(!port->opened); - - /* - * This is messy. The tty layer calls us even when open() - * returned an error. Ignore this close request if tty->count - * is larger than port->count. - */ - if (tty->count > port->opened) { - mutex_unlock(&port->open_lock); - return; - } - - if (--port->opened == 0) { - tty->closing = 1; - sdio_uart_shutdown(port); - tty_ldisc_flush(tty); - port->tty = NULL; - tty->driver_data = NULL; - tty->closing = 0; - } - mutex_unlock(&port->open_lock); - sdio_uart_port_put(port); +static void sdio_uart_hangup(struct tty_struct *tty) +{ + struct sdio_uart_port *port = tty->driver_data; + tty_port_hangup(&port->port); } -static int sdio_uart_write(struct tty_struct * tty, const unsigned char *buf, +static int sdio_uart_write(struct tty_struct *tty, const unsigned char *buf, int count) { struct sdio_uart_port *port = tty->driver_data; @@ -754,7 +843,7 @@ static int sdio_uart_write(struct tty_struct * tty, const unsigned char *buf, } spin_unlock(&port->write_lock); - if ( !(port->ier & UART_IER_THRI)) { + if (!(port->ier & UART_IER_THRI)) { int err = sdio_uart_claim_func(port); if (!err) { sdio_uart_start_tx(port); @@ -841,17 +930,12 @@ static void sdio_uart_unthrottle(struct tty_struct *tty) sdio_uart_release_func(port); } -static void sdio_uart_set_termios(struct tty_struct *tty, struct ktermios *old_termios) +static void sdio_uart_set_termios(struct tty_struct *tty, + struct ktermios *old_termios) { struct sdio_uart_port *port = tty->driver_data; unsigned int cflag = tty->termios->c_cflag; -#define RELEVANT_IFLAG(iflag) ((iflag) & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK)) - - if ((cflag ^ old_termios->c_cflag) == 0 && - RELEVANT_IFLAG(tty->termios->c_iflag ^ old_termios->c_iflag) == 0) - return; - if (sdio_uart_claim_func(port) != 0) return; @@ -925,8 +1009,8 @@ static int sdio_uart_tiocmset(struct tty_struct *tty, struct file *file, struct sdio_uart_port *port = tty->driver_data; int result; - result =sdio_uart_claim_func(port); - if(!result) { + result = sdio_uart_claim_func(port); + if (!result) { sdio_uart_update_mctrl(port, set, clear); sdio_uart_release_func(port); } @@ -944,33 +1028,33 @@ static int sdio_uart_proc_show(struct seq_file *m, void *v) struct sdio_uart_port *port = sdio_uart_port_get(i); if (port) { seq_printf(m, "%d: uart:SDIO", i); - if(capable(CAP_SYS_ADMIN)) { + if (capable(CAP_SYS_ADMIN)) { seq_printf(m, " tx:%d rx:%d", - port->icount.tx, port->icount.rx); + port->icount.tx, port->icount.rx); if (port->icount.frame) seq_printf(m, " fe:%d", - port->icount.frame); + port->icount.frame); if (port->icount.parity) seq_printf(m, " pe:%d", - port->icount.parity); + port->icount.parity); if (port->icount.brk) seq_printf(m, " brk:%d", - port->icount.brk); + port->icount.brk); if (port->icount.overrun) seq_printf(m, " oe:%d", - port->icount.overrun); + port->icount.overrun); if (port->icount.cts) seq_printf(m, " cts:%d", - port->icount.cts); + port->icount.cts); if (port->icount.dsr) seq_printf(m, " dsr:%d", - port->icount.dsr); + port->icount.dsr); if (port->icount.rng) seq_printf(m, " rng:%d", - port->icount.rng); + port->icount.rng); if (port->icount.dcd) seq_printf(m, " dcd:%d", - port->icount.dcd); + port->icount.dcd); } sdio_uart_port_put(port); seq_putc(m, '\n'); @@ -992,6 +1076,13 @@ static const struct file_operations sdio_uart_proc_fops = { .release = single_release, }; +static const struct tty_port_operations sdio_uart_port_ops = { + .dtr_rts = uart_dtr_rts, + .carrier_raised = uart_carrier_raised, + .shutdown = sdio_uart_shutdown, + .activate = sdio_uart_activate, +}; + static const struct tty_operations sdio_uart_ops = { .open = sdio_uart_open, .close = sdio_uart_close, @@ -1002,9 +1093,12 @@ static const struct tty_operations sdio_uart_ops = { .throttle = sdio_uart_throttle, .unthrottle = sdio_uart_unthrottle, .set_termios = sdio_uart_set_termios, + .hangup = sdio_uart_hangup, .break_ctl = sdio_uart_break_ctl, .tiocmget = sdio_uart_tiocmget, .tiocmset = sdio_uart_tiocmset, + .install = sdio_uart_install, + .cleanup = sdio_uart_cleanup, .proc_fops = &sdio_uart_proc_fops, }; @@ -1041,7 +1135,7 @@ static int sdio_uart_probe(struct sdio_func *func, } if (!tpl) { printk(KERN_WARNING - "%s: can't find tuple 0x91 subtuple 0 (SUBTPL_SIOREG) for GPS class\n", + "%s: can't find tuple 0x91 subtuple 0 (SUBTPL_SIOREG) for GPS class\n", sdio_func_id(func)); kfree(port); return -EINVAL; @@ -1066,13 +1160,16 @@ static int sdio_uart_probe(struct sdio_func *func, port->func = func; sdio_set_drvdata(func, port); + tty_port_init(&port->port); + port->port.ops = &sdio_uart_port_ops; ret = sdio_uart_add_port(port); if (ret) { kfree(port); } else { struct device *dev; - dev = tty_register_device(sdio_uart_tty_driver, port->index, &func->dev); + dev = tty_register_device(sdio_uart_tty_driver, + port->index, &func->dev); if (IS_ERR(dev)) { sdio_uart_port_remove(port); ret = PTR_ERR(dev); |