diff options
| -rw-r--r-- | drivers/mmc/card/sdio_uart.c | 201 |
1 files changed, 119 insertions, 82 deletions
diff --git a/drivers/mmc/card/sdio_uart.c b/drivers/mmc/card/sdio_uart.c index 31f70233133..95027b03c64 100644 --- a/drivers/mmc/card/sdio_uart.c +++ b/drivers/mmc/card/sdio_uart.c @@ -77,7 +77,6 @@ struct sdio_uart_port { struct kref kref; struct tty_struct *tty; unsigned int index; - unsigned int opened; struct sdio_func *func; struct mutex func_lock; struct task_struct *in_sdio_uart_irq; @@ -150,6 +149,7 @@ 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); @@ -170,11 +170,10 @@ static void sdio_uart_port_remove(struct sdio_uart_port *port) sdio_claim_host(func); port->func = NULL; mutex_unlock(&port->func_lock); - if (port->opened) { - struct tty_struct *tty = tty_port_tty_get(&port->port); - /* tty_hangup is async so is this safe as is ?? */ - if (tty) - tty_hangup(tty); + 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); @@ -560,13 +559,46 @@ 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) +/** + * 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) { - unsigned long page; - int ret = -ENOMEM; - struct tty_struct *tty = tty_port_tty_get(&port->port); + struct sdio_uart_port *port = + container_of(tport, struct sdio_uart_port, port); + if (onoff == 0) + sdio_uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS); + else + sdio_uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS); +} - /* FIXME: What if it is NULL ?? */ +/** + * 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; /* * Set the TTY IO error marker - we will only clear this @@ -577,7 +609,7 @@ static int sdio_uart_startup(struct sdio_uart_port *port) /* Initialise and allocate the transmit buffer. */ page = __get_free_page(GFP_KERNEL); if (!page) - goto err0; + return -ENOMEM; port->xmit.buf = (unsigned char *)page; circ_clear(&port->xmit); @@ -631,7 +663,6 @@ static int sdio_uart_startup(struct sdio_uart_port *port) sdio_uart_irq(port->func); sdio_uart_release_func(port); - tty_kref_put(tty); return 0; err3: @@ -640,15 +671,25 @@ err2: sdio_uart_release_func(port); err1: free_page((unsigned long)port->xmit.buf); -err0: - tty_kref_put(tty); 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; - struct tty_struct *tty; ret = sdio_uart_claim_func(port); if (ret) @@ -656,14 +697,6 @@ static void sdio_uart_shutdown(struct sdio_uart_port *port) sdio_uart_stop_rx(port); - /* TODO: wait here for TX FIFO to drain */ - - tty = tty_port_tty_get(&port->port); - /* Turn off DTR and RTS early. */ - if (tty && (tty->termios->c_cflag & HUPCL)) - sdio_uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS); - tty_kref_put(tty); - /* Disable interrupts from this port */ sdio_release_irq(port->func); port->ier = 0; @@ -688,74 +721,68 @@ skip: free_page((unsigned long)port->xmit.buf); } -static int sdio_uart_open(struct tty_struct *tty, struct file *filp) -{ - struct sdio_uart_port *port; - int ret; - - port = sdio_uart_port_get(tty->index); - if (!port) - return -ENODEV; - - mutex_lock(&port->port.mutex); +/** + * 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) + */ - /* - * 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->port.mutex); +static int sdio_uart_install(struct tty_driver *driver, struct tty_struct *tty) +{ + 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 -EBUSY; - } + return ret; - if (!port->opened) { - tty->driver_data = port; - tty_port_tty_set(&port->port, tty); - ret = sdio_uart_startup(port); - if (ret) { - tty->driver_data = NULL; - tty_port_tty_set(&port->port, NULL); - mutex_unlock(&port->port.mutex); - sdio_uart_port_put(port); - return ret; - } - } - port->opened++; - mutex_unlock(&port->port.mutex); - return 0; } -static void sdio_uart_close(struct tty_struct *tty, struct file * filp) +/** + * 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 + */ + +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); +} - if (!port) - return; +/* + * Open/close/hangup is now entirely boilerplate + */ - mutex_lock(&port->port.mutex); - BUG_ON(!port->opened); +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); +} - /* - * 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->port.mutex); - return; - } +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->opened == 0) { - tty->closing = 1; - sdio_uart_shutdown(port); - tty_ldisc_flush(tty); - tty_port_tty_set(&port->port, NULL); - tty->driver_data = NULL; - tty->closing = 0; - } - mutex_unlock(&port->port.mutex); - 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, @@ -1021,6 +1048,12 @@ 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, + .shutdown = sdio_uart_shutdown, + .activate = sdio_uart_activate, +}; + static const struct tty_operations sdio_uart_ops = { .open = sdio_uart_open, .close = sdio_uart_close, @@ -1031,9 +1064,12 @@ 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, }; @@ -1096,6 +1132,7 @@ 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) { |