/* * linux/drivers/mmc/card/sdio_uart.c - SDIO UART/GPS driver * * Based on drivers/serial/8250.c and drivers/serial/serial_core.c * by Russell King. * * Author: Nicolas Pitre * Created: June 15, 2007 * Copyright: MontaVista Software, Inc. * * 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 * the Free Software Foundation; either version 2 of the License, or (at * your option) any later version. */ /* * Note: Although this driver assumes a 16550A-like UART implementation, * it is not possible to leverage the common 8250/16550 driver, nor the * core UART infrastructure, as they assumes direct access to the hardware * registers, often under a spinlock. This is not possible in the SDIO * context as SDIO access functions must be able to sleep. * * Because we need to lock the SDIO host to ensure an exclusive access to * the card, we simply rely on that lock to also prevent and serialize * concurrent access to the same port. */ #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> #include <linux/circ_buf.h> #include <linux/tty.h> #include <linux/tty_flip.h> #include <linux/kfifo.h> #include <linux/slab.h> #include <linux/mmc/core.h> #include <linux/mmc/card.h> #include <linux/mmc/sdio_func.h> #include <linux/mmc/sdio_ids.h> #define UART_NR 8 /* Number of UARTs this driver can handle */ #define FIFO_SIZE PAGE_SIZE #define WAKEUP_CHARS 256 struct uart_icount { __u32 cts; __u32 dsr; __u32 rng; __u32 dcd; __u32 rx; __u32 tx; __u32 frame; __u32 overrun; __u32 parity; __u32 brk; }; struct sdio_uart_port { struct tty_port port; struct kref kref; struct tty_struct *tty; unsigned int index; struct sdio_func *func; struct mutex func_lock; struct task_struct *in_sdio_uart_irq; unsigned int regs_offset; struct kfifo xmit_fifo; spinlock_t write_lock; 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; unsigned char ier; unsigned char lcr; }; static struct sdio_uart_port *sdio_uart_table[UART_NR]; static DEFINE_SPINLOCK(sdio_uart_table_lock); static int sdio_uart_add_port(struct sdio_uart_port *port) { int index, ret = -EBUSY; kref_init(&port->kref); mutex_init(&port->func_lock); spin_lock_init(&port->write_lock); if (kfifo_alloc(&port->xmit_fifo, FIFO_SIZE, GFP_KERNEL)) return -ENOMEM; spin_lock(&sdio_uart_table_lock); for (index = 0; index < UART_NR; index++) { if (!sdio_uart_table[index]) { port->index = index; sdio_uart_table[index] = port; ret = 0; break; } } spin_unlock(&sdio_uart_table_lock); return ret; } static struct sdio_uart_port *sdio_uart_port_get(unsigned index) { struct sdio_uart_port *port; if (index >= UART_NR) return NULL; spin_lock(&sdio_uart_table_lock); port = sdio_uart_table[index]; if (port) kref_get(&port->kref); spin_unlock(&sdio_uart_table_lock); return port; } static void sdio_uart_port_destroy(struct kref *kref) { struct sdio_uart_port *port = container_of(kref, struct sdio_uart_port, kref); kfifo_free(&port->xmit_fifo); kfree(port); } static void sdio_uart_port_put(struct sdio_uart_port *port) { kref_put(&port->kref, sdio_uart_port_destroy); } 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); spin_lock(&sdio_uart_table_lock); sdio_uart_table[port->index] = NULL; spin_unlock(&sdio_uart_table_lock); /* * We're killing a port that potentially still is in use by * the tty layer. Be careful to prevent any further access * to the SDIO function and arrange for the tty layer to * give up on that port ASAP. * Beware: the lock ordering is critical. */ 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); 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); sdio_uart_port_put(port); } static int sdio_uart_claim_func(struct sdio_uart_port *port) { mutex_lock(&port->func_lock); if (unlikely(!port->func)) { mutex_unlock(&port->func_lock); return -ENODEV; } if (likely(port->in_sdio_uart_irq != current)) sdio_claim_host(port->func); mutex_unlock(&port->func_lock); return 0; } static inline void sdio_uart_release_func(struct sdio_uart_port *port) { if (likely(port->in_sdio_uart_irq != current)) sdio_release_host(port->func); } static inline unsigned int sdio_in(struct sdio_uart_port *port, int offset) { unsigned char c; c = sdio_readb(port->func, port->regs_offset + offset, NULL); return c; } static inline void sdio_out(struct sdio_uart_port *port, int offset, int value) { sdio_writeb(port->func, value, port->regs_offset + offset, NULL); } 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; if (status & UART_MSR_DCD) ret |= TIOCM_CAR; if (status & UART_MSR_RI) ret |= TIOCM_RNG; if (status & UART_MSR_DSR) ret |= TIOCM_DSR; if (status & UART_MSR_CTS) ret |= TIOCM_CTS; return ret; } static void sdio_uart_write_mctrl(struct sdio_uart_port *port, unsigned int mctrl) { unsigned char mcr = 0; if (mctrl & TIOCM_RTS) mcr |= UART_MCR_RTS; if (mctrl & TIOCM_DTR) mcr |= UART_MCR_DTR; if (mctrl & TIOCM_OUT1) mcr |= UART_MCR_OUT1; if (mctrl & TIOCM_OUT2) mcr |= UART_MCR_OUT2; if (mctrl & TIOCM_LOOP) mcr |= UART_MCR_LOOP; sdio_out(port, UART_MCR, mcr); } static inline void sdio_uart_update_mctrl(struct sdio_uart_port *port, unsigned int set, unsigned int clear) { unsigned int old; old = port->mctrl; port->mctrl = (old & ~clear) | set; if (old != port->mctrl) sdio_uart_write_mctrl(port, port->mctrl); } #define sdio_uart_set_mctrl(port, x) sdio_uart_update_mctrl(port, x, 0) #define sdio_uart_clear_mctrl(port, x) sdio_uart_update_mctrl(port, 0, x) static void sdio_uart_change_speed(struct sdio_uart_port *port, struct ktermios *termios, struct ktermios *old) { unsigned char cval, fcr = 0; unsigned int baud, quot; switch (termios->c_cflag & CSIZE) { case CS5: cval = UART_LCR_WLEN5; break; case CS6: cval = UART_LCR_WLEN6; break; case CS7: cval = UART_LCR_WLEN7; break; default: case CS8: cval = UART_LCR_WLEN8; break; } if (termios->c_cflag & CSTOPB) cval |= UART_LCR_STOP; if (termios->c_cflag & PARENB) cval |= UART_LCR_PARITY; if (!(termios->c_cflag & PARODD)) cval |= UART_LCR_EPAR; for (;;) { baud = tty_termios_baud_rate(termios); if (baud == 0) baud = 9600; /* Special case: B0 rate. */ if (baud <= port->uartclk) break; /* * Oops, the quotient was zero. Try again with the old * baud rate if possible, otherwise default to 9600. */ termios->c_cflag &= ~CBAUD; if (old) { termios->c_cflag |= old->c_cflag & CBAUD; old = NULL; } else termios->c_cflag |= B9600; } quot = (2 * port->uartclk + baud) / (2 * baud); if (baud < 2400) fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1; else fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10; port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR; if (termios->c_iflag & INPCK) port->read_status_mask |= UART_LSR_FE | UART_LSR_PE; if (termios->c_iflag & (BRKINT | PARMRK)) port->read_status_mask |= UART_LSR_BI; /* * Characters to ignore */ port->ignore_status_mask = 0; if (termios->c_iflag & IGNPAR) port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE; if (termios->c_iflag & IGNBRK) { port->ignore_status_mask |= UART_LSR_BI; /* * If we're ignoring parity and break indicators, * ignore overruns too (for real raw support). */ if (termios->c_iflag & IGNPAR) port->ignore_status_mask |= UART_LSR_OE; } /* * ignore all characters if CREAD is not set */ if ((termios->c_cflag & CREAD) == 0) port->ignore_status_mask |= UART_LSR_DR; /* * CTS flow control flag and modem status interrupts */ port->ier &= ~UART_IER_MSI; if ((termios->c_cflag & CRTSCTS) || !(termios->c_cflag & CLOCAL)) port->ier |= UART_IER_MSI; port->lcr = cval; sdio_out(port, UART_IER, port->ier); sdio_out(port, UART_LCR, cval | UART_LCR_DLAB); sdio_out(port, UART_DLL, quot & 0xff); sdio_out(port, UART_DLM, quot >> 8); sdio_out(port, UART_LCR, cval); sdio_out(port, UART_FCR, fcr); sdio_uart_write_mctrl(port, port->mctrl); } static void sdio_uart_start_tx(struct sdio_uart_port *port) { if (!(port->ier & UART_IER_THRI)) { port->ier |= UART_IER_THRI; sdio_out(port, UART_IER, port->ier); } } static void sdio_uart_stop_tx(struct sdio_uart_port *port) { if (port->ier & UART_IER_THRI) { port->ier &= ~UART_IER_THRI; sdio_out(port, UART_IER, port->ier); } } static void sdio_uart_stop_rx(struct sdio_uart_port *port) { port->ier &= ~UART_IER_RLSI; port->read_status_mask &= ~UART_LSR_DR; sdio_out(port, UART_IER, port->ier); } static void sdio_uart_receive_chars(struct sdio_uart_port *port, unsigned int *status) { struct tty_struct *tty = tty_port_tty_get(&port->port); unsigned int ch, flag; int max_count = 256; do { ch = sdio_in(port, UART_RX); flag = TTY_NORMAL; port->icount.rx++; if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE | UART_LSR_FE | UART_LSR_OE))) { /* * For statistics only */ if (*status & UART_LSR_BI) { *status &= ~(UART_LSR_FE | UART_LSR_PE); port->icount.brk++; } else if (*status & UART_LSR_PE) port->icount.parity++; else if (*status & UART_LSR_FE) port->icount.frame++; if (*status & UART_LSR_OE) port->icount.overrun++; /* * Mask off conditions which should be ignored. */ *status &= port->read_status_mask; if (*status & UART_LSR_BI) flag = TTY_BREAK; 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) 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) if (tty) tty_insert_flip_char(tty, 0, TTY_OVERRUN); *status = sdio_in(port, UART_LSR); } while ((*status & UART_LSR_DR) && (max_count-- > 0)); if (tty) { tty_flip_buffer_push(tty); tty_kref_put(tty); } } static void sdio_uart_transmit_chars(struct sdio_uart_port *port) { struct kfifo *xmit = &port->xmit_fifo; int count; struct tty_struct *tty; u8 iobuf[16]; int len; if (port->x_char) { sdio_out(port, UART_TX, port->x_char); port->icount.tx++; port->x_char = 0; return; } tty = tty_port_tty_get(&port->port); if (tty == NULL || !kfifo_len(xmit) || tty->stopped || tty->hw_stopped) { sdio_uart_stop_tx(port); tty_kref_put(tty); return; } len = kfifo_out_locked(xmit, iobuf, 16, &port->write_lock); for (count = 0; count < len; count++) { sdio_out(port, UART_TX, iobuf[count]); port->icount.tx++; } len = kfifo_len(xmit); if (len < WAKEUP_CHARS) { tty_wakeup(tty); if (len == 0) 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); if ((status & UART_MSR_ANY_DELTA) == 0) return; if (status & UART_MSR_TERI) port->icount.rng++; if (status & UART_MSR_DDSR) port->icount.dsr++; 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++; tty = tty_port_tty_get(&port->port); if (tty && (tty->termios->c_cflag & CRTSCTS)) { int cts = (status & UART_MSR_CTS); if (tty->hw_stopped) { if (cts) { tty->hw_stopped = 0; sdio_uart_start_tx(port); tty_wakeup(tty); } } else { if (!cts) { tty->hw_stopped = 1; sdio_uart_stop_tx(port); } } } tty_kref_put(tty); } } /* * This handles the interrupt from one port. */ static void sdio_uart_irq(struct sdio_func *func) { struct sdio_uart_port *port = sdio_get_drvdata(func); unsigned int iir, lsr; /* * In a few places sdio_uart_irq() is called directly instead of * waiting for the actual interrupt to be raised and the SDIO IRQ * thread scheduled in order to reduce latency. However, some * interaction with the tty core may end up calling us back * (serial echo, flow control, etc.) through those same places * causing undesirable effects. Let's stop the recursion here. */ if (unlikely(port->in_sdio_uart_irq == current)) return; iir = sdio_in(port, UART_IIR); if (iir & UART_IIR_NO_INT) return; port->in_sdio_uart_irq = current; lsr = sdio_in(port, UART_LSR); if (lsr & UART_LSR_DR) sdio_uart_receive_chars(port, &lsr); sdio_uart_check_modem_status(port); if (lsr & UART_LSR_THRE) sdio_uart_transmit_chars(port); port->in_sdio_uart_irq = NULL; } 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 shouldn'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); int ret; /* * Set the TTY IO error marker - we will only clear this * once we have successfully opened the port. */ set_bit(TTY_IO_ERROR, &tty->flags); kfifo_reset(&port->xmit_fifo); ret = sdio_uart_claim_func(port); if (ret) return ret; ret = sdio_enable_func(port->func); if (ret) goto err1; ret = sdio_claim_irq(port->func, sdio_uart_irq); if (ret) goto err2; /* * Clear the FIFO buffers and disable them. * (they will be reenabled in sdio_change_speed()) */ 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); sdio_out(port, UART_FCR, 0); /* * Clear the interrupt registers. */ (void) sdio_in(port, UART_LSR); (void) sdio_in(port, UART_RX); (void) sdio_in(port, UART_IIR); (void) sdio_in(port, UART_MSR); /* * Now, initialize the UART */ sdio_out(port, UART_LCR, UART_LCR_WLEN8); port->ier = UART_IER_RLSI|UART_IER_RDI|UART_IER_RTOIE|UART_IER_UUE; port->mctrl = TIOCM_OUT2; sdio_uart_change_speed(port, tty->termios, NULL); if (tty->termios->c_cflag & CBAUD) sdio_uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR); if (tty->termios->c_cflag & CRTSCTS) if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS)) tty->hw_stopped = 1; 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); sdio_uart_release_func(port); return 0; err2: sdio_disable_func(port->func); err1: sdio_uart_release_func(port); return ret; } /** * 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); if (ret) return; sdio_uart_stop_rx(port); /* Disable interrupts from this port */ sdio_release_irq(port->func); port->ier = 0; sdio_out(port, UART_IER, 0); sdio_uart_clear_mctrl(port, TIOCM_OUT2); /* Disable break condition and FIFOs. */ port->lcr &= ~UART_LCR_SBC; sdio_out(port, UART_LCR, port->lcr); sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); sdio_out(port, UART_FCR, 0); sdio_disable_func(port->func); sdio_uart_release_func(port); } /** * 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) { 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; } /** * 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); } /* * Open/close/hangup is now entirely boilerplate */ 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); } 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, int count) { struct sdio_uart_port *port = tty->driver_data; int ret; if (!port->func) return -ENODEV; ret = kfifo_in_locked(&port->xmit_fifo, buf, count, &port->write_lock); if (!(port->ier & UART_IER_THRI)) { int err = sdio_uart_claim_func(port); if (!err) { sdio_uart_start_tx(port); sdio_uart_irq(port->func); sdio_uart_release_func(port); } else ret = err; } return ret; } static int sdio_uart_write_room(struct tty_struct *tty) { struct sdio_uart_port *port = tty->driver_data; return FIFO_SIZE - kfifo_len(&port->xmit_fifo); } static int sdio_uart_chars_in_buffer(struct tty_struct *tty) { struct sdio_uart_port *port = tty->driver_data; return kfifo_len(&port->xmit_fifo); } static void sdio_uart_send_xchar(struct tty_struct *tty, char ch) { struct sdio_uart_port *port = tty->driver_data; port->x_char = ch; if (ch && !(port->ier & UART_IER_THRI)) { if (sdio_uart_claim_func(port) != 0) return; sdio_uart_start_tx(port); sdio_uart_irq(port->func); sdio_uart_release_func(port); } } static void sdio_uart_throttle(struct tty_struct *tty) { struct sdio_uart_port *port = tty->driver_data; if (!I_IXOFF(tty) && !(tty->termios->c_cflag & CRTSCTS)) return; if (sdio_uart_claim_func(port) != 0) return; if (I_IXOFF(tty)) { port->x_char = STOP_CHAR(tty); sdio_uart_start_tx(port); } if (tty->termios->c_cflag & CRTSCTS) sdio_uart_clear_mctrl(port, TIOCM_RTS); sdio_uart_irq(port->func); sdio_uart_release_func(port); } static void sdio_uart_unthrottle(struct tty_struct *tty) { struct sdio_uart_port *port = tty->driver_data; if (!I_IXOFF(tty) && !(tty->termios->c_cflag & CRTSCTS)) return; if (sdio_uart_claim_func(port) != 0) return; if (I_IXOFF(tty)) { if (port->x_char) { port->x_char = 0; } else { port->x_char = START_CHAR(tty); sdio_uart_start_tx(port); } } if (tty->termios->c_cflag & CRTSCTS) sdio_uart_set_mctrl(port, TIOCM_RTS); sdio_uart_irq(port->func); sdio_uart_release_func(port); } 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; if (sdio_uart_claim_func(port) != 0) return; sdio_uart_change_speed(port, tty->termios, old_termios); /* Handle transition to B0 status */ if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD)) sdio_uart_clear_mctrl(port, TIOCM_RTS | TIOCM_DTR); /* Handle transition away from B0 status */ if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) { unsigned int mask = TIOCM_DTR; if (!(cflag & CRTSCTS) || !test_bit(TTY_THROTTLED, &tty->flags)) mask |= TIOCM_RTS; sdio_uart_set_mctrl(port, mask); } /* Handle turning off CRTSCTS */ if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) { tty->hw_stopped = 0; sdio_uart_start_tx(port); } /* Handle turning on CRTSCTS */ if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) { if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS)) { tty->hw_stopped = 1; sdio_uart_stop_tx(port); } } sdio_uart_release_func(port); } static int sdio_uart_break_ctl(struct tty_struct *tty, int break_state) { struct sdio_uart_port *port = tty->driver_data; int result; result = sdio_uart_claim_func(port); if (result != 0) return result; if (break_state == -1) port->lcr |= UART_LCR_SBC; else port->lcr &= ~UART_LCR_SBC; sdio_out(port, UART_LCR, port->lcr); sdio_uart_release_func(port); return 0; } static int sdio_uart_tiocmget(struct tty_struct *tty) { struct sdio_uart_port *port = tty->driver_data; int result; result = sdio_uart_claim_func(port); if (!result) { result = port->mctrl | sdio_uart_get_mctrl(port); sdio_uart_release_func(port); } return result; } static int sdio_uart_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear) { struct sdio_uart_port *port = tty->driver_data; int result; result = sdio_uart_claim_func(port); if (!result) { sdio_uart_update_mctrl(port, set, clear); sdio_uart_release_func(port); } return result; } static int sdio_uart_proc_show(struct seq_file *m, void *v) { int i; seq_printf(m, "serinfo:1.0 driver%s%s revision:%s\n", "", "", ""); for (i = 0; i < UART_NR; i++) { struct sdio_uart_port *port = sdio_uart_port_get(i); if (port) { seq_printf(m, "%d: uart:SDIO", i); if (capable(CAP_SYS_ADMIN)) { seq_printf(m, " tx:%d rx:%d", port->icount.tx, port->icount.rx); if (port->icount.frame) seq_printf(m, " fe:%d", port->icount.frame); if (port->icount.parity) seq_printf(m, " pe:%d", port->icount.parity); if (port->icount.brk) seq_printf(m, " brk:%d", port->icount.brk); if (port->icount.overrun) seq_printf(m, " oe:%d", port->icount.overrun); if (port->icount.cts) seq_printf(m, " cts:%d", port->icount.cts); if (port->icount.dsr) seq_printf(m, " dsr:%d", port->icount.dsr); if (port->icount.rng) seq_printf(m, " rng:%d", port->icount.rng); if (port->icount.dcd) seq_printf(m, " dcd:%d", port->icount.dcd); } sdio_uart_port_put(port); seq_putc(m, '\n'); } } return 0; } static int sdio_uart_proc_open(struct inode *inode, struct file *file) { return single_open(file, sdio_uart_proc_show, NULL); } static const struct file_operations sdio_uart_proc_fops = { .owner = THIS_MODULE, .open = sdio_uart_proc_open, .read = seq_read, .llseek = seq_lseek, .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, .write = sdio_uart_write, .write_room = sdio_uart_write_room, .chars_in_buffer = sdio_uart_chars_in_buffer, .send_xchar = sdio_uart_send_xchar, .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, }; static struct tty_driver *sdio_uart_tty_driver; static int sdio_uart_probe(struct sdio_func *func, const struct sdio_device_id *id) { struct sdio_uart_port *port; int ret; port = kzalloc(sizeof(struct sdio_uart_port), GFP_KERNEL); if (!port) return -ENOMEM; if (func->class == SDIO_CLASS_UART) { pr_warning("%s: need info on UART class basic setup\n", sdio_func_id(func)); kfree(port); return -ENOSYS; } else if (func->class == SDIO_CLASS_GPS) { /* * We need tuple 0x91. It contains SUBTPL_SIOREG * and SUBTPL_RCVCAPS. */ struct sdio_func_tuple *tpl; for (tpl = func->tuples; tpl; tpl = tpl->next) { if (tpl->code != 0x91) continue; if (tpl->size < 10) continue; if (tpl->data[1] == 0) /* SUBTPL_SIOREG */ break; } if (!tpl) { pr_warning( "%s: can't find tuple 0x91 subtuple 0 (SUBTPL_SIOREG) for GPS class\n", sdio_func_id(func)); kfree(port); return -EINVAL; } pr_debug("%s: Register ID = 0x%02x, Exp ID = 0x%02x\n", sdio_func_id(func), tpl->data[2], tpl->data[3]); port->regs_offset = (tpl->data[4] << 0) | (tpl->data[5] << 8) | (tpl->data[6] << 16); pr_debug("%s: regs offset = 0x%x\n", sdio_func_id(func), port->regs_offset); port->uartclk = tpl->data[7] * 115200; if (port->uartclk == 0) port->uartclk = 115200; pr_debug("%s: clk %d baudcode %u 4800-div %u\n", sdio_func_id(func), port->uartclk, tpl->data[7], tpl->data[8] | (tpl->data[9] << 8)); } else { kfree(port); return -EINVAL; } 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); if (IS_ERR(dev)) { sdio_uart_port_remove(port); ret = PTR_ERR(dev); } } return ret; } static void sdio_uart_remove(struct sdio_func *func) { struct sdio_uart_port *port = sdio_get_drvdata(func); tty_unregister_device(sdio_uart_tty_driver, port->index); sdio_uart_port_remove(port); } static const struct sdio_device_id sdio_uart_ids[] = { { SDIO_DEVICE_CLASS(SDIO_CLASS_UART) }, { SDIO_DEVICE_CLASS(SDIO_CLASS_GPS) }, { /* end: all zeroes */ }, }; MODULE_DEVICE_TABLE(sdio, sdio_uart_ids); static struct sdio_driver sdio_uart_driver = { .probe = sdio_uart_probe, .remove = sdio_uart_remove, .name = "sdio_uart", .id_table = sdio_uart_ids, }; static int __init sdio_uart_init(void) { int ret; struct tty_driver *tty_drv; sdio_uart_tty_driver = tty_drv = alloc_tty_driver(UART_NR); if (!tty_drv) return -ENOMEM; tty_drv->owner = THIS_MODULE; tty_drv->driver_name = "sdio_uart"; tty_drv->name = "ttySDIO"; tty_drv->major = 0; /* dynamically allocated */ tty_drv->minor_start = 0; tty_drv->type = TTY_DRIVER_TYPE_SERIAL; tty_drv->subtype = SERIAL_TYPE_NORMAL; tty_drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV; tty_drv->init_termios = tty_std_termios; tty_drv->init_termios.c_cflag = B4800 | CS8 | CREAD | HUPCL | CLOCAL; tty_drv->init_termios.c_ispeed = 4800; tty_drv->init_termios.c_ospeed = 4800; tty_set_operations(tty_drv, &sdio_uart_ops); ret = tty_register_driver(tty_drv); if (ret) goto err1; ret = sdio_register_driver(&sdio_uart_driver); if (ret) goto err2; return 0; err2: tty_unregister_driver(tty_drv); err1: put_tty_driver(tty_drv); return ret; } static void __exit sdio_uart_exit(void) { sdio_unregister_driver(&sdio_uart_driver); tty_unregister_driver(sdio_uart_tty_driver); put_tty_driver(sdio_uart_tty_driver); } module_init(sdio_uart_init); module_exit(sdio_uart_exit); MODULE_AUTHOR("Nicolas Pitre"); MODULE_LICENSE("GPL");