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path: root/drivers/tty/serial/amba-pl010.c
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-rw-r--r--drivers/tty/serial/amba-pl010.c825
1 files changed, 825 insertions, 0 deletions
diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl010.c
new file mode 100644
index 000000000..af27fb8ec
--- /dev/null
+++ b/drivers/tty/serial/amba-pl010.c
@@ -0,0 +1,825 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Driver for AMBA serial ports
+ *
+ * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
+ *
+ * Copyright 1999 ARM Limited
+ * Copyright (C) 2000 Deep Blue Solutions Ltd.
+ *
+ * This is a generic driver for ARM AMBA-type serial ports. They
+ * have a lot of 16550-like features, but are not register compatible.
+ * Note that although they do have CTS, DCD and DSR inputs, they do
+ * not have an RI input, nor do they have DTR or RTS outputs. If
+ * required, these have to be supplied via some other means (eg, GPIO)
+ * and hooked into this driver.
+ */
+
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/device.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/amba/bus.h>
+#include <linux/amba/serial.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+
+#define UART_NR 8
+
+#define SERIAL_AMBA_MAJOR 204
+#define SERIAL_AMBA_MINOR 16
+#define SERIAL_AMBA_NR UART_NR
+
+#define AMBA_ISR_PASS_LIMIT 256
+
+#define UART_RX_DATA(s) (((s) & UART01x_FR_RXFE) == 0)
+#define UART_TX_READY(s) (((s) & UART01x_FR_TXFF) == 0)
+
+#define UART_DUMMY_RSR_RX 256
+#define UART_PORT_SIZE 64
+
+/*
+ * We wrap our port structure around the generic uart_port.
+ */
+struct uart_amba_port {
+ struct uart_port port;
+ struct clk *clk;
+ struct amba_device *dev;
+ struct amba_pl010_data *data;
+ unsigned int old_status;
+};
+
+static void pl010_stop_tx(struct uart_port *port)
+{
+ struct uart_amba_port *uap =
+ container_of(port, struct uart_amba_port, port);
+ unsigned int cr;
+
+ cr = readb(uap->port.membase + UART010_CR);
+ cr &= ~UART010_CR_TIE;
+ writel(cr, uap->port.membase + UART010_CR);
+}
+
+static void pl010_start_tx(struct uart_port *port)
+{
+ struct uart_amba_port *uap =
+ container_of(port, struct uart_amba_port, port);
+ unsigned int cr;
+
+ cr = readb(uap->port.membase + UART010_CR);
+ cr |= UART010_CR_TIE;
+ writel(cr, uap->port.membase + UART010_CR);
+}
+
+static void pl010_stop_rx(struct uart_port *port)
+{
+ struct uart_amba_port *uap =
+ container_of(port, struct uart_amba_port, port);
+ unsigned int cr;
+
+ cr = readb(uap->port.membase + UART010_CR);
+ cr &= ~(UART010_CR_RIE | UART010_CR_RTIE);
+ writel(cr, uap->port.membase + UART010_CR);
+}
+
+static void pl010_disable_ms(struct uart_port *port)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+ unsigned int cr;
+
+ cr = readb(uap->port.membase + UART010_CR);
+ cr &= ~UART010_CR_MSIE;
+ writel(cr, uap->port.membase + UART010_CR);
+}
+
+static void pl010_enable_ms(struct uart_port *port)
+{
+ struct uart_amba_port *uap =
+ container_of(port, struct uart_amba_port, port);
+ unsigned int cr;
+
+ cr = readb(uap->port.membase + UART010_CR);
+ cr |= UART010_CR_MSIE;
+ writel(cr, uap->port.membase + UART010_CR);
+}
+
+static void pl010_rx_chars(struct uart_port *port)
+{
+ unsigned int status, ch, flag, rsr, max_count = 256;
+
+ status = readb(port->membase + UART01x_FR);
+ while (UART_RX_DATA(status) && max_count--) {
+ ch = readb(port->membase + UART01x_DR);
+ flag = TTY_NORMAL;
+
+ port->icount.rx++;
+
+ /*
+ * Note that the error handling code is
+ * out of the main execution path
+ */
+ rsr = readb(port->membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
+ if (unlikely(rsr & UART01x_RSR_ANY)) {
+ writel(0, port->membase + UART01x_ECR);
+
+ if (rsr & UART01x_RSR_BE) {
+ rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
+ port->icount.brk++;
+ if (uart_handle_break(port))
+ goto ignore_char;
+ } else if (rsr & UART01x_RSR_PE)
+ port->icount.parity++;
+ else if (rsr & UART01x_RSR_FE)
+ port->icount.frame++;
+ if (rsr & UART01x_RSR_OE)
+ port->icount.overrun++;
+
+ rsr &= port->read_status_mask;
+
+ if (rsr & UART01x_RSR_BE)
+ flag = TTY_BREAK;
+ else if (rsr & UART01x_RSR_PE)
+ flag = TTY_PARITY;
+ else if (rsr & UART01x_RSR_FE)
+ flag = TTY_FRAME;
+ }
+
+ if (uart_handle_sysrq_char(port, ch))
+ goto ignore_char;
+
+ uart_insert_char(port, rsr, UART01x_RSR_OE, ch, flag);
+
+ ignore_char:
+ status = readb(port->membase + UART01x_FR);
+ }
+ tty_flip_buffer_push(&port->state->port);
+}
+
+static void pl010_tx_chars(struct uart_port *port)
+{
+ struct circ_buf *xmit = &port->state->xmit;
+ int count;
+
+ if (port->x_char) {
+ writel(port->x_char, port->membase + UART01x_DR);
+ port->icount.tx++;
+ port->x_char = 0;
+ return;
+ }
+ if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+ pl010_stop_tx(port);
+ return;
+ }
+
+ count = port->fifosize >> 1;
+ do {
+ writel(xmit->buf[xmit->tail], port->membase + UART01x_DR);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ port->icount.tx++;
+ if (uart_circ_empty(xmit))
+ break;
+ } while (--count > 0);
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+
+ if (uart_circ_empty(xmit))
+ pl010_stop_tx(port);
+}
+
+static void pl010_modem_status(struct uart_amba_port *uap)
+{
+ struct uart_port *port = &uap->port;
+ unsigned int status, delta;
+
+ writel(0, port->membase + UART010_ICR);
+
+ status = readb(port->membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
+
+ delta = status ^ uap->old_status;
+ uap->old_status = status;
+
+ if (!delta)
+ return;
+
+ if (delta & UART01x_FR_DCD)
+ uart_handle_dcd_change(port, status & UART01x_FR_DCD);
+
+ if (delta & UART01x_FR_DSR)
+ port->icount.dsr++;
+
+ if (delta & UART01x_FR_CTS)
+ uart_handle_cts_change(port, status & UART01x_FR_CTS);
+
+ wake_up_interruptible(&port->state->port.delta_msr_wait);
+}
+
+static irqreturn_t pl010_int(int irq, void *dev_id)
+{
+ struct uart_amba_port *uap = dev_id;
+ struct uart_port *port = &uap->port;
+ unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
+ int handled = 0;
+
+ spin_lock(&port->lock);
+
+ status = readb(port->membase + UART010_IIR);
+ if (status) {
+ do {
+ if (status & (UART010_IIR_RTIS | UART010_IIR_RIS))
+ pl010_rx_chars(port);
+ if (status & UART010_IIR_MIS)
+ pl010_modem_status(uap);
+ if (status & UART010_IIR_TIS)
+ pl010_tx_chars(port);
+
+ if (pass_counter-- == 0)
+ break;
+
+ status = readb(port->membase + UART010_IIR);
+ } while (status & (UART010_IIR_RTIS | UART010_IIR_RIS |
+ UART010_IIR_TIS));
+ handled = 1;
+ }
+
+ spin_unlock(&port->lock);
+
+ return IRQ_RETVAL(handled);
+}
+
+static unsigned int pl010_tx_empty(struct uart_port *port)
+{
+ unsigned int status = readb(port->membase + UART01x_FR);
+
+ return status & UART01x_FR_BUSY ? 0 : TIOCSER_TEMT;
+}
+
+static unsigned int pl010_get_mctrl(struct uart_port *port)
+{
+ unsigned int result = 0;
+ unsigned int status;
+
+ status = readb(port->membase + UART01x_FR);
+ if (status & UART01x_FR_DCD)
+ result |= TIOCM_CAR;
+ if (status & UART01x_FR_DSR)
+ result |= TIOCM_DSR;
+ if (status & UART01x_FR_CTS)
+ result |= TIOCM_CTS;
+
+ return result;
+}
+
+static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ struct uart_amba_port *uap =
+ container_of(port, struct uart_amba_port, port);
+
+ if (uap->data)
+ uap->data->set_mctrl(uap->dev, port->membase, mctrl);
+}
+
+static void pl010_break_ctl(struct uart_port *port, int break_state)
+{
+ unsigned long flags;
+ unsigned int lcr_h;
+
+ spin_lock_irqsave(&port->lock, flags);
+ lcr_h = readb(port->membase + UART010_LCRH);
+ if (break_state == -1)
+ lcr_h |= UART01x_LCRH_BRK;
+ else
+ lcr_h &= ~UART01x_LCRH_BRK;
+ writel(lcr_h, port->membase + UART010_LCRH);
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static int pl010_startup(struct uart_port *port)
+{
+ struct uart_amba_port *uap =
+ container_of(port, struct uart_amba_port, port);
+ int retval;
+
+ /*
+ * Try to enable the clock producer.
+ */
+ retval = clk_prepare_enable(uap->clk);
+ if (retval)
+ goto out;
+
+ port->uartclk = clk_get_rate(uap->clk);
+
+ /*
+ * Allocate the IRQ
+ */
+ retval = request_irq(port->irq, pl010_int, 0, "uart-pl010", uap);
+ if (retval)
+ goto clk_dis;
+
+ /*
+ * initialise the old status of the modem signals
+ */
+ uap->old_status = readb(port->membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
+
+ /*
+ * Finally, enable interrupts
+ */
+ writel(UART01x_CR_UARTEN | UART010_CR_RIE | UART010_CR_RTIE,
+ port->membase + UART010_CR);
+
+ return 0;
+
+ clk_dis:
+ clk_disable_unprepare(uap->clk);
+ out:
+ return retval;
+}
+
+static void pl010_shutdown(struct uart_port *port)
+{
+ struct uart_amba_port *uap =
+ container_of(port, struct uart_amba_port, port);
+
+ /*
+ * Free the interrupt
+ */
+ free_irq(port->irq, uap);
+
+ /*
+ * disable all interrupts, disable the port
+ */
+ writel(0, port->membase + UART010_CR);
+
+ /* disable break condition and fifos */
+ writel(readb(port->membase + UART010_LCRH) &
+ ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN),
+ port->membase + UART010_LCRH);
+
+ /*
+ * Shut down the clock producer
+ */
+ clk_disable_unprepare(uap->clk);
+}
+
+static void
+pl010_set_termios(struct uart_port *port, struct ktermios *termios,
+ const struct ktermios *old)
+{
+ unsigned int lcr_h, old_cr;
+ unsigned long flags;
+ unsigned int baud, quot;
+
+ /*
+ * Ask the core to calculate the divisor for us.
+ */
+ baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
+ quot = uart_get_divisor(port, baud);
+
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ lcr_h = UART01x_LCRH_WLEN_5;
+ break;
+ case CS6:
+ lcr_h = UART01x_LCRH_WLEN_6;
+ break;
+ case CS7:
+ lcr_h = UART01x_LCRH_WLEN_7;
+ break;
+ default: // CS8
+ lcr_h = UART01x_LCRH_WLEN_8;
+ break;
+ }
+ if (termios->c_cflag & CSTOPB)
+ lcr_h |= UART01x_LCRH_STP2;
+ if (termios->c_cflag & PARENB) {
+ lcr_h |= UART01x_LCRH_PEN;
+ if (!(termios->c_cflag & PARODD))
+ lcr_h |= UART01x_LCRH_EPS;
+ }
+ if (port->fifosize > 1)
+ lcr_h |= UART01x_LCRH_FEN;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /*
+ * Update the per-port timeout.
+ */
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ port->read_status_mask = UART01x_RSR_OE;
+ if (termios->c_iflag & INPCK)
+ port->read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
+ if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
+ port->read_status_mask |= UART01x_RSR_BE;
+
+ /*
+ * Characters to ignore
+ */
+ port->ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
+ if (termios->c_iflag & IGNBRK) {
+ port->ignore_status_mask |= UART01x_RSR_BE;
+ /*
+ * If we're ignoring parity and break indicators,
+ * ignore overruns too (for real raw support).
+ */
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= UART01x_RSR_OE;
+ }
+
+ /*
+ * Ignore all characters if CREAD is not set.
+ */
+ if ((termios->c_cflag & CREAD) == 0)
+ port->ignore_status_mask |= UART_DUMMY_RSR_RX;
+
+ old_cr = readb(port->membase + UART010_CR) & ~UART010_CR_MSIE;
+
+ if (UART_ENABLE_MS(port, termios->c_cflag))
+ old_cr |= UART010_CR_MSIE;
+
+ /* Set baud rate */
+ quot -= 1;
+ writel((quot & 0xf00) >> 8, port->membase + UART010_LCRM);
+ writel(quot & 0xff, port->membase + UART010_LCRL);
+
+ /*
+ * ----------v----------v----------v----------v-----
+ * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
+ * ----------^----------^----------^----------^-----
+ */
+ writel(lcr_h, port->membase + UART010_LCRH);
+ writel(old_cr, port->membase + UART010_CR);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void pl010_set_ldisc(struct uart_port *port, struct ktermios *termios)
+{
+ if (termios->c_line == N_PPS) {
+ port->flags |= UPF_HARDPPS_CD;
+ spin_lock_irq(&port->lock);
+ pl010_enable_ms(port);
+ spin_unlock_irq(&port->lock);
+ } else {
+ port->flags &= ~UPF_HARDPPS_CD;
+ if (!UART_ENABLE_MS(port, termios->c_cflag)) {
+ spin_lock_irq(&port->lock);
+ pl010_disable_ms(port);
+ spin_unlock_irq(&port->lock);
+ }
+ }
+}
+
+static const char *pl010_type(struct uart_port *port)
+{
+ return port->type == PORT_AMBA ? "AMBA" : NULL;
+}
+
+/*
+ * Release the memory region(s) being used by 'port'
+ */
+static void pl010_release_port(struct uart_port *port)
+{
+ release_mem_region(port->mapbase, UART_PORT_SIZE);
+}
+
+/*
+ * Request the memory region(s) being used by 'port'
+ */
+static int pl010_request_port(struct uart_port *port)
+{
+ return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010")
+ != NULL ? 0 : -EBUSY;
+}
+
+/*
+ * Configure/autoconfigure the port.
+ */
+static void pl010_config_port(struct uart_port *port, int flags)
+{
+ if (flags & UART_CONFIG_TYPE) {
+ port->type = PORT_AMBA;
+ pl010_request_port(port);
+ }
+}
+
+/*
+ * verify the new serial_struct (for TIOCSSERIAL).
+ */
+static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+ int ret = 0;
+ if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
+ ret = -EINVAL;
+ if (ser->irq < 0 || ser->irq >= nr_irqs)
+ ret = -EINVAL;
+ if (ser->baud_base < 9600)
+ ret = -EINVAL;
+ return ret;
+}
+
+static const struct uart_ops amba_pl010_pops = {
+ .tx_empty = pl010_tx_empty,
+ .set_mctrl = pl010_set_mctrl,
+ .get_mctrl = pl010_get_mctrl,
+ .stop_tx = pl010_stop_tx,
+ .start_tx = pl010_start_tx,
+ .stop_rx = pl010_stop_rx,
+ .enable_ms = pl010_enable_ms,
+ .break_ctl = pl010_break_ctl,
+ .startup = pl010_startup,
+ .shutdown = pl010_shutdown,
+ .set_termios = pl010_set_termios,
+ .set_ldisc = pl010_set_ldisc,
+ .type = pl010_type,
+ .release_port = pl010_release_port,
+ .request_port = pl010_request_port,
+ .config_port = pl010_config_port,
+ .verify_port = pl010_verify_port,
+};
+
+static struct uart_amba_port *amba_ports[UART_NR];
+
+#ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
+
+static void pl010_console_putchar(struct uart_port *port, unsigned char ch)
+{
+ unsigned int status;
+
+ do {
+ status = readb(port->membase + UART01x_FR);
+ barrier();
+ } while (!UART_TX_READY(status));
+ writel(ch, port->membase + UART01x_DR);
+}
+
+static void
+pl010_console_write(struct console *co, const char *s, unsigned int count)
+{
+ struct uart_amba_port *uap = amba_ports[co->index];
+ struct uart_port *port = &uap->port;
+ unsigned int status, old_cr;
+
+ clk_enable(uap->clk);
+
+ /*
+ * First save the CR then disable the interrupts
+ */
+ old_cr = readb(port->membase + UART010_CR);
+ writel(UART01x_CR_UARTEN, port->membase + UART010_CR);
+
+ uart_console_write(port, s, count, pl010_console_putchar);
+
+ /*
+ * Finally, wait for transmitter to become empty
+ * and restore the TCR
+ */
+ do {
+ status = readb(port->membase + UART01x_FR);
+ barrier();
+ } while (status & UART01x_FR_BUSY);
+ writel(old_cr, port->membase + UART010_CR);
+
+ clk_disable(uap->clk);
+}
+
+static void __init
+pl010_console_get_options(struct uart_amba_port *uap, int *baud,
+ int *parity, int *bits)
+{
+ if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) {
+ unsigned int lcr_h, quot;
+ lcr_h = readb(uap->port.membase + UART010_LCRH);
+
+ *parity = 'n';
+ if (lcr_h & UART01x_LCRH_PEN) {
+ if (lcr_h & UART01x_LCRH_EPS)
+ *parity = 'e';
+ else
+ *parity = 'o';
+ }
+
+ if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
+ *bits = 7;
+ else
+ *bits = 8;
+
+ quot = readb(uap->port.membase + UART010_LCRL) |
+ readb(uap->port.membase + UART010_LCRM) << 8;
+ *baud = uap->port.uartclk / (16 * (quot + 1));
+ }
+}
+
+static int __init pl010_console_setup(struct console *co, char *options)
+{
+ struct uart_amba_port *uap;
+ int baud = 38400;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+ int ret;
+
+ /*
+ * Check whether an invalid uart number has been specified, and
+ * if so, search for the first available port that does have
+ * console support.
+ */
+ if (co->index >= UART_NR)
+ co->index = 0;
+ uap = amba_ports[co->index];
+ if (!uap)
+ return -ENODEV;
+
+ ret = clk_prepare(uap->clk);
+ if (ret)
+ return ret;
+
+ uap->port.uartclk = clk_get_rate(uap->clk);
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+ else
+ pl010_console_get_options(uap, &baud, &parity, &bits);
+
+ return uart_set_options(&uap->port, co, baud, parity, bits, flow);
+}
+
+static struct uart_driver amba_reg;
+static struct console amba_console = {
+ .name = "ttyAM",
+ .write = pl010_console_write,
+ .device = uart_console_device,
+ .setup = pl010_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &amba_reg,
+};
+
+#define AMBA_CONSOLE &amba_console
+#else
+#define AMBA_CONSOLE NULL
+#endif
+
+static DEFINE_MUTEX(amba_reg_lock);
+static struct uart_driver amba_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = "ttyAM",
+ .dev_name = "ttyAM",
+ .major = SERIAL_AMBA_MAJOR,
+ .minor = SERIAL_AMBA_MINOR,
+ .nr = UART_NR,
+ .cons = AMBA_CONSOLE,
+};
+
+static int pl010_probe(struct amba_device *dev, const struct amba_id *id)
+{
+ struct uart_amba_port *uap;
+ void __iomem *base;
+ int i, ret;
+
+ for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
+ if (amba_ports[i] == NULL)
+ break;
+
+ if (i == ARRAY_SIZE(amba_ports))
+ return -EBUSY;
+
+ uap = devm_kzalloc(&dev->dev, sizeof(struct uart_amba_port),
+ GFP_KERNEL);
+ if (!uap)
+ return -ENOMEM;
+
+ base = devm_ioremap(&dev->dev, dev->res.start,
+ resource_size(&dev->res));
+ if (!base)
+ return -ENOMEM;
+
+ uap->clk = devm_clk_get(&dev->dev, NULL);
+ if (IS_ERR(uap->clk))
+ return PTR_ERR(uap->clk);
+
+ uap->port.dev = &dev->dev;
+ uap->port.mapbase = dev->res.start;
+ uap->port.membase = base;
+ uap->port.iotype = UPIO_MEM;
+ uap->port.irq = dev->irq[0];
+ uap->port.fifosize = 16;
+ uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_AMBA_PL010_CONSOLE);
+ uap->port.ops = &amba_pl010_pops;
+ uap->port.flags = UPF_BOOT_AUTOCONF;
+ uap->port.line = i;
+ uap->dev = dev;
+ uap->data = dev_get_platdata(&dev->dev);
+
+ amba_ports[i] = uap;
+
+ amba_set_drvdata(dev, uap);
+
+ mutex_lock(&amba_reg_lock);
+ if (!amba_reg.state) {
+ ret = uart_register_driver(&amba_reg);
+ if (ret < 0) {
+ mutex_unlock(&amba_reg_lock);
+ dev_err(uap->port.dev,
+ "Failed to register AMBA-PL010 driver\n");
+ return ret;
+ }
+ }
+ mutex_unlock(&amba_reg_lock);
+
+ ret = uart_add_one_port(&amba_reg, &uap->port);
+ if (ret)
+ amba_ports[i] = NULL;
+
+ return ret;
+}
+
+static void pl010_remove(struct amba_device *dev)
+{
+ struct uart_amba_port *uap = amba_get_drvdata(dev);
+ int i;
+ bool busy = false;
+
+ uart_remove_one_port(&amba_reg, &uap->port);
+
+ for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
+ if (amba_ports[i] == uap)
+ amba_ports[i] = NULL;
+ else if (amba_ports[i])
+ busy = true;
+
+ if (!busy)
+ uart_unregister_driver(&amba_reg);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int pl010_suspend(struct device *dev)
+{
+ struct uart_amba_port *uap = dev_get_drvdata(dev);
+
+ if (uap)
+ uart_suspend_port(&amba_reg, &uap->port);
+
+ return 0;
+}
+
+static int pl010_resume(struct device *dev)
+{
+ struct uart_amba_port *uap = dev_get_drvdata(dev);
+
+ if (uap)
+ uart_resume_port(&amba_reg, &uap->port);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(pl010_dev_pm_ops, pl010_suspend, pl010_resume);
+
+static const struct amba_id pl010_ids[] = {
+ {
+ .id = 0x00041010,
+ .mask = 0x000fffff,
+ },
+ { 0, 0 },
+};
+
+MODULE_DEVICE_TABLE(amba, pl010_ids);
+
+static struct amba_driver pl010_driver = {
+ .drv = {
+ .name = "uart-pl010",
+ .pm = &pl010_dev_pm_ops,
+ },
+ .id_table = pl010_ids,
+ .probe = pl010_probe,
+ .remove = pl010_remove,
+};
+
+static int __init pl010_init(void)
+{
+ printk(KERN_INFO "Serial: AMBA driver\n");
+
+ return amba_driver_register(&pl010_driver);
+}
+
+static void __exit pl010_exit(void)
+{
+ amba_driver_unregister(&pl010_driver);
+}
+
+module_init(pl010_init);
+module_exit(pl010_exit);
+
+MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
+MODULE_DESCRIPTION("ARM AMBA serial port driver");
+MODULE_LICENSE("GPL");