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![Greg Kroah-Hartman](/assets/img/avatar_default.png)
Now that the SPDX tag is in all tty files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Jiri Slaby <jslaby@suse.com> Cc: Eric Anholt <eric@anholt.net> Cc: Stefan Wahren <stefan.wahren@i2se.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Ray Jui <rjui@broadcom.com> Cc: Scott Branden <sbranden@broadcom.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Joachim Eastwood <manabian@gmail.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: Pat Gefre <pfg@sgi.com> Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Sylvain Lemieux <slemieux.tyco@gmail.com> Cc: Carlo Caione <carlo@caione.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Andy Gross <andy.gross@linaro.org> Cc: David Brown <david.brown@linaro.org> Cc: "Andreas Färber" <afaerber@suse.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Laxman Dewangan <ldewangan@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Barry Song <baohua@kernel.org> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Peter Korsgaard <jacmet@sunsite.dk> Cc: Timur Tabi <timur@tabi.org> Cc: Tony Prisk <linux@prisktech.co.nz> Cc: Michal Simek <michal.simek@xilinx.com> Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
504 lines
12 KiB
C
504 lines
12 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* timbuart.c timberdale FPGA UART driver
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* Copyright (c) 2009 Intel Corporation
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*/
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/* Supports:
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* Timberdale FPGA UART
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*/
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#include <linux/pci.h>
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#include <linux/interrupt.h>
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#include <linux/serial_core.h>
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#include <linux/tty.h>
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#include <linux/tty_flip.h>
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#include <linux/kernel.h>
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#include <linux/platform_device.h>
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#include <linux/ioport.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include "timbuart.h"
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struct timbuart_port {
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struct uart_port port;
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struct tasklet_struct tasklet;
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int usedma;
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u32 last_ier;
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struct platform_device *dev;
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};
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static int baudrates[] = {9600, 19200, 38400, 57600, 115200, 230400, 460800,
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921600, 1843200, 3250000};
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static void timbuart_mctrl_check(struct uart_port *port, u32 isr, u32 *ier);
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static irqreturn_t timbuart_handleinterrupt(int irq, void *devid);
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static void timbuart_stop_rx(struct uart_port *port)
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{
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/* spin lock held by upper layer, disable all RX interrupts */
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u32 ier = ioread32(port->membase + TIMBUART_IER) & ~RXFLAGS;
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iowrite32(ier, port->membase + TIMBUART_IER);
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}
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static void timbuart_stop_tx(struct uart_port *port)
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{
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/* spinlock held by upper layer, disable TX interrupt */
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u32 ier = ioread32(port->membase + TIMBUART_IER) & ~TXBAE;
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iowrite32(ier, port->membase + TIMBUART_IER);
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}
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static void timbuart_start_tx(struct uart_port *port)
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{
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struct timbuart_port *uart =
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container_of(port, struct timbuart_port, port);
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/* do not transfer anything here -> fire off the tasklet */
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tasklet_schedule(&uart->tasklet);
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}
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static unsigned int timbuart_tx_empty(struct uart_port *port)
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{
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u32 isr = ioread32(port->membase + TIMBUART_ISR);
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return (isr & TXBE) ? TIOCSER_TEMT : 0;
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}
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static void timbuart_flush_buffer(struct uart_port *port)
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{
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if (!timbuart_tx_empty(port)) {
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u8 ctl = ioread8(port->membase + TIMBUART_CTRL) |
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TIMBUART_CTRL_FLSHTX;
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iowrite8(ctl, port->membase + TIMBUART_CTRL);
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iowrite32(TXBF, port->membase + TIMBUART_ISR);
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}
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}
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static void timbuart_rx_chars(struct uart_port *port)
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{
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struct tty_port *tport = &port->state->port;
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while (ioread32(port->membase + TIMBUART_ISR) & RXDP) {
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u8 ch = ioread8(port->membase + TIMBUART_RXFIFO);
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port->icount.rx++;
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tty_insert_flip_char(tport, ch, TTY_NORMAL);
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}
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spin_unlock(&port->lock);
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tty_flip_buffer_push(tport);
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spin_lock(&port->lock);
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dev_dbg(port->dev, "%s - total read %d bytes\n",
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__func__, port->icount.rx);
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}
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static void timbuart_tx_chars(struct uart_port *port)
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{
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struct circ_buf *xmit = &port->state->xmit;
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while (!(ioread32(port->membase + TIMBUART_ISR) & TXBF) &&
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!uart_circ_empty(xmit)) {
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iowrite8(xmit->buf[xmit->tail],
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port->membase + TIMBUART_TXFIFO);
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xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
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port->icount.tx++;
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}
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dev_dbg(port->dev,
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"%s - total written %d bytes, CTL: %x, RTS: %x, baud: %x\n",
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__func__,
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port->icount.tx,
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ioread8(port->membase + TIMBUART_CTRL),
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port->mctrl & TIOCM_RTS,
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ioread8(port->membase + TIMBUART_BAUDRATE));
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}
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static void timbuart_handle_tx_port(struct uart_port *port, u32 isr, u32 *ier)
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{
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struct timbuart_port *uart =
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container_of(port, struct timbuart_port, port);
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struct circ_buf *xmit = &port->state->xmit;
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if (uart_circ_empty(xmit) || uart_tx_stopped(port))
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return;
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if (port->x_char)
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return;
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if (isr & TXFLAGS) {
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timbuart_tx_chars(port);
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/* clear all TX interrupts */
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iowrite32(TXFLAGS, port->membase + TIMBUART_ISR);
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if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
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uart_write_wakeup(port);
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} else
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/* Re-enable any tx interrupt */
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*ier |= uart->last_ier & TXFLAGS;
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/* enable interrupts if there are chars in the transmit buffer,
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* Or if we delivered some bytes and want the almost empty interrupt
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* we wake up the upper layer later when we got the interrupt
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* to give it some time to go out...
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*/
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if (!uart_circ_empty(xmit))
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*ier |= TXBAE;
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dev_dbg(port->dev, "%s - leaving\n", __func__);
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}
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static void timbuart_handle_rx_port(struct uart_port *port, u32 isr, u32 *ier)
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{
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if (isr & RXFLAGS) {
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/* Some RX status is set */
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if (isr & RXBF) {
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u8 ctl = ioread8(port->membase + TIMBUART_CTRL) |
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TIMBUART_CTRL_FLSHRX;
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iowrite8(ctl, port->membase + TIMBUART_CTRL);
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port->icount.overrun++;
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} else if (isr & (RXDP))
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timbuart_rx_chars(port);
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/* ack all RX interrupts */
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iowrite32(RXFLAGS, port->membase + TIMBUART_ISR);
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}
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/* always have the RX interrupts enabled */
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*ier |= RXBAF | RXBF | RXTT;
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dev_dbg(port->dev, "%s - leaving\n", __func__);
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}
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static void timbuart_tasklet(unsigned long arg)
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{
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struct timbuart_port *uart = (struct timbuart_port *)arg;
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u32 isr, ier = 0;
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spin_lock(&uart->port.lock);
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isr = ioread32(uart->port.membase + TIMBUART_ISR);
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dev_dbg(uart->port.dev, "%s ISR: %x\n", __func__, isr);
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if (!uart->usedma)
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timbuart_handle_tx_port(&uart->port, isr, &ier);
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timbuart_mctrl_check(&uart->port, isr, &ier);
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if (!uart->usedma)
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timbuart_handle_rx_port(&uart->port, isr, &ier);
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iowrite32(ier, uart->port.membase + TIMBUART_IER);
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spin_unlock(&uart->port.lock);
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dev_dbg(uart->port.dev, "%s leaving\n", __func__);
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}
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static unsigned int timbuart_get_mctrl(struct uart_port *port)
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{
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u8 cts = ioread8(port->membase + TIMBUART_CTRL);
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dev_dbg(port->dev, "%s - cts %x\n", __func__, cts);
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if (cts & TIMBUART_CTRL_CTS)
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return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
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else
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return TIOCM_DSR | TIOCM_CAR;
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}
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static void timbuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
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{
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dev_dbg(port->dev, "%s - %x\n", __func__, mctrl);
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if (mctrl & TIOCM_RTS)
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iowrite8(TIMBUART_CTRL_RTS, port->membase + TIMBUART_CTRL);
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else
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iowrite8(0, port->membase + TIMBUART_CTRL);
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}
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static void timbuart_mctrl_check(struct uart_port *port, u32 isr, u32 *ier)
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{
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unsigned int cts;
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if (isr & CTS_DELTA) {
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/* ack */
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iowrite32(CTS_DELTA, port->membase + TIMBUART_ISR);
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cts = timbuart_get_mctrl(port);
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uart_handle_cts_change(port, cts & TIOCM_CTS);
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wake_up_interruptible(&port->state->port.delta_msr_wait);
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}
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*ier |= CTS_DELTA;
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}
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static void timbuart_break_ctl(struct uart_port *port, int ctl)
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{
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/* N/A */
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}
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static int timbuart_startup(struct uart_port *port)
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{
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struct timbuart_port *uart =
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container_of(port, struct timbuart_port, port);
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dev_dbg(port->dev, "%s\n", __func__);
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iowrite8(TIMBUART_CTRL_FLSHRX, port->membase + TIMBUART_CTRL);
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iowrite32(0x1ff, port->membase + TIMBUART_ISR);
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/* Enable all but TX interrupts */
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iowrite32(RXBAF | RXBF | RXTT | CTS_DELTA,
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port->membase + TIMBUART_IER);
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return request_irq(port->irq, timbuart_handleinterrupt, IRQF_SHARED,
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"timb-uart", uart);
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}
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static void timbuart_shutdown(struct uart_port *port)
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{
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struct timbuart_port *uart =
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container_of(port, struct timbuart_port, port);
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dev_dbg(port->dev, "%s\n", __func__);
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free_irq(port->irq, uart);
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iowrite32(0, port->membase + TIMBUART_IER);
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timbuart_flush_buffer(port);
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}
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static int get_bindex(int baud)
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{
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int i;
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for (i = 0; i < ARRAY_SIZE(baudrates); i++)
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if (baud <= baudrates[i])
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return i;
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return -1;
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}
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static void timbuart_set_termios(struct uart_port *port,
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struct ktermios *termios,
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struct ktermios *old)
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{
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unsigned int baud;
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short bindex;
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unsigned long flags;
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baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
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bindex = get_bindex(baud);
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dev_dbg(port->dev, "%s - bindex %d\n", __func__, bindex);
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if (bindex < 0)
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bindex = 0;
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baud = baudrates[bindex];
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/* The serial layer calls into this once with old = NULL when setting
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up initially */
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if (old)
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tty_termios_copy_hw(termios, old);
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tty_termios_encode_baud_rate(termios, baud, baud);
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spin_lock_irqsave(&port->lock, flags);
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iowrite8((u8)bindex, port->membase + TIMBUART_BAUDRATE);
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uart_update_timeout(port, termios->c_cflag, baud);
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spin_unlock_irqrestore(&port->lock, flags);
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}
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static const char *timbuart_type(struct uart_port *port)
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{
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return port->type == PORT_UNKNOWN ? "timbuart" : NULL;
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}
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/* We do not request/release mappings of the registers here,
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* currently it's done in the proble function.
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*/
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static void timbuart_release_port(struct uart_port *port)
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{
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struct platform_device *pdev = to_platform_device(port->dev);
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int size =
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resource_size(platform_get_resource(pdev, IORESOURCE_MEM, 0));
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if (port->flags & UPF_IOREMAP) {
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iounmap(port->membase);
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port->membase = NULL;
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}
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release_mem_region(port->mapbase, size);
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}
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static int timbuart_request_port(struct uart_port *port)
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{
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struct platform_device *pdev = to_platform_device(port->dev);
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int size =
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resource_size(platform_get_resource(pdev, IORESOURCE_MEM, 0));
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if (!request_mem_region(port->mapbase, size, "timb-uart"))
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return -EBUSY;
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if (port->flags & UPF_IOREMAP) {
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port->membase = ioremap(port->mapbase, size);
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if (port->membase == NULL) {
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release_mem_region(port->mapbase, size);
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return -ENOMEM;
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}
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}
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return 0;
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}
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static irqreturn_t timbuart_handleinterrupt(int irq, void *devid)
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{
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struct timbuart_port *uart = (struct timbuart_port *)devid;
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if (ioread8(uart->port.membase + TIMBUART_IPR)) {
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uart->last_ier = ioread32(uart->port.membase + TIMBUART_IER);
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/* disable interrupts, the tasklet enables them again */
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iowrite32(0, uart->port.membase + TIMBUART_IER);
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/* fire off bottom half */
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tasklet_schedule(&uart->tasklet);
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return IRQ_HANDLED;
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} else
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return IRQ_NONE;
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}
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/*
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* Configure/autoconfigure the port.
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*/
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static void timbuart_config_port(struct uart_port *port, int flags)
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{
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if (flags & UART_CONFIG_TYPE) {
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port->type = PORT_TIMBUART;
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timbuart_request_port(port);
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}
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}
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static int timbuart_verify_port(struct uart_port *port,
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struct serial_struct *ser)
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{
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/* we don't want the core code to modify any port params */
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return -EINVAL;
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}
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static const struct uart_ops timbuart_ops = {
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.tx_empty = timbuart_tx_empty,
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.set_mctrl = timbuart_set_mctrl,
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.get_mctrl = timbuart_get_mctrl,
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.stop_tx = timbuart_stop_tx,
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.start_tx = timbuart_start_tx,
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.flush_buffer = timbuart_flush_buffer,
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.stop_rx = timbuart_stop_rx,
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.break_ctl = timbuart_break_ctl,
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.startup = timbuart_startup,
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.shutdown = timbuart_shutdown,
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.set_termios = timbuart_set_termios,
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.type = timbuart_type,
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.release_port = timbuart_release_port,
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.request_port = timbuart_request_port,
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.config_port = timbuart_config_port,
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.verify_port = timbuart_verify_port
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};
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static struct uart_driver timbuart_driver = {
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.owner = THIS_MODULE,
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.driver_name = "timberdale_uart",
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.dev_name = "ttyTU",
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.major = TIMBUART_MAJOR,
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.minor = TIMBUART_MINOR,
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.nr = 1
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};
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static int timbuart_probe(struct platform_device *dev)
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{
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int err, irq;
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struct timbuart_port *uart;
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struct resource *iomem;
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dev_dbg(&dev->dev, "%s\n", __func__);
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uart = kzalloc(sizeof(*uart), GFP_KERNEL);
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if (!uart) {
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err = -EINVAL;
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goto err_mem;
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}
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uart->usedma = 0;
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uart->port.uartclk = 3250000 * 16;
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uart->port.fifosize = TIMBUART_FIFO_SIZE;
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uart->port.regshift = 2;
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uart->port.iotype = UPIO_MEM;
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uart->port.ops = &timbuart_ops;
|
|
uart->port.irq = 0;
|
|
uart->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
|
|
uart->port.line = 0;
|
|
uart->port.dev = &dev->dev;
|
|
|
|
iomem = platform_get_resource(dev, IORESOURCE_MEM, 0);
|
|
if (!iomem) {
|
|
err = -ENOMEM;
|
|
goto err_register;
|
|
}
|
|
uart->port.mapbase = iomem->start;
|
|
uart->port.membase = NULL;
|
|
|
|
irq = platform_get_irq(dev, 0);
|
|
if (irq < 0) {
|
|
err = -EINVAL;
|
|
goto err_register;
|
|
}
|
|
uart->port.irq = irq;
|
|
|
|
tasklet_init(&uart->tasklet, timbuart_tasklet, (unsigned long)uart);
|
|
|
|
err = uart_register_driver(&timbuart_driver);
|
|
if (err)
|
|
goto err_register;
|
|
|
|
err = uart_add_one_port(&timbuart_driver, &uart->port);
|
|
if (err)
|
|
goto err_add_port;
|
|
|
|
platform_set_drvdata(dev, uart);
|
|
|
|
return 0;
|
|
|
|
err_add_port:
|
|
uart_unregister_driver(&timbuart_driver);
|
|
err_register:
|
|
kfree(uart);
|
|
err_mem:
|
|
printk(KERN_ERR "timberdale: Failed to register Timberdale UART: %d\n",
|
|
err);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int timbuart_remove(struct platform_device *dev)
|
|
{
|
|
struct timbuart_port *uart = platform_get_drvdata(dev);
|
|
|
|
tasklet_kill(&uart->tasklet);
|
|
uart_remove_one_port(&timbuart_driver, &uart->port);
|
|
uart_unregister_driver(&timbuart_driver);
|
|
kfree(uart);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver timbuart_platform_driver = {
|
|
.driver = {
|
|
.name = "timb-uart",
|
|
},
|
|
.probe = timbuart_probe,
|
|
.remove = timbuart_remove,
|
|
};
|
|
|
|
module_platform_driver(timbuart_platform_driver);
|
|
|
|
MODULE_DESCRIPTION("Timberdale UART driver");
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_ALIAS("platform:timb-uart");
|
|
|