[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / serial / timbuart.c

/*
 * timbuart.c timberdale FPGA UART driver
 * Copyright (c) 2009 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/* Supports:
 * Timberdale FPGA UART
 */

#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/serial_core.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/ioport.h>

#include "timbuart.h"

struct timbuart_port {
	struct uart_port	port;
	struct tasklet_struct	tasklet;
	int			usedma;
	u8			last_ier;
	struct platform_device  *dev;
};

static int baudrates[] = {9600, 19200, 38400, 57600, 115200, 230400, 460800,
	921600, 1843200, 3250000};

static void timbuart_mctrl_check(struct uart_port *port, u8 isr, u8 *ier);

static irqreturn_t timbuart_handleinterrupt(int irq, void *devid);

static void timbuart_stop_rx(struct uart_port *port)
{
	/* spin lock held by upper layer, disable all RX interrupts */
	u8 ier = ioread8(port->membase + TIMBUART_IER) & ~RXFLAGS;
	iowrite8(ier, port->membase + TIMBUART_IER);
}

static void timbuart_stop_tx(struct uart_port *port)
{
	/* spinlock held by upper layer, disable TX interrupt */
	u8 ier = ioread8(port->membase + TIMBUART_IER) & ~TXBAE;
	iowrite8(ier, port->membase + TIMBUART_IER);
}

static void timbuart_start_tx(struct uart_port *port)
{
	struct timbuart_port *uart =
		container_of(port, struct timbuart_port, port);

	/* do not transfer anything here -> fire off the tasklet */
	tasklet_schedule(&uart->tasklet);
}

static void timbuart_flush_buffer(struct uart_port *port)
{
	u8 ctl = ioread8(port->membase + TIMBUART_CTRL) | TIMBUART_CTRL_FLSHTX;

	iowrite8(ctl, port->membase + TIMBUART_CTRL);
	iowrite8(TXBF, port->membase + TIMBUART_ISR);
}

static void timbuart_rx_chars(struct uart_port *port)
{
	struct tty_struct *tty = port->info->port.tty;

	while (ioread8(port->membase + TIMBUART_ISR) & RXDP) {
		u8 ch = ioread8(port->membase + TIMBUART_RXFIFO);
		port->icount.rx++;
		tty_insert_flip_char(tty, ch, TTY_NORMAL);
	}

	spin_unlock(&port->lock);
	tty_flip_buffer_push(port->info->port.tty);
	spin_lock(&port->lock);

	dev_dbg(port->dev, "%s - total read %d bytes\n",
		__func__, port->icount.rx);
}

static void timbuart_tx_chars(struct uart_port *port)
{
	struct circ_buf *xmit = &port->info->xmit;

	while (!(ioread8(port->membase + TIMBUART_ISR) & TXBF) &&
		!uart_circ_empty(xmit)) {
		iowrite8(xmit->buf[xmit->tail],
			port->membase + TIMBUART_TXFIFO);
		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
		port->icount.tx++;
	}

	dev_dbg(port->dev,
		"%s - total written %d bytes, CTL: %x, RTS: %x, baud: %x\n",
		 __func__,
		port->icount.tx,
		ioread8(port->membase + TIMBUART_CTRL),
		port->mctrl & TIOCM_RTS,
		ioread8(port->membase + TIMBUART_BAUDRATE));
}

static void timbuart_handle_tx_port(struct uart_port *port, u8 isr, u8 *ier)
{
	struct timbuart_port *uart =
		container_of(port, struct timbuart_port, port);
	struct circ_buf *xmit = &port->info->xmit;

	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
		return;

	if (port->x_char)
		return;

	if (isr & TXFLAGS) {
		timbuart_tx_chars(port);
		/* clear all TX interrupts */
		iowrite8(TXFLAGS, port->membase + TIMBUART_ISR);

		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
			uart_write_wakeup(port);
	} else
		/* Re-enable any tx interrupt */
		*ier |= uart->last_ier & TXFLAGS;

	/* enable interrupts if there are chars in the transmit buffer,
	 * Or if we delivered some bytes and want the almost empty interrupt
	 * we wake up the upper layer later when we got the interrupt
	 * to give it some time to go out...
	 */
	if (!uart_circ_empty(xmit))
		*ier |= TXBAE;

	dev_dbg(port->dev, "%s - leaving\n", __func__);
}

void timbuart_handle_rx_port(struct uart_port *port, u8 isr, u8 *ier)
{
	if (isr & RXFLAGS) {
		/* Some RX status is set */
		if (isr & RXBF) {
			u8 ctl = ioread8(port->membase + TIMBUART_CTRL) |
				TIMBUART_CTRL_FLSHRX;
			iowrite8(ctl, port->membase + TIMBUART_CTRL);
			port->icount.overrun++;
		} else if (isr & (RXDP))
			timbuart_rx_chars(port);

		/* ack all RX interrupts */
		iowrite8(RXFLAGS, port->membase + TIMBUART_ISR);
	}

	/* always have the RX interrupts enabled */
	*ier |= RXBAF | RXBF | RXTT;

	dev_dbg(port->dev, "%s - leaving\n", __func__);
}

void timbuart_tasklet(unsigned long arg)
{
	struct timbuart_port *uart = (struct timbuart_port *)arg;
	u8 isr, ier = 0;

	spin_lock(&uart->port.lock);

	isr = ioread8(uart->port.membase + TIMBUART_ISR);
	dev_dbg(uart->port.dev, "%s ISR: %x\n", __func__, isr);

	if (!uart->usedma)
		timbuart_handle_tx_port(&uart->port, isr, &ier);

	timbuart_mctrl_check(&uart->port, isr, &ier);

	if (!uart->usedma)
		timbuart_handle_rx_port(&uart->port, isr, &ier);

	iowrite8(ier, uart->port.membase + TIMBUART_IER);

	spin_unlock(&uart->port.lock);
	dev_dbg(uart->port.dev, "%s leaving\n", __func__);
}

static unsigned int timbuart_tx_empty(struct uart_port *port)
{
	u8 isr = ioread8(port->membase + TIMBUART_ISR);

	return (isr & TXBAE) ? TIOCSER_TEMT : 0;
}

static unsigned int timbuart_get_mctrl(struct uart_port *port)
{
	u8 cts = ioread8(port->membase + TIMBUART_CTRL);
	dev_dbg(port->dev, "%s - cts %x\n", __func__, cts);

	if (cts & TIMBUART_CTRL_CTS)
		return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
	else
		return TIOCM_DSR | TIOCM_CAR;
}

static void timbuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
	dev_dbg(port->dev, "%s - %x\n", __func__, mctrl);

	if (mctrl & TIOCM_RTS)
		iowrite8(TIMBUART_CTRL_RTS, port->membase + TIMBUART_CTRL);
	else
		iowrite8(TIMBUART_CTRL_RTS, port->membase + TIMBUART_CTRL);
}

static void timbuart_mctrl_check(struct uart_port *port, u8 isr, u8 *ier)
{
	unsigned int cts;

	if (isr & CTS_DELTA) {
		/* ack */
		iowrite8(CTS_DELTA, port->membase + TIMBUART_ISR);
		cts = timbuart_get_mctrl(port);
		uart_handle_cts_change(port, cts & TIOCM_CTS);
		wake_up_interruptible(&port->info->delta_msr_wait);
	}

	*ier |= CTS_DELTA;
}

static void timbuart_enable_ms(struct uart_port *port)
{
	/* N/A */
}

static void timbuart_break_ctl(struct uart_port *port, int ctl)
{
	/* N/A */
}

static int timbuart_startup(struct uart_port *port)
{
	struct timbuart_port *uart =
		container_of(port, struct timbuart_port, port);

	dev_dbg(port->dev, "%s\n", __func__);

	iowrite8(TIMBUART_CTRL_FLSHRX, port->membase + TIMBUART_CTRL);
	iowrite8(0xff, port->membase + TIMBUART_ISR);
	/* Enable all but TX interrupts */
	iowrite8(RXBAF | RXBF | RXTT | CTS_DELTA,
		port->membase + TIMBUART_IER);

	return request_irq(port->irq, timbuart_handleinterrupt, IRQF_SHARED,
		"timb-uart", uart);
}

static void timbuart_shutdown(struct uart_port *port)
{
	struct timbuart_port *uart =
		container_of(port, struct timbuart_port, port);
	dev_dbg(port->dev, "%s\n", __func__);
	free_irq(port->irq, uart);
	iowrite8(0, port->membase + TIMBUART_IER);
}

static int get_bindex(int baud)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(baudrates); i++)
		if (baud == baudrates[i])
			return i;

	return -1;
}

static void timbuart_set_termios(struct uart_port *port,
	struct ktermios *termios,
	struct ktermios *old)
{
	unsigned int baud;
	short bindex;
	unsigned long flags;

	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
	bindex = get_bindex(baud);
	dev_dbg(port->dev, "%s - bindex %d\n", __func__, bindex);

	if (bindex < 0) {
		printk(KERN_ALERT "timbuart: Unsupported baud rate\n");
	} else {
		spin_lock_irqsave(&port->lock, flags);
		iowrite8((u8)bindex, port->membase + TIMBUART_BAUDRATE);
		uart_update_timeout(port, termios->c_cflag, baud);
		spin_unlock_irqrestore(&port->lock, flags);
	}
}

static const char *timbuart_type(struct uart_port *port)
{
	return port->type == PORT_UNKNOWN ? "timbuart" : NULL;
}

/* We do not request/release mappings of the registers here,
 * currently it's done in the proble function.
 */
static void timbuart_release_port(struct uart_port *port)
{
	struct platform_device *pdev = to_platform_device(port->dev);
	int size =
		resource_size(platform_get_resource(pdev, IORESOURCE_MEM, 0));

	if (port->flags & UPF_IOREMAP) {
		iounmap(port->membase);
		port->membase = NULL;
	}

	release_mem_region(port->mapbase, size);
}

static int timbuart_request_port(struct uart_port *port)
{
	struct platform_device *pdev = to_platform_device(port->dev);
	int size =
		resource_size(platform_get_resource(pdev, IORESOURCE_MEM, 0));

	if (!request_mem_region(port->mapbase, size, "timb-uart"))
		return -EBUSY;

	if (port->flags & UPF_IOREMAP) {
		port->membase = ioremap(port->mapbase, size);
		if (port->membase == NULL) {
			release_mem_region(port->mapbase, size);
			return -ENOMEM;
		}
	}

	return 0;
}

static irqreturn_t timbuart_handleinterrupt(int irq, void *devid)
{
	struct timbuart_port *uart = (struct timbuart_port *)devid;

	if (ioread8(uart->port.membase + TIMBUART_IPR)) {
		uart->last_ier = ioread8(uart->port.membase + TIMBUART_IER);

		/* disable interrupts, the tasklet enables them again */
		iowrite8(0, uart->port.membase + TIMBUART_IER);

		/* fire off bottom half */
		tasklet_schedule(&uart->tasklet);

		return IRQ_HANDLED;
	} else
		return IRQ_NONE;
}

/*
 * Configure/autoconfigure the port.
 */
static void timbuart_config_port(struct uart_port *port, int flags)
{
	if (flags & UART_CONFIG_TYPE) {
		port->type = PORT_TIMBUART;
		timbuart_request_port(port);
	}
}

static int timbuart_verify_port(struct uart_port *port,
	struct serial_struct *ser)
{
	/* we don't want the core code to modify any port params */
	return -EINVAL;
}

static struct uart_ops timbuart_ops = {
	.tx_empty = timbuart_tx_empty,
	.set_mctrl = timbuart_set_mctrl,
	.get_mctrl = timbuart_get_mctrl,
	.stop_tx = timbuart_stop_tx,
	.start_tx = timbuart_start_tx,
	.flush_buffer = timbuart_flush_buffer,
	.stop_rx = timbuart_stop_rx,
	.enable_ms = timbuart_enable_ms,
	.break_ctl = timbuart_break_ctl,
	.startup = timbuart_startup,
	.shutdown = timbuart_shutdown,
	.set_termios = timbuart_set_termios,
	.type = timbuart_type,
	.release_port = timbuart_release_port,
	.request_port = timbuart_request_port,
	.config_port = timbuart_config_port,
	.verify_port = timbuart_verify_port
};

static struct uart_driver timbuart_driver = {
	.owner = THIS_MODULE,
	.driver_name = "timberdale_uart",
	.dev_name = "ttyTU",
	.major = TIMBUART_MAJOR,
	.minor = TIMBUART_MINOR,
	.nr = 1
};

static int timbuart_probe(struct platform_device *dev)
{
	int err;
	struct timbuart_port *uart;
	struct resource *iomem;

	dev_dbg(&dev->dev, "%s\n", __func__);

	uart = kzalloc(sizeof(*uart), GFP_KERNEL);
	if (!uart) {
		err = -EINVAL;
		goto err_mem;
	}

	uart->usedma = 0;

	uart->port.uartclk = 3250000 * 16;
	uart->port.fifosize  = TIMBUART_FIFO_SIZE;
	uart->port.regshift  = 2;
	uart->port.iotype  = UPIO_MEM;
	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;

	uart->port.irq = platform_get_irq(dev, 0);
	if (uart->port.irq < 0) {
		err = -EINVAL;
		goto err_register;
	}

	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",
		.owner	= THIS_MODULE,
	},
	.probe		= timbuart_probe,
	.remove		= timbuart_remove,
};

/*--------------------------------------------------------------------------*/

static int __init timbuart_init(void)
{
	return platform_driver_register(&timbuart_platform_driver);
}

static void __exit timbuart_exit(void)
{
	platform_driver_unregister(&timbuart_platform_driver);
}

module_init(timbuart_init);
module_exit(timbuart_exit);

MODULE_DESCRIPTION("Timberdale UART driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:timb-uart");
Commit	Line	Data
34aec591 RR	1	/*
	2	* timbuart.c timberdale FPGA UART driver
	3	* Copyright (c) 2009 Intel Corporation
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License version 2 as
	7	* published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write to the Free Software
	16	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	17	*/
	18
	19	/* Supports:
	20	* Timberdale FPGA UART
	21	*/
	22
	23	#include <linux/pci.h>
	24	#include <linux/interrupt.h>
	25	#include <linux/serial_core.h>
	26	#include <linux/kernel.h>
	27	#include <linux/platform_device.h>
	28	#include <linux/ioport.h>
	29
	30	#include "timbuart.h"
	31
	32	struct timbuart_port {
	33	struct uart_port port;
	34	struct tasklet_struct tasklet;
	35	int usedma;
	36	u8 last_ier;
	37	struct platform_device *dev;
	38	};
	39
	40	static int baudrates[] = {9600, 19200, 38400, 57600, 115200, 230400, 460800,
	41	921600, 1843200, 3250000};
	42
	43	static void timbuart_mctrl_check(struct uart_port port, u8 isr, u8 ier);
	44
	45	static irqreturn_t timbuart_handleinterrupt(int irq, void *devid);
	46
	47	static void timbuart_stop_rx(struct uart_port *port)
	48	{
	49	/* spin lock held by upper layer, disable all RX interrupts */
	50	u8 ier = ioread8(port->membase + TIMBUART_IER) & ~RXFLAGS;
	51	iowrite8(ier, port->membase + TIMBUART_IER);
	52	}
	53
	54	static void timbuart_stop_tx(struct uart_port *port)
	55	{
	56	/* spinlock held by upper layer, disable TX interrupt */
	57	u8 ier = ioread8(port->membase + TIMBUART_IER) & ~TXBAE;
	58	iowrite8(ier, port->membase + TIMBUART_IER);
	59	}
	60
	61	static void timbuart_start_tx(struct uart_port *port)
	62	{
	63	struct timbuart_port *uart =
	64	container_of(port, struct timbuart_port, port);
65
66	/* do not transfer anything here -> fire off the tasklet */
67	tasklet_schedule(&uart->tasklet);
68	}
69
70	static void timbuart_flush_buffer(struct uart_port *port)
71	{
72	u8 ctl = ioread8(port->membase + TIMBUART_CTRL) \| TIMBUART_CTRL_FLSHTX;
73
74	iowrite8(ctl, port->membase + TIMBUART_CTRL);
75	iowrite8(TXBF, port->membase + TIMBUART_ISR);
76	}
77
78	static void timbuart_rx_chars(struct uart_port *port)
79	{
80	struct tty_struct *tty = port->info->port.tty;
81
82	while (ioread8(port->membase + TIMBUART_ISR) & RXDP) {
83	u8 ch = ioread8(port->membase + TIMBUART_RXFIFO);
84	port->icount.rx++;
85	tty_insert_flip_char(tty, ch, TTY_NORMAL);
86	}
87
88	spin_unlock(&port->lock);
89	tty_flip_buffer_push(port->info->port.tty);
90	spin_lock(&port->lock);
91
92	dev_dbg(port->dev, "%s - total read %d bytes\n",
93	__func__, port->icount.rx);
94	}
95
96	static void timbuart_tx_chars(struct uart_port *port)
97	{
98	struct circ_buf *xmit = &port->info->xmit;
99
100	while (!(ioread8(port->membase + TIMBUART_ISR) & TXBF) &&
101	!uart_circ_empty(xmit)) {
102	iowrite8(xmit->buf[xmit->tail],
103	port->membase + TIMBUART_TXFIFO);
104	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
105	port->icount.tx++;
106	}
107
108	dev_dbg(port->dev,
109	"%s - total written %d bytes, CTL: %x, RTS: %x, baud: %x\n",
110	__func__,
111	port->icount.tx,
112	ioread8(port->membase + TIMBUART_CTRL),
113	port->mctrl & TIOCM_RTS,
114	ioread8(port->membase + TIMBUART_BAUDRATE));
115	}
116
117	static void timbuart_handle_tx_port(struct uart_port port, u8 isr, u8 ier)
118	{
119	struct timbuart_port *uart =
120	container_of(port, struct timbuart_port, port);
121	struct circ_buf *xmit = &port->info->xmit;
122
123	if (uart_circ_empty(xmit) \|\| uart_tx_stopped(port))
124	return;
125
126	if (port->x_char)
127	return;
128
129	if (isr & TXFLAGS) {
130	timbuart_tx_chars(port);
131	/* clear all TX interrupts */
132	iowrite8(TXFLAGS, port->membase + TIMBUART_ISR);
133
134	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
135	uart_write_wakeup(port);
136	} else
137	/* Re-enable any tx interrupt */
138	*ier \|= uart->last_ier & TXFLAGS;
139
140	/* enable interrupts if there are chars in the transmit buffer,
141	* Or if we delivered some bytes and want the almost empty interrupt
142	* we wake up the upper layer later when we got the interrupt
143	* to give it some time to go out...
144	*/
145	if (!uart_circ_empty(xmit))
146	*ier \|= TXBAE;
147
148	dev_dbg(port->dev, "%s - leaving\n", __func__);
149	}
150
151	void timbuart_handle_rx_port(struct uart_port port, u8 isr, u8 ier)
152	{
153	if (isr & RXFLAGS) {
154	/* Some RX status is set */
155	if (isr & RXBF) {
156	u8 ctl = ioread8(port->membase + TIMBUART_CTRL) \|
157	TIMBUART_CTRL_FLSHRX;
158	iowrite8(ctl, port->membase + TIMBUART_CTRL);
159	port->icount.overrun++;
160	} else if (isr & (RXDP))
161	timbuart_rx_chars(port);
162
163	/* ack all RX interrupts */
164	iowrite8(RXFLAGS, port->membase + TIMBUART_ISR);
165	}
166
167	/* always have the RX interrupts enabled */
168	*ier \|= RXBAF \| RXBF \| RXTT;
169
170	dev_dbg(port->dev, "%s - leaving\n", __func__);
171	}
172
173	void timbuart_tasklet(unsigned long arg)
174	{
175	struct timbuart_port uart = (struct timbuart_port )arg;
176	u8 isr, ier = 0;
177
178	spin_lock(&uart->port.lock);
179
180	isr = ioread8(uart->port.membase + TIMBUART_ISR);
181	dev_dbg(uart->port.dev, "%s ISR: %x\n", __func__, isr);
182
183	if (!uart->usedma)
184	timbuart_handle_tx_port(&uart->port, isr, &ier);
185
186	timbuart_mctrl_check(&uart->port, isr, &ier);
187
188	if (!uart->usedma)
189	timbuart_handle_rx_port(&uart->port, isr, &ier);
190
191	iowrite8(ier, uart->port.membase + TIMBUART_IER);
192
193	spin_unlock(&uart->port.lock);
194	dev_dbg(uart->port.dev, "%s leaving\n", __func__);
195	}
196
197	static unsigned int timbuart_tx_empty(struct uart_port *port)
198	{
199	u8 isr = ioread8(port->membase + TIMBUART_ISR);
200
201	return (isr & TXBAE) ? TIOCSER_TEMT : 0;
202	}
203
204	static unsigned int timbuart_get_mctrl(struct uart_port *port)
205	{
206	u8 cts = ioread8(port->membase + TIMBUART_CTRL);
207	dev_dbg(port->dev, "%s - cts %x\n", __func__, cts);
208
209	if (cts & TIMBUART_CTRL_CTS)
210	return TIOCM_CTS \| TIOCM_DSR \| TIOCM_CAR;
211	else
212	return TIOCM_DSR \| TIOCM_CAR;
213	}
214
215	static void timbuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
216	{
217	dev_dbg(port->dev, "%s - %x\n", __func__, mctrl);
218
219	if (mctrl & TIOCM_RTS)
220	iowrite8(TIMBUART_CTRL_RTS, port->membase + TIMBUART_CTRL);
221	else
222	iowrite8(TIMBUART_CTRL_RTS, port->membase + TIMBUART_CTRL);
223	}
224
225	static void timbuart_mctrl_check(struct uart_port port, u8 isr, u8 ier)
226	{
227	unsigned int cts;
228
229	if (isr & CTS_DELTA) {
230	/* ack */
231	iowrite8(CTS_DELTA, port->membase + TIMBUART_ISR);
232	cts = timbuart_get_mctrl(port);
233	uart_handle_cts_change(port, cts & TIOCM_CTS);
234	wake_up_interruptible(&port->info->delta_msr_wait);
235	}
236
237	*ier \|= CTS_DELTA;
238	}
239
240	static void timbuart_enable_ms(struct uart_port *port)
241	{
242	/* N/A */
243	}
244
245	static void timbuart_break_ctl(struct uart_port *port, int ctl)
246	{
247	/* N/A */
248	}
249
250	static int timbuart_startup(struct uart_port *port)
251	{
252	struct timbuart_port *uart =
253	container_of(port, struct timbuart_port, port);
254
255	dev_dbg(port->dev, "%s\n", __func__);
256
257	iowrite8(TIMBUART_CTRL_FLSHRX, port->membase + TIMBUART_CTRL);
258	iowrite8(0xff, port->membase + TIMBUART_ISR);
259	/* Enable all but TX interrupts */
260	iowrite8(RXBAF \| RXBF \| RXTT \| CTS_DELTA,
261	port->membase + TIMBUART_IER);
262
263	return request_irq(port->irq, timbuart_handleinterrupt, IRQF_SHARED,
264	"timb-uart", uart);
265	}
266
267	static void timbuart_shutdown(struct uart_port *port)
268	{
269	struct timbuart_port *uart =
270	container_of(port, struct timbuart_port, port);
271	dev_dbg(port->dev, "%s\n", __func__);
272	free_irq(port->irq, uart);
273	iowrite8(0, port->membase + TIMBUART_IER);
274	}
275
276	static int get_bindex(int baud)
277	{
278	int i;
279
280	for (i = 0; i < ARRAY_SIZE(baudrates); i++)
281	if (baud == baudrates[i])
282	return i;
283
284	return -1;
285	}
286
287	static void timbuart_set_termios(struct uart_port *port,
288	struct ktermios *termios,
289	struct ktermios *old)
290	{
291	unsigned int baud;
292	short bindex;
293	unsigned long flags;
294
295	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
296	bindex = get_bindex(baud);
297	dev_dbg(port->dev, "%s - bindex %d\n", __func__, bindex);
298
299	if (bindex < 0) {
300	printk(KERN_ALERT "timbuart: Unsupported baud rate\n");
301	} else {
302	spin_lock_irqsave(&port->lock, flags);
303	iowrite8((u8)bindex, port->membase + TIMBUART_BAUDRATE);
304	uart_update_timeout(port, termios->c_cflag, baud);
305	spin_unlock_irqrestore(&port->lock, flags);
306	}
307	}
308
309	static const char timbuart_type(struct uart_port port)
310	{
311	return port->type == PORT_UNKNOWN ? "timbuart" : NULL;
312	}
313
314	/* We do not request/release mappings of the registers here,
315	* currently it's done in the proble function.
316	*/
317	static void timbuart_release_port(struct uart_port *port)
318	{
319	struct platform_device *pdev = to_platform_device(port->dev);
320	int size =
321	resource_size(platform_get_resource(pdev, IORESOURCE_MEM, 0));
322
323	if (port->flags & UPF_IOREMAP) {
324	iounmap(port->membase);
325	port->membase = NULL;
326	}
327
328	release_mem_region(port->mapbase, size);
329	}
330
331	static int timbuart_request_port(struct uart_port *port)
332	{
333	struct platform_device *pdev = to_platform_device(port->dev);
334	int size =
335	resource_size(platform_get_resource(pdev, IORESOURCE_MEM, 0));
336
337	if (!request_mem_region(port->mapbase, size, "timb-uart"))
338	return -EBUSY;
339
340	if (port->flags & UPF_IOREMAP) {
341	port->membase = ioremap(port->mapbase, size);
342	if (port->membase == NULL) {
343	release_mem_region(port->mapbase, size);
344	return -ENOMEM;
345	}
346	}
347
348	return 0;
349	}
350
351	static irqreturn_t timbuart_handleinterrupt(int irq, void *devid)
352	{
353	struct timbuart_port uart = (struct timbuart_port )devid;
354
355	if (ioread8(uart->port.membase + TIMBUART_IPR)) {
356	uart->last_ier = ioread8(uart->port.membase + TIMBUART_IER);
357
358	/* disable interrupts, the tasklet enables them again */
359	iowrite8(0, uart->port.membase + TIMBUART_IER);
360
361	/* fire off bottom half */
362	tasklet_schedule(&uart->tasklet);
363
364	return IRQ_HANDLED;
365	} else
366	return IRQ_NONE;
367	}
368
369	/*
370	* Configure/autoconfigure the port.
371	*/
372	static void timbuart_config_port(struct uart_port *port, int flags)
373	{
374	if (flags & UART_CONFIG_TYPE) {
375	port->type = PORT_TIMBUART;
376	timbuart_request_port(port);
377	}
378	}
379
380	static int timbuart_verify_port(struct uart_port *port,
381	struct serial_struct *ser)
382	{
383	/* we don't want the core code to modify any port params */
384	return -EINVAL;
385	}
386
387	static struct uart_ops timbuart_ops = {
388	.tx_empty = timbuart_tx_empty,
389	.set_mctrl = timbuart_set_mctrl,
390	.get_mctrl = timbuart_get_mctrl,
391	.stop_tx = timbuart_stop_tx,
392	.start_tx = timbuart_start_tx,
393	.flush_buffer = timbuart_flush_buffer,
394	.stop_rx = timbuart_stop_rx,
395	.enable_ms = timbuart_enable_ms,
396	.break_ctl = timbuart_break_ctl,
397	.startup = timbuart_startup,
398	.shutdown = timbuart_shutdown,
399	.set_termios = timbuart_set_termios,
400	.type = timbuart_type,
401	.release_port = timbuart_release_port,
402	.request_port = timbuart_request_port,
403	.config_port = timbuart_config_port,
404	.verify_port = timbuart_verify_port
405	};
406
407	static struct uart_driver timbuart_driver = {
408	.owner = THIS_MODULE,
409	.driver_name = "timberdale_uart",
410	.dev_name = "ttyTU",
411	.major = TIMBUART_MAJOR,
412	.minor = TIMBUART_MINOR,
413	.nr = 1
414	};
415
416	static int timbuart_probe(struct platform_device *dev)
417	{
418	int err;
419	struct timbuart_port *uart;
420	struct resource *iomem;
421
422	dev_dbg(&dev->dev, "%s\n", __func__);
423
424	uart = kzalloc(sizeof(*uart), GFP_KERNEL);
425	if (!uart) {
426	err = -EINVAL;
427	goto err_mem;
428	}
429
430	uart->usedma = 0;
431
432	uart->port.uartclk = 3250000 * 16;
433	uart->port.fifosize = TIMBUART_FIFO_SIZE;
434	uart->port.regshift = 2;
435	uart->port.iotype = UPIO_MEM;
436	uart->port.ops = &timbuart_ops;
437	uart->port.irq = 0;
438	uart->port.flags = UPF_BOOT_AUTOCONF \| UPF_IOREMAP;
439	uart->port.line = 0;
440	uart->port.dev = &dev->dev;
441
442	iomem = platform_get_resource(dev, IORESOURCE_MEM, 0);
443	if (!iomem) {
444	err = -ENOMEM;
445	goto err_register;
446	}
447	uart->port.mapbase = iomem->start;
448	uart->port.membase = NULL;
449
450	uart->port.irq = platform_get_irq(dev, 0);
451	if (uart->port.irq < 0) {
452	err = -EINVAL;
453	goto err_register;
454	}
455
456	tasklet_init(&uart->tasklet, timbuart_tasklet, (unsigned long)uart);
457
458	err = uart_register_driver(&timbuart_driver);
459	if (err)
460	goto err_register;
461
462	err = uart_add_one_port(&timbuart_driver, &uart->port);
463	if (err)
464	goto err_add_port;
465
466	platform_set_drvdata(dev, uart);
467
468	return 0;
469
470	err_add_port:
471	uart_unregister_driver(&timbuart_driver);
472	err_register:
473	kfree(uart);
474	err_mem:
475	printk(KERN_ERR "timberdale: Failed to register Timberdale UART: %d\n",
476	err);
477
478	return err;
479	}
480
481	static int timbuart_remove(struct platform_device *dev)
482	{
483	struct timbuart_port *uart = platform_get_drvdata(dev);
484
485	tasklet_kill(&uart->tasklet);
486	uart_remove_one_port(&timbuart_driver, &uart->port);
487	uart_unregister_driver(&timbuart_driver);
488	kfree(uart);
489
490	return 0;
491	}
492
493	static struct platform_driver timbuart_platform_driver = {
494	.driver = {
495	.name = "timb-uart",
496	.owner = THIS_MODULE,
497	},
498	.probe = timbuart_probe,
499	.remove = timbuart_remove,
500	};
501
502	/--------------------------------------------------------------------------/
503
504	static int __init timbuart_init(void)
505	{
506	return platform_driver_register(&timbuart_platform_driver);
507	}
508
509	static void __exit timbuart_exit(void)
510	{
511	platform_driver_unregister(&timbuart_platform_driver);
512	}
513
514	module_init(timbuart_init);
515	module_exit(timbuart_exit);
516
517	MODULE_DESCRIPTION("Timberdale UART driver");
518	MODULE_LICENSE("GPL v2");
519	MODULE_ALIAS("platform:timb-uart");
520