{tty: serial, nand: onenand}: samsung: rename to fix build warning

Any arm config which has 'CONFIG_MTD_ONENAND_SAMSUNG=m' and
'CONFIG_SERIAL_SAMSUNG=m' gives a build warning:

warning: same module names found:
  drivers/tty/serial/samsung.ko
  drivers/mtd/nand/onenand/samsung.ko

Rename both drivers/tty/serial/samsung.c to
drivers/tty/serial/samsung_tty.c and drivers/mtd/nand/onenand/samsung.c
drivers/mtd/nand/onenand/samsung_mtd.c to fix the warning.

Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Acked-by: Richard Weinberger <richard@nod.at>
Link: https://lore.kernel.org/r/20191117202435.28127-1-sudipm.mukherjee@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2595 insertions, 0 deletions

diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
new file mode 100644
index 000000000000..83fd51607741
--- /dev/null
+++ b/drivers/tty/serial/samsung_tty.c
@@ -0,0 +1,2595 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver core for Samsung SoC onboard UARTs.
+ *
+ * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
+ *	http://armlinux.simtec.co.uk/
+*/
+
+/* Hote on 2410 error handling
+ *
+ * The s3c2410 manual has a love/hate affair with the contents of the
+ * UERSTAT register in the UART blocks, and keeps marking some of the
+ * error bits as reserved. Having checked with the s3c2410x01,
+ * it copes with BREAKs properly, so I am happy to ignore the RESERVED
+ * feature from the latter versions of the manual.
+ *
+ * If it becomes aparrent that latter versions of the 2410 remove these
+ * bits, then action will have to be taken to differentiate the versions
+ * and change the policy on BREAK
+ *
+ * BJD, 04-Nov-2004
+*/
+
+#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/init.h>
+#include <linux/sysrq.h>
+#include <linux/console.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/serial_s3c.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/cpufreq.h>
+#include <linux/of.h>
+
+#include <asm/irq.h>
+
+#include "samsung.h"
+
+#if	defined(CONFIG_SERIAL_SAMSUNG_DEBUG) &&	\
+	!defined(MODULE)
+
+extern void printascii(const char *);
+
+__printf(1, 2)
+static void dbg(const char *fmt, ...)
+{
+	va_list va;
+	char buff[256];
+
+	va_start(va, fmt);
+	vscnprintf(buff, sizeof(buff), fmt, va);
+	va_end(va);
+
+	printascii(buff);
+}
+
+#else
+#define dbg(fmt, ...) do { if (0) no_printk(fmt, ##__VA_ARGS__); } while (0)
+#endif
+
+/* UART name and device definitions */
+
+#define S3C24XX_SERIAL_NAME	"ttySAC"
+#define S3C24XX_SERIAL_MAJOR	204
+#define S3C24XX_SERIAL_MINOR	64
+
+#define S3C24XX_TX_PIO			1
+#define S3C24XX_TX_DMA			2
+#define S3C24XX_RX_PIO			1
+#define S3C24XX_RX_DMA			2
+/* macros to change one thing to another */
+
+#define tx_enabled(port) ((port)->unused[0])
+#define rx_enabled(port) ((port)->unused[1])
+
+/* flag to ignore all characters coming in */
+#define RXSTAT_DUMMY_READ (0x10000000)
+
+static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)
+{
+	return container_of(port, struct s3c24xx_uart_port, port);
+}
+
+/* translate a port to the device name */
+
+static inline const char *s3c24xx_serial_portname(struct uart_port *port)
+{
+	return to_platform_device(port->dev)->name;
+}
+
+static int s3c24xx_serial_txempty_nofifo(struct uart_port *port)
+{
+	return rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE;
+}
+
+/*
+ * s3c64xx and later SoC's include the interrupt mask and status registers in
+ * the controller itself, unlike the s3c24xx SoC's which have these registers
+ * in the interrupt controller. Check if the port type is s3c64xx or higher.
+ */
+static int s3c24xx_serial_has_interrupt_mask(struct uart_port *port)
+{
+	return to_ourport(port)->info->type == PORT_S3C6400;
+}
+
+static void s3c24xx_serial_rx_enable(struct uart_port *port)
+{
+	unsigned long flags;
+	unsigned int ucon, ufcon;
+	int count = 10000;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	while (--count && !s3c24xx_serial_txempty_nofifo(port))
+		udelay(100);
+
+	ufcon = rd_regl(port, S3C2410_UFCON);
+	ufcon |= S3C2410_UFCON_RESETRX;
+	wr_regl(port, S3C2410_UFCON, ufcon);
+
+	ucon = rd_regl(port, S3C2410_UCON);
+	ucon |= S3C2410_UCON_RXIRQMODE;
+	wr_regl(port, S3C2410_UCON, ucon);
+
+	rx_enabled(port) = 1;
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void s3c24xx_serial_rx_disable(struct uart_port *port)
+{
+	unsigned long flags;
+	unsigned int ucon;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	ucon = rd_regl(port, S3C2410_UCON);
+	ucon &= ~S3C2410_UCON_RXIRQMODE;
+	wr_regl(port, S3C2410_UCON, ucon);
+
+	rx_enabled(port) = 0;
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void s3c24xx_serial_stop_tx(struct uart_port *port)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+	struct s3c24xx_uart_dma *dma = ourport->dma;
+	struct circ_buf *xmit = &port->state->xmit;
+	struct dma_tx_state state;
+	int count;
+
+	if (!tx_enabled(port))
+		return;
+
+	if (s3c24xx_serial_has_interrupt_mask(port))
+		s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
+	else
+		disable_irq_nosync(ourport->tx_irq);
+
+	if (dma && dma->tx_chan && ourport->tx_in_progress == S3C24XX_TX_DMA) {
+		dmaengine_pause(dma->tx_chan);
+		dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
+		dmaengine_terminate_all(dma->tx_chan);
+		dma_sync_single_for_cpu(ourport->port.dev,
+			dma->tx_transfer_addr, dma->tx_size, DMA_TO_DEVICE);
+		async_tx_ack(dma->tx_desc);
+		count = dma->tx_bytes_requested - state.residue;
+		xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
+		port->icount.tx += count;
+	}
+
+	tx_enabled(port) = 0;
+	ourport->tx_in_progress = 0;
+
+	if (port->flags & UPF_CONS_FLOW)
+		s3c24xx_serial_rx_enable(port);
+
+	ourport->tx_mode = 0;
+}
+
+static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport);
+
+static void s3c24xx_serial_tx_dma_complete(void *args)
+{
+	struct s3c24xx_uart_port *ourport = args;
+	struct uart_port *port = &ourport->port;
+	struct circ_buf *xmit = &port->state->xmit;
+	struct s3c24xx_uart_dma *dma = ourport->dma;
+	struct dma_tx_state state;
+	unsigned long flags;
+	int count;
+
+
+	dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
+	count = dma->tx_bytes_requested - state.residue;
+	async_tx_ack(dma->tx_desc);
+
+	dma_sync_single_for_cpu(ourport->port.dev, dma->tx_transfer_addr,
+				dma->tx_size, DMA_TO_DEVICE);
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
+	port->icount.tx += count;
+	ourport->tx_in_progress = 0;
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+
+	s3c24xx_serial_start_next_tx(ourport);
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void enable_tx_dma(struct s3c24xx_uart_port *ourport)
+{
+	struct uart_port *port = &ourport->port;
+	u32 ucon;
+
+	/* Mask Tx interrupt */
+	if (s3c24xx_serial_has_interrupt_mask(port))
+		s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
+	else
+		disable_irq_nosync(ourport->tx_irq);
+
+	/* Enable tx dma mode */
+	ucon = rd_regl(port, S3C2410_UCON);
+	ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK);
+	ucon |= (dma_get_cache_alignment() >= 16) ?
+		S3C64XX_UCON_TXBURST_16 : S3C64XX_UCON_TXBURST_1;
+	ucon |= S3C64XX_UCON_TXMODE_DMA;
+	wr_regl(port,  S3C2410_UCON, ucon);
+
+	ourport->tx_mode = S3C24XX_TX_DMA;
+}
+
+static void enable_tx_pio(struct s3c24xx_uart_port *ourport)
+{
+	struct uart_port *port = &ourport->port;
+	u32 ucon, ufcon;
+
+	/* Set ufcon txtrig */
+	ourport->tx_in_progress = S3C24XX_TX_PIO;
+	ufcon = rd_regl(port, S3C2410_UFCON);
+	wr_regl(port,  S3C2410_UFCON, ufcon);
+
+	/* Enable tx pio mode */
+	ucon = rd_regl(port, S3C2410_UCON);
+	ucon &= ~(S3C64XX_UCON_TXMODE_MASK);
+	ucon |= S3C64XX_UCON_TXMODE_CPU;
+	wr_regl(port,  S3C2410_UCON, ucon);
+
+	/* Unmask Tx interrupt */
+	if (s3c24xx_serial_has_interrupt_mask(port))
+		s3c24xx_clear_bit(port, S3C64XX_UINTM_TXD,
+				  S3C64XX_UINTM);
+	else
+		enable_irq(ourport->tx_irq);
+
+	ourport->tx_mode = S3C24XX_TX_PIO;
+}
+
+static void s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port *ourport)
+{
+	if (ourport->tx_mode != S3C24XX_TX_PIO)
+		enable_tx_pio(ourport);
+}
+
+static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport,
+				      unsigned int count)
+{
+	struct uart_port *port = &ourport->port;
+	struct circ_buf *xmit = &port->state->xmit;
+	struct s3c24xx_uart_dma *dma = ourport->dma;
+
+
+	if (ourport->tx_mode != S3C24XX_TX_DMA)
+		enable_tx_dma(ourport);
+
+	dma->tx_size = count & ~(dma_get_cache_alignment() - 1);
+	dma->tx_transfer_addr = dma->tx_addr + xmit->tail;
+
+	dma_sync_single_for_device(ourport->port.dev, dma->tx_transfer_addr,
+				dma->tx_size, DMA_TO_DEVICE);
+
+	dma->tx_desc = dmaengine_prep_slave_single(dma->tx_chan,
+				dma->tx_transfer_addr, dma->tx_size,
+				DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
+	if (!dma->tx_desc) {
+		dev_err(ourport->port.dev, "Unable to get desc for Tx\n");
+		return -EIO;
+	}
+
+	dma->tx_desc->callback = s3c24xx_serial_tx_dma_complete;
+	dma->tx_desc->callback_param = ourport;
+	dma->tx_bytes_requested = dma->tx_size;
+
+	ourport->tx_in_progress = S3C24XX_TX_DMA;
+	dma->tx_cookie = dmaengine_submit(dma->tx_desc);
+	dma_async_issue_pending(dma->tx_chan);
+	return 0;
+}
+
+static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)
+{
+	struct uart_port *port = &ourport->port;
+	struct circ_buf *xmit = &port->state->xmit;
+	unsigned long count;
+
+	/* Get data size up to the end of buffer */
+	count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
+
+	if (!count) {
+		s3c24xx_serial_stop_tx(port);
+		return;
+	}
+
+	if (!ourport->dma || !ourport->dma->tx_chan ||
+	    count < ourport->min_dma_size ||
+	    xmit->tail & (dma_get_cache_alignment() - 1))
+		s3c24xx_serial_start_tx_pio(ourport);
+	else
+		s3c24xx_serial_start_tx_dma(ourport, count);
+}
+
+static void s3c24xx_serial_start_tx(struct uart_port *port)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+	struct circ_buf *xmit = &port->state->xmit;
+
+	if (!tx_enabled(port)) {
+		if (port->flags & UPF_CONS_FLOW)
+			s3c24xx_serial_rx_disable(port);
+
+		tx_enabled(port) = 1;
+		if (!ourport->dma || !ourport->dma->tx_chan)
+			s3c24xx_serial_start_tx_pio(ourport);
+	}
+
+	if (ourport->dma && ourport->dma->tx_chan) {
+		if (!uart_circ_empty(xmit) && !ourport->tx_in_progress)
+			s3c24xx_serial_start_next_tx(ourport);
+	}
+}
+
+static void s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port *ourport,
+		struct tty_port *tty, int count)
+{
+	struct s3c24xx_uart_dma *dma = ourport->dma;
+	int copied;
+
+	if (!count)
+		return;
+
+	dma_sync_single_for_cpu(ourport->port.dev, dma->rx_addr,
+				dma->rx_size, DMA_FROM_DEVICE);
+
+	ourport->port.icount.rx += count;
+	if (!tty) {
+		dev_err(ourport->port.dev, "No tty port\n");
+		return;
+	}
+	copied = tty_insert_flip_string(tty,
+			((unsigned char *)(ourport->dma->rx_buf)), count);
+	if (copied != count) {
+		WARN_ON(1);
+		dev_err(ourport->port.dev, "RxData copy to tty layer failed\n");
+	}
+}
+
+static void s3c24xx_serial_stop_rx(struct uart_port *port)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+	struct s3c24xx_uart_dma *dma = ourport->dma;
+	struct tty_port *t = &port->state->port;
+	struct dma_tx_state state;
+	enum dma_status dma_status;
+	unsigned int received;
+
+	if (rx_enabled(port)) {
+		dbg("s3c24xx_serial_stop_rx: port=%p\n", port);
+		if (s3c24xx_serial_has_interrupt_mask(port))
+			s3c24xx_set_bit(port, S3C64XX_UINTM_RXD,
+					S3C64XX_UINTM);
+		else
+			disable_irq_nosync(ourport->rx_irq);
+		rx_enabled(port) = 0;
+	}
+	if (dma && dma->rx_chan) {
+		dmaengine_pause(dma->tx_chan);
+		dma_status = dmaengine_tx_status(dma->rx_chan,
+				dma->rx_cookie, &state);
+		if (dma_status == DMA_IN_PROGRESS ||
+			dma_status == DMA_PAUSED) {
+			received = dma->rx_bytes_requested - state.residue;
+			dmaengine_terminate_all(dma->rx_chan);
+			s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
+		}
+	}
+}
+
+static inline struct s3c24xx_uart_info
+	*s3c24xx_port_to_info(struct uart_port *port)
+{
+	return to_ourport(port)->info;
+}
+
+static inline struct s3c2410_uartcfg
+	*s3c24xx_port_to_cfg(struct uart_port *port)
+{
+	struct s3c24xx_uart_port *ourport;
+
+	if (port->dev == NULL)
+		return NULL;
+
+	ourport = container_of(port, struct s3c24xx_uart_port, port);
+	return ourport->cfg;
+}
+
+static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport,
+				     unsigned long ufstat)
+{
+	struct s3c24xx_uart_info *info = ourport->info;
+
+	if (ufstat & info->rx_fifofull)
+		return ourport->port.fifosize;
+
+	return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;
+}
+
+static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport);
+static void s3c24xx_serial_rx_dma_complete(void *args)
+{
+	struct s3c24xx_uart_port *ourport = args;
+	struct uart_port *port = &ourport->port;
+
+	struct s3c24xx_uart_dma *dma = ourport->dma;
+	struct tty_port *t = &port->state->port;
+	struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
+
+	struct dma_tx_state state;
+	unsigned long flags;
+	int received;
+
+	dmaengine_tx_status(dma->rx_chan,  dma->rx_cookie, &state);
+	received  = dma->rx_bytes_requested - state.residue;
+	async_tx_ack(dma->rx_desc);
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	if (received)
+		s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
+
+	if (tty) {
+		tty_flip_buffer_push(t);
+		tty_kref_put(tty);
+	}
+
+	s3c64xx_start_rx_dma(ourport);
+
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport)
+{
+	struct s3c24xx_uart_dma *dma = ourport->dma;
+
+	dma_sync_single_for_device(ourport->port.dev, dma->rx_addr,
+				dma->rx_size, DMA_FROM_DEVICE);
+
+	dma->rx_desc = dmaengine_prep_slave_single(dma->rx_chan,
+				dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM,
+				DMA_PREP_INTERRUPT);
+	if (!dma->rx_desc) {
+		dev_err(ourport->port.dev, "Unable to get desc for Rx\n");
+		return;
+	}
+
+	dma->rx_desc->callback = s3c24xx_serial_rx_dma_complete;
+	dma->rx_desc->callback_param = ourport;
+	dma->rx_bytes_requested = dma->rx_size;
+
+	dma->rx_cookie = dmaengine_submit(dma->rx_desc);
+	dma_async_issue_pending(dma->rx_chan);
+}
+
+/* ? - where has parity gone?? */
+#define S3C2410_UERSTAT_PARITY (0x1000)
+
+static void enable_rx_dma(struct s3c24xx_uart_port *ourport)
+{
+	struct uart_port *port = &ourport->port;
+	unsigned int ucon;
+
+	/* set Rx mode to DMA mode */
+	ucon = rd_regl(port, S3C2410_UCON);
+	ucon &= ~(S3C64XX_UCON_RXBURST_MASK |
+			S3C64XX_UCON_TIMEOUT_MASK |
+			S3C64XX_UCON_EMPTYINT_EN |
+			S3C64XX_UCON_DMASUS_EN |
+			S3C64XX_UCON_TIMEOUT_EN |
+			S3C64XX_UCON_RXMODE_MASK);
+	ucon |= S3C64XX_UCON_RXBURST_16 |
+			0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
+			S3C64XX_UCON_EMPTYINT_EN |
+			S3C64XX_UCON_TIMEOUT_EN |
+			S3C64XX_UCON_RXMODE_DMA;
+	wr_regl(port, S3C2410_UCON, ucon);
+
+	ourport->rx_mode = S3C24XX_RX_DMA;
+}
+
+static void enable_rx_pio(struct s3c24xx_uart_port *ourport)
+{
+	struct uart_port *port = &ourport->port;
+	unsigned int ucon;
+
+	/* set Rx mode to DMA mode */
+	ucon = rd_regl(port, S3C2410_UCON);
+	ucon &= ~(S3C64XX_UCON_TIMEOUT_MASK |
+			S3C64XX_UCON_EMPTYINT_EN |
+			S3C64XX_UCON_DMASUS_EN |
+			S3C64XX_UCON_TIMEOUT_EN |
+			S3C64XX_UCON_RXMODE_MASK);
+	ucon |= 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
+			S3C64XX_UCON_TIMEOUT_EN |
+			S3C64XX_UCON_RXMODE_CPU;
+	wr_regl(port, S3C2410_UCON, ucon);
+
+	ourport->rx_mode = S3C24XX_RX_PIO;
+}
+
+static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport);
+
+static irqreturn_t s3c24xx_serial_rx_chars_dma(void *dev_id)
+{
+	unsigned int utrstat, ufstat, received;
+	struct s3c24xx_uart_port *ourport = dev_id;
+	struct uart_port *port = &ourport->port;
+	struct s3c24xx_uart_dma *dma = ourport->dma;
+	struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
+	struct tty_port *t = &port->state->port;
+	unsigned long flags;
+	struct dma_tx_state state;
+
+	utrstat = rd_regl(port, S3C2410_UTRSTAT);
+	ufstat = rd_regl(port, S3C2410_UFSTAT);
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) {
+		s3c64xx_start_rx_dma(ourport);
+		if (ourport->rx_mode == S3C24XX_RX_PIO)
+			enable_rx_dma(ourport);
+		goto finish;
+	}
+
+	if (ourport->rx_mode == S3C24XX_RX_DMA) {
+		dmaengine_pause(dma->rx_chan);
+		dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
+		dmaengine_terminate_all(dma->rx_chan);
+		received = dma->rx_bytes_requested - state.residue;
+		s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
+
+		enable_rx_pio(ourport);
+	}
+
+	s3c24xx_serial_rx_drain_fifo(ourport);
+
+	if (tty) {
+		tty_flip_buffer_push(t);
+		tty_kref_put(tty);
+	}
+
+	wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT);
+
+finish:
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	return IRQ_HANDLED;
+}
+
+static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
+{
+	struct uart_port *port = &ourport->port;
+	unsigned int ufcon, ch, flag, ufstat, uerstat;
+	unsigned int fifocnt = 0;
+	int max_count = port->fifosize;
+
+	while (max_count-- > 0) {
+		/*
+		 * Receive all characters known to be in FIFO
+		 * before reading FIFO level again
+		 */
+		if (fifocnt == 0) {
+			ufstat = rd_regl(port, S3C2410_UFSTAT);
+			fifocnt = s3c24xx_serial_rx_fifocnt(ourport, ufstat);
+			if (fifocnt == 0)
+				break;
+		}
+		fifocnt--;
+
+		uerstat = rd_regl(port, S3C2410_UERSTAT);
+		ch = rd_regb(port, S3C2410_URXH);
+
+		if (port->flags & UPF_CONS_FLOW) {
+			int txe = s3c24xx_serial_txempty_nofifo(port);
+
+			if (rx_enabled(port)) {
+				if (!txe) {
+					rx_enabled(port) = 0;
+					continue;
+				}
+			} else {
+				if (txe) {
+					ufcon = rd_regl(port, S3C2410_UFCON);
+					ufcon |= S3C2410_UFCON_RESETRX;
+					wr_regl(port, S3C2410_UFCON, ufcon);
+					rx_enabled(port) = 1;
+					return;
+				}
+				continue;
+			}
+		}
+
+		/* insert the character into the buffer */
+
+		flag = TTY_NORMAL;
+		port->icount.rx++;
+
+		if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
+			dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
+			    ch, uerstat);
+
+			/* check for break */
+			if (uerstat & S3C2410_UERSTAT_BREAK) {
+				dbg("break!\n");
+				port->icount.brk++;
+				if (uart_handle_break(port))
+					continue; /* Ignore character */
+			}
+
+			if (uerstat & S3C2410_UERSTAT_FRAME)
+				port->icount.frame++;
+			if (uerstat & S3C2410_UERSTAT_OVERRUN)
+				port->icount.overrun++;
+
+			uerstat &= port->read_status_mask;
+
+			if (uerstat & S3C2410_UERSTAT_BREAK)
+				flag = TTY_BREAK;
+			else if (uerstat & S3C2410_UERSTAT_PARITY)
+				flag = TTY_PARITY;
+			else if (uerstat & (S3C2410_UERSTAT_FRAME |
+					    S3C2410_UERSTAT_OVERRUN))
+				flag = TTY_FRAME;
+		}
+
+		if (uart_handle_sysrq_char(port, ch))
+			continue; /* Ignore character */
+
+		uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
+				 ch, flag);
+	}
+
+	tty_flip_buffer_push(&port->state->port);
+}
+
+static irqreturn_t s3c24xx_serial_rx_chars_pio(void *dev_id)
+{
+	struct s3c24xx_uart_port *ourport = dev_id;
+	struct uart_port *port = &ourport->port;
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->lock, flags);
+	s3c24xx_serial_rx_drain_fifo(ourport);
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	return IRQ_HANDLED;
+}
+
+
+static irqreturn_t s3c24xx_serial_rx_chars(int irq, void *dev_id)
+{
+	struct s3c24xx_uart_port *ourport = dev_id;
+
+	if (ourport->dma && ourport->dma->rx_chan)
+		return s3c24xx_serial_rx_chars_dma(dev_id);
+	return s3c24xx_serial_rx_chars_pio(dev_id);
+}
+
+static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
+{
+	struct s3c24xx_uart_port *ourport = id;
+	struct uart_port *port = &ourport->port;
+	struct circ_buf *xmit = &port->state->xmit;
+	unsigned long flags;
+	int count, dma_count = 0;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
+
+	if (ourport->dma && ourport->dma->tx_chan &&
+	    count >= ourport->min_dma_size) {
+		int align = dma_get_cache_alignment() -
+			(xmit->tail & (dma_get_cache_alignment() - 1));
+		if (count-align >= ourport->min_dma_size) {
+			dma_count = count-align;
+			count = align;
+		}
+	}
+
+	if (port->x_char) {
+		wr_regb(port, S3C2410_UTXH, port->x_char);
+		port->icount.tx++;
+		port->x_char = 0;
+		goto out;
+	}
+
+	/* if there isn't anything more to transmit, or the uart is now
+	 * stopped, disable the uart and exit
+	*/
+
+	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+		s3c24xx_serial_stop_tx(port);
+		goto out;
+	}
+
+	/* try and drain the buffer... */
+
+	if (count > port->fifosize) {
+		count = port->fifosize;
+		dma_count = 0;
+	}
+
+	while (!uart_circ_empty(xmit) && count > 0) {
+		if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
+			break;
+
+		wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		port->icount.tx++;
+		count--;
+	}
+
+	if (!count && dma_count) {
+		s3c24xx_serial_start_tx_dma(ourport, dma_count);
+		goto out;
+	}
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
+		spin_unlock(&port->lock);
+		uart_write_wakeup(port);
+		spin_lock(&port->lock);
+	}
+
+	if (uart_circ_empty(xmit))
+		s3c24xx_serial_stop_tx(port);
+
+out:
+	spin_unlock_irqrestore(&port->lock, flags);
+	return IRQ_HANDLED;
+}
+
+/* interrupt handler for s3c64xx and later SoC's.*/
+static irqreturn_t s3c64xx_serial_handle_irq(int irq, void *id)
+{
+	struct s3c24xx_uart_port *ourport = id;
+	struct uart_port *port = &ourport->port;
+	unsigned int pend = rd_regl(port, S3C64XX_UINTP);
+	irqreturn_t ret = IRQ_HANDLED;
+
+	if (pend & S3C64XX_UINTM_RXD_MSK) {
+		ret = s3c24xx_serial_rx_chars(irq, id);
+		wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_RXD_MSK);
+	}
+	if (pend & S3C64XX_UINTM_TXD_MSK) {
+		ret = s3c24xx_serial_tx_chars(irq, id);
+		wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_TXD_MSK);
+	}
+	return ret;
+}
+
+static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
+{
+	struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
+	unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT);
+	unsigned long ufcon = rd_regl(port, S3C2410_UFCON);
+
+	if (ufcon & S3C2410_UFCON_FIFOMODE) {
+		if ((ufstat & info->tx_fifomask) != 0 ||
+		    (ufstat & info->tx_fifofull))
+			return 0;
+
+		return 1;
+	}
+
+	return s3c24xx_serial_txempty_nofifo(port);
+}
+
+/* no modem control lines */
+static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
+{
+	unsigned int umstat = rd_regb(port, S3C2410_UMSTAT);
+
+	if (umstat & S3C2410_UMSTAT_CTS)
+		return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
+	else
+		return TIOCM_CAR | TIOCM_DSR;
+}
+
+static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	unsigned int umcon = rd_regl(port, S3C2410_UMCON);
+
+	if (mctrl & TIOCM_RTS)
+		umcon |= S3C2410_UMCOM_RTS_LOW;
+	else
+		umcon &= ~S3C2410_UMCOM_RTS_LOW;
+
+	wr_regl(port, S3C2410_UMCON, umcon);
+}
+
+static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
+{
+	unsigned long flags;
+	unsigned int ucon;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	ucon = rd_regl(port, S3C2410_UCON);
+
+	if (break_state)
+		ucon |= S3C2410_UCON_SBREAK;
+	else
+		ucon &= ~S3C2410_UCON_SBREAK;
+
+	wr_regl(port, S3C2410_UCON, ucon);
+
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
+{
+	struct s3c24xx_uart_dma	*dma = p->dma;
+	struct dma_slave_caps dma_caps;
+	const char *reason = NULL;
+	int ret;
+
+	/* Default slave configuration parameters */
+	dma->rx_conf.direction		= DMA_DEV_TO_MEM;
+	dma->rx_conf.src_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
+	dma->rx_conf.src_addr		= p->port.mapbase + S3C2410_URXH;
+	dma->rx_conf.src_maxburst	= 1;
+
+	dma->tx_conf.direction		= DMA_MEM_TO_DEV;
+	dma->tx_conf.dst_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
+	dma->tx_conf.dst_addr		= p->port.mapbase + S3C2410_UTXH;
+	dma->tx_conf.dst_maxburst	= 1;
+
+	dma->rx_chan = dma_request_chan(p->port.dev, "rx");
+
+	if (IS_ERR(dma->rx_chan)) {
+		reason = "DMA RX channel request failed";
+		ret = PTR_ERR(dma->rx_chan);
+		goto err_warn;
+	}
+
+	ret = dma_get_slave_caps(dma->rx_chan, &dma_caps);
+	if (ret < 0 ||
+	    dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
+		reason = "insufficient DMA RX engine capabilities";
+		ret = -EOPNOTSUPP;
+		goto err_release_rx;
+	}
+
+	dmaengine_slave_config(dma->rx_chan, &dma->rx_conf);
+
+	dma->tx_chan = dma_request_chan(p->port.dev, "tx");
+	if (IS_ERR(dma->tx_chan)) {
+		reason = "DMA TX channel request failed";
+		ret = PTR_ERR(dma->tx_chan);
+		goto err_release_rx;
+	}
+
+	ret = dma_get_slave_caps(dma->tx_chan, &dma_caps);
+	if (ret < 0 ||
+	    dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
+		reason = "insufficient DMA TX engine capabilities";
+		ret = -EOPNOTSUPP;
+		goto err_release_tx;
+	}
+
+	dmaengine_slave_config(dma->tx_chan, &dma->tx_conf);
+
+	/* RX buffer */
+	dma->rx_size = PAGE_SIZE;
+
+	dma->rx_buf = kmalloc(dma->rx_size, GFP_KERNEL);
+	if (!dma->rx_buf) {
+		ret = -ENOMEM;
+		goto err_release_tx;
+	}
+
+	dma->rx_addr = dma_map_single(p->port.dev, dma->rx_buf,
+				dma->rx_size, DMA_FROM_DEVICE);
+	if (dma_mapping_error(p->port.dev, dma->rx_addr)) {
+		reason = "DMA mapping error for RX buffer";
+		ret = -EIO;
+		goto err_free_rx;
+	}
+
+	/* TX buffer */
+	dma->tx_addr = dma_map_single(p->port.dev, p->port.state->xmit.buf,
+				UART_XMIT_SIZE, DMA_TO_DEVICE);
+	if (dma_mapping_error(p->port.dev, dma->tx_addr)) {
+		reason = "DMA mapping error for TX buffer";
+		ret = -EIO;
+		goto err_unmap_rx;
+	}
+
+	return 0;
+
+err_unmap_rx:
+	dma_unmap_single(p->port.dev, dma->rx_addr, dma->rx_size,
+			 DMA_FROM_DEVICE);
+err_free_rx:
+	kfree(dma->rx_buf);
+err_release_tx:
+	dma_release_channel(dma->tx_chan);
+err_release_rx:
+	dma_release_channel(dma->rx_chan);
+err_warn:
+	if (reason)
+		dev_warn(p->port.dev, "%s, DMA will not be used\n", reason);
+	return ret;
+}
+
+static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p)
+{
+	struct s3c24xx_uart_dma	*dma = p->dma;
+
+	if (dma->rx_chan) {
+		dmaengine_terminate_all(dma->rx_chan);
+		dma_unmap_single(p->port.dev, dma->rx_addr,
+				dma->rx_size, DMA_FROM_DEVICE);
+		kfree(dma->rx_buf);
+		dma_release_channel(dma->rx_chan);
+		dma->rx_chan = NULL;
+	}
+
+	if (dma->tx_chan) {
+		dmaengine_terminate_all(dma->tx_chan);
+		dma_unmap_single(p->port.dev, dma->tx_addr,
+				UART_XMIT_SIZE, DMA_TO_DEVICE);
+		dma_release_channel(dma->tx_chan);
+		dma->tx_chan = NULL;
+	}
+}
+
+static void s3c24xx_serial_shutdown(struct uart_port *port)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+
+	if (ourport->tx_claimed) {
+		if (!s3c24xx_serial_has_interrupt_mask(port))
+			free_irq(ourport->tx_irq, ourport);
+		tx_enabled(port) = 0;
+		ourport->tx_claimed = 0;
+		ourport->tx_mode = 0;
+	}
+
+	if (ourport->rx_claimed) {
+		if (!s3c24xx_serial_has_interrupt_mask(port))
+			free_irq(ourport->rx_irq, ourport);
+		ourport->rx_claimed = 0;
+		rx_enabled(port) = 0;
+	}
+
+	/* Clear pending interrupts and mask all interrupts */
+	if (s3c24xx_serial_has_interrupt_mask(port)) {
+		free_irq(port->irq, ourport);
+
+		wr_regl(port, S3C64XX_UINTP, 0xf);
+		wr_regl(port, S3C64XX_UINTM, 0xf);
+	}
+
+	if (ourport->dma)
+		s3c24xx_serial_release_dma(ourport);
+
+	ourport->tx_in_progress = 0;
+}
+
+static int s3c24xx_serial_startup(struct uart_port *port)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+	int ret;
+
+	dbg("s3c24xx_serial_startup: port=%p (%08llx,%p)\n",
+	    port, (unsigned long long)port->mapbase, port->membase);
+
+	rx_enabled(port) = 1;
+
+	ret = request_irq(ourport->rx_irq, s3c24xx_serial_rx_chars, 0,
+			  s3c24xx_serial_portname(port), ourport);
+
+	if (ret != 0) {
+		dev_err(port->dev, "cannot get irq %d\n", ourport->rx_irq);
+		return ret;
+	}
+
+	ourport->rx_claimed = 1;
+
+	dbg("requesting tx irq...\n");
+
+	tx_enabled(port) = 1;
+
+	ret = request_irq(ourport->tx_irq, s3c24xx_serial_tx_chars, 0,
+			  s3c24xx_serial_portname(port), ourport);
+
+	if (ret) {
+		dev_err(port->dev, "cannot get irq %d\n", ourport->tx_irq);
+		goto err;
+	}
+
+	ourport->tx_claimed = 1;
+
+	dbg("s3c24xx_serial_startup ok\n");
+
+	/* the port reset code should have done the correct
+	 * register setup for the port controls */
+
+	return ret;
+
+err:
+	s3c24xx_serial_shutdown(port);
+	return ret;
+}
+
+static int s3c64xx_serial_startup(struct uart_port *port)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+	unsigned long flags;
+	unsigned int ufcon;
+	int ret;
+
+	dbg("s3c64xx_serial_startup: port=%p (%08llx,%p)\n",
+	    port, (unsigned long long)port->mapbase, port->membase);
+
+	wr_regl(port, S3C64XX_UINTM, 0xf);
+	if (ourport->dma) {
+		ret = s3c24xx_serial_request_dma(ourport);
+		if (ret < 0) {
+			devm_kfree(port->dev, ourport->dma);
+			ourport->dma = NULL;
+		}
+	}
+
+	ret = request_irq(port->irq, s3c64xx_serial_handle_irq, IRQF_SHARED,
+			  s3c24xx_serial_portname(port), ourport);
+	if (ret) {
+		dev_err(port->dev, "cannot get irq %d\n", port->irq);
+		return ret;
+	}
+
+	/* For compatibility with s3c24xx Soc's */
+	rx_enabled(port) = 1;
+	ourport->rx_claimed = 1;
+	tx_enabled(port) = 0;
+	ourport->tx_claimed = 1;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	ufcon = rd_regl(port, S3C2410_UFCON);
+	ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;
+	if (!uart_console(port))
+		ufcon |= S3C2410_UFCON_RESETTX;
+	wr_regl(port, S3C2410_UFCON, ufcon);
+
+	enable_rx_pio(ourport);
+
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	/* Enable Rx Interrupt */
+	s3c24xx_clear_bit(port, S3C64XX_UINTM_RXD, S3C64XX_UINTM);
+
+	dbg("s3c64xx_serial_startup ok\n");
+	return ret;
+}
+
+/* power power management control */
+
+static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
+			      unsigned int old)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+	int timeout = 10000;
+
+	ourport->pm_level = level;
+
+	switch (level) {
+	case 3:
+		while (--timeout && !s3c24xx_serial_txempty_nofifo(port))
+			udelay(100);
+
+		if (!IS_ERR(ourport->baudclk))
+			clk_disable_unprepare(ourport->baudclk);
+
+		clk_disable_unprepare(ourport->clk);
+		break;
+
+	case 0:
+		clk_prepare_enable(ourport->clk);
+
+		if (!IS_ERR(ourport->baudclk))
+			clk_prepare_enable(ourport->baudclk);
+
+		break;
+	default:
+		dev_err(port->dev, "s3c24xx_serial: unknown pm %d\n", level);
+	}
+}
+
+/* baud rate calculation
+ *
+ * The UARTs on the S3C2410/S3C2440 can take their clocks from a number
+ * of different sources, including the peripheral clock ("pclk") and an
+ * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")
+ * with a programmable extra divisor.
+ *
+ * The following code goes through the clock sources, and calculates the
+ * baud clocks (and the resultant actual baud rates) and then tries to
+ * pick the closest one and select that.
+ *
+*/
+
+#define MAX_CLK_NAME_LENGTH 15
+
+static inline int s3c24xx_serial_getsource(struct uart_port *