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path: root/drivers/tty/serial/imx.c
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Diffstat (limited to 'drivers/tty/serial/imx.c')
-rw-r--r--drivers/tty/serial/imx.c282
1 files changed, 138 insertions, 144 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 59819121fe9b..147c9e193595 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -48,8 +48,8 @@
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pinctrl/consumer.h>
+#include <linux/io.h>
-#include <asm/io.h>
#include <asm/irq.h>
#include <linux/platform_data/serial-imx.h>
@@ -73,102 +73,102 @@
#define IMX21_UTS 0xb4 /* UART Test Register on all other i.mx*/
/* UART Control Register Bit Fields.*/
-#define URXD_CHARRDY (1<<15)
-#define URXD_ERR (1<<14)
-#define URXD_OVRRUN (1<<13)
-#define URXD_FRMERR (1<<12)
-#define URXD_BRK (1<<11)
-#define URXD_PRERR (1<<10)
-#define UCR1_ADEN (1<<15) /* Auto detect interrupt */
-#define UCR1_ADBR (1<<14) /* Auto detect baud rate */
-#define UCR1_TRDYEN (1<<13) /* Transmitter ready interrupt enable */
-#define UCR1_IDEN (1<<12) /* Idle condition interrupt */
-#define UCR1_RRDYEN (1<<9) /* Recv ready interrupt enable */
-#define UCR1_RDMAEN (1<<8) /* Recv ready DMA enable */
-#define UCR1_IREN (1<<7) /* Infrared interface enable */
-#define UCR1_TXMPTYEN (1<<6) /* Transimitter empty interrupt enable */
-#define UCR1_RTSDEN (1<<5) /* RTS delta interrupt enable */
-#define UCR1_SNDBRK (1<<4) /* Send break */
-#define UCR1_TDMAEN (1<<3) /* Transmitter ready DMA enable */
-#define IMX1_UCR1_UARTCLKEN (1<<2) /* UART clock enabled, i.mx1 only */
-#define UCR1_DOZE (1<<1) /* Doze */
-#define UCR1_UARTEN (1<<0) /* UART enabled */
-#define UCR2_ESCI (1<<15) /* Escape seq interrupt enable */
-#define UCR2_IRTS (1<<14) /* Ignore RTS pin */
-#define UCR2_CTSC (1<<13) /* CTS pin control */
-#define UCR2_CTS (1<<12) /* Clear to send */
-#define UCR2_ESCEN (1<<11) /* Escape enable */
-#define UCR2_PREN (1<<8) /* Parity enable */
-#define UCR2_PROE (1<<7) /* Parity odd/even */
-#define UCR2_STPB (1<<6) /* Stop */
-#define UCR2_WS (1<<5) /* Word size */
-#define UCR2_RTSEN (1<<4) /* Request to send interrupt enable */
-#define UCR2_ATEN (1<<3) /* Aging Timer Enable */
-#define UCR2_TXEN (1<<2) /* Transmitter enabled */
-#define UCR2_RXEN (1<<1) /* Receiver enabled */
-#define UCR2_SRST (1<<0) /* SW reset */
-#define UCR3_DTREN (1<<13) /* DTR interrupt enable */
-#define UCR3_PARERREN (1<<12) /* Parity enable */
-#define UCR3_FRAERREN (1<<11) /* Frame error interrupt enable */
-#define UCR3_DSR (1<<10) /* Data set ready */
-#define UCR3_DCD (1<<9) /* Data carrier detect */
-#define UCR3_RI (1<<8) /* Ring indicator */
-#define UCR3_TIMEOUTEN (1<<7) /* Timeout interrupt enable */
-#define UCR3_RXDSEN (1<<6) /* Receive status interrupt enable */
-#define UCR3_AIRINTEN (1<<5) /* Async IR wake interrupt enable */
-#define UCR3_AWAKEN (1<<4) /* Async wake interrupt enable */
-#define IMX21_UCR3_RXDMUXSEL (1<<2) /* RXD Muxed Input Select */
-#define UCR3_INVT (1<<1) /* Inverted Infrared transmission */
-#define UCR3_BPEN (1<<0) /* Preset registers enable */
-#define UCR4_CTSTL_SHF 10 /* CTS trigger level shift */
-#define UCR4_CTSTL_MASK 0x3F /* CTS trigger is 6 bits wide */
-#define UCR4_INVR (1<<9) /* Inverted infrared reception */
-#define UCR4_ENIRI (1<<8) /* Serial infrared interrupt enable */
-#define UCR4_WKEN (1<<7) /* Wake interrupt enable */
-#define UCR4_REF16 (1<<6) /* Ref freq 16 MHz */
-#define UCR4_IRSC (1<<5) /* IR special case */
-#define UCR4_TCEN (1<<3) /* Transmit complete interrupt enable */
-#define UCR4_BKEN (1<<2) /* Break condition interrupt enable */
-#define UCR4_OREN (1<<1) /* Receiver overrun interrupt enable */
-#define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */
-#define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */
-#define UFCR_DCEDTE (1<<6) /* DCE/DTE mode select */
-#define UFCR_RFDIV (7<<7) /* Reference freq divider mask */
-#define UFCR_RFDIV_REG(x) (((x) < 7 ? 6 - (x) : 6) << 7)
-#define UFCR_TXTL_SHF 10 /* Transmitter trigger level shift */
-#define USR1_PARITYERR (1<<15) /* Parity error interrupt flag */
-#define USR1_RTSS (1<<14) /* RTS pin status */
-#define USR1_TRDY (1<<13) /* Transmitter ready interrupt/dma flag */
-#define USR1_RTSD (1<<12) /* RTS delta */
-#define USR1_ESCF (1<<11) /* Escape seq interrupt flag */
-#define USR1_FRAMERR (1<<10) /* Frame error interrupt flag */
-#define USR1_RRDY (1<<9) /* Receiver ready interrupt/dma flag */
-#define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */
-#define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */
-#define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */
-#define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */
-#define USR2_ADET (1<<15) /* Auto baud rate detect complete */
-#define USR2_TXFE (1<<14) /* Transmit buffer FIFO empty */
-#define USR2_DTRF (1<<13) /* DTR edge interrupt flag */
-#define USR2_IDLE (1<<12) /* Idle condition */
-#define USR2_IRINT (1<<8) /* Serial infrared interrupt flag */
-#define USR2_WAKE (1<<7) /* Wake */
-#define USR2_RTSF (1<<4) /* RTS edge interrupt flag */
-#define USR2_TXDC (1<<3) /* Transmitter complete */
-#define USR2_BRCD (1<<2) /* Break condition */
-#define USR2_ORE (1<<1) /* Overrun error */
-#define USR2_RDR (1<<0) /* Recv data ready */
-#define UTS_FRCPERR (1<<13) /* Force parity error */
-#define UTS_LOOP (1<<12) /* Loop tx and rx */
-#define UTS_TXEMPTY (1<<6) /* TxFIFO empty */
-#define UTS_RXEMPTY (1<<5) /* RxFIFO empty */
-#define UTS_TXFULL (1<<4) /* TxFIFO full */
-#define UTS_RXFULL (1<<3) /* RxFIFO full */
-#define UTS_SOFTRST (1<<0) /* Software reset */
+#define URXD_CHARRDY (1<<15)
+#define URXD_ERR (1<<14)
+#define URXD_OVRRUN (1<<13)
+#define URXD_FRMERR (1<<12)
+#define URXD_BRK (1<<11)
+#define URXD_PRERR (1<<10)
+#define UCR1_ADEN (1<<15) /* Auto detect interrupt */
+#define UCR1_ADBR (1<<14) /* Auto detect baud rate */
+#define UCR1_TRDYEN (1<<13) /* Transmitter ready interrupt enable */
+#define UCR1_IDEN (1<<12) /* Idle condition interrupt */
+#define UCR1_RRDYEN (1<<9) /* Recv ready interrupt enable */
+#define UCR1_RDMAEN (1<<8) /* Recv ready DMA enable */
+#define UCR1_IREN (1<<7) /* Infrared interface enable */
+#define UCR1_TXMPTYEN (1<<6) /* Transimitter empty interrupt enable */
+#define UCR1_RTSDEN (1<<5) /* RTS delta interrupt enable */
+#define UCR1_SNDBRK (1<<4) /* Send break */
+#define UCR1_TDMAEN (1<<3) /* Transmitter ready DMA enable */
+#define IMX1_UCR1_UARTCLKEN (1<<2) /* UART clock enabled, i.mx1 only */
+#define UCR1_DOZE (1<<1) /* Doze */
+#define UCR1_UARTEN (1<<0) /* UART enabled */
+#define UCR2_ESCI (1<<15) /* Escape seq interrupt enable */
+#define UCR2_IRTS (1<<14) /* Ignore RTS pin */
+#define UCR2_CTSC (1<<13) /* CTS pin control */
+#define UCR2_CTS (1<<12) /* Clear to send */
+#define UCR2_ESCEN (1<<11) /* Escape enable */
+#define UCR2_PREN (1<<8) /* Parity enable */
+#define UCR2_PROE (1<<7) /* Parity odd/even */
+#define UCR2_STPB (1<<6) /* Stop */
+#define UCR2_WS (1<<5) /* Word size */
+#define UCR2_RTSEN (1<<4) /* Request to send interrupt enable */
+#define UCR2_ATEN (1<<3) /* Aging Timer Enable */
+#define UCR2_TXEN (1<<2) /* Transmitter enabled */
+#define UCR2_RXEN (1<<1) /* Receiver enabled */
+#define UCR2_SRST (1<<0) /* SW reset */
+#define UCR3_DTREN (1<<13) /* DTR interrupt enable */
+#define UCR3_PARERREN (1<<12) /* Parity enable */
+#define UCR3_FRAERREN (1<<11) /* Frame error interrupt enable */
+#define UCR3_DSR (1<<10) /* Data set ready */
+#define UCR3_DCD (1<<9) /* Data carrier detect */
+#define UCR3_RI (1<<8) /* Ring indicator */
+#define UCR3_TIMEOUTEN (1<<7) /* Timeout interrupt enable */
+#define UCR3_RXDSEN (1<<6) /* Receive status interrupt enable */
+#define UCR3_AIRINTEN (1<<5) /* Async IR wake interrupt enable */
+#define UCR3_AWAKEN (1<<4) /* Async wake interrupt enable */
+#define IMX21_UCR3_RXDMUXSEL (1<<2) /* RXD Muxed Input Select */
+#define UCR3_INVT (1<<1) /* Inverted Infrared transmission */
+#define UCR3_BPEN (1<<0) /* Preset registers enable */
+#define UCR4_CTSTL_SHF 10 /* CTS trigger level shift */
+#define UCR4_CTSTL_MASK 0x3F /* CTS trigger is 6 bits wide */
+#define UCR4_INVR (1<<9) /* Inverted infrared reception */
+#define UCR4_ENIRI (1<<8) /* Serial infrared interrupt enable */
+#define UCR4_WKEN (1<<7) /* Wake interrupt enable */
+#define UCR4_REF16 (1<<6) /* Ref freq 16 MHz */
+#define UCR4_IRSC (1<<5) /* IR special case */
+#define UCR4_TCEN (1<<3) /* Transmit complete interrupt enable */
+#define UCR4_BKEN (1<<2) /* Break condition interrupt enable */
+#define UCR4_OREN (1<<1) /* Receiver overrun interrupt enable */
+#define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */
+#define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */
+#define UFCR_DCEDTE (1<<6) /* DCE/DTE mode select */
+#define UFCR_RFDIV (7<<7) /* Reference freq divider mask */
+#define UFCR_RFDIV_REG(x) (((x) < 7 ? 6 - (x) : 6) << 7)
+#define UFCR_TXTL_SHF 10 /* Transmitter trigger level shift */
+#define USR1_PARITYERR (1<<15) /* Parity error interrupt flag */
+#define USR1_RTSS (1<<14) /* RTS pin status */
+#define USR1_TRDY (1<<13) /* Transmitter ready interrupt/dma flag */
+#define USR1_RTSD (1<<12) /* RTS delta */
+#define USR1_ESCF (1<<11) /* Escape seq interrupt flag */
+#define USR1_FRAMERR (1<<10) /* Frame error interrupt flag */
+#define USR1_RRDY (1<<9) /* Receiver ready interrupt/dma flag */
+#define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */
+#define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */
+#define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */
+#define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */
+#define USR2_ADET (1<<15) /* Auto baud rate detect complete */
+#define USR2_TXFE (1<<14) /* Transmit buffer FIFO empty */
+#define USR2_DTRF (1<<13) /* DTR edge interrupt flag */
+#define USR2_IDLE (1<<12) /* Idle condition */
+#define USR2_IRINT (1<<8) /* Serial infrared interrupt flag */
+#define USR2_WAKE (1<<7) /* Wake */
+#define USR2_RTSF (1<<4) /* RTS edge interrupt flag */
+#define USR2_TXDC (1<<3) /* Transmitter complete */
+#define USR2_BRCD (1<<2) /* Break condition */
+#define USR2_ORE (1<<1) /* Overrun error */
+#define USR2_RDR (1<<0) /* Recv data ready */
+#define UTS_FRCPERR (1<<13) /* Force parity error */
+#define UTS_LOOP (1<<12) /* Loop tx and rx */
+#define UTS_TXEMPTY (1<<6) /* TxFIFO empty */
+#define UTS_RXEMPTY (1<<5) /* RxFIFO empty */
+#define UTS_TXFULL (1<<4) /* TxFIFO full */
+#define UTS_RXFULL (1<<3) /* RxFIFO full */
+#define UTS_SOFTRST (1<<0) /* Software reset */
/* We've been assigned a range on the "Low-density serial ports" major */
-#define SERIAL_IMX_MAJOR 207
-#define MINOR_START 16
+#define SERIAL_IMX_MAJOR 207
+#define MINOR_START 16
#define DEV_NAME "ttymxc"
/*
@@ -199,7 +199,7 @@ struct imx_port {
struct uart_port port;
struct timer_list timer;
unsigned int old_status;
- int txirq,rxirq,rtsirq;
+ int txirq, rxirq, rtsirq;
unsigned int have_rtscts:1;
unsigned int use_irda:1;
unsigned int irda_inv_rx:1;
@@ -397,7 +397,7 @@ static void imx_stop_rx(struct uart_port *port)
unsigned long temp;
temp = readl(sport->port.membase + UCR2);
- writel(temp &~ UCR2_RXEN, sport->port.membase + UCR2);
+ writel(temp & ~UCR2_RXEN, sport->port.membase + UCR2);
}
/*
@@ -490,9 +490,8 @@ static irqreturn_t imx_txint(int irq, void *dev_id)
struct circ_buf *xmit = &sport->port.state->xmit;
unsigned long flags;
- spin_lock_irqsave(&sport->port.lock,flags);
- if (sport->port.x_char)
- {
+ spin_lock_irqsave(&sport->port.lock, flags);
+ if (sport->port.x_char) {
/* Send next char */
writel(sport->port.x_char, sport->port.membase + URTX0);
goto out;
@@ -509,18 +508,18 @@ static irqreturn_t imx_txint(int irq, void *dev_id)
uart_write_wakeup(&sport->port);
out:
- spin_unlock_irqrestore(&sport->port.lock,flags);
+ spin_unlock_irqrestore(&sport->port.lock, flags);
return IRQ_HANDLED;
}
static irqreturn_t imx_rxint(int irq, void *dev_id)
{
struct imx_port *sport = dev_id;
- unsigned int rx,flg,ignored = 0;
- struct tty_struct *tty = sport->port.state->port.tty;
+ unsigned int rx, flg, ignored = 0;
+ struct tty_port *port = &sport->port.state->port;
unsigned long flags, temp;
- spin_lock_irqsave(&sport->port.lock,flags);
+ spin_lock_irqsave(&sport->port.lock, flags);
while (readl(sport->port.membase + USR2) & USR2_RDR) {
flg = TTY_NORMAL;
@@ -570,12 +569,12 @@ static irqreturn_t imx_rxint(int irq, void *dev_id)
#endif
}
- tty_insert_flip_char(tty, rx, flg);
+ tty_insert_flip_char(port, rx, flg);
}
out:
- spin_unlock_irqrestore(&sport->port.lock,flags);
- tty_flip_buffer_push(tty);
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+ tty_flip_buffer_push(port);
return IRQ_HANDLED;
}
@@ -654,7 +653,7 @@ static void imx_break_ctl(struct uart_port *port, int break_state)
temp = readl(sport->port.membase + UCR1) & ~UCR1_SNDBRK;
- if ( break_state != 0 )
+ if (break_state != 0)
temp |= UCR1_SNDBRK;
writel(temp, sport->port.membase + UCR1);
@@ -696,8 +695,8 @@ static int imx_startup(struct uart_port *port)
temp |= UCR4_IRSC;
/* set the trigger level for CTS */
- temp &= ~(UCR4_CTSTL_MASK<< UCR4_CTSTL_SHF);
- temp |= CTSTL<< UCR4_CTSTL_SHF;
+ temp &= ~(UCR4_CTSTL_MASK << UCR4_CTSTL_SHF);
+ temp |= CTSTL << UCR4_CTSTL_SHF;
writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
@@ -799,7 +798,7 @@ static int imx_startup(struct uart_port *port)
* Enable modem status interrupts
*/
imx_enable_ms(&sport->port);
- spin_unlock_irqrestore(&sport->port.lock,flags);
+ spin_unlock_irqrestore(&sport->port.lock, flags);
if (USE_IRDA(sport)) {
struct imxuart_platform_data *pdata;
@@ -909,7 +908,7 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
ucr2 = UCR2_SRST | UCR2_IRTS;
if (termios->c_cflag & CRTSCTS) {
- if( sport->have_rtscts ) {
+ if (sport->have_rtscts) {
ucr2 &= ~UCR2_IRTS;
ucr2 |= UCR2_CTSC;
} else {
@@ -969,12 +968,12 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
writel(old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN),
sport->port.membase + UCR1);
- while ( !(readl(sport->port.membase + USR2) & USR2_TXDC))
+ while (!(readl(sport->port.membase + USR2) & USR2_TXDC))
barrier();
/* then, disable everything */
old_txrxen = readl(sport->port.membase + UCR2);
- writel(old_txrxen & ~( UCR2_TXEN | UCR2_RXEN),
+ writel(old_txrxen & ~(UCR2_TXEN | UCR2_RXEN),
sport->port.membase + UCR2);
old_txrxen &= (UCR2_TXEN | UCR2_RXEN);
@@ -1212,9 +1211,15 @@ imx_console_write(struct console *co, const char *s, unsigned int count)
struct imx_port *sport = imx_ports[co->index];
struct imx_port_ucrs old_ucr;
unsigned int ucr1;
- unsigned long flags;
+ unsigned long flags = 0;
+ int locked = 1;
- spin_lock_irqsave(&sport->port.lock, flags);
+ if (sport->port.sysrq)
+ locked = 0;
+ else if (oops_in_progress)
+ locked = spin_trylock_irqsave(&sport->port.lock, flags);
+ else
+ spin_lock_irqsave(&sport->port.lock, flags);
/*
* First, save UCR1/2/3 and then disable interrupts
@@ -1241,7 +1246,8 @@ imx_console_write(struct console *co, const char *s, unsigned int count)
imx_port_ucrs_restore(&sport->port, &old_ucr);
- spin_unlock_irqrestore(&sport->port.lock, flags);
+ if (locked)
+ spin_unlock_irqrestore(&sport->port.lock, flags);
}
/*
@@ -1255,7 +1261,7 @@ imx_console_get_options(struct imx_port *sport, int *baud,
if (readl(sport->port.membase + UCR1) & UCR1_UARTEN) {
/* ok, the port was enabled */
- unsigned int ucr2, ubir,ubmr, uartclk;
+ unsigned int ucr2, ubir, ubmr, uartclk;
unsigned int baud_raw;
unsigned int ucfr_rfdiv;
@@ -1301,8 +1307,8 @@ imx_console_get_options(struct imx_port *sport, int *baud,
*baud = (baud_raw + 50) / 100 * 100;
}
- if(*baud != baud_raw)
- printk(KERN_INFO "Serial: Console IMX rounded baud rate from %d to %d\n",
+ if (*baud != baud_raw)
+ pr_info("Console IMX rounded baud rate from %d to %d\n",
baud_raw, *baud);
}
}
@@ -1324,7 +1330,7 @@ imx_console_setup(struct console *co, char *options)
if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports))
co->index = 0;
sport = imx_ports[co->index];
- if(sport == NULL)
+ if (sport == NULL)
return -ENODEV;
if (options)
@@ -1462,7 +1468,7 @@ static int serial_imx_probe(struct platform_device *pdev)
struct resource *res;
struct pinctrl *pinctrl;
- sport = kzalloc(sizeof(*sport), GFP_KERNEL);
+ sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
if (!sport)
return -ENOMEM;
@@ -1470,19 +1476,15 @@ static int serial_imx_probe(struct platform_device *pdev)
if (ret > 0)
serial_imx_probe_pdata(sport, pdev);
else if (ret < 0)
- goto free;
+ return ret;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res) {
- ret = -ENODEV;
- goto free;
- }
+ if (!res)
+ return -ENODEV;
- base = ioremap(res->start, PAGE_SIZE);
- if (!base) {
- ret = -ENOMEM;
- goto free;
- }
+ base = devm_ioremap(&pdev->dev, res->start, PAGE_SIZE);
+ if (!base)
+ return -ENOMEM;
sport->port.dev = &pdev->dev;
sport->port.mapbase = res->start;
@@ -1504,21 +1506,21 @@ static int serial_imx_probe(struct platform_device *pdev)
if (IS_ERR(pinctrl)) {
ret = PTR_ERR(pinctrl);
dev_err(&pdev->dev, "failed to get default pinctrl: %d\n", ret);
- goto unmap;
+ return ret;
}
sport->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
if (IS_ERR(sport->clk_ipg)) {
ret = PTR_ERR(sport->clk_ipg);
dev_err(&pdev->dev, "failed to get ipg clk: %d\n", ret);
- goto unmap;
+ return ret;
}
sport->clk_per = devm_clk_get(&pdev->dev, "per");
if (IS_ERR(sport->clk_per)) {
ret = PTR_ERR(sport->clk_per);
dev_err(&pdev->dev, "failed to get per clk: %d\n", ret);
- goto unmap;
+ return ret;
}
clk_prepare_enable(sport->clk_per);
@@ -1547,11 +1549,6 @@ deinit:
clkput:
clk_disable_unprepare(sport->clk_per);
clk_disable_unprepare(sport->clk_ipg);
-unmap:
- iounmap(sport->port.membase);
-free:
- kfree(sport);
-
return ret;
}
@@ -1572,9 +1569,6 @@ static int serial_imx_remove(struct platform_device *pdev)
if (pdata && pdata->exit)
pdata->exit(pdev);
- iounmap(sport->port.membase);
- kfree(sport);
-
return 0;
}
@@ -1596,7 +1590,7 @@ static int __init imx_serial_init(void)
{
int ret;
- printk(KERN_INFO "Serial: IMX driver\n");
+ pr_info("Serial: IMX driver\n");
ret = uart_register_driver(&imx_reg);
if (ret)