mxc: add MX3 support for i.MX internal UART driver

This patch adds MX3 support for the i.MX internal uart driver.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

2 files changed, 81 insertions, 21 deletions

diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 9bc42763623c..0843c5400684 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -753,7 +753,7 @@ config BFIN_UART3_CTSRTS
 
 config SERIAL_IMX
         bool "IMX serial port support"
-        depends on ARM && ARCH_IMX
+        depends on ARM && (ARCH_IMX || ARCH_MXC)
         select SERIAL_CORE
         help
           If you have a machine based on a Motorola IMX CPU you
diff --git a/drivers/serial/imx.c b/drivers/serial/imx.c
index 9e2162ebf1bb..549440b098b2 100644
--- a/drivers/serial/imx.c
+++ b/drivers/serial/imx.c
@@ -62,6 +62,11 @@
 #define UBIR  0xa4 /* BRM Incremental Register */
 #define UBMR  0xa8 /* BRM Modulator Register */
 #define UBRC  0xac /* Baud Rate Count Register */
+#ifdef CONFIG_ARCH_MX3
+#define ONEMS 0xb0 /* One Millisecond register */
+#define UTS   0xb4 /* UART Test Register */
+#endif
+#ifdef CONFIG_ARCH_IMX
 #define BIPR1 0xb0 /* Incremental Preset Register 1 */
 #define BIPR2 0xb4 /* Incremental Preset Register 2 */
 #define BIPR3 0xb8 /* Incremental Preset Register 3 */
@@ -71,6 +76,7 @@
 #define BMPR3 0xc8 /* BRM Modulator Register 3 */
 #define BMPR4 0xcc /* BRM Modulator Register 4 */
 #define UTS   0xd0 /* UART Test Register */
+#endif
 
 /* UART Control Register Bit Fields.*/
 #define  URXD_CHARRDY    (1<<15)
@@ -90,7 +96,12 @@
 #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 */
+#ifdef CONFIG_ARCH_IMX
 #define  UCR1_UARTCLKEN  (1<<2)  /* UART clock enabled */
+#endif
+#ifdef CONFIG_ARCH_MX3
+#define  UCR1_UARTCLKEN  (0)     /* not present on mx2/mx3 */
+#endif
 #define  UCR1_DOZE       (1<<1)  /* Doze */
 #define  UCR1_UARTEN     (1<<0)  /* UART enabled */
 #define  UCR2_ESCI       (1<<15) /* Escape seq interrupt enable */
@@ -164,8 +175,19 @@
 #define  UTS_SOFTRST     (1<<0)  /* Software reset */
 
 /* We've been assigned a range on the "Low-density serial ports" major */
+#ifdef CONFIG_ARCH_IMX
 #define SERIAL_IMX_MAJOR        204
 #define MINOR_START             41
+#define DEV_NAME                "ttySMX"
+#define MAX_INTERNAL_IRQ        IMX_IRQS
+#endif
+
+#ifdef CONFIG_ARCH_MX3
+#define SERIAL_IMX_MAJOR        207
+#define MINOR_START             16
+#define DEV_NAME                "ttymxc"
+#define MAX_INTERNAL_IRQ        MXC_MAX_INT_LINES
+#endif
 
 /*
  * This determines how often we check the modem status signals
@@ -409,6 +431,26 @@ out:
         return IRQ_HANDLED;
 }
 
+static irqreturn_t imx_int(int irq, void *dev_id)
+{
+        struct imx_port *sport = dev_id;
+        unsigned int sts;
+
+        sts = readl(sport->port.membase + USR1);
+
+        if (sts & USR1_RRDY)
+                imx_rxint(irq, dev_id);
+
+        if (sts & USR1_TRDY &&
+                        readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN)
+                imx_txint(irq, dev_id);
+
+        if (sts & USR1_RTSS)
+                imx_rtsint(irq, dev_id);
+
+        return IRQ_HANDLED;
+}
+
 /*
  * Return TIOCSER_TEMT when transmitter is not busy.
  */
@@ -514,21 +556,34 @@ static int imx_startup(struct uart_port *port)
         writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
 
         /*
-         * Allocate the IRQ
+         * Allocate the IRQ(s) i.MX1 has three interrupts whereas later
+         * chips only have one interrupt.
          */
-        retval = request_irq(sport->rxirq, imx_rxint, 0,
-                             DRIVER_NAME, sport);
-        if (retval) goto error_out1;
-
-        retval = request_irq(sport->txirq, imx_txint, 0,
-                             DRIVER_NAME, sport);
-        if (retval) goto error_out2;
-
-        retval = request_irq(sport->rtsirq, imx_rtsint,
-                             (sport->rtsirq < IMX_IRQS) ? 0 :
+        if (sport->txirq > 0) {
+                retval = request_irq(sport->rxirq, imx_rxint, 0,
+                                DRIVER_NAME, sport);
+                if (retval)
+                        goto error_out1;
+
+                retval = request_irq(sport->txirq, imx_txint, 0,
+                                DRIVER_NAME, sport);
+                if (retval)
+                        goto error_out2;
+
+                retval = request_irq(sport->rtsirq, imx_rtsint,
+                             (sport->rtsirq < MAX_INTERNAL_IRQ) ? 0 :
                                IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
-                             DRIVER_NAME, sport);
-        if (retval) goto error_out3;
+                                DRIVER_NAME, sport);
+                if (retval)
+                        goto error_out3;
+        } else {
+                retval = request_irq(sport->port.irq, imx_int, 0,
+                                DRIVER_NAME, sport);
+                if (retval) {
+                        free_irq(sport->port.irq, sport);
+                        goto error_out1;
+                }
+        }
 
         /*
          * Finally, clear and enable interrupts
@@ -553,9 +608,11 @@ static int imx_startup(struct uart_port *port)
         return 0;
 
 error_out3:
-        free_irq(sport->txirq, sport);
+        if (sport->txirq)
+                free_irq(sport->txirq, sport);
 error_out2:
-        free_irq(sport->rxirq, sport);
+        if (sport->rxirq)
+                free_irq(sport->rxirq, sport);
 error_out1:
         return retval;
 }
@@ -573,9 +630,12 @@ static void imx_shutdown(struct uart_port *port)
         /*
          * Free the interrupts
          */
-        free_irq(sport->rtsirq, sport);
-        free_irq(sport->txirq, sport);
-        free_irq(sport->rxirq, sport);
+        if (sport->txirq > 0) {
+                free_irq(sport->rtsirq, sport);
+                free_irq(sport->txirq, sport);
+                free_irq(sport->rxirq, sport);
+        } else
+                free_irq(sport->port.irq, sport);
 
         /*
          * Disable all interrupts, port and break condition.
@@ -973,7 +1033,7 @@ imx_console_setup(struct console *co, char *options)
 
 static struct uart_driver imx_reg;
 static struct console imx_console = {
-        .name           = "ttySMX",
+        .name           = DEV_NAME,
         .write          = imx_console_write,
         .device         = uart_console_device,
         .setup          = imx_console_setup,
@@ -990,7 +1050,7 @@ static struct console imx_console = {
 static struct uart_driver imx_reg = {
         .owner          = THIS_MODULE,
         .driver_name    = DRIVER_NAME,
-        .dev_name       = "ttySMX",
+        .dev_name       = DEV_NAME,
         .major          = SERIAL_IMX_MAJOR,
         .minor          = MINOR_START,
         .nr             = ARRAY_SIZE(imx_ports),