[SERIAL] amba-pl010: allow platforms to specify modem control method

The amba-pl010 hardware does not provide RTS and DTR control lines; it
is expected that these will be implemented using GPIO.  Allow platforms
to supply a function to implement manipulation of modem control lines.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

3 files changed, 119 insertions, 93 deletions

diff --git a/arch/arm/mach-integrator/core.c b/arch/arm/mach-integrator/core.c
index 20071a2767cc..576a5e979c00 100644
--- a/arch/arm/mach-integrator/core.c
+++ b/arch/arm/mach-integrator/core.c
@@ -15,7 +15,9 @@
 #include <linux/interrupt.h>
 #include <linux/sched.h>
 #include <linux/smp.h>
+#include <linux/termios.h>
 #include <linux/amba/bus.h>
+#include <linux/amba/serial.h>
 
 #include <asm/hardware.h>
 #include <asm/irq.h>
@@ -28,6 +30,8 @@
 
 #include "common.h"
 
+static struct amba_pl010_data integrator_uart_data;
+
 static struct amba_device rtc_device = {
         .dev            = {
                 .bus_id = "mb:15",
@@ -44,6 +48,7 @@ static struct amba_device rtc_device = {
 static struct amba_device uart0_device = {
         .dev            = {
                 .bus_id = "mb:16",
+                .platform_data = &integrator_uart_data,
         },
         .res            = {
                 .start  = INTEGRATOR_UART0_BASE,
@@ -57,6 +62,7 @@ static struct amba_device uart0_device = {
 static struct amba_device uart1_device = {
         .dev            = {
                 .bus_id = "mb:17",
+                .platform_data = &integrator_uart_data,
         },
         .res            = {
                 .start  = INTEGRATOR_UART1_BASE,
@@ -115,6 +121,46 @@ static int __init integrator_init(void)
 
 arch_initcall(integrator_init);
 
+/*
+ * On the Integrator platform, the port RTS and DTR are provided by
+ * bits in the following SC_CTRLS register bits:
+ *        RTS  DTR
+ *  UART0  7    6
+ *  UART1  5    4
+ */
+#define SC_CTRLC        (IO_ADDRESS(INTEGRATOR_SC_BASE) + INTEGRATOR_SC_CTRLC_OFFSET)
+#define SC_CTRLS        (IO_ADDRESS(INTEGRATOR_SC_BASE) + INTEGRATOR_SC_CTRLS_OFFSET)
+
+static void integrator_uart_set_mctrl(struct amba_device *dev, void __iomem *base, unsigned int mctrl)
+{
+        unsigned int ctrls = 0, ctrlc = 0, rts_mask, dtr_mask;
+
+        if (dev == &uart0_device) {
+                rts_mask = 1 << 4;
+                dtr_mask = 1 << 5;
+        } else {
+                rts_mask = 1 << 6;
+                dtr_mask = 1 << 7;
+        }
+
+        if (mctrl & TIOCM_RTS)
+                ctrlc |= rts_mask;
+        else
+                ctrls |= rts_mask;
+
+        if (mctrl & TIOCM_DTR)
+                ctrlc |= dtr_mask;
+        else
+                ctrls |= dtr_mask;
+
+        __raw_writel(ctrls, SC_CTRLS);
+        __raw_writel(ctrlc, SC_CTRLC);
+}
+
+static struct amba_pl010_data integrator_uart_data = {
+        .set_mctrl = integrator_uart_set_mctrl,
+};
+
 #define CM_CTRL IO_ADDRESS(INTEGRATOR_HDR_BASE) + INTEGRATOR_HDR_CTRL_OFFSET
 
 static DEFINE_SPINLOCK(cm_lock);
diff --git a/drivers/serial/amba-pl010.c b/drivers/serial/amba-pl010.c
index 127d6cd5de7f..1631414000a2 100644
--- a/drivers/serial/amba-pl010.c
+++ b/drivers/serial/amba-pl010.c
@@ -51,8 +51,6 @@
 #include <linux/amba/serial.h>
 
 #include <asm/io.h>
-#include <asm/irq.h>
-#include <asm/hardware.h>
 
 #define UART_NR         2
 
@@ -65,26 +63,16 @@
 #define UART_RX_DATA(s)         (((s) & UART01x_FR_RXFE) == 0)
 #define UART_TX_READY(s)        (((s) & UART01x_FR_TXFF) == 0)
 
-#define UART_DUMMY_RSR_RX       /*256*/0
+#define UART_DUMMY_RSR_RX       256
 #define UART_PORT_SIZE          64
 
 /*
- * On the Integrator platform, the port RTS and DTR are provided by
- * bits in the following SC_CTRLS register bits:
- *        RTS  DTR
- *  UART0  7    6
- *  UART1  5    4
- */
-#define SC_CTRLC        (IO_ADDRESS(INTEGRATOR_SC_BASE) + INTEGRATOR_SC_CTRLC_OFFSET)
-#define SC_CTRLS        (IO_ADDRESS(INTEGRATOR_SC_BASE) + INTEGRATOR_SC_CTRLS_OFFSET)
-
-/*
  * We wrap our port structure around the generic uart_port.
  */
 struct uart_amba_port {
         struct uart_port        port;
-        unsigned int            dtr_mask;
-        unsigned int            rts_mask;
+        struct amba_device      *dev;
+        struct amba_pl010_data  *data;
         unsigned int            old_status;
 };
 
@@ -300,20 +288,9 @@ static unsigned int pl010_get_mctrl(struct uart_port *port)
 static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl)
 {
         struct uart_amba_port *uap = (struct uart_amba_port *)port;
-        unsigned int ctrls = 0, ctrlc = 0;
-
-        if (mctrl & TIOCM_RTS)
-                ctrlc |= uap->rts_mask;
-        else
-                ctrls |= uap->rts_mask;
 
-        if (mctrl & TIOCM_DTR)
-                ctrlc |= uap->dtr_mask;
-        else
-                ctrls |= uap->dtr_mask;
-
-        __raw_writel(ctrls, SC_CTRLS);
-        __raw_writel(ctrlc, SC_CTRLC);
+        if (uap->data)
+                uap->data->set_mctrl(uap->dev, uap->port.membase, mctrl);
 }
 
 static void pl010_break_ctl(struct uart_port *port, int break_state)
@@ -539,38 +516,7 @@ static struct uart_ops amba_pl010_pops = {
         .verify_port    = pl010_verify_port,
 };
 
-static struct uart_amba_port amba_ports[UART_NR] = {
-        {
-                .port   = {
-                        .membase        = (void *)IO_ADDRESS(INTEGRATOR_UART0_BASE),
-                        .mapbase        = INTEGRATOR_UART0_BASE,
-                        .iotype         = UPIO_MEM,
-                        .irq            = IRQ_UARTINT0,
-                        .uartclk        = 14745600,
-                        .fifosize       = 16,
-                        .ops            = &amba_pl010_pops,
-                        .flags          = UPF_BOOT_AUTOCONF,
-                        .line           = 0,
-                },
-                .dtr_mask       = 1 << 5,
-                .rts_mask       = 1 << 4,
-        },
-        {
-                .port   = {
-                        .membase        = (void *)IO_ADDRESS(INTEGRATOR_UART1_BASE),
-                        .mapbase        = INTEGRATOR_UART1_BASE,
-                        .iotype         = UPIO_MEM,
-                        .irq            = IRQ_UARTINT1,
-                        .uartclk        = 14745600,
-                        .fifosize       = 16,
-                        .ops            = &amba_pl010_pops,
-                        .flags          = UPF_BOOT_AUTOCONF,
-                        .line           = 1,
-                },
-                .dtr_mask       = 1 << 7,
-                .rts_mask       = 1 << 6,
-        }
-};
+static struct uart_amba_port *amba_ports[UART_NR];
 
 #ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
 
@@ -588,7 +534,7 @@ static void pl010_console_putchar(struct uart_port *port, int ch)
 static void
 pl010_console_write(struct console *co, const char *s, unsigned int count)
 {
-        struct uart_port *port = &amba_ports[co->index].port;
+        struct uart_port *port = &amba_ports[co->index]->port;
         unsigned int status, old_cr;
 
         /*
@@ -651,7 +597,7 @@ static int __init pl010_console_setup(struct console *co, char *options)
          */
         if (co->index >= UART_NR)
                 co->index = 0;
-        port = &amba_ports[co->index].port;
+        port = &amba_ports[co->index]->port;
 
         if (options)
                 uart_parse_options(options, &baud, &parity, &bits, &flow);
@@ -672,24 +618,6 @@ static struct console amba_console = {
         .data           = &amba_reg,
 };
 
-static int __init amba_console_init(void)
-{
-        /*
-         * All port initializations are done statically
-         */
-        register_console(&amba_console);
-        return 0;
-}
-console_initcall(amba_console_init);
-
-static int __init amba_late_console_init(void)
-{
-        if (!(amba_console.flags & CON_ENABLED))
-                register_console(&amba_console);
-        return 0;
-}
-late_initcall(amba_late_console_init);
-
 #define AMBA_CONSOLE    &amba_console
 #else
 #define AMBA_CONSOLE    NULL
@@ -707,30 +635,76 @@ static struct uart_driver amba_reg = {
 
 static int pl010_probe(struct amba_device *dev, void *id)
 {
-        int i;
+        struct uart_amba_port *port;
+        void __iomem *base;
+        int i, ret;
 
-        for (i = 0; i < UART_NR; i++) {
-                if (amba_ports[i].port.mapbase != dev->res.start)
-                        continue;
+        for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
+                if (amba_ports[i] == NULL)
+                        break;
 
-                amba_ports[i].port.dev = &dev->dev;
-                uart_add_one_port(&amba_reg, &amba_ports[i].port);
-                amba_set_drvdata(dev, &amba_ports[i]);
-                break;
+        if (i == ARRAY_SIZE(amba_ports)) {
+                ret = -EBUSY;
+                goto out;
         }
 
-        return 0;
+        port = kzalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
+        if (!port) {
+                ret = -ENOMEM;
+                goto out;
+        }
+
+        base = ioremap(dev->res.start, PAGE_SIZE);
+        if (!base) {
+                ret = -ENOMEM;
+                goto free;
+        }
+
+        port->port.dev = &dev->dev;
+        port->port.mapbase = dev->res.start;
+        port->port.membase = base;
+        port->port.iotype = UPIO_MEM;
+        port->port.irq = dev->irq[0];
+        port->port.uartclk = 14745600;
+        port->port.fifosize = 16;
+        port->port.ops = &amba_pl010_pops;
+        port->port.flags = UPF_BOOT_AUTOCONF;
+        port->port.line = i;
+        port->dev = dev;
+        port->data = dev->dev.platform_data;
+
+        amba_ports[i] = port;
+
+        amba_set_drvdata(dev, port);
+        ret = uart_add_one_port(&amba_reg, &port->port);
+        if (ret) {
+                amba_set_drvdata(dev, NULL);
+                amba_ports[i] = NULL;
+                iounmap(base);
+ free:
+                kfree(port);
+        }
+
+ out:
+        return ret;
 }
 
 static int pl010_remove(struct amba_device *dev)
 {
-        struct uart_amba_port *uap = amba_get_drvdata(dev);
-
-        if (uap)
-                uart_remove_one_port(&amba_reg, &uap->port);
+        struct uart_amba_port *port = amba_get_drvdata(dev);
+        int i;
 
         amba_set_drvdata(dev, NULL);
 
+        uart_remove_one_port(&amba_reg, &port->port);
+
+        for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
+                if (amba_ports[i] == port)
+                        amba_ports[i] = NULL;
+
+        iounmap(port->port.membase);
+        kfree(port);
+
         return 0;
 }
 
diff --git a/include/linux/amba/serial.h b/include/linux/amba/serial.h
index dc726ffccebd..48ee32a18ac5 100644
--- a/include/linux/amba/serial.h
+++ b/include/linux/amba/serial.h
@@ -158,4 +158,10 @@
 #define UART01x_RSR_ANY         (UART01x_RSR_OE|UART01x_RSR_BE|UART01x_RSR_PE|UART01x_RSR_FE)
 #define UART01x_FR_MODEM_ANY    (UART01x_FR_DCD|UART01x_FR_DSR|UART01x_FR_CTS)
 
+#ifndef __ASSEMBLY__
+struct amba_pl010_data {
+        void (*set_mctrl)(struct amba_device *dev, void __iomem *base, unsigned int mctrl);
+};
+#endif
+
 #endif