staging: comedi: hwdrv_apci1500: introduce z8536_read()

The Z8536 CIO registers are indirectly read by writing the register offset to
the control register then reading the control register to get the value.

Introduce a helper function to read the Z8536 CIO registers.

The registers are read from "normal" code and in the interrupt handler,
spinlock the sequence to protect the indirect register access.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci1500.c b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci1500.c
index bfa9228..594f132 100644 (file)
--- a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci1500.c
+++ b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci1500.c
@@ -129,6 +129,20 @@ static int i_InputChannel;
 static int i_TimerCounter1Enabled, i_TimerCounter2Enabled,
           i_WatchdogCounter3Enabled;
 
+static unsigned int z8536_read(struct comedi_device *dev, unsigned int reg)
+{
+       struct apci1500_private *devpriv = dev->private;
+       unsigned long flags;
+       unsigned int val;
+
+       spin_lock_irqsave(&dev->spinlock, flags);
+       outb(reg, devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+       val = inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+       spin_unlock_irqrestore(&dev->spinlock, flags);
+
+       return val;
+}
+
 /*
  * An event can be generated for each port. The first event is related to the
  * first 8 channels (port 1) and the second to the following 6 channels (port 2)
@@ -311,14 +325,8 @@ static int apci1500_di_config(struct comedi_device *dev,
                                devpriv->iobase +
                                APCI1500_Z8536_CONTROL_REGISTER);
 
-                       /* Selects the mode specification mask    */
-                       /* register of port 1                     */
-                       outb(APCI1500_RW_PORT_A_SPECIFICATION,
-                               devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
-                       i_RegValue =
-                               inb(devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
+                       i_RegValue = z8536_read(dev,
+                                       APCI1500_RW_PORT_A_SPECIFICATION);
 
                        /* Selects the mode specification mask    */
                        /* register of port 1                     */
@@ -366,14 +374,8 @@ static int apci1500_di_config(struct comedi_device *dev,
                        outb(0x74,
                                devpriv->iobase +
                                APCI1500_Z8536_CONTROL_REGISTER);
-                       /* Selects the mode specification mask  */
-                       /* register of port B                   */
-                       outb(APCI1500_RW_PORT_B_SPECIFICATION,
-                               devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
-                       i_RegValue =
-                               inb(devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
+                       i_RegValue = z8536_read(dev,
+                                       APCI1500_RW_PORT_B_SPECIFICATION);
 
                        /* Selects the mode specification mask    */
                        /* register of port B                     */
@@ -416,14 +418,8 @@ static int apci1500_di_config(struct comedi_device *dev,
                                devpriv->iobase +
                                APCI1500_Z8536_CONTROL_REGISTER);
 
-                       /* Selects the mode specification mask    */
-                       /* register of port 2                     */
-                       outb(APCI1500_RW_PORT_B_SPECIFICATION,
-                               devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
-                       i_RegValue =
-                               inb(devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
+                       i_RegValue = z8536_read(dev,
+                                       APCI1500_RW_PORT_B_SPECIFICATION);
                        /* Selects the mode specification mask    */
                        /* register of port 2                     */
                        outb(APCI1500_RW_PORT_B_SPECIFICATION,
@@ -500,12 +496,8 @@ static int apci1500_di_write(struct comedi_device *dev,
                                                devpriv->iobase +
                                                APCI1500_Z8536_CONTROL_REGISTER);
                                        i_Event1InterruptStatus = 1;
-                                       outb(APCI1500_RW_PORT_A_SPECIFICATION,
-                                               devpriv->iobase +
-                                               APCI1500_Z8536_CONTROL_REGISTER);
-                                       i_RegValue =
-                                               inb(devpriv->iobase +
-                                               APCI1500_Z8536_CONTROL_REGISTER);
+                                       i_RegValue = z8536_read(dev,
+                                           APCI1500_RW_PORT_A_SPECIFICATION);
 
                                        /* Selects the master interrupt control register */
                                        outb(APCI1500_RW_MASTER_INTERRUPT_CONTROL, devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
@@ -1068,17 +1060,8 @@ static int apci1500_timer_config(struct comedi_device *dev,
                                        devpriv->iobase +
                                        APCI1500_Z8536_CONTROL_REGISTER);
 
-                               /* Selects the master configuration register */
-
-                               outb(APCI1500_RW_MASTER_CONFIGURATION_CONTROL,
-                                       devpriv->iobase +
-                                       APCI1500_Z8536_CONTROL_REGISTER);
-
-                               /* Reads the register */
-
-                               i_MasterConfiguration =
-                                       inb(devpriv->iobase +
-                                       APCI1500_Z8536_CONTROL_REGISTER);
+                               i_MasterConfiguration = z8536_read(dev,
+                                   APCI1500_RW_MASTER_CONFIGURATION_CONTROL);
 
                                /* Enables timer/counter 1 and triggers timer/counter 1 */
 
@@ -1228,17 +1211,8 @@ static int apci1500_timer_config(struct comedi_device *dev,
                                        devpriv->iobase +
                                        APCI1500_Z8536_CONTROL_REGISTER);
 
-                               /* Selects the master configuration register */
-
-                               outb(APCI1500_RW_MASTER_CONFIGURATION_CONTROL,
-                                       devpriv->iobase +
-                                       APCI1500_Z8536_CONTROL_REGISTER);
-
-                               /* Reads the register */
-
-                               i_MasterConfiguration =
-                                       inb(devpriv->iobase +
-                                       APCI1500_Z8536_CONTROL_REGISTER);
+                               i_MasterConfiguration = z8536_read(dev,
+                                   APCI1500_RW_MASTER_CONFIGURATION_CONTROL);
 
                                /* Enables timer/counter 2 and triggers timer/counter 2 */
 
@@ -1382,17 +1356,8 @@ static int apci1500_timer_config(struct comedi_device *dev,
                                        devpriv->iobase +
                                        APCI1500_Z8536_CONTROL_REGISTER);
 
-                               /* Selects the master configuration register */
-
-                               outb(APCI1500_RW_MASTER_CONFIGURATION_CONTROL,
-                                       devpriv->iobase +
-                                       APCI1500_Z8536_CONTROL_REGISTER);
-
-                               /* Reads the register */
-
-                               i_MasterConfiguration =
-                                       inb(devpriv->iobase +
-                                       APCI1500_Z8536_CONTROL_REGISTER);
+                               i_MasterConfiguration = z8536_read(dev,
+                                   APCI1500_RW_MASTER_CONFIGURATION_CONTROL);
 
                                /* Enables watchdog/counter 3 and triggers watchdog/counter 3 */
 
@@ -1756,21 +1721,12 @@ static int apci1500_timer_bits(struct comedi_device *dev,
                                devpriv->iobase +
                                APCI1500_Z8536_CONTROL_REGISTER);
 
-                       /* Selects the counter register (high) */
-                       outb(APCI1500_R_CPT_TMR1_VALUE_HIGH,
-                               devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
-                       data[0] =
-                               inb(devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
+                       data[0] = z8536_read(dev,
+                                            APCI1500_R_CPT_TMR1_VALUE_HIGH);
                        data[0] = data[0] << 8;
                        data[0] = data[0] & 0xff00;
-                       outb(APCI1500_R_CPT_TMR1_VALUE_LOW,
-                               devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
-                       data[0] =
-                               data[0] | inb(devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
+                       data[0] |= z8536_read(dev,
+                                             APCI1500_R_CPT_TMR1_VALUE_LOW);
                } else {
                        dev_warn(dev->class_dev,
                                "Timer/Counter1 not configured\n");
@@ -1798,21 +1754,12 @@ static int apci1500_timer_bits(struct comedi_device *dev,
                                devpriv->iobase +
                                APCI1500_Z8536_CONTROL_REGISTER);
 
-                       /* Selects the counter register (high) */
-                       outb(APCI1500_R_CPT_TMR2_VALUE_HIGH,
-                               devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
-                       data[0] =
-                               inb(devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
+                       data[0] = z8536_read(dev,
+                                            APCI1500_R_CPT_TMR2_VALUE_HIGH);
                        data[0] = data[0] << 8;
                        data[0] = data[0] & 0xff00;
-                       outb(APCI1500_R_CPT_TMR2_VALUE_LOW,
-                               devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
-                       data[0] =
-                               data[0] | inb(devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
+                       data[0] |= z8536_read(dev,
+                                             APCI1500_R_CPT_TMR2_VALUE_LOW);
                } else {
                        dev_warn(dev->class_dev,
                                "Timer/Counter2 not configured\n");
@@ -1840,21 +1787,12 @@ static int apci1500_timer_bits(struct comedi_device *dev,
                                devpriv->iobase +
                                APCI1500_Z8536_CONTROL_REGISTER);
 
-                       /* Selects the counter register (high) */
-                       outb(APCI1500_R_CPT_TMR3_VALUE_HIGH,
-                               devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
-                       data[0] =
-                               inb(devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
+                       data[0] = z8536_read(dev,
+                                            APCI1500_R_CPT_TMR3_VALUE_HIGH);
                        data[0] = data[0] << 8;
                        data[0] = data[0] & 0xff00;
-                       outb(APCI1500_R_CPT_TMR3_VALUE_LOW,
-                               devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
-                       data[0] =
-                               data[0] | inb(devpriv->iobase +
-                               APCI1500_Z8536_CONTROL_REGISTER);
+                       data[0] |= z8536_read(dev,
+                                             APCI1500_R_CPT_TMR3_VALUE_LOW);
                } else {
                        dev_warn(dev->class_dev,
                                "WatchdogCounter3 not configured\n");
@@ -1914,10 +1852,7 @@ static int apci1500_do_bits(struct comedi_device *dev,
                }
        }
 
-       /* Selects the mode specification register of port B */
-       outb(APCI1500_RW_PORT_B_SPECIFICATION,
-               devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-       i_RegValue = inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+       i_RegValue = z8536_read(dev, APCI1500_RW_PORT_B_SPECIFICATION);
        outb(APCI1500_RW_PORT_B_SPECIFICATION,
                devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
        /* Writes the new configuration (APCI1500_OR) */
@@ -1942,20 +1877,14 @@ static int apci1500_do_bits(struct comedi_device *dev,
                devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
        outb(i_Constant, devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
 
-       /* Selects the command and status register of port A */
-       outb(APCI1500_RW_PORT_A_COMMAND_AND_STATUS,
-               devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-       i_RegValue = inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+       i_RegValue = z8536_read(dev, APCI1500_RW_PORT_A_COMMAND_AND_STATUS);
        outb(APCI1500_RW_PORT_A_COMMAND_AND_STATUS,
                devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
        /* Deletes the interrupt of port A */
 
        i_RegValue = (i_RegValue & 0x0F) | 0x20;
        outb(i_RegValue, devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-       /* Selects the command and status register of port  B */
-       outb(APCI1500_RW_PORT_B_COMMAND_AND_STATUS,
-               devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-       i_RegValue = inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+       i_RegValue = z8536_read(dev, APCI1500_RW_PORT_B_COMMAND_AND_STATUS);
        outb(APCI1500_RW_PORT_B_COMMAND_AND_STATUS,
                devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
        /* Deletes the interrupt of port B */
@@ -1963,10 +1892,7 @@ static int apci1500_do_bits(struct comedi_device *dev,
        i_RegValue = (i_RegValue & 0x0F) | 0x20;
        outb(i_RegValue, devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
 
-       /* Selects the command and status register of timer 1 */
-       outb(APCI1500_RW_CPT_TMR1_CMD_STATUS,
-               devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-       i_RegValue = inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+       i_RegValue = z8536_read(dev, APCI1500_RW_CPT_TMR1_CMD_STATUS);
        outb(APCI1500_RW_CPT_TMR1_CMD_STATUS,
                devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
        /* Deletes the interrupt of timer 1 */
@@ -1974,10 +1900,7 @@ static int apci1500_do_bits(struct comedi_device *dev,
        i_RegValue = (i_RegValue & 0x0F) | 0x20;
        outb(i_RegValue, devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
 
-       /* Selects the command and status register of timer 2 */
-       outb(APCI1500_RW_CPT_TMR2_CMD_STATUS,
-               devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-       i_RegValue = inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+       i_RegValue = z8536_read(dev, APCI1500_RW_CPT_TMR2_CMD_STATUS);
        outb(APCI1500_RW_CPT_TMR2_CMD_STATUS,
                devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
        /* Deletes the interrupt of timer 2 */
@@ -1985,10 +1908,7 @@ static int apci1500_do_bits(struct comedi_device *dev,
        i_RegValue = (i_RegValue & 0x0F) | 0x20;
        outb(i_RegValue, devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
 
-       /* Selects the command and status register of timer 3 */
-       outb(APCI1500_RW_CPT_TMR3_CMD_STATUS,
-               devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-       i_RegValue = inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+       i_RegValue = z8536_read(dev, APCI1500_RW_CPT_TMR3_CMD_STATUS);
        outb(APCI1500_RW_CPT_TMR3_CMD_STATUS,
                devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
        /* Deletes the interrupt of timer 3 */
@@ -2030,11 +1950,8 @@ static irqreturn_t apci1500_interrupt(int irq, void *d)
                /* Disable all Interrupt */
                /* Selects the master interrupt control register */
                /* Disables  the main interrupt on the board */
-               /* Selects the command and status register of port A */
-               outb(APCI1500_RW_PORT_A_COMMAND_AND_STATUS,
-                       devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-               i_RegValue =
-                       inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+               i_RegValue = z8536_read(dev,
+                                       APCI1500_RW_PORT_A_COMMAND_AND_STATUS);
                if ((i_RegValue & 0x60) == 0x60) {
                        /* Selects the command and status register of port A */
                        outb(APCI1500_RW_PORT_A_COMMAND_AND_STATUS,
@@ -2047,20 +1964,11 @@ static irqreturn_t apci1500_interrupt(int irq, void *d)
                                APCI1500_Z8536_CONTROL_REGISTER);
                        i_InterruptMask = i_InterruptMask | 1;
                        if (i_Logic == APCI1500_OR_PRIORITY) {
-                               outb(APCI1500_RW_PORT_A_SPECIFICATION,
-                                       devpriv->iobase +
-                                       APCI1500_Z8536_CONTROL_REGISTER);
-                               i_RegValue =
-                                       inb(devpriv->iobase +
-                                       APCI1500_Z8536_CONTROL_REGISTER);
+                               i_RegValue = z8536_read(dev,
+                                       APCI1500_RW_PORT_A_SPECIFICATION);
 
-                               /* Selects the interrupt vector register of port A */
-                               outb(APCI1500_RW_PORT_A_INTERRUPT_CONTROL,
-                                       devpriv->iobase +
-                                       APCI1500_Z8536_CONTROL_REGISTER);
-                               i_RegValue =
-                                       inb(devpriv->iobase +
-                                       APCI1500_Z8536_CONTROL_REGISTER);
+                               i_RegValue = z8536_read(dev,
+                                       APCI1500_RW_PORT_A_INTERRUPT_CONTROL);
 
                                i_InputChannel = 1 + (i_RegValue >> 1);
 
@@ -2069,11 +1977,8 @@ static irqreturn_t apci1500_interrupt(int irq, void *d)
                        }
                }
 
-               /* Selects the command and status register of port B */
-               outb(APCI1500_RW_PORT_B_COMMAND_AND_STATUS,
-                       devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-               i_RegValue =
-                       inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+               i_RegValue = z8536_read(dev,
+                                       APCI1500_RW_PORT_B_COMMAND_AND_STATUS);
                if ((i_RegValue & 0x60) == 0x60) {
                        /* Selects the command and status register of port B */
                        outb(APCI1500_RW_PORT_B_COMMAND_AND_STATUS,
@@ -2111,11 +2016,7 @@ static irqreturn_t apci1500_interrupt(int irq, void *d)
                        }
                }
 
-               /* Selects the command and status register of timer 1 */
-               outb(APCI1500_RW_CPT_TMR1_CMD_STATUS,
-                       devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-               i_RegValue =
-                       inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+               i_RegValue = z8536_read(dev, APCI1500_RW_CPT_TMR1_CMD_STATUS);
                if ((i_RegValue & 0x60) == 0x60) {
                        /* Selects the command and status register of timer 1 */
                        outb(APCI1500_RW_CPT_TMR1_CMD_STATUS,
@@ -2128,11 +2029,8 @@ static irqreturn_t apci1500_interrupt(int irq, void *d)
                                APCI1500_Z8536_CONTROL_REGISTER);
                        i_InterruptMask = i_InterruptMask | 4;
                }
-               /* Selects the command and status register of timer 2 */
-               outb(APCI1500_RW_CPT_TMR2_CMD_STATUS,
-                       devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-               i_RegValue =
-                       inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+
+               i_RegValue = z8536_read(dev, APCI1500_RW_CPT_TMR2_CMD_STATUS);
                if ((i_RegValue & 0x60) == 0x60) {
                        /* Selects the command and status register of timer 2 */
                        outb(APCI1500_RW_CPT_TMR2_CMD_STATUS,
@@ -2146,11 +2044,7 @@ static irqreturn_t apci1500_interrupt(int irq, void *d)
                        i_InterruptMask = i_InterruptMask | 8;
                }
 
-               /* Selects the command and status register of timer 3 */
-               outb(APCI1500_RW_CPT_TMR3_CMD_STATUS,
-                       devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
-               i_RegValue =
-                       inb(devpriv->iobase + APCI1500_Z8536_CONTROL_REGISTER);
+               i_RegValue = z8536_read(dev, APCI1500_RW_CPT_TMR3_CMD_STATUS);
                if ((i_RegValue & 0x60) == 0x60) {
                        /* Selects the command and status register of timer 3 */
                        outb(APCI1500_RW_CPT_TMR3_CMD_STATUS,