staging: comedi: amplc_pci230: replace `state` member with bitfields
authorIan Abbott <abbotti@mev.co.uk>
Mon, 1 Sep 2014 11:03:53 +0000 (12:03 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 2 Sep 2014 18:21:32 +0000 (11:21 -0700)
The `state` member of `struct pci230_private` is used with the atomic
bit-op functions and has a couple of bits defined, `AI_CMD_STARTED` and
`AO_CMD_STARTED`.  Spin-locks are used to protect the clearing of these
bits and other stuff.  No special protection is used for setting these
bits.  Replace the `state` member with a couple of new, single-bit
bitfield members, `ai_cmd_started` and `ao_cmd_started` to save some
space.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/staging/comedi/drivers/amplc_pci230.c

index 29e6016..7a8291a 100644 (file)
@@ -443,10 +443,6 @@ enum {
 /* Current CPU.  XXX should this be hard_smp_processor_id()? */
 #define THISCPU                smp_processor_id()
 
-/* State flags for atomic bit operations */
-#define AI_CMD_STARTED 0
-#define AO_CMD_STARTED 1
-
 /*
  * Board descriptions for the two boards supported.
  */
@@ -495,7 +491,6 @@ struct pci230_private {
        spinlock_t ai_stop_spinlock;    /* Spin lock for stopping AI command */
        spinlock_t ao_stop_spinlock;    /* Spin lock for stopping AO command */
        unsigned long daqio;            /* PCI230's DAQ I/O space */
-       unsigned long state;            /* State flags */
        unsigned int ai_scan_count;     /* Number of AI scans remaining */
        unsigned int ai_scan_pos;       /* Current position within AI scan */
        unsigned int ao_scan_count;     /* Number of AO scans remaining.  */
@@ -511,6 +506,8 @@ struct pci230_private {
        bool intr_running:1;            /* Flag set in interrupt routine */
        bool ai_bipolar:1;              /* Flag AI range is bipolar */
        bool ao_bipolar:1;              /* Flag AO range is bipolar */
+       bool ai_cmd_started:1;          /* Flag AI command started */
+       bool ao_cmd_started:1;          /* Flag AO command started */
 };
 
 /* PCI230 clock source periods in ns */
@@ -1060,11 +1057,12 @@ static void pci230_ao_stop(struct comedi_device *dev,
        struct pci230_private *devpriv = dev->private;
        unsigned long irqflags;
        unsigned char intsrc;
-       int started;
+       bool started;
        struct comedi_cmd *cmd;
 
        spin_lock_irqsave(&devpriv->ao_stop_spinlock, irqflags);
-       started = test_and_clear_bit(AO_CMD_STARTED, &devpriv->state);
+       started = devpriv->ao_cmd_started;
+       devpriv->ao_cmd_started = false;
        spin_unlock_irqrestore(&devpriv->ao_stop_spinlock, irqflags);
        if (!started)
                return;
@@ -1263,7 +1261,7 @@ static int pci230_ao_inttrig_scan_begin(struct comedi_device *dev,
                return -EINVAL;
 
        spin_lock_irqsave(&devpriv->ao_stop_spinlock, irqflags);
-       if (test_bit(AO_CMD_STARTED, &devpriv->state)) {
+       if (devpriv->ao_cmd_started) {
                /* Perform scan. */
                if (devpriv->hwver < 2) {
                        /* Not using DAC FIFO. */
@@ -1296,7 +1294,7 @@ static void pci230_ao_start(struct comedi_device *dev,
        struct comedi_cmd *cmd = &async->cmd;
        unsigned long irqflags;
 
-       set_bit(AO_CMD_STARTED, &devpriv->state);
+       devpriv->ao_cmd_started = true;
        if (cmd->stop_src == TRIG_COUNT && devpriv->ao_scan_count == 0) {
                /* An empty acquisition! */
                async->events |= COMEDI_CB_EOA;
@@ -1852,7 +1850,7 @@ static int pci230_ai_inttrig_convert(struct comedi_device *dev,
                return -EINVAL;
 
        spin_lock_irqsave(&devpriv->ai_stop_spinlock, irqflags);
-       if (test_bit(AI_CMD_STARTED, &devpriv->state)) {
+       if (devpriv->ai_cmd_started) {
                unsigned int delayus;
 
                /*
@@ -1899,7 +1897,7 @@ static int pci230_ai_inttrig_scan_begin(struct comedi_device *dev,
                return -EINVAL;
 
        spin_lock_irqsave(&devpriv->ai_stop_spinlock, irqflags);
-       if (test_bit(AI_CMD_STARTED, &devpriv->state)) {
+       if (devpriv->ai_cmd_started) {
                /* Trigger scan by waggling CT0 gate source. */
                zgat = GAT_CONFIG(0, GAT_GND);
                outb(zgat, dev->iobase + PCI230_ZGAT_SCE);
@@ -1917,10 +1915,11 @@ static void pci230_ai_stop(struct comedi_device *dev,
        struct pci230_private *devpriv = dev->private;
        unsigned long irqflags;
        struct comedi_cmd *cmd;
-       int started;
+       bool started;
 
        spin_lock_irqsave(&devpriv->ai_stop_spinlock, irqflags);
-       started = test_and_clear_bit(AI_CMD_STARTED, &devpriv->state);
+       started = devpriv->ai_cmd_started;
+       devpriv->ai_cmd_started = false;
        spin_unlock_irqrestore(&devpriv->ai_stop_spinlock, irqflags);
        if (!started)
                return;
@@ -1970,7 +1969,7 @@ static void pci230_ai_start(struct comedi_device *dev,
        struct comedi_async *async = s->async;
        struct comedi_cmd *cmd = &async->cmd;
 
-       set_bit(AI_CMD_STARTED, &devpriv->state);
+       devpriv->ai_cmd_started = true;
        if (cmd->stop_src == TRIG_COUNT && devpriv->ai_scan_count == 0) {
                /* An empty acquisition! */
                async->events |= COMEDI_CB_EOA;