rt2x00: Cleanup indirect register access

All code which accessed indirect registers was similar
in respect to the for-loop, the given timeout, etc.
Move it into a seperate function, which for PCI drivers
can be moved into rt2x00pci.

This allows us to cleanup the cleanup the code further
by removing the goto statementsand making the codepath
look a bit nicer.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 64 insertions, 83 deletions

diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index d1a63e0017da..b4ca8488beff 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -63,7 +63,7 @@ static inline void rt73usb_register_read(struct rt2x00_dev *rt2x00dev,
         __le32 reg;
         rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
                                       USB_VENDOR_REQUEST_IN, offset,
-                                      &reg, sizeof(u32), REGISTER_TIMEOUT);
+                                      &reg, sizeof(reg), REGISTER_TIMEOUT);
         *value = le32_to_cpu(reg);
 }
 
@@ -73,7 +73,7 @@ static inline void rt73usb_register_read_lock(struct rt2x00_dev *rt2x00dev,
         __le32 reg;
         rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_READ,
                                        USB_VENDOR_REQUEST_IN, offset,
-                                       &reg, sizeof(u32), REGISTER_TIMEOUT);
+                                       &reg, sizeof(reg), REGISTER_TIMEOUT);
         *value = le32_to_cpu(reg);
 }
 
@@ -93,7 +93,7 @@ static inline void rt73usb_register_write(struct rt2x00_dev *rt2x00dev,
         __le32 reg = cpu_to_le32(value);
         rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_WRITE,
                                       USB_VENDOR_REQUEST_OUT, offset,
-                                      &reg, sizeof(u32), REGISTER_TIMEOUT);
+                                      &reg, sizeof(reg), REGISTER_TIMEOUT);
 }
 
 static inline void rt73usb_register_write_lock(struct rt2x00_dev *rt2x00dev,
@@ -102,7 +102,7 @@ static inline void rt73usb_register_write_lock(struct rt2x00_dev *rt2x00dev,
         __le32 reg = cpu_to_le32(value);
         rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_WRITE,
                                        USB_VENDOR_REQUEST_OUT, offset,
-                                      &reg, sizeof(u32), REGISTER_TIMEOUT);
+                                       &reg, sizeof(reg), REGISTER_TIMEOUT);
 }
 
 static inline void rt73usb_register_multiwrite(struct rt2x00_dev *rt2x00dev,
@@ -115,21 +115,32 @@ static inline void rt73usb_register_multiwrite(struct rt2x00_dev *rt2x00dev,
                                       REGISTER_TIMEOUT32(length));
 }
 
-static u32 rt73usb_bbp_check(struct rt2x00_dev *rt2x00dev)
+static int rt73usb_regbusy_read(struct rt2x00_dev *rt2x00dev,
+                                const unsigned int offset,
+                                struct rt2x00_field32 field,
+                                u32 *reg)
 {
-        u32 reg;
         unsigned int i;
 
         for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
-                rt73usb_register_read_lock(rt2x00dev, PHY_CSR3, &reg);
-                if (!rt2x00_get_field32(reg, PHY_CSR3_BUSY))
-                        break;
+                rt73usb_register_read_lock(rt2x00dev, offset, reg);
+                if (!rt2x00_get_field32(*reg, field))
+                        return 1;
                 udelay(REGISTER_BUSY_DELAY);
         }
 
-        return reg;
+        ERROR(rt2x00dev, "Indirect register access failed: "
+              "offset=0x%.08x, value=0x%.08x\n", offset, *reg);
+        *reg = ~0;
+
+        return 0;
 }
 
+#define WAIT_FOR_BBP(__dev, __reg) \
+        rt73usb_regbusy_read((__dev), PHY_CSR3, PHY_CSR3_BUSY, (__reg))
+#define WAIT_FOR_RF(__dev, __reg) \
+        rt73usb_regbusy_read((__dev), PHY_CSR4, PHY_CSR4_BUSY, (__reg))
+
 static void rt73usb_bbp_write(struct rt2x00_dev *rt2x00dev,
                               const unsigned int word, const u8 value)
 {
@@ -138,30 +149,20 @@ static void rt73usb_bbp_write(struct rt2x00_dev *rt2x00dev,
         mutex_lock(&rt2x00dev->csr_mutex);
 
         /*
-         * Wait until the BBP becomes ready.
+         * Wait until the BBP becomes available, afterwards we
+         * can safely write the new data into the register.
          */
-        reg = rt73usb_bbp_check(rt2x00dev);
-        if (rt2x00_get_field32(reg, PHY_CSR3_BUSY))
-                goto exit_fail;
-
-        /*
-         * Write the data into the BBP.
-         */
-        reg = 0;
-        rt2x00_set_field32(&reg, PHY_CSR3_VALUE, value);
-        rt2x00_set_field32(&reg, PHY_CSR3_REGNUM, word);
-        rt2x00_set_field32(&reg, PHY_CSR3_BUSY, 1);
-        rt2x00_set_field32(&reg, PHY_CSR3_READ_CONTROL, 0);
-
-        rt73usb_register_write_lock(rt2x00dev, PHY_CSR3, reg);
-        mutex_unlock(&rt2x00dev->csr_mutex);
-
-        return;
+        if (WAIT_FOR_BBP(rt2x00dev, &reg)) {
+                reg = 0;
+                rt2x00_set_field32(&reg, PHY_CSR3_VALUE, value);
+                rt2x00_set_field32(&reg, PHY_CSR3_REGNUM, word);
+                rt2x00_set_field32(&reg, PHY_CSR3_BUSY, 1);
+                rt2x00_set_field32(&reg, PHY_CSR3_READ_CONTROL, 0);
+
+                rt73usb_register_write_lock(rt2x00dev, PHY_CSR3, reg);
+        }
 
-exit_fail:
         mutex_unlock(&rt2x00dev->csr_mutex);
-
-        ERROR(rt2x00dev, "PHY_CSR3 register busy. Write failed.\n");
 }
 
 static void rt73usb_bbp_read(struct rt2x00_dev *rt2x00dev,
@@ -172,79 +173,59 @@ static void rt73usb_bbp_read(struct rt2x00_dev *rt2x00dev,
         mutex_lock(&rt2x00dev->csr_mutex);
 
         /*
-         * Wait until the BBP becomes ready.
+         * Wait until the BBP becomes available, afterwards we
+         * can safely write the read request into the register.
+         * After the data has been written, we wait until hardware
+         * returns the correct value, if at any time the register
+         * doesn't become available in time, reg will be 0xffffffff
+         * which means we return 0xff to the caller.
          */
-        reg = rt73usb_bbp_check(rt2x00dev);
-        if (rt2x00_get_field32(reg, PHY_CSR3_BUSY))
-                goto exit_fail;
+        if (WAIT_FOR_BBP(rt2x00dev, &reg)) {
+                reg = 0;
+                rt2x00_set_field32(&reg, PHY_CSR3_REGNUM, word);
+                rt2x00_set_field32(&reg, PHY_CSR3_BUSY, 1);
+                rt2x00_set_field32(&reg, PHY_CSR3_READ_CONTROL, 1);
 
-        /*
-         * Write the request into the BBP.
-         */
-        reg = 0;
-        rt2x00_set_field32(&reg, PHY_CSR3_REGNUM, word);
-        rt2x00_set_field32(&reg, PHY_CSR3_BUSY, 1);
-        rt2x00_set_field32(&reg, PHY_CSR3_READ_CONTROL, 1);
+                rt73usb_register_write_lock(rt2x00dev, PHY_CSR3, reg);
 
-        rt73usb_register_write_lock(rt2x00dev, PHY_CSR3, reg);
-
-        /*
-         * Wait until the BBP becomes ready.
-         */
-        reg = rt73usb_bbp_check(rt2x00dev);
-        if (rt2x00_get_field32(reg, PHY_CSR3_BUSY))
-                goto exit_fail;
+                WAIT_FOR_BBP(rt2x00dev, &reg);
+        }
 
         *value = rt2x00_get_field32(reg, PHY_CSR3_VALUE);
-        mutex_unlock(&rt2x00dev->csr_mutex);
-
-        return;
 
-exit_fail:
         mutex_unlock(&rt2x00dev->csr_mutex);
-
-        ERROR(rt2x00dev, "PHY_CSR3 register busy. Read failed.\n");
-        *value = 0xff;
 }
 
 static void rt73usb_rf_write(struct rt2x00_dev *rt2x00dev,
                              const unsigned int word, const u32 value)
 {
         u32 reg;
-        unsigned int i;
 
         if (!word)
                 return;
 
         mutex_lock(&rt2x00dev->csr_mutex);
 
-        for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
-                rt73usb_register_read_lock(rt2x00dev, PHY_CSR4, &reg);
-                if (!rt2x00_get_field32(reg, PHY_CSR4_BUSY))
-                        goto rf_write;
-                udelay(REGISTER_BUSY_DELAY);
-        }
-
-        mutex_unlock(&rt2x00dev->csr_mutex);
-        ERROR(rt2x00dev, "PHY_CSR4 register busy. Write failed.\n");
-        return;
-
-rf_write:
-        reg = 0;
-        rt2x00_set_field32(&reg, PHY_CSR4_VALUE, value);
-
         /*
-         * RF5225 and RF2527 contain 21 bits per RF register value,
-         * all others contain 20 bits.
+         * Wait until the RF becomes available, afterwards we
+         * can safely write the new data into the register.
          */
-        rt2x00_set_field32(&reg, PHY_CSR4_NUMBER_OF_BITS,
-                           20 + (rt2x00_rf(&rt2x00dev->chip, RF5225) ||
-                                 rt2x00_rf(&rt2x00dev->chip, RF2527)));
-        rt2x00_set_field32(&reg, PHY_CSR4_IF_SELECT, 0);
-        rt2x00_set_field32(&reg, PHY_CSR4_BUSY, 1);
-
-        rt73usb_register_write_lock(rt2x00dev, PHY_CSR4, reg);
-        rt2x00_rf_write(rt2x00dev, word, value);
+        if (WAIT_FOR_RF(rt2x00dev, &reg)) {
+                reg = 0;
+                rt2x00_set_field32(&reg, PHY_CSR4_VALUE, value);
+                /*
+                 * RF5225 and RF2527 contain 21 bits per RF register value,
+                 * all others contain 20 bits.
+                 */
+                rt2x00_set_field32(&reg, PHY_CSR4_NUMBER_OF_BITS,
+                                   20 + (rt2x00_rf(&rt2x00dev->chip, RF5225) ||
+                                         rt2x00_rf(&rt2x00dev->chip, RF2527)));
+                rt2x00_set_field32(&reg, PHY_CSR4_IF_SELECT, 0);
+                rt2x00_set_field32(&reg, PHY_CSR4_BUSY, 1);
+
+                rt73usb_register_write_lock(rt2x00dev, PHY_CSR4, reg);
+                rt2x00_rf_write(rt2x00dev, word, value);
+        }
 
         mutex_unlock(&rt2x00dev->csr_mutex);
 }