spi_mpc83xx: split mpc83xx_spi_work() into two routines

mpc83xx_spi_work() is quite large, with up to five indentation levels and
is quite difficult to read.

So, split the function in two parts:
1. mpc83xx_spi_work() now only traverse queued spi messages;
2. mpc83xx_spi_do_one_msg() only manages single messages.

There should be no functional changes.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: Kumar Gala <galak@gate.crashing.org>
Cc: David Brownell <david-b@pacbell.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 273940d3938d63cac001ccd445d907e19adce66b..e854ac0d413a3206c5051291dd0889d65536b8c5 100644 (file)
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -350,71 +350,76 @@ static int mpc83xx_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
        return mpc83xx_spi->count;
 }
 
-static void mpc83xx_spi_work(struct work_struct *work)
+static void mpc83xx_spi_do_one_msg(struct spi_message *m)
 {
-       struct mpc83xx_spi *mpc83xx_spi =
-               container_of(work, struct mpc83xx_spi, work);
-
-       spin_lock_irq(&mpc83xx_spi->lock);
-       mpc83xx_spi->busy = 1;
-       while (!list_empty(&mpc83xx_spi->queue)) {
-               struct spi_message *m;
-               struct spi_device *spi;
-               struct spi_transfer *t = NULL;
-               unsigned cs_change;
-               int status, nsecs = 50;
-
-               m = container_of(mpc83xx_spi->queue.next,
-                               struct spi_message, queue);
-               list_del_init(&m->queue);
-               spin_unlock_irq(&mpc83xx_spi->lock);
-
-               spi = m->spi;
-               cs_change = 1;
-               status = 0;
-               list_for_each_entry(t, &m->transfers, transfer_list) {
-                       if (t->bits_per_word || t->speed_hz) {
-                               /* Don't allow changes if CS is active */
-                               status = -EINVAL;
-
-                               if (cs_change)
-                                       status = mpc83xx_spi_setup_transfer(spi, t);
-                               if (status < 0)
-                                       break;
-                       }
-
-                       if (cs_change) {
-                               mpc83xx_spi_chipselect(spi, BITBANG_CS_ACTIVE);
-                               ndelay(nsecs);
-                       }
-                       cs_change = t->cs_change;
-                       if (t->len)
-                               status = mpc83xx_spi_bufs(spi, t);
-                       if (status) {
-                               status = -EMSGSIZE;
+       struct spi_device *spi = m->spi;
+       struct spi_transfer *t;
+       unsigned int cs_change;
+       const int nsecs = 50;
+       int status;
+
+       cs_change = 1;
+       status = 0;
+       list_for_each_entry(t, &m->transfers, transfer_list) {
+               if (t->bits_per_word || t->speed_hz) {
+                       /* Don't allow changes if CS is active */
+                       status = -EINVAL;
+
+                       if (cs_change)
+                               status = mpc83xx_spi_setup_transfer(spi, t);
+                       if (status < 0)
                                break;
-                       }
-                       m->actual_length += t->len;
-
-                       if (t->delay_usecs)
-                               udelay(t->delay_usecs);
+               }
 
-                       if (cs_change) {
-                               ndelay(nsecs);
-                               mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
-                               ndelay(nsecs);
-                       }
+               if (cs_change) {
+                       mpc83xx_spi_chipselect(spi, BITBANG_CS_ACTIVE);
+                       ndelay(nsecs);
+               }
+               cs_change = t->cs_change;
+               if (t->len)
+                       status = mpc83xx_spi_bufs(spi, t);
+               if (status) {
+                       status = -EMSGSIZE;
+                       break;
                }
+               m->actual_length += t->len;
 
-               m->status = status;
-               m->complete(m->context);
+               if (t->delay_usecs)
+                       udelay(t->delay_usecs);
 
-               if (status || !cs_change) {
+               if (cs_change) {
                        ndelay(nsecs);
                        mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+                       ndelay(nsecs);
                }
+       }
+
+       m->status = status;
+       m->complete(m->context);
+
+       if (status || !cs_change) {
+               ndelay(nsecs);
+               mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+       }
+
+       mpc83xx_spi_setup_transfer(spi, NULL);
+}
+
+static void mpc83xx_spi_work(struct work_struct *work)
+{
+       struct mpc83xx_spi *mpc83xx_spi = container_of(work, struct mpc83xx_spi,
+                                                      work);
+
+       spin_lock_irq(&mpc83xx_spi->lock);
+       mpc83xx_spi->busy = 1;
+       while (!list_empty(&mpc83xx_spi->queue)) {
+               struct spi_message *m = container_of(mpc83xx_spi->queue.next,
+                                                  struct spi_message, queue);
+
+               list_del_init(&m->queue);
+               spin_unlock_irq(&mpc83xx_spi->lock);
 
-               mpc83xx_spi_setup_transfer(spi, NULL);
+               mpc83xx_spi_do_one_msg(m);
 
                spin_lock_irq(&mpc83xx_spi->lock);
        }