dmaengine: ste_dma40: physical channels number correction

DMAC_ICFG[0:2]=SCHNB only allows to count 'multiple of 4' physical
channels so it was ok with platforms having 8 channels but cannot be
used for next versions (with 10 or 14 channels).  This patch allows to
provide the number of physical channels for a DMA device via
platform_data, or still rely on SCHNB if platform_data announces 0
channel.

Signed-off-by: Gerald Baeza <gerald.baeza@stericsson.com>
Reviewed-by: Per Forlin <per.forlin@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Fabio Baltieri <fabio.baltieri@linaro.org>

1 files changed, 10 insertions, 5 deletions

diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index 5feab7db9449..ca18117def0a 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -3004,14 +3004,21 @@ static struct d40_base * __init d40_hw_detect_init(struct platform_device *pdev)
          * ? has revision 1
          * DB8500v1 has revision 2
          * DB8500v2 has revision 3
+         * AP9540v1 has revision 4
+         * DB8540v1 has revision 4
          */
         rev = AMBA_REV_BITS(pid);
 
+        plat_data = pdev->dev.platform_data;
+
         /* The number of physical channels on this HW */
-        num_phy_chans = 4 * (readl(virtbase + D40_DREG_ICFG) & 0x7) + 4;
+        if (plat_data->num_of_phy_chans)
+                num_phy_chans = plat_data->num_of_phy_chans;
+        else
+                num_phy_chans = 4 * (readl(virtbase + D40_DREG_ICFG) & 0x7) + 4;
 
-        dev_info(&pdev->dev, "hardware revision: %d @ 0x%x\n",
-                 rev, res->start);
+        dev_info(&pdev->dev, "hardware revision: %d @ 0x%x with %d physical channels\n",
+                 rev, res->start, num_phy_chans);
 
         if (rev < 2) {
                 d40_err(&pdev->dev, "hardware revision: %d is not supported",
@@ -3019,8 +3026,6 @@ static struct d40_base * __init d40_hw_detect_init(struct platform_device *pdev)
                 goto failure;
         }
 
-        plat_data = pdev->dev.platform_data;
-
         /* Count the number of logical channels in use */
         for (i = 0; i < plat_data->dev_len; i++)
                 if (plat_data->dev_rx[i] != 0)