From: Gerald Baeza <[email protected]>

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 <[email protected]>
Reviewed-by: Per Forlin <[email protected]>
Acked-by: Linus Walleij <[email protected]>
Signed-off-by: Fabio Baltieri <[email protected]>
---
 drivers/dma/ste_dma40.c                     | 15 ++++++++++-----
 include/linux/platform_data/dma-ste-dma40.h |  4 ++++
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index 5feab7db9..ca18117 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)
diff --git a/include/linux/platform_data/dma-ste-dma40.h 
b/include/linux/platform_data/dma-ste-dma40.h
index 9ff93b0..833cb95 100644
--- a/include/linux/platform_data/dma-ste-dma40.h
+++ b/include/linux/platform_data/dma-ste-dma40.h
@@ -147,6 +147,9 @@ struct stedma40_chan_cfg {
  * @memcpy_conf_log: default configuration of logical channel memcpy
  * @disabled_channels: A vector, ending with -1, that marks physical channels
  * that are for different reasons not available for the driver.
+ * @num_of_phy_chans: The number of physical channels implemented in HW.
+ * 0 means reading the number of channels from DMA HW but this is only valid
+ * for 'multiple of 4' channels, like 8.
  */
 struct stedma40_platform_data {
        u32                              dev_len;
@@ -158,6 +161,7 @@ struct stedma40_platform_data {
        struct stedma40_chan_cfg        *memcpy_conf_log;
        int                              disabled_channels[STEDMA40_MAX_PHYS];
        bool                             use_esram_lcla;
+       int                              num_of_phy_chans;
 };
 
 #ifdef CONFIG_STE_DMA40
-- 
1.7.12.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to