From 47db92f4a63499b1605b4c66f9347ba5479e7b19 Mon Sep 17 00:00:00 2001 From: Gerald Baeza Date: Fri, 21 Sep 2012 21:21:37 +0200 Subject: [PATCH] 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 Reviewed-by: Per Forlin Acked-by: Linus Walleij Acked-by: Vinod Koul Signed-off-by: Fabio Baltieri --- 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 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) diff --git a/include/linux/platform_data/dma-ste-dma40.h b/include/linux/platform_data/dma-ste-dma40.h index 9ff93b065686..833cb959f3df 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 -- 2.20.1