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avr32: at32ap700x: set DMA slave properties for MCI dw_dmac

PATCH In review Hein Tibosch 2 participants 2 messages Aug 30, 2012 MMC, SD and SDIO

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PATCH v2 1/1 avr32: at32ap700x: set DMA slave properties for MCI dw_dmac

The MCI makes use of the dw_dmac driver when DMA is being used. Due to recent changes the driver was broken because:
- the SMS field in the CTLL register received the wrong value 0
- a patch in dw_dmac (http://lkml.org/lkml/2012/1/18/52)
allowed for 64-bit transfers on the memory side, giving an illegal value of 3 in the SRC/DST_TR_WIDTH register.

This patch sets the SMS (Source Master Select) to 1 and limits the maximum transfer width to 32 bits.

Note: this can only be applied after my patch:
[PATCH v2 2/2] dw_dmac: max_mem_width limits value for SRC/DST_TR_WID register

---
 arch/avr32/mach-at32ap/at32ap700x.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
arch/avr32/mach-at32ap/at32ap700x.c +5 -0
index 0445c4f..7250c70 100644
@@ -1356,6 +1356,11 @@ at32_add_device_mci(unsigned int id, struct mci_platform_data *data)
 	slave->sdata.cfg_lo &= ~(DWC_CFGL_HS_DST_POL
 				| DWC_CFGL_HS_SRC_POL);
 
+	/* Setup DMA controller: let source be master */
+	slave->sdata.src_master = 1;
+	/* Limit maximum transfer width to 32-bit */
+	slave->sdata.max_mem_width = DW_MEM_WIDTH_32;
+
 	data->dma_slave = slave;
 
 	if (platform_device_add_data(pdev, data,
Signature · 1 line
1.7.8.0
Acked-by on v2 1/1
#1 lore raw
Quoted 7 lines · Hein Tibosch

The MCI makes use of the dw_dmac driver when DMA is being used. Due to recent changes the driver was broken because:
- the SMS field in the CTLL register received the wrong value 0
- a patch in dw_dmac (http://lkml.org/lkml/2012/1/18/52)
allowed for 64-bit transfers on the memory side, giving an illegal value of 3 in the SRC/DST_TR_WIDTH register.

Quoted 8 lines

This patch sets the SMS (Source Master Select) to 1 and limits the maximum transfer width to 32 bits.

Note: this can only be applied after my patch:
[PATCH v2 2/2] dw_dmac: max_mem_width limits value for SRC/DST_TR_WID register

<snipp diff>

Signature · 2 lines
mvh
Hans-Christian Egtvedt