[PATCH] mmc: dw_mmc: move host->data_offset init earlier

From: James Hogan
Date: Tue Mar 12 2013 - 06:44:09 EST


host->data_offset is initialised at the end of the probe function
depending on the VERID register, and is used for PIO operations. Move
this initialisation earlier, before IRQs or slots are initialised, to be
sure that PIO won't occur prior to host->data_offset being initialised.

Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Seungwon Jeon <tgih.jun@xxxxxxxxxxx>
Cc: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
Cc: Chris Ball <cjb@xxxxxxxxxx>
---
Note, I didn't actually observe this problem occuring, but I think in
theory it could happen.

drivers/mmc/host/dw_mmc.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 1a42c7c..7556456 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -2289,6 +2289,18 @@ int dw_mci_probe(struct dw_mci *host)
mci_writel(host, CLKENA, 0);
mci_writel(host, CLKSRC, 0);

+ /*
+ * In 2.40a spec, Data offset is changed.
+ * Need to check the version-id and set data-offset for DATA register.
+ */
+ host->verid = SDMMC_GET_VERID(mci_readl(host, VERID));
+ dev_info(host->dev, "Version ID is %04x\n", host->verid);
+
+ if (host->verid < DW_MMC_240A)
+ host->data_offset = DATA_OFFSET;
+ else
+ host->data_offset = DATA_240A_OFFSET;
+
tasklet_init(&host->tasklet, dw_mci_tasklet_func, (unsigned long)host);
host->card_workqueue = alloc_workqueue("dw-mci-card",
WQ_MEM_RECLAIM | WQ_NON_REENTRANT, 1);
@@ -2337,18 +2349,6 @@ int dw_mci_probe(struct dw_mci *host)
goto err_workqueue;
}

- /*
- * In 2.40a spec, Data offset is changed.
- * Need to check the version-id and set data-offset for DATA register.
- */
- host->verid = SDMMC_GET_VERID(mci_readl(host, VERID));
- dev_info(host->dev, "Version ID is %04x\n", host->verid);
-
- if (host->verid < DW_MMC_240A)
- host->data_offset = DATA_OFFSET;
- else
- host->data_offset = DATA_240A_OFFSET;
-
if (host->quirks & DW_MCI_QUIRK_IDMAC_DTO)
dev_info(host->dev, "Internal DMAC interrupt fix enabled.\n");

--
1.8.1.2


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