[PATCH RFC 2/5] mmc: mmci: move block size validation under relevant code

From: Srinivas Kandagatla
Date: Tue Aug 12 2014 - 08:04:34 EST


From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>

This code moves a BUG_ON condition to relevant if block, this check is
not necessary for IPs which can set any arbitrary block size in a given
range.
This patch is necessary for SDIO which sets block sizes that are exactly
not power of 2.

Original issue detected while testing WLAN ath6kl on Qualcomm APQ8064 SOC.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
---
drivers/mmc/host/mmci.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 8641572..99fe80a 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -793,15 +793,16 @@ static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
writel(timeout, base + MMCIDATATIMER);
writel(host->size, base + MMCIDATALENGTH);

- blksz_bits = ffs(data->blksz) - 1;
- BUG_ON(1 << blksz_bits != data->blksz);

- if (variant->blksz_datactrl16)
+ if (variant->blksz_datactrl16) {
datactrl = MCI_DPSM_ENABLE | (data->blksz << 16);
- else if (variant->blksz_datactrl4)
+ } else if (variant->blksz_datactrl4) {
datactrl = MCI_DPSM_ENABLE | (data->blksz << 4);
- else
+ } else {
+ blksz_bits = ffs(data->blksz) - 1;
+ BUG_ON(1 << blksz_bits != data->blksz);
datactrl = MCI_DPSM_ENABLE | blksz_bits << 4;
+ }

if (data->flags & MMC_DATA_READ)
datactrl |= MCI_DPSM_DIRECTION;
--
1.9.1

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