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From: Tom <tom.spi.devel-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
Subject: Moorestown SPI
Date: Fri, 27 May 2011 20:22:07 +0530	[thread overview]
Message-ID: <BANLkTikaHBL_+_vCc=ow2E9QzWK-58Pq0Q@mail.gmail.com> (raw)

The MRST dw_spi in Transmit & receive mode running on kernel 2.6.35,
stepping A3, is unable to receive data properly.
The slave is sending the data as expected, but the spi controller is not
reading it properly.

If i insert the messages or the delay equivalent as shown below it works.
Any clue ?

static int u8_writer(struct dw_spi *dws)
{
if (!(dw_readw(dws, sr) & SR_TF_NOT_FULL)
|| (dws->tx == dws->tx_end))
return 0;

dw_writew(dws, dr, *(u8 *)(dws->tx));
// printk("dw write %x ",*(u8 *)(dws->tx));
 udelay(50);
++dws->tx;

wait_till_not_busy(dws);
return 1;
}

static int u8_reader(struct dw_spi *dws)
{//printk("dw spi %s ",__func__);
while ((dw_readw(dws, sr) & SR_RF_NOT_EMPT)
&& (dws->rx < dws->rx_end)) {
*(u8 *)(dws->rx) = dw_readw(dws, dr);
// printk("dw read %x ",*(u8 *)(dws->rx));
udelay(50);
++dws->rx;
}

wait_till_not_busy(dws);
return dws->rx == dws->rx_end;
}
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             reply	other threads:[~2011-05-27 14:52 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-27 14:52 Tom [this message]
     [not found] ` <BANLkTikaHBL_+_vCc=ow2E9QzWK-58Pq0Q-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2011-06-09  6:16   ` Moorestown SPI Tom

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