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ads7846: SPI_CPHA mode bugfix

PATCH New David Brownell 1 participant 1 message May 22, 2007

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PATCH 1/1 ads7846: SPI_CPHA mode bugfix

From: Semih Hazar <[email protected]>

In commit [1] the SPI mode is set to 1, but it should be 0. As stated in the commit, ads784x samples the data on the rising edge. SPI mode 1 samples on the falling edge [2] though.

The root cause of this is a bug in the omap_uwire code, which treats CPHA=1 incorrectly; so these two bugs cancel each other out on one of the main regression test platforms for this driver.

[1] kernel.org GIT 7937e86a70235e1584486654687dc9908a11e00a
[2] http://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus

---
 drivers/input/touchscreen/ads7846.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/input/touchscreen/ads7846.c +1 -1
@@ -847,7 +847,7 @@ static int __devinit ads7846_probe(struc
 	 * may not.  So we stick to very-portable 8 bit words, both RX and TX.
 	 */
 	spi->bits_per_word = 8;
-	spi->mode = SPI_MODE_1;
+	spi->mode = SPI_MODE_0;
 	err = spi_setup(spi);
 	if (err < 0)
 		return err;