Patch "spi: img-spfi: fix support for speeds up to 1/4th input clock" has been added to the 4.1-stable tree

Patch "spi: img-spfi: fix support for speeds up to 1/4th input clock" has been added to the 4.1-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    spi: img-spfi: fix support for speeds up to 1/4th input clock

to the 4.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     spi-img-spfi-fix-support-for-speeds-up-to-1-4th-input-clock.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 6a806a214af42ac951e2d85e64d1bf4463482e16 Mon Sep 17 00:00:00 2001
From: Sifan Naeem <sifan.naeem@imgtec.com>
Date: Thu, 18 Jun 2015 13:50:54 +0100
Subject: spi: img-spfi: fix support for speeds up to 1/4th input clock

From: Sifan Naeem <sifan.naeem@imgtec.com>

commit 6a806a214af42ac951e2d85e64d1bf4463482e16 upstream.

Setting the Same Edge bit indicates to the spfi block to receive and
transmit data on the same edge of the spfi clock, which in turn
doubles the operating frequency of spfi.

The maximum supported frequency is limited to 1/4th of the spfi input
clock, but without this bit set the maximum would be 1/8th of the
input clock.

The current driver calculates the divisor with maximum speed at 1/4th
of the input clock, this would fail if the requested frequency is
higher than 1/8 of the input clock. Any requests for 1/8th of the
input clock would still pass.

Fixes: 8543d0e72d43 ("spi: img-spfi: Limit bit clock to 1/4th of input clock")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/spi/spi-img-spfi.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/spi/spi-img-spfi.c
+++ b/drivers/spi/spi-img-spfi.c
@@ -40,6 +40,7 @@
 #define SPFI_CONTROL_SOFT_RESET			BIT(11)
 #define SPFI_CONTROL_SEND_DMA			BIT(10)
 #define SPFI_CONTROL_GET_DMA			BIT(9)
+#define SPFI_CONTROL_SE			BIT(8)
 #define SPFI_CONTROL_TMODE_SHIFT		5
 #define SPFI_CONTROL_TMODE_MASK			0x7
 #define SPFI_CONTROL_TMODE_SINGLE		0
@@ -491,6 +492,7 @@ static void img_spfi_config(struct spi_m
 	else if (xfer->tx_nbits == SPI_NBITS_QUAD &&
 		 xfer->rx_nbits == SPI_NBITS_QUAD)
 		val |= SPFI_CONTROL_TMODE_QUAD << SPFI_CONTROL_TMODE_SHIFT;
+	val |= SPFI_CONTROL_SE;
 	spfi_writel(spfi, val, SPFI_CONTROL);
 }
 


Patches currently in stable-queue which might be from sifan.naeem@imgtec.com are

queue-4.1/spi-img-spfi-fix-support-for-speeds-up-to-1-4th-input-clock.patch