| Message ID | 1427211239-4369-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c index 32a3718cc5b4..4fc4c20893e1 100644 --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -622,13 +622,13 @@ static void spi_hw_init(struct dw_spi *dws) */ if (!dws->fifo_len) { u32 fifo; - for (fifo = 2; fifo <= 256; fifo++) { + for (fifo = 1; fifo < 256; fifo++) { dw_writew(dws, DW_SPI_TXFLTR, fifo); if (fifo != dw_readw(dws, DW_SPI_TXFLTR)) break; } - dws->fifo_len = (fifo == 2) ? 0 : fifo - 1; + dws->fifo_len = (fifo == 1) ? 0 : fifo; dw_writew(dws, DW_SPI_TXFLTR, 0); } }
This is a note to let you know that I have just added a patch titled spi: dw: revisit FIFO size detection again to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt9. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From e44ea338a814f89f86dc3243a2915d6a4f786937 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Date: Wed, 25 Feb 2015 11:39:36 +0200 Subject: spi: dw: revisit FIFO size detection again commit 9d239d353c319f9ff884c287ce47feb7cdf60ddc upstream. The commit d297933cc7fc (spi: dw: Fix detecting FIFO depth) tries to fix the logic of the FIFO detection based on the description on the comments. However, there is a slight difference between numbers in TX Level and TX FIFO size. So, by specification the FIFO size would be in a range 2-256 bytes. From TX Level prospective it means we can set threshold in the range 0-(FIFO size - 1) bytes. Hence there are currently two issues: a) FIFO size 2 bytes is actually skipped since TX Level is 1 bit and could be either 0 or 1 byte; b) FIFO size is incorrectly decreased by 1 which already done by meaning of TX Level register. This patch fixes it eventually right. Fixes: d297933cc7fc (spi: dw: Fix detecting FIFO depth) Reviewed-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org> [ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/spi/spi-dw.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)