From: Evan Green evgreen@chromium.org
[ Upstream commit 6eefaee4f2d366a389da0eb95e524ba82bf358c4 ]
With a couple allies at Intel, and much badgering, I got confirmation from Intel that at least BXT suffers from the same SPI chip-select issue as Cannonlake (and beyond). The issue being that after going through runtime suspend/resume, toggling the chip-select line without also sending data does nothing.
Add the quirk to BXT to briefly toggle dynamic clock gating off and on, forcing the fabric to wake up enough to notice the CS register change.
Signed-off-by: Evan Green evgreen@chromium.org Cc: Shobhit Srivastava shobhit.srivastava@intel.com Cc: Andy Shevchenko andriy.shevchenko@linux.intel.com Link: https://lore.kernel.org/r/20200427163238.1.Ib1faaabe236e37ea73be9b8dcc6aa034... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-pxa2xx.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c index 2525fd9c8aa4..eafd0c2135a1 100644 --- a/drivers/spi/spi-pxa2xx.c +++ b/drivers/spi/spi-pxa2xx.c @@ -156,6 +156,7 @@ static const struct lpss_config lpss_platforms[] = { .tx_threshold_hi = 48, .cs_sel_shift = 8, .cs_sel_mask = 3 << 8, + .cs_clk_stays_gated = true, }, { /* LPSS_CNL_SSP */ .offset = 0x200,