From: Alexander Usyskin Date: Wed, 24 Dec 2014 22:37:46 +0000 (+0200) Subject: mei: clean reset bit before reset X-Git-Tag: v3.16.35~3047 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=47c5594ecb1f0339ba90fa6a44d3ae2efcbb3c4a;p=thirdparty%2Fkernel%2Fstable.git mei: clean reset bit before reset commit b13a65ef190e488e2761d65bdd2e1fe8a3a125f5 upstream. H_RST bit in H_CSR register may be found lit before reset is started, for example if preceding reset flow hasn't completed. In that case asserting H_RST will be ignored, therefore we need to clean H_RST bit to start a successful reset sequence. Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman [ luis: backported to 3.16: - replace dev->dev by &dev->pdev->dev ] Signed-off-by: Luis Henriques --- diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c index 6a2d272cea43f..9d0cd32d885af 100644 --- a/drivers/misc/mei/hw-me.c +++ b/drivers/misc/mei/hw-me.c @@ -196,6 +196,18 @@ static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable) struct mei_me_hw *hw = to_me_hw(dev); u32 hcsr = mei_hcsr_read(hw); + /* H_RST may be found lit before reset is started, + * for example if preceding reset flow hasn't completed. + * In that case asserting H_RST will be ignored, therefore + * we need to clean H_RST bit to start a successful reset sequence. + */ + if ((hcsr & H_RST) == H_RST) { + dev_warn(&dev->pdev->dev, "H_RST is set = 0x%08X", hcsr); + hcsr &= ~H_RST; + mei_me_reg_write(hw, H_CSR, hcsr); + hcsr = mei_hcsr_read(hw); + } + hcsr |= H_RST | H_IG | H_IS; if (intr_enable)