Merge tag 'pinctrl-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...

Pull two pinctrl fixes from Linus Walleij:
 - Fixed a 2-line compile error for MXS
 - A pure documentation fix for Nomadik

* tag 'pinctrl-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl/nomadik: document Alt-C glitch
  pinctrl: mxs: Use kfree to fix build error

diff --git a/drivers/pinctrl/pinctrl-mxs.c b/drivers/pinctrl/pinctrl-mxs.c
index afb50ee64598454dcc11ca3729c499b62387c285..4ba4636b6a4ac6b67d30b366299b2452bb983b76 100644 (file)
--- a/drivers/pinctrl/pinctrl-mxs.c
+++ b/drivers/pinctrl/pinctrl-mxs.c
@@ -137,7 +137,7 @@ static int mxs_dt_node_to_map(struct pinctrl_dev *pctldev,
 
 free_group:
        if (!purecfg)
-               free(group);
+               kfree(group);
 free:
        kfree(new_map);
        return ret;

diff --git a/drivers/pinctrl/pinctrl-nomadik.c b/drivers/pinctrl/pinctrl-nomadik.c
index e8937e7e4999897db278508b081b2fd780499982..3e7e47d6b38526178b0985bf0e7162f8fab16d70 100644 (file)
--- a/drivers/pinctrl/pinctrl-nomadik.c
+++ b/drivers/pinctrl/pinctrl-nomadik.c
@@ -1438,7 +1438,27 @@ static int nmk_pmx_enable(struct pinctrl_dev *pctldev, unsigned function,
 
        dev_dbg(npct->dev, "enable group %s, %u pins\n", g->name, g->npins);
 
-       /* Handle this special glitch on altfunction C */
+       /*
+        * If we're setting altfunc C by setting both AFSLA and AFSLB to 1,
+        * we may pass through an undesired state. In this case we take
+        * some extra care.
+        *
+        * Safe sequence used to switch IOs between GPIO and Alternate-C mode:
+        *  - Save SLPM registers (since we have a shadow register in the
+        *    nmk_chip we're using that as backup)
+        *  - Set SLPM=0 for the IOs you want to switch and others to 1
+        *  - Configure the GPIO registers for the IOs that are being switched
+        *  - Set IOFORCE=1
+        *  - Modify the AFLSA/B registers for the IOs that are being switched
+        *  - Set IOFORCE=0
+        *  - Restore SLPM registers
+        *  - Any spurious wake up event during switch sequence to be ignored
+        *    and cleared
+        *
+        * We REALLY need to save ALL slpm registers, because the external
+        * IOFORCE will switch *all* ports to their sleepmode setting to as
+        * to avoid glitches. (Not just one port!)
+        */
        glitch = (g->altsetting == NMK_GPIO_ALT_C);
 
        if (glitch) {