[PATCH] chardev: GPIO for SCx200 & PC-8736x: display pin values in/out in gpio_dump

Add current pin settings to gpio_dump() output.  This adds the last 'word' to
the syslog lines, which displays the input and output values that the pin is
set to.

  pc8736x_gpio.0: io00: 0x0044 TS OD PUE  EDGE LO DEBOUNCE        io:1/1

The 2 values may differ for a number of reasons:
1- the pin output circuitry is diaabled, (as the above 'TS' indicates)
2- it needs a pullup resistor to drive the attached circuit,
3- the external circuit needs a pullup so the open-drain has something
   to pull-down
4- the pin is wired to Vcc or Ground

It might be appropriate to add a WARN for 2,3,4, since they could
damage the chip and/or circuit, esp if misconfig goes unnoticed.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/char/nsc_gpio.c b/drivers/char/nsc_gpio.c
index d0b5d65..5b91e4e 100644 (file)
--- a/drivers/char/nsc_gpio.c
+++ b/drivers/char/nsc_gpio.c
@@ -26,7 +26,7 @@ void nsc_gpio_dump(struct nsc_gpio_ops *amp, unsigned index)
        u32 config = amp->gpio_config(index, ~0, 0);
 
        /* user requested via 'v' command, so its INFO */
-       dev_info(amp->dev, "io%02u: 0x%04x %s %s %s %s %s %s %s\n",
+       dev_info(amp->dev, "io%02u: 0x%04x %s %s %s %s %s %s %s\tio:%d/%d\n",
                 index, config,
                 (config & 1) ? "OE" : "TS",      /* output-enabled/tristate */
                 (config & 2) ? "PP" : "OD",      /* push pull / open drain */
@@ -34,7 +34,9 @@ void nsc_gpio_dump(struct nsc_gpio_ops *amp, unsigned index)
                 (config & 8) ? "LOCKED" : "",    /* locked / unlocked */
                 (config & 16) ? "LEVEL" : "EDGE",/* level/edge input */
                 (config & 32) ? "HI" : "LO",     /* trigger on rise/fall edge */
-                (config & 64) ? "DEBOUNCE" : "");        /* debounce */
+                (config & 64) ? "DEBOUNCE" : "", /* debounce */
+
+                amp->gpio_get(index), amp->gpio_current(index));
 }
 
 ssize_t nsc_gpio_write(struct file *file, const char __user *data,