| Message ID | 20170322201650.9072-1-drivshin@awxrd.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, Mar 22, 2017 at 04:16:50PM -0400, David Rivshin wrote: > From: David Rivshin <DRivshin@allworx.com> > > The gpio-matrix-keypad driver normally sets inactive columns as inputs > while scanning. This does not work for all hardware, which may require > the inactive columns to be actively driven in order to overcome any > pull-ups/downs on the columns. > > Signed-off-by: David Rivshin <drivshin@allworx.com> > --- > .../devicetree/bindings/input/gpio-matrix-keypad.txt | 2 ++ > drivers/input/keyboard/matrix_keypad.c | 13 +++++++++---- > include/linux/input/matrix_keypad.h | 3 +++ > 3 files changed, 14 insertions(+), 4 deletions(-) Acked-by: Rob Herring <robh@kernel.org> -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Mar 28, 2017 at 09:02:29PM -0500, Rob Herring wrote: > On Wed, Mar 22, 2017 at 04:16:50PM -0400, David Rivshin wrote: > > From: David Rivshin <DRivshin@allworx.com> > > > > The gpio-matrix-keypad driver normally sets inactive columns as inputs > > while scanning. This does not work for all hardware, which may require > > the inactive columns to be actively driven in order to overcome any > > pull-ups/downs on the columns. > > > > Signed-off-by: David Rivshin <drivshin@allworx.com> > > --- > > .../devicetree/bindings/input/gpio-matrix-keypad.txt | 2 ++ > > drivers/input/keyboard/matrix_keypad.c | 13 +++++++++---- > > include/linux/input/matrix_keypad.h | 3 +++ > > 3 files changed, 14 insertions(+), 4 deletions(-) > > Acked-by: Rob Herring <robh@kernel.org> Applied, thank you.
diff --git a/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt b/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt index d0ea09b..570dc10 100644 --- a/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt +++ b/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt @@ -24,6 +24,8 @@ Optional Properties: - debounce-delay-ms: debounce interval in milliseconds - col-scan-delay-us: delay, measured in microseconds, that is needed before we can scan keypad after activating column gpio +- drive-inactive-cols: drive inactive columns during scan, + default is to turn inactive columns into inputs. Example: matrix-keypad { diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c index 18839cd..1f316d6 100644 --- a/drivers/input/keyboard/matrix_keypad.c +++ b/drivers/input/keyboard/matrix_keypad.c @@ -42,9 +42,10 @@ struct matrix_keypad { }; /* - * NOTE: normally the GPIO has to be put into HiZ when de-activated to cause - * minmal side effect when scanning other columns, here it is configured to - * be input, and it should work on most platforms. + * NOTE: If drive_inactive_cols is false, then the GPIO has to be put into + * HiZ when de-activated to cause minmal side effect when scanning other + * columns. In that case it is configured here to be input, otherwise it is + * driven with the inactive value. */ static void __activate_col(const struct matrix_keypad_platform_data *pdata, int col, bool on) @@ -55,7 +56,8 @@ static void __activate_col(const struct matrix_keypad_platform_data *pdata, gpio_direction_output(pdata->col_gpios[col], level_on); } else { gpio_set_value_cansleep(pdata->col_gpios[col], !level_on); - gpio_direction_input(pdata->col_gpios[col]); + if (!pdata->drive_inactive_cols) + gpio_direction_input(pdata->col_gpios[col]); } } @@ -432,6 +434,9 @@ matrix_keypad_parse_dt(struct device *dev) if (of_get_property(np, "gpio-activelow", NULL)) pdata->active_low = true; + pdata->drive_inactive_cols = + of_property_read_bool(np, "drive-inactive-cols"); + of_property_read_u32(np, "debounce-delay-ms", &pdata->debounce_ms); of_property_read_u32(np, "col-scan-delay-us", &pdata->col_scan_delay_us); diff --git a/include/linux/input/matrix_keypad.h b/include/linux/input/matrix_keypad.h index 37b04a0..6174733 100644 --- a/include/linux/input/matrix_keypad.h +++ b/include/linux/input/matrix_keypad.h @@ -49,6 +49,8 @@ struct matrix_keymap_data { * @wakeup: controls whether the device should be set up as wakeup * source * @no_autorepeat: disable key autorepeat + * @drive_inactive_cols: drive inactive columns during scan, rather than + * making them inputs. * * This structure represents platform-specific data that use used by * matrix_keypad driver to perform proper initialization. @@ -73,6 +75,7 @@ struct matrix_keypad_platform_data { bool active_low; bool wakeup; bool no_autorepeat; + bool drive_inactive_cols; }; int matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,