| Message ID | 1303423815-22786-1-git-send-email-riyer@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Apr 21, 2011 at 03:10:15PM -0700, riyer@nvidia.com wrote: > From: Rakesh Iyer <riyer@nvidia.com> > > Add ghost key filtering support for the Nvidia Tegra matrix keyboard. > > Signed-off-by: Rakesh Iyer <riyer@nvidia.com> > --- > v2: Incorporated Henrik Rydberg's suggestions. > v1: Do not report keypresses when matrix keyboard encounters key ghosting. > > arch/arm/mach-tegra/include/mach/kbc.h | 1 + > drivers/input/keyboard/tegra-kbc.c | 36 ++++++++++++++++++++++++++++++++ > 2 files changed, 37 insertions(+), 0 deletions(-) > > diff --git a/arch/arm/mach-tegra/include/mach/kbc.h b/arch/arm/mach-tegra/include/mach/kbc.h > index 04c7798..bd99744 100644 > --- a/arch/arm/mach-tegra/include/mach/kbc.h > +++ b/arch/arm/mach-tegra/include/mach/kbc.h > @@ -58,5 +58,6 @@ struct tegra_kbc_platform_data { > > bool wakeup; > bool use_fn_map; > + bool use_ghost_filter; > }; > #endif > diff --git a/drivers/input/keyboard/tegra-kbc.c b/drivers/input/keyboard/tegra-kbc.c > index 99ce903..56f6668 100644 > --- a/drivers/input/keyboard/tegra-kbc.c > +++ b/drivers/input/keyboard/tegra-kbc.c > @@ -72,6 +72,7 @@ struct tegra_kbc { > unsigned int repoll_dly; > unsigned long cp_dly_jiffies; > bool use_fn_map; > + bool use_ghost_filter; > const struct tegra_kbc_platform_data *pdata; > unsigned short keycode[KBC_MAX_KEY * 2]; > unsigned short current_keys[KBC_MAX_KPENT]; > @@ -260,6 +261,8 @@ static void tegra_kbc_report_keys(struct tegra_kbc *kbc) > unsigned int num_down = 0; > unsigned long flags; > bool fn_keypress = false; > + bool key_in_same_row = false; > + bool key_in_same_col = false; > > spin_lock_irqsave(&kbc->lock, flags); > for (i = 0; i < KBC_MAX_KPENT; i++) { > @@ -285,6 +288,34 @@ static void tegra_kbc_report_keys(struct tegra_kbc *kbc) > } > > /* > + * Matrix keyboard designs are prone to keyboard ghosting. > + * Ghosting occurs if there are 3 keys such that - > + * any 2 of the 3 keys share a row, and any 2 of them share a column. > + * If so ignore the keypresses for this iteration. > + */ > + if ((kbc->use_ghost_filter) && (num_down >= 3)) { > + for (i = 0; i < num_down; i++) { > + unsigned int j; > + u8 curr_col = scancodes[i] & 0x07; > + u8 curr_row = scancodes[i] >> KBC_ROW_SHIFT; > + > + /* > + * Find 2 keys such that one key is in the same row > + * and the other is in the same column as the i-th key. > + */ > + for (j = i + 1; j < num_down; j++) { > + u8 col = scancodes[j] & 0x07; > + u8 row = scancodes[j] >> KBC_ROW_SHIFT; > + > + if (col == curr_col) > + key_in_same_col = true; > + if (row == curr_row) > + key_in_same_row = true; > + } > + } > + } > + > + /* > * If the platform uses Fn keymaps, translate keys on a Fn keypress. > * Function keycodes are KBC_MAX_KEY apart from the plain keycodes. > */ > @@ -297,6 +328,10 @@ static void tegra_kbc_report_keys(struct tegra_kbc *kbc) > > spin_unlock_irqrestore(&kbc->lock, flags); > > + /* Ignore the keypresses for this iteration? */ > + if (key_in_same_col && key_in_same_row) > + return; > + > tegra_kbc_report_released_keys(kbc->idev, > kbc->current_keys, kbc->num_pressed_keys, > keycodes, num_down); > @@ -652,6 +687,7 @@ static int __devinit tegra_kbc_probe(struct platform_device *pdev) > input_dev->keycodemax *= 2; > > kbc->use_fn_map = pdata->use_fn_map; > + kbc->use_ghost_filter = pdata->use_ghost_filter; > keymap_data = pdata->keymap_data ?: &tegra_kbc_default_keymap_data; > matrix_keypad_build_keymap(keymap_data, KBC_ROW_SHIFT, > input_dev->keycode, input_dev->keybit); > -- > 1.7.1 > Reviewed-by: Henrik Rydberg <rydberg@euromail.se> Thanks, Henrik -- 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 Thu, Apr 21, 2011 at 03:10:15PM -0700, riyer@nvidia.com wrote: > From: Rakesh Iyer <riyer@nvidia.com> > > Add ghost key filtering support for the Nvidia Tegra matrix keyboard. > Queued for 2.6.40, thanks Rakesh.
diff --git a/arch/arm/mach-tegra/include/mach/kbc.h b/arch/arm/mach-tegra/include/mach/kbc.h index 04c7798..bd99744 100644 --- a/arch/arm/mach-tegra/include/mach/kbc.h +++ b/arch/arm/mach-tegra/include/mach/kbc.h @@ -58,5 +58,6 @@ struct tegra_kbc_platform_data { bool wakeup; bool use_fn_map; + bool use_ghost_filter; }; #endif diff --git a/drivers/input/keyboard/tegra-kbc.c b/drivers/input/keyboard/tegra-kbc.c index 99ce903..56f6668 100644 --- a/drivers/input/keyboard/tegra-kbc.c +++ b/drivers/input/keyboard/tegra-kbc.c @@ -72,6 +72,7 @@ struct tegra_kbc { unsigned int repoll_dly; unsigned long cp_dly_jiffies; bool use_fn_map; + bool use_ghost_filter; const struct tegra_kbc_platform_data *pdata; unsigned short keycode[KBC_MAX_KEY * 2]; unsigned short current_keys[KBC_MAX_KPENT]; @@ -260,6 +261,8 @@ static void tegra_kbc_report_keys(struct tegra_kbc *kbc) unsigned int num_down = 0; unsigned long flags; bool fn_keypress = false; + bool key_in_same_row = false; + bool key_in_same_col = false; spin_lock_irqsave(&kbc->lock, flags); for (i = 0; i < KBC_MAX_KPENT; i++) { @@ -285,6 +288,34 @@ static void tegra_kbc_report_keys(struct tegra_kbc *kbc) } /* + * Matrix keyboard designs are prone to keyboard ghosting. + * Ghosting occurs if there are 3 keys such that - + * any 2 of the 3 keys share a row, and any 2 of them share a column. + * If so ignore the keypresses for this iteration. + */ + if ((kbc->use_ghost_filter) && (num_down >= 3)) { + for (i = 0; i < num_down; i++) { + unsigned int j; + u8 curr_col = scancodes[i] & 0x07; + u8 curr_row = scancodes[i] >> KBC_ROW_SHIFT; + + /* + * Find 2 keys such that one key is in the same row + * and the other is in the same column as the i-th key. + */ + for (j = i + 1; j < num_down; j++) { + u8 col = scancodes[j] & 0x07; + u8 row = scancodes[j] >> KBC_ROW_SHIFT; + + if (col == curr_col) + key_in_same_col = true; + if (row == curr_row) + key_in_same_row = true; + } + } + } + + /* * If the platform uses Fn keymaps, translate keys on a Fn keypress. * Function keycodes are KBC_MAX_KEY apart from the plain keycodes. */ @@ -297,6 +328,10 @@ static void tegra_kbc_report_keys(struct tegra_kbc *kbc) spin_unlock_irqrestore(&kbc->lock, flags); + /* Ignore the keypresses for this iteration? */ + if (key_in_same_col && key_in_same_row) + return; + tegra_kbc_report_released_keys(kbc->idev, kbc->current_keys, kbc->num_pressed_keys, keycodes, num_down); @@ -652,6 +687,7 @@ static int __devinit tegra_kbc_probe(struct platform_device *pdev) input_dev->keycodemax *= 2; kbc->use_fn_map = pdata->use_fn_map; + kbc->use_ghost_filter = pdata->use_ghost_filter; keymap_data = pdata->keymap_data ?: &tegra_kbc_default_keymap_data; matrix_keypad_build_keymap(keymap_data, KBC_ROW_SHIFT, input_dev->keycode, input_dev->keybit);