This is a note to let you know that I've just added the patch titled Input: tca8418_keypad - hide gcc-4.9 -Wmaybe-uninitialized warning to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: input-tca8418_keypad-hide-gcc-4.9-wmaybe-uninitialized-warning.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From ea4348c8462a20e8b1b6455a7145d2b86f8a49b6 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann <arnd@xxxxxxxx> Date: Wed, 26 Oct 2016 15:55:02 -0700 Subject: Input: tca8418_keypad - hide gcc-4.9 -Wmaybe-uninitialized warning MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Arnd Bergmann <arnd@xxxxxxxx> commit ea4348c8462a20e8b1b6455a7145d2b86f8a49b6 upstream. Older versions of gcc warn about the tca8418_irq_handler function as they can't keep track of the variable assignment inside of the loop when using the -Wmaybe-unintialized flag: drivers/input/keyboard/tca8418_keypad.c: In function ‘tca8418_irq_handler’: drivers/input/keyboard/tca8418_keypad.c:172:9: error: ‘reg’ may be used uninitialized in this function [-Werror=maybe-uninitialized] drivers/input/keyboard/tca8418_keypad.c:165:5: note: ‘reg’ was declared here This is fixed in gcc-6, but it's possible to rearrange the code in a way that avoids the warning on older compilers as well. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/input/keyboard/tca8418_keypad.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) --- a/drivers/input/keyboard/tca8418_keypad.c +++ b/drivers/input/keyboard/tca8418_keypad.c @@ -164,11 +164,18 @@ static void tca8418_read_keypad(struct t int error, col, row; u8 reg, state, code; - /* Initial read of the key event FIFO */ - error = tca8418_read_byte(keypad_data, REG_KEY_EVENT_A, ®); + do { + error = tca8418_read_byte(keypad_data, REG_KEY_EVENT_A, ®); + if (error < 0) { + dev_err(&keypad_data->client->dev, + "unable to read REG_KEY_EVENT_A\n"); + break; + } + + /* Assume that key code 0 signifies empty FIFO */ + if (reg <= 0) + break; - /* Assume that key code 0 signifies empty FIFO */ - while (error >= 0 && reg > 0) { state = reg & KEY_EVENT_VALUE; code = reg & KEY_EVENT_CODE; @@ -184,11 +191,7 @@ static void tca8418_read_keypad(struct t /* Read for next loop */ error = tca8418_read_byte(keypad_data, REG_KEY_EVENT_A, ®); - } - - if (error < 0) - dev_err(&keypad_data->client->dev, - "unable to read REG_KEY_EVENT_A\n"); + } while (1); input_sync(input); } Patches currently in stable-queue which might be from arnd@xxxxxxxx are queue-4.9/kasan-rework-kconfig-settings.patch queue-4.9/tw5864-use-dev_warn-instead-of-warn-to-shut-up-warning.patch queue-4.9/perf-x86-shut-up-false-positive-wmaybe-uninitialized-warning.patch queue-4.9/go7007-add-media_camera_support-dependency.patch queue-4.9/scsi-advansys-fix-build-warning-for-pci-n.patch queue-4.9/video-fbdev-via-remove-possibly-unused-variables.patch queue-4.9/drm-exynos-mark-pm-functions-as-__maybe_unused.patch queue-4.9/binfmt_elf-compat-avoid-unused-function-warning.patch queue-4.9/idle-i7300-add-pci-dependency.patch queue-4.9/cw1200-fix-bogus-maybe-uninitialized-warning.patch queue-4.9/x86-build-silence-the-build-with-make-s.patch queue-4.9/gpio-xgene-mark-pm-functions-as-__maybe_unused.patch queue-4.9/kvm-add-x86_local_apic-dependency.patch queue-4.9/reiserfs-avoid-a-wmaybe-uninitialized-warning.patch queue-4.9/scsi-advansys-fix-uninitialized-data-access.patch queue-4.9/drm-i915-fix-intel_backlight_device_register-declaration.patch queue-4.9/spi-bcm-qspi-shut-up-warning-about-cfi-header-inclusion.patch queue-4.9/asoc-ux500-add-module_license-tag.patch queue-4.9/x86-microcode-amd-change-load_microcode_amd-s-param-to-bool-to-fix-preemptibility-bug.patch queue-4.9/video-fbdev-mmp-add-module_license.patch queue-4.9/usb-phy-msm-add-regulator-dependency.patch queue-4.9/arm64-dts-add-cooling-cells-to-cpu-nodes.patch queue-4.9/vmxnet3-prevent-building-with-64k-pages.patch queue-4.9/x86-platform-add-pci-dependency-for-punit_atom_debug.patch queue-4.9/alsa-hda-ca0132-fix-possible-null-pointer-use.patch queue-4.9/thermal-fix-intel_soc_dts_iosf_core-dependencies.patch queue-4.9/arm64-define-bug-instruction-without-config_bug.patch queue-4.9/arm64-sunxi-always-enable-reset-controller.patch queue-4.9/tc358743-fix-register-i2c_rd-wr-functions.patch queue-4.9/security-keys-big_key-requires-config_crypto.patch queue-4.9/drm-i915-hide-unused-intel_panel_set_backlight-function.patch queue-4.9/x86-fpu-math-emu-fix-possible-uninitialized-variable-use.patch queue-4.9/arm-8743-1-bl_switcher-add-module_license-tag.patch queue-4.9/em28xx-only-use-mt9v011-if-camera-support-is-enabled.patch queue-4.9/arm64-fix-warning-about-swapper_pg_dir-overflow.patch queue-4.9/shmem-avoid-maybe-uninitialized-warning.patch queue-4.9/input-tca8418_keypad-hide-gcc-4.9-wmaybe-uninitialized-warning.patch queue-4.9/drm-nouveau-hide-gcc-4.9-wmaybe-uninitialized.patch queue-4.9/x86-add-multiuser-dependency-for-kvm.patch queue-4.9/isdn-eicon-reduce-stack-size-of-sig_ind-function.patch